BE1014656A5 - Solar collector for building has window frames with hollow frame members forming ducts for heat exchange fluid - Google Patents

Abstract

The window has hollow metal frame members in which brine circulates as a heat exchange medium to capture solar heat. The heat is stored in an accumulator to be transferred to a heating circuit during the night. The heating circuit uses a heat pump and convection heaters. The conveyor heaters can replace all the walls of the building.

Description

       

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  DESCRIPTION Construction process including a heating system using electric energy for the recovery of renewable energies.



  Introduction
To date, we recover renewable energies, by sensor and heat pump, most often individually without the possibility of storage and therefore these processes are little used.



   In the past, it was well thought out to store solar energy, as shown by a French patent filed in 1977, among other things, but this process, like the others, always requires too much water to store calories.



   It has never been shown that it is possible to completely do without fossil fuels in new homes.



   The main interest of the new process lies in the fact that we no longer use fossil energy, we achieve significant energy savings and a considerably reduced energy cost.



   A storage tank is no longer necessary.



   This process makes it possible to reduce the quantity of C02 normally released with fossil fuels to 1/6. It uses only electrical energy but in a quantity three times less. If in Belgium 50% of the electrical energy would be of atomic origin, we would produce six times less C02.



   Among the renewable energies, which it is necessary to store, we have solar energy, that of air and wind energy, because they appear by more or less long periods and variable durations of several days consecutive.



   The other energies: that of the ground (surface geothermal or deep geothermal), that withdrawn from the water (lake, pond, river) do not need to be stored. They can be used directly without going through our process.



  However, they will be advantageously used sometimes and in addition to our process, if they are available.



   After having graphed, day after day, during the last 15 years the outside temperatures (Fig. 1 to 4), the coldest in the morning and the warmest in the afternoon, as well as the days with more than 70 / % of sun, (Fig. 5) we note the interesting alternation mainly in winter: either that the sun is present and the air temperature low for example in frost, or that the sun is absent and the temperature higher air; hence the interest in removing these two energies which complement each other as a priority.



   We also note that after heating the house during these periods, it is possible to store a large part and that with this stock, we can maintain a comfortable temperature on days, or more often the periods during which these energies are absent. The volume of water required for storage is reduced, but this problem remains.



   With the new process, the volume of water is reduced and a tank becomes useless because here, all the interior walls are replaced by convectors in which we find the necessary volume of water. (Fig. 6)
Prefabricated convectors with standardized dimensions are used (1) (2) (3)
These convectors consist of a tank of parallelepiped shape, most often from 10 to 20 cm thick enclosed between two insulating partitions, spaced a few cm apart. (50) for air circulation with openings at the bottom and the top to ensure convection. Adjustable shutters in the upper openings will measure the amount of heat to bring to maintain the comfort temperature.



   All of these convectors constitute the heating circuit.



   Following the previous observation, solar heat and air heat are recovered as a priority. We do not take into account wind energy, which is very interesting in winter because of the price (In 1980 a domestic wind turbine returned to 7,500 e), the noise and the breakage of the blades which forced its installation too far from the houses. .



   As the price per kWh varies greatly between day and night, for reasons of economy, the sequence is as follows:
Extraction of solar heat
Currently it is most often captured by solar panels, but here in the process, we prefer to collect it inside the house.



   In the room receiving the sun, the heat is captured at the level of the ceiling by exchangers. As an exchanger, we preferably use joists and slabs which serve as load-bearing elements but in a tubular steel form, in which a cold brine circulates. This provides the frigories necessary to maintain the comfort temperature. We will therefore try to install a maximum of glazing on the south side of the house and no longer worry about overheating. This is very possible today with multi-glazing with low emissivity. Due to the difference in price per kWh, the heat is stored in an accumulator at a temperature close to 25 and at night this heat is transferred by a heat pump at a temperature of up to 50.



   The joists and the slabs are tubes of several m. in length, for example of rectangular section 20 * 5 cm. and in 1.5 mm sheet. thick. When this tube is placed vertically, it is considered as a joist (4) and placed flat as a slab (5). (Fig. 7)
The accumulator has enough volume to capture the excess heat from a day of sunshine.



   To the heat captured preferably by the windows, one can add that coming from solar panels most often in addition to the glazed surface. This heat is also stored in the accumulator, or transmitted directly into the heating circuit by concentrated solar panels. At the moment the price of these solar panels especially in concentration is too high.



   Extraction of heat from the air
It is extracted by a heat exchanger, the liquid circuit of which is used as an evaporator for the heat pump. The outside air temperature must be above 5. The heat transferred by the heat pump can reach 50 if necessary. For reasons of economy, heat is extracted from the air at night.

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   Capturing energy from the ground
When you can no longer remove enough heat from the sun and the air and the reserve in the heating circuit is exhausted, this energy is removed from the ground at night.



   It is obtained by sensors buried about 1 m in the ground according to methods known in this field.



  The disadvantage is that they require a collection area more often than three times that of the heated part of the house.
With the equipment used in our process, it is possible to re-inflate the soil in calories when the air temperature is higher than the temperature at the level of the sensors
The collection area can be considerably reduced.



   Air energy capture during the day.



   When the three previous sources are exhausted, it is possible to capture the air during the day according to the principle used at night, but at a price three times higher
Electric power at night
It is the last source to use when all the previous ones are absent because it is the most expensive energy.



    @) Construction process including a fully electric heating system capable of recovering free energy (sun and outside calories)
Unlike conventional central heating, here there is no bulky radiator or exposed pipe in the home.



   Let us say immediately, that by this process, the cost of the electrical energy required calculated compared to fuel oil allows a saving of approximately 620 0 (25,000Fb) per year in the type of "pilot" dwelling which will be studied.



   We no longer use fossil fuels and thus save the equivalent of 2,500 liters of fuel per year that would have been necessary to produce the same amount of heat.



   Currently, the different heating modes used in homes are in order:
1 - mainly central heating, fireplaces, inserts, etc., using fossil fuels: fuel, gas, coal, etc.



   2 - less frequent electric heating: accumulators and convectors.



   3 - shyly the energies: solar, air, water and geothermal.



   Given the increasing prices of fossil fuels, but especially the C02 released, there is great interest in reversing the previous order by first using solar energy and then the energy contained in air, water, soil and supplement with the energy supplied by electrical resistors, if necessary.



   After having recorded in graphs during the last 15 years, day after day, the atmospheric conditions: minimum temperature in the morning, maximum temperature in the afternoon and on days with more than 70% of sun, we see that we have two possible sources, which one meets everywhere: solar heat and the heat contained in the air, then a third, quite often available: heat of the ground.



   We will see that it becomes possible to get rid of fossil fuels by using only electricity.



  Sum of sunny periods from early October to late May (Fig. 5)
 EMI2.1
 
 <tb> Periods <SEP> No. <SEP> from <SEP> days <SEP> In <SEP>%
 <Tb>
 <tb> 86/87 <SEP> 75 <SEP> 30 <September>
 <Tb>
 <tb> 87/88 <SEP> 91 <SEP> 37 <September>
 <Tb>
 <tb> 88/89 <SEP> 116 <SEP> 47 <September>
 <Tb>
 <tb> 89/90 <SEP> 119 <SEP> 49 <September>
 <Tb>
 <tb> 90/91 <SEP> 117 <SEP> 48 <September>
 <Tb>
 <tb> 91/92 <SEP> 107 <SEP> 44 <September>
 <Tb>
 <tb> 92/93 <SEP> 96 <SEP> 39
 <Tb>
 <tb> 93/94 <SEP> 67 <SEP> 27
 <Tb>
 <tb> 94/95 <SEP> 87 <SEP> 36 <September>
 <Tb>
 <tb> 95/96 <SEP> 81 <SEP> 33 <September>
 <Tb>
 <tb> 96/97 <SEP> 84 <SEP> 34 <September>
 <Tb>
 <tb> 97/98 <SEP> 85 <SEP> 35 <September>
 <Tb>
 <tb> 98/99 <SEP> 61 <SEP> 25 <September>
 <tb> 99/00 <SEP> 54 <SEP> 22 <September>
 <Tb>
 <Tb>
 <tb> 00/01 <SEP> 64 <SEP> 26 <September>
 <Tb>
 

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 Comparison of fuel and electricity energies
In 1992, According to the BBRI,

   for heating, 840 liters of fuel equivalent to 5,370 kWh of electricity, as these 5,370 kWh correspond to 5,370 * 860 = 4,618,200 k Calories, 1 liter of fuel produced: 4,618,200 840 5,498 k Calories. The higher calorific value of the fuel being 10,000 kCal, the yield was 55%.



   Improvements have been made since 1992 and it appears that the average current yield is 70%.



  In all the calculations that follow we therefore assume that 1 liter of fuel supplies by burning 7,000 kCal.



  A - Solar energy.



   In new homes, where possible, for the purpose of comfort and solar energy recovery, the living room is spacious, facing south and has large picture windows.



   Unfortunately, the solar heat is badly used, the room temperature quickly becomes unbearable, the calories are concentrated under the ceiling raising the temperature until reaching a temperature in equilibrium with the coefficient of loss of this ceiling. This heat is lost; this fact, we limit the dimensions of these bay windows and do not take full advantage of this energy.



   The new low-emissivity glazing makes it possible, thanks to their low transfer coefficient (1.12 kCal / m2 hour / C), to transform the rooms receiving the sun into real sensors.



   In the process envisaged, the heat is captured, removed and stored, so that the comfort temperature is not exceeded.



   A few years ago, it was difficult to envisage recovering solar heat through the windows because the heat loss through them was too high.



   For single glazing, the transfer coefficient is 5.8 W / m2k and double glazing: 2.9 W / m2k; the recovered heat was lost through the windows. With the progress made, we have reached 1.3 W / mk.



   Hopefully, new discoveries will further improve this coefficient to reach a value close to the insulation we reach for walls, floors and ceilings and which oscillates between 0.3 and 0.4 W / mk.



  Energy supplied by the sun
It varies with the seasons. According to the documentation, the maximum reached during strong sunshine is 900 kcal / m 2 / h and falls to 175 kCal under the clouds. In winter, in good weather, around 450 kCal.



   These values are obtained for rays falling perpendicularly on the measurement surface in our region. They are distributed, according to the month and according to the position of the sun during the heating period:
October 650 kcal / m 2 / hour February 500
November 500 March 600
December 400 April 690
January 430 May 750
The sun moves horizontally from East to West.



  At the winter solstice the duration of sunshine is 7 h 30, and that of summer is 16 h
On a glass surface exposed to the South, at 6 a.m. the rays fall tangentially and it is practically from 6.30 a.m. that the rays penetrate until 5.30 p.m. It will be useless to take into account the presence of the sun before 6:30 a.m. and after 5:30 p.m.
For a window of width "1", the real value of sunshine is therefore r (17) = 1 (19) * sin (18) (Fig. 8) Variations of "r" according to the hour.



  At 6.30 a.m. and 5.30 p.m. ce = 7.5 sin oc = 0.13
7:30 a.m. and 4:30 p.m. = 22.5 sin = 0.38 8:30 a.m. and 3:30 p.m. 0 ce = 3 7.5 sin oc = 0.61
9:30 a.m. and 2:30 p.m. ce = 52.5 sin oc = 0.79
10:30 a.m. and 1:30 p.m. oc = 67.5 sin oc = 0.92 11:30 a.m. and 12:30 p.m. ce = 82.5 sin oc = 0.99 Duration of illumination, depending on the month and sum of the illuminations collected on throughout the day. duration of sun sum of sin.



   October 7:30 a.m. to 5:30 p.m. 0.38 to 0.13 = 7.5
November 7:30 a.m. to 4:30 p.m. 0.38 to 0.38 = 7.4
December 8:30 a.m. to 4:30 p.m. 0.61 to 0.38 = 7
January 8:30 a.m. to 5:30 p.m. 0.61 to 0.13 = 7.1
February 7:30 a.m. to 5:30 p.m. 0.38 to 0.13 = 7.5
March 6:30 a.m. to 5:30 p.m. 0.13 to 0.13 = 7.6
April "
May "" Actual heat captured per day of full sun
October 650 * 7.5 = 4.875 kCal / m2 / day.



   November 500 * 7.4 = 3.700 "
December 400 * 7 = 2.800 "
January 430 * 7.1 = 3.053 "
February 500 * 7.5 = 3. 750 "
Mars 600 * 7.6 = 4.560 "
April 690 * 7.6 = 5.244 "
May 750 * 7.6 = 5.700 "

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 Record of sunshine and outside temperatures.



   As already explained, we have noted daily since 1986 the days with more than 70% of sun: - temperatures in the morning.



   - the temperatures in the afternoon, in order to know the calories supplied by the sun, the calories lost by the dwelling and from there, the recoverable calories.



  Below, among these graphs, those noted for the years, on which the following calculations will relate: - October 1991 to May 92: which is an average year from the point of view of temperatures. (Fig. 3 & 4) - October 1990 to May 91: a very cold year with significant frost from December to February (until -13) (Fig. 1 & 2) - We do not take into account the years before October 90 for calculations, because at that time we only recorded the temperature in the morning.



   By counting 70% of sun, the calories supplied per m2 and per day are reduced again:
October 4,875 * 0.7 = 3,412 kCal / m2 / day.



   November 3. 700 2. 590 "
December 2.800 1. 960 "
January 3.053 2.137 "
February 3. 750 2. 625 "
March 4.560 3. 192 "
April 5. 244 3. 670 "
May 5. 700 3. 990 "
In these calculations, we do not take into account the heat supplied on less sunny or overcast days, which the process uses, difficult to quantify, but nevertheless non-negligible.



  Heat recovered in a home.



   It is therefore advisable to build with a maximum of glazing and no longer worry about overheating; which will be possible by removing the calories by a heat pump, to replace them by frigories, balancing the temperature, these calories captured will be stored.



   For a house with no floor, the large windows will be located on the south side; for a house with floors, the glazing will be installed both at the bottom and at the top, everything will depend on the neighborhood.



   Other possibilities can be used to increase the glazed area, for example by combining the front bay windows and overhead windows on the facade and on the roof, projecting windows, etc. On the roof, on the exterior walls, solar panels can contribute considerably to the contribution provided by windows, especially in the city (shaded areas).



   To simplify the following calculations, we have imagined a very simple "pilot home" (Fig. 9 & 10): floor space of 24 m by 10 m - without floor.



   - an attic whose roof is not insulated and where the temperature is the same as outside.



   - walls made of aerated concrete blocks.



   - a well insulated ceiling.



   - the longest facade (24 m) (20) faces south, and has a maximum of glazing to avoid the costs generated by solar panels.



  The glazed surface facing south is 32.5 m2. The amount of calories captured will be: in October 3,412 * 32.5 = 110,890 kCal per day of sunshine
November 2.590 * 32.5 = 84. 175 "
December 1.960 * 32.5 = 63.700 "
January 2.137 * 32.5 = 69. 452 "
February 2.625 * 32.5 = 85.312 "
March 3.192 * 32.5 = 103.740 "
April 3.670 * 32.5 = 119.275 "
May 3.990 * 32.5 = 129. 675 "
For the calculations below, we only consider the solar heat entering through the bay windows, knowing that these latter values can be increased by combining glazing and solar panels; that the process of capturing solar energy by bay windows is a low temperature capture perfectly compatible with flat solar collectors much less expensive than concentrated collectors.



  Sunshine periods.



   The graph (Fig. 5) taken from daily graphs since 1986 gives for each heating period from October to the end of May the sum of sunny periods whose average over the 15 years is 35% (almost 1 day out of 3)
Unfortunately the sun does not shine regularly 1 day on 3 but for more or less long periods and the excess heat must be stored.



   We know the quantity of heat supplied by the sun, calculate the quantity of heat lost by the dwelling; it is this difference that should be stored for days without sun.



  Heat lost by housing
This heat is lost through exterior walls, glazing, doors and windows, the ceiling, the floor, the renewal of air.

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   Calculations.



  - Walls in aerated concrete 30 cm thick covered with plaster
The manufacturer gives in this case an average coefficient:
K = 0.43 W / m2 k, i.e. 0.43 * 0.86 = 0.37 kCal / m2 / h C.



   Glazing The new low emissivity glazing
K = 1.3 W / m2 k, i.e. 1.3 * 0.86 = 1.12 kCal / m2 / h / C.



  - Insulated ceiling (floor + polystyrene + floor) placed on the joists. (Fig. 11) wooden floor 2 cm thick (24) K = 3 polystyrene 4 cm (25) K = 2.5 wooden floor 2 cm (24) K = 3
Thermal resistance: 0.1 + 0.66 + 0.25 + 1.6 + 0.25 + 0.66 + 0.1 = 3.62 K = 1 / 3.62 = 0.27 kCal - Soil:

   On ground leveled with sand, covered with a polyethylene film, a 4 cm layer of polystyrene, a 15 cm reinforced concrete slab, and a 10 cm screed concrete-air interface K = 10 R th = 0.1 10 cm screed K = 70/10 R th = 0.14 concrete-reinforced concrete interface K = 4 R th = 0.25 15 cm reinforced concrete K = 80/15 R th = 0 , 18 interface K = 4 R th = 0.25 polystyrene K = 3.5 / 4 R th = 1.14
Thermal resistance = 2.06 hence K = 0.48 Taking into account in the calculations of the outside temperature, we most often take 1/3 i.e. 0.48 / 3 = 0.16
2 cm thick wooden garage door (23) air interface K = 10 Rth = 0.1 wood K = 3.2 / 2 R th = 0.62 air interface K = 10 R th = 0.1
Total R th = 0.82 and K = 1 / 0.82 = 1.21 - Air renewal: the loss is estimated at 0.06 times the volume in kCal per hour.

   (whole volume of the dwelling renewed once every 5 hours) K = V / 5 * 1.2 * 0.24 = 0.06 V kCal / h / C Transfer and heating circuit
On sunny days, a significant amount of heat penetrates through the glazing, but at the same time a fraction is lost in these same rooms outside and it is the surplus of calories which will be captured, stored at a much higher temperature and at the same time replaced by an equivalent amount of frigories so that the temperature remains constant.



   The heat is captured by an exchanger located on the ceiling and connected to the evaporator of the heat pump. When the temperature in the vicinity of the exchanger reaches 25, the heat pump will operate as well as the circulation pump delivering water to the exchanger at low temperature.



   This is problematic because the heat pump operates during the day when the price of electrical energy is highest.



   The day from 7 a.m. to 10 p.m. the kW costs 0.155 # (6.28 Fb).



   At night from 10 p.m. to 7 a.m. 0.069 # (2.80 Fb). bi-hourly. and 0.056 # (2.28 Fb). in exclusive night.



    We will therefore use a heat accumulator: tank containing a sufficient volume of water to capture calories on sunny days and pump them out at night by the heat pump into the heating circuit (at the exclusive night tariff).



    We arrive at the following principle diagram: transfer circuit (35) and a heating circuit (36) connected by the heat pump (30): (Fig. 12) - E exchanger located on the ceiling. (26) - Ac heat accumulator. (27) - PC1 circulation pump of the transfer circuit. (28) - th a contact thermometer located on the ceiling. (29) - Heat pump heat pump. (30) - Ev evaporator of the heat pump.

   (31) - Co-condenser of the heat pump. (32) - PC2 evaporator circulation pump. (33) - PC3 heating circuit circulation pump. (34) The transfer circuit contains brine, which must be capable of not freezing for a temperature of -10 and anti-rust.

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  Solar heat balance.



  - At night, the heat pump extracts heat from Ac and sends it into the heating circuit.



  - In the morning, the brine contained in Ac can reach a temperature close to -3 and when tha indicates 25,
PCI works and injects brine into E.



  - In the evening AC has absorbed the calories found in the top of the tank at a temperature close to 25.



   Under these conditions the heat pump will absorb - 10,000 kCal by consuming 3.2 kWh, and will supply 12,570 kCal for a temperature of the heating circuit varying from 0 to 25 and - 10,000 kCal by consuming 4.15 kWh to supply 13,570 kCal for a temperature variation from 0 to 50.



   For the calculations, an average yield will be taken: - 10,000 kCal at the inlet of the pump consuming 3.85 kW and producing 13,070 kCal (the compression work is found in the form of heat), ie a ratio of heat supplied / heat absorbed = 1 , 3 (see in more detail heat pump).



   For the calculation, it will be necessary to separate the heat losses from the sunny rooms from the others.



   1 - Heat lost by the rooms receiving the sun: 139 kCal
2 - Heat lost by the rest of the house: 103 kCal
The total loss by the building will be 139 + 103 = 242 kCal / h / C or 5.805 kCal / day / C.



  By calling t the duration of sunshine t 1 the outside temperature in the morning t 2 the outside temperature in the afternoon
At the temperature difference between the interior (20) and the exterior
ES solar energy supplied during the day
1.3 the ratio between calories supplied and absorbed
P the total loss of heat by the building pl the loss in sunny rooms during the period of sunshine = 139 * t * A t p2 the rest of the loss = P - pl The solar energy captured in the evening will be ES - pl and that supplied to the heating circuit: 1.3 (ES - pl).



  Note that p2 is equal to: (5805 - 139 * t) ¯ t
This leads to the following tables for the year 91-92 given below as an example. The following monthly tables represent these various values for this year 91-92 1st column: the date 2e 1 l 3e t 2 4th ¯ t 5th S, the sunny days 6th P, the calories lost by the whole building according to the outside temperature 7th pl, the calories lost during the sunshine period 8th p2, the remaining loss on sunny days 9th F, the calories supplied by the heat pump F = 1.3 (ES-pl) 10th at St., ( F - p2): amount of excess heat to be stored in the heating circuit.



  The other columns will be seen later.



   YEAR 1991 - 1992
OCTOBER date t l t 2 t S P pl p2 F at St. Stock Fx Air RAF
450,000 1 10 19 6 * 34,830 8,340 26,490 133,315.106,825 556,825 133,315 - - 2 8 15 9 * 52,245 12,510 39,735 127,894.88,159 644,984 127,894 - - 3 7 18 8 * 46,440 11,120 35,320 127,901. 94,381 739,365 129,701 - - 4 8 19 7 * 40,635 9,730 30,905 131508x 100603 750000 41540 - - 5 9 22 4 23220 "17861 - 6 13 21 3 * 17415 4170 13245 138736x 125491" 13245 - - 7 12 20 4 * 23220 5560 17060 136928x 119269 "17660 - - 8 11 19 5 * 29025 6950 22075 135122x 113047 "22075 - - 9 9 20 5 *" "" "" "" - - 10 10 22 4 * 23220 5560 17660 136929x 119269 "17660 - - 11 13 20 3 * 17415 4170 13245 138736x 125491" 13245 - - 12 12 22 3 * "" "" "" "" - - 13 9 20 6 * 34 830 8340 26490 133315x 106825

  "26490 - - 14 9 22 5 * 29025 6950 22075 135122x 113047" 22075 - - 15 10 24 3 * 17415 4170 13245 138736x 125491 "13245 - -

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 EMI7.1
 16 7 20 7 * 40635 9730 30905 131508x 100603 "30905 - - 17 6 16 9 - 52245 - - - -" - 40188 - 18 5 12 11 - 63855 - - - - "- 49119 - 19 4 14 11 - 63855 - - - - "- 49119 - 20 3 12 13 - 75465 - - - - 724481 - 38420 - 21 1 10 15 - 87 075 - - - - 700 573 - 48 590 - 22 3 10 14 - 81 270 - - - - 718 834 - 76 560 - 23 4 11 13 - 75465 - - - - 750,000 - 82,023 - 24 7 12 9 - 52,245 - - - - "- 40,188 25 9 13 9 * 52,245 12,510 39,735 127,894 x 88,159 39,735 - - 26 8 14 9 *" "" "" "" " - 27 2 15 12 * 69 660 16 680 52 980 -122 473 69 493 52 980 - - 28 8 14 9 - 52 245 - - - - - - 40 188 29 10 15 7 - 40 635 - - - - "- 31 257 - 30 11 12 9 - 52 245 - - - - "- 40188 - 31 7 13 10 - 58 050 - - - -" - 44 654 - 242 1 404 810 776 820 598 355 242 1 404 810 776 820 598 355

  242 * 5805 = 1404810 200 liters of fuel 12.44 E 10.93 E to 0.37 E 74.36 # total sun + air 23.37 E NOVEMBER date tt 2 t SP p p2 F at St. Stock Fx Air RAF 1 8 14 9 52 245 - - - 750 000 - 40 188 - 2 7 12 10 - 58 050 - - - - "- 44 653 - 3 9 10 11 - 63 855 - - - -" - 49 119 - 4 5 8 14 - 81 270 - - - - "- 62,515 - 5 7 10 11 - 63,855 - - - - 706,555 - 15,700 - 6 0 12 14 - 81,270 - - - - 750,000 - 95,934 - 7 6 10 12 - 69,660 - - - -" - 53,584 - 8 10 12 9 * 52245 11259 40986 94791x 53805 40986 - - 9 4 11 13 - 75465 - - - - 704422 - 22990 - 10 0 9 16 - 92880 - - - - 661806 - 38665 - 11 3 6 15 - 87075 - - - - 706941 - 101700 - 12 6 8 13 - 75 465 - - - 719 778 - 67 925 - 13 4 9 14 - 81 270 - - - - 664 319 - 19855 - 14 1 10 15 - 87 075 - - - - 583 561 - 48 590 - 15 3 12 13 * 75 465 16 263 59 202 88286x 29083 612644 88286 - - 16 1 10 15 - 87 075 - - - - 625 100 - 76562 - 17 4 8 14 * 81 270 17514 63756 86659.

   22903 648003 86659 - - 18 6 10 12 - 69 660 - - - - 708 843 - 130 500 - 19 7 10 11 - 63 855 - - - - 750 000 - 80 778 - 20 5 10 13 - 75 465 - - - - 717 500 - 33056 - 21 2 4 17 - 98685 - - - - 618 815 - - - 22 -1 3 18 - 104 490 - - - 514 325 - 23 0 2 19 * 110 295 23 769 86 526 78 528. -7 998 506 327 78 528 - 24 -2 7 18 - 104 490 - - - 401 837 - - 25 0 6 17 - 98 685 - - - - 391 872 - 14 400 - 26 4 7 14 * 81 270 17514 63 756 86 659. 22 903 344 725 86 659 - - 27 0 10 15 - 87 075 - - - - 291 660 - 26 120 28 1 5 17 * 98 685 21 267 77418 81780. 4362 296022 81780 - 29 0 6 17 - "- - - - 197337 - - 30 2 4 17 -" - - - - 98652 - - 2455515 462898 1022828 350 liters fuel 7.41 E 18.69 ive 130.44 E total = 26.10 E

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 EMI8.1
 DECEMBER date t 1 t 2 t S P pl p2 F â St.

   Stock Fx Air RAF 98652 1 0 3 19 - 110 295- - - - 0 - - 11 643 2 1 4 17 - 98 685 - - - - "- - 98 685 3 2 5 16 - 92 880 - - -" - - 92 880 4 3 4 16 * 92880 17792 75083 59680. -15407 59680 - 15407 5 2 6 16 - 92880 - - - - "- - 92880 6 -4 8 14 * 81270 155168 65702 62572. -3130 62572 - 3130 7 -3 6 19 - 110295- - - - "- - 110 295 8 0 2 19 -" - - - - - "Il 9 2 3 19 * 110 295 21 128 89 167 55 344. -33 823 55 344 - 33 823 10 -4 -1 22 * 127 710 24 464 103 246 51 007.-52 239 51 007 - 52 239 11 -6 1 22 - "- - - -" - - 127 717 12 -7 -2 24 - 139 320- - - - "- - 139 320 13 -4 0 22 * 127 710 24 464 103 246 51 007.-52 239 51 007 - 52 239 14 -6 1 23 * 133 515 25 576 107 937 49 561. -58 377 49 561 - 58 377 15 2 2 19 * 110 295 21 128 89 167 55 344. -33 823 55 344 - 33 823 16 5 6 14 - 81 270 - - - - "- 14 400 62 550 17 4 8 14.

   "- - - - 62,055 - 110,250 - 18 6 10 14 -" - - - - 135,225 - 118,800 - 19 6 11 12 - 69,660 - - - - 109,635 - 33,900 - 20 1 7 16 - 92,880 - - - - 194010 - 136,350 - 21 9 11 10 - 58,050 - - - - 355,335 - 169,650 - 22 13 14 7 - 40,635 - - - - 477,600 - 162,900 - 23 11 12 9 - 52,245 - - - - 528,867 - 79,620 - 24 4 6 15 * 87,075 16,680 70395 61126. -9269 519598 61126 - - 25 5 9 13 * 75465 14456 61009 64017. 3009 522607 64017 - - 26 7 8 12 - 69660 - - - - 585157 - 101 700 - 27 5 8 14 - 81 270 - - - - 661 284 - 121 075 - 28 7 9 12 - 69 660 - - - - 750 000 - 124 107 - 29 8 12 Il - 63 855 - - - - "- 49 119 - 30 4 8 14 - 81 270 - - - - 709 485 - 31 350 - 31 3 6 13 - 75 465 - - - - 652,740 - 14,400 - 2,827,035 509,658 1,267,615 1,095,296,404 liters fuel 8.15 E 23.18 E 17.55 ± 150.17 ± total = 48.88 ± JANUARY date heap 2 t SP pl p2 F in St.

   Stock Fx Air RAF 652 740 1 4 8 14 - 81270 - - - - 587 070 - 12 000 - 2 2 6 16 - 92 880 - - - - 494 190 - - - 3 0 4 18 - 1 044 - - - - 491 587 - 78 375 - 4 6 6 14 - 81,270 - - - - 572,362 - 124,650 - 5 8 10 11 - 63,855 - - - - 678,157 - 130,500 - 6 7 8 13 - 75,465 - - - - 643,447 - 31,350 - 7 3 6 16 - 92,880 - - - - 550,567 - - - 8 2 7 15 - 87 075 - - - - 590 723 - 97 870 - 9 5 8 14 - 81 270 - - - - 525 053 - 12 000 - 10 2 6 16 - 92 880 - - - - 432 173 - - It -1 4 18 - 104 490 - - 327 683 - - 12 4 6 15 - 87 075 - - - - 240 608 - - - 13 3 5 16 - 92 880 - - - - 147 728 - - - 14 1 7 16 - "- - - - 182 079 - 97 870 - 15 5 8 14 - 81,270 - - - - 116,409 - 12,000 -

  <Desc / Clms Page number 9>

 16 2 4 17 - 98 685 - - - - 17 724 - 17 4 7 15 - 87 075 - - - - 57 840 - 97 870 - 18 5 8 14 - 81 270 - - - - 0 - 12 000 7 790 19 2 5 17 - 98 685 - - - - - - - 98 685 20 3 3 17 * 98 685 21 267 77 418 62 640. -14 777 - 62 640 - 14 777 21-4 0 22 *

  12771027522 100188 54509. -45679 - 54509 - 45679 22 -7 -2 24 * 13932030024 109216 51256. -58040 - 51256 - 58040 23 -6 0 23 * 133515 28773 104742 52883. -51859 - 52883 - 51859 24 -7 2 23 * "" "" "" "25-4 3 21 * 12190526271 95634 56135.-39499 - 56135 - 39499 26 1 7 16 - 92880 - - - - - 14400 74 160 27 3 9 14 - 81 270 - - - - - - - 81 270 28 -1 2 20 * 116 100 350 520 91 080 57 762.-33 318 - 57 762 - 33 318 29 -2 7 23 * 13 331 528 773 104 742 52 883. -51859 - 52 883 - 51 859 30 -3 1 22 * 12 771 027 522 100 188 54 509. -45 679 - 54 509 - 45 679 31 - 1 0 21 - 121905- - - - - - - 121905
3105675 495460 720855 776379
444 liters fuel 7.93 # 13.16 # 12.44 #
164.97 ± total = 33.53 #
FEBRUARY date t 1 t 2 t S P pl p2 F at St.

   Stock Fx Air RAF 1 -4 0 22 - 127 710- - - 0- - - 127 710 2 4 3 17 - 98 685 - - 98 685 3 6 5 14 - 81 270 - - - - 48 470 - 99 800 - 4 7 7 13 * 75 465 18 070 57 393 87414.30019 78489 87414 - - 5 5 9 13 - 75465 - - - - 91 164 - 67 800 - 6 4 10 14 * 81 270 19460 61 810 85 607.22797 113961 85607 - - 7 2 11 13 * 75 465 18 070 57 395 87414.30019 143977 87414 - - 8 -1 10 15 * 87,275 20,850 66,225 83,800,175,775 151,552 83,800 - - 9 4 7 14 * 81,270 19,460 61,810 85,607.23797 183,349 85,607 - - 10 2 9 15 - 87,075 - - - - 236,035 - 105,970 - 11 5 7 14 - 81,270 - - - - 332,029 - 136,350 - 12 9 15 8 * 46440 11 120 35 320 96 449.61129 393 149 96 449 - - 13 8 10 11 - 63 855 - - - - 392 461 - 48 590 - 14 3 8 15 * 87 075 20 850 66 225 83800.17575 410036 83800 - - 15 9 10 10 - 58 050 - - - - 394951 - 33050 - 16 2 Il 13 * 75465 18070 57395 87414.30019 424970 87414 - - 17 0 7 17 * 98685 23630 75055 80187.5131 430101 80187 - - 18 -2 6 19 *

  110295-26410 83885 76572.-7313 422788 76572 - - 19-1 4 19 * "" "" "415 475 - - 20-3 6 20 - 116 100- - - - 299 375 - 21 1 8 15 - 87 075 - - - - 212 300 - - 22 -2 6 19 - 110 295 - - - - 120 725 - 14 400 - 23 4 7 15 - 87 075 - - - - 165 860 - 101 700 - 24 6 8 13 - 75 465 - - - - 166 471 - 58 520 - 25 4 12 12 * 69660 16680 52980 89221. 36241 202712 89221- - 26 5 13 11 * 63855 15290 48565 91028.42463 245175 91028 - - 27 3 14 12 * 69660 16680 52980 89221.36241 281416 89221- - 28 4 13 11 * 63855 15290 48565 91028.42463 3 16 12 * 69 660 16 680 52 980 89 221.36 241 360 120 89 221- -
2414880 1380555 666180 226395
345 liters fuel 22.14 E 12.17 # 3.62 ± 128.28 ± total = 37.93 ±

  <Desc / Clms Page number 10>

 
 EMI10.1
 MARCH date t 1 t 2 t S P pl p2 F at St.

   Stock Fx Air RAF 360 120 1 4 17 10 - 58,050 - - - - 428,222 - 97,040 - 2 3 16 11 - 63,855 - - - - 510,448 - 112,370 - 3 4 14 11 * 63,855 16,819 47,036 112,997. 65,961 576,409 112,997 - - 4 8 16 8 - 46440 - - - - 714 829 - 142 200 - 5 6 13 12 - 69 660 - - - - 750 000 - 62 777 - 6 5 15 10 * 58 050 15 290 42 760 114985.

   72225 42760 - - 7 6 14 10 * 58050 "" "" "" - - 8 8 16 8 - 46440 - - - - "- 35723 - 9 5 14 11 - 63855 - - - -" - 49 119 - 10 4 10 13 - 75465 - - - - 717 500 - 33050 - 11 2 11 14 - 81 270 - - - - 680 300 - 33 900 - 12 1 9 15 - 87 075 - - - - 730 986 - 105 970 - 13 5 11 12 - 69 660 - - - - 763 701 - 78750 - 14 4 9 14 - 81 270 - - - - 695 976 - 20900 - 15 2 13 13 * 75 465 19 877 55 588 109022x 53434 749410 109022 - - 16 5 16 10 * 58 050 15290 42760 114985x 72225 750 000 43 350 - - 17 7 15 9 * 52 245 13761 38484 116973x 78489 "38484 - - 18 9 14 11 * 63855 16819 47036 112997x 65961" 47036 - - 19 8 15 11 * "" "" "" "- - 20 7 12 11 -" - - - - "- 49119 - 21 9 11 10 - 58,050 - - - - "- 44,654 - 22 8 10 11 - 63,855 - - - -" - 49,119 - 23 6 9 13 - 75,465 - - - - 724,793 - 38,660 - 24 3 7 15 - 87,075 - - - - 750,000 - 86,370 - 25 5 7 14 - 81,270 - - - - 668,730 - "- 26 1 8 16 - 92,880 - - - - 651,926 - 58,520 -

  27 4 6 15 - 87 075 - - - - 564 851 - - - 28 3 8 15 - "- - - - 518 461 - 31 350 - 29 3 9 14 - 91 270 - - - - 446 239 - 6 960 - 30 0 6 17 - 98 685 - - - - 347554 - - - 31 3 10 14 * 81270 21406 59864 107034. 47170 394724 107034 - - 2194290 590479 1136551 313 liters fuel 9.47 # 20.75 # 116.55 # total = 30.22 # APRIL date tt 2 t SP p p2 F at St.

   Stock Fx Air RAF 394 724 1 3 8 15 * 87,075 22,935 64,140 125,242. 6,102 455,826 125,242 - - 2 6 9 13 - 75,465 - - - - 430,619 - 38,660 - 3 3 12 13 * 75,465 16,877 55,588 129,217. 73,629 504,248 - - - 4 2 13 14 * 81270 21406 59864 127230. 67366 571614 - - - 5 3 12 13 * 75465 19877 55588 129217 73629 645243 - - - 6 2 10 14 * 81270 21406 59864 127230.

   67 366 712 609 - - - 7 7 12 11 - 63 855 - - - - 750 000 - 77 881 8 8 16 8 * 46 440 12 232 34 208 139 156 x 104 948 "34 208 - - 9 4 18 9 * 52 245 13761 38 484 137 168 x 98 684" 38 484 - - 10 5 21 7 * 40638 10703 29933 141440x 111212 "29932 - - 11 7 24 4 * 23220 6116 17104 147106x 130002" 17104 - - 12 4 18 9 * 52245 13761 38484 137168x 98684 "38484 - - 13 3 10 14 - 81270 - - - -" - 62,515 - 14 7 9 12 - 69,660 - - - - "- 53,584 - 15 6 7 8 - 46,440 - - - - 722,280 - 14,400 -

  <Desc / Clms Page number 11>

 
 EMI11.1
 16 3 6 16 - 92880 - - - - 629 400 - 17 2 12 13 - 75 465 - - - - 733 935 - 136 000 - 18 8 16 8 - 46 440 - - - - 750 000 - 48080 - 19 10 14 8 - "- - - - "- 35720 - 20 4 20 8 * 46440 12232 34208 139156x 104498" 34208 - - 21 7 18 7 * 40635 10703 29932 141144x 111212 "29932 - - 22 5 16 10 - 58 050 - - -" - 44653 - 23 9 15 8 - 46440 - - - - "- 35723 - 24 6 18 8 * 46440 12232 34208 139156x

  104498 "34208 - - 25 8 20 6 - 34890 - - - -" - 26792 - 26 9 21 5 29025 7645 21380 145120x 123739 "21380 - - 27 8 14 9 - 52245 - - -" - 40188 28 7 10 12 - 69660 - - - - "- 53584 - 29 5 8 14 - 81270 - - - -" - 62515 - 30 4 12 12 - 69660 - - - - "- 53584 - 1787940 403182 783879 255 liters fuel 6.44 E 14.32 E 94.96 ± total = 20.76 ± MAY date tOI t 2 t SP pl p2 F at St.

   Stock Fx Air RAF 750,000 1 6 8 13 - 75,465 - - - - "- 58,050 - 2 5 10 13 -" - - - - "-" - 3 7 20 7 - 40,635 - - - - "- 31,257 - 4 4 16 10 58 050 15290 42760 148700x 105940 "42760 - - 5 8 18 7 - 40635 - - - -" - 31257 - 6 10 22 4 23220 6116 17104 160627x 143523 "17104 - - 7 9 15 6 34830 9174 25656 156651x 130995" 25656 - - 8 8 12 10 - 58,050 - - - - "- 44,654 - 9 6 9 13 - - - - - -" - 58,050 10 5 11 12 - 69,660 - - - - "- 53,585 11 7 9 12 -" - - - " Il 12 8 16 8 46 440 12232 34208 152676x 118468 "34208 - - 13 10 24 3 17465 4587 12828 162614x 149786" 12828 - 14 9> 30 0 - - - - "- - - 15 6 16 9 52245 13761 38484 150688x 112204" 38484 - - heating off 16 10 24 3 * 17 465 - - - - 732 535 - - - 17 9 26 3 * "- - - - 715070 - - - 18 10> 30 0 * - - - -" - - - 19 15 28 0 * - - - - - "- - - 20 14 26 0 * - - - - -" - - - 21 15 27 2 * 11 610 - - - - 598 970 - - - 22 14 28 0 * - - -

  - - "- - - 23 16 26 0 * - - - - -" - - - 24 14 24 1 * 5805 - - - - 593 165 - - - 25 16> 30 0 * - - - - "- - - 26 18 22 0 * - - - - - "- - - 27 16> 30 0 * - - - - -" - - - 28 17 27 0 * - - "29 15> 30 0 - - - - -" - - - 30 16> 30 0 - - - - - "- - - 31 14" 0 - - - - - 593 165 - - - 789 484 171 040 388 488 113 liters fuel 2.73 E 7.09 E 41.94 ± total = 9.82 ±

  <Desc / Clms Page number 12>

 Solar heat recovery and storage
In the strongly glazed rooms of the house, the heat is concentrated under the ceiling, and as we have seen is absorbed by an exchanger located at this level. Various types of exchangers can be used: flat exchangers fixed under the ceiling, or better joists or hollow metal slabs in which the water carrying calories will circulate.



   If joists or slabs are used, these will serve as load-bearing elements; these will be joists for a ceiling with exposed joists or slabs for a flat ceiling. While capturing the heat, they will at the same time produce the cold necessary to return to the comfort temperature that we assume everywhere constant and equal to 20. In reality, this temperature will be adjustable for comfort but for the ease of calculations we assume that the temperature remains constant throughout the house and throughout the year.



   For the heat exchange, the metal matters little because it is limited by the transfer coefficient at the metal-ambient air interface which is here 7 kCal.



   If we use steel joists (tubes of rectangular section) of for example 10 cm wide and 20 cm high at the rate of two joists per m and for a sheet thickness of 1.5 mm: a joist of a length 4 m will weigh 28 kg.



  For a uniformly distributed load of 500 kg over a length of 4 m, these dimensions are suitable, with a slight reinforcement, as a basis for calculation and we will use them for the following calculations.



   Two joists per m will require around 60 joists for sunny rooms, with a total length of 30 m.



   The useful exchange surface per joist is 0.5 * 4 = 2 m2 and a total of 120 m2.



   The previous tables show that overall, if we except the excess heat, we must be able to store 90,000 kCal in 11 hours of sun: (ES - pl).



   With an exchange coefficient of 7, the temperature difference between incoming and outgoing water must be greater than 90,000 / 120 * 7 * 11 = 9.7. However, we have seen that the temperature difference in the accumulator can vary between -3 and 25, an average temperature of 14. The surface of the joists will therefore be sufficient.

   The volume of the accumulator will then be 90,000 / 28 = 3,214 liters
We will take a volume of 5 m3 - "an interest, which goes beyond the scope of this study is the possibility of obtaining a cheap fire-fighting device by placing fusible tablets or bulbs filled with a boiling liquid at low temperature under joists or slabs according to known and used processes. "
In this case, a pressure switch control will increase the flow and pressure to obtain the desired efficiency. If necessary, the volume of the heating circuit can be added to reach a total volume of 35 m3.



  Heating circuit
The home heating circuit must be able to store all the excess calories supplied by the heat pump.



   To store these calories, instead of using a large tank and supplying radiators, it is much more advantageous to store the heat in bulky convectors which will then redistribute this heat.



   These convectors can completely replace the interior walls. They will simply consist of a rectangular tank 15 to 40 cm thick enclosed between two partitions spaced a few cm from the tank, depending on the architecture of the buildings. Openings in the bottom and top of the partitions will release convection heat.



   Thus the possible volume for the pilot dwelling with prefabricated convectors (tanks 20 cm thick) and 3 different lengths (1) (2) (3) allows to reach a volume of 26.2 m3 (Fig. 6 ).



   If joists are also placed in non-sunny rooms (load-bearing or fire-resistant elements) they will also be used for heating and will increase the volume by 20 * 2 * 80 = 3,200 liters: in total a circuit of 26.2 + 3 , 2 to which we will add the volume of the pipes to arrive at the volume of 30 m3
By these joists, there is a radiant heating from the ceiling, making the temperature more homogeneous and eliminating the effects of cold windows, resulting in increased comfort. We will first use the radiant heat from the joists here and will supplement, by regulation, the heat emitted by the convectors.



   In this way, the radiant joists deliver a fixed quantity of heat in relation to the temperature of the circuit, and the convectors supplement to reach the desired comfort temperature.



   This principle is applicable to rooms with large bay windows, in the absence of sun, by a set of solenoid valves, the joists will produce the same effect - or another combination (see below).



   The maximum temperature at the outlet of a heat pump is limited to 50 and since the minimum heating temperature will subsequently be calculated sufficient to 25, the temperature of the water in the circuit varying between 25 and 50, the quantity of possible heat being able to to be stored in the pilot dwelling is 30,000 * 25 = 750,000 k Calories.



   It will be shown later that this stock is sufficient.



   Note that it is possible to double this stock by replacing all or part of the exterior walls with convectors.



  B - Energy removed from the air.



   In the absence of sunlight, it is possible to remove heat from the air when the outside temperature is sufficient.



  The air temperature at the outlet of an exchanger must still be 2.5 in order to avoid icing of the fins (drop in efficiency).

  <Desc / Clms Page number 13>

 



   At the entrance, the air temperature will be higher than 5 to obtain a valid exchange. In our case, the heat is transferred to the brine from the heat pump evaporator.



   Exchange capacity The amount of heat transferred is: Q = K * S * Ùm with: K, the exchange coefficient
S, the exchange surface Ùm, the average temperature
The exchanger must be able to extract a still significant amount of heat at low temperature. At the lowest temperature, the air enters at 5 and leaves at 2.5. The brine which arrives against the current of air will be given a negative temperature to have a sufficient difference.



   According to daily records, the maximum amount of calories to be supplied by the heat pump in 9 hours is 180,000 kCal .; which requires 180,000 / 1.3 = 138,500 kCal. at the exchanger, this for higher temperatures, and reduced to 95,000 kCal for temperatures close to 5 to 6.



  As a precaution we will take 120,000 / 9 = 13,300 kCal. per hour.



  For a reasonable brine flow rate of 2 m3 / hour, the outlet temperature will be increased by: 13,300 / 2000 = 6.6.



   The average exchange temperature (calculated according to Hausbrand):
Air 5 brine 0.6 difference dl = 4.4
2.5 -6 the difference d2 = 8.5
The ratio dl / d2 = 0.51 and after correction, according to Hausbrand, drops to 0.73
The average exchange temperature is 0.73 * d2 = 0.73 * 8.5 = 6.2
The exchanger to be used must have a K * S of 13.300 / 6.2 = 2.145.



  Among those in trade, we find the following:
Characteristics given by the manufacturer.



  Tubes of steel 25 mm in diameter and fins in sheet metal set with 7 * 7cm spaced 5 mm in 4 rows Dimensions: height 0.98m; width 0.84; thickness 0.36 Exchange surface = 75 m2 and free cross section = 0.36 m2 Characteristics depending on the air flow speed
Speed flow pressure drop coeff. transfer 4 mls 1.4m3 / s 5 mm of water 20
6 2.2 8 26
8 2.9 12 28 The efficiency of these devices is on average 65% in new condition
The exchange surface being 75 m, K must be equal to 2.145 / 75 = 28. We will therefore pass the air at the speed of 8 m / s for the minimum temperature of 5.



  Amount of heat supplied as a function of the outside temperature.



   For the brine temperature of -6 and the air speed of 8 m / s., The exchange capacity is 13,300 kCal / h, but the heat removed from the air is lower and equal to: 2.9 (m / s) * 3,600 * 1.2 (air density) * 0.3 (specific heat humid air) * dt or 3.758 * dt with (dt = 5 - 2.5) therefore 3.758 * 2.5 = 9.400 kCal./h.



   The exchange power is too high. We can raise the brine temperature to -3 and settle for a value close to 9.400 kCal. The new Ùm becomes:
5 1 dl = 4 # #
2.5-3 d2 = 5.5 dl / d2 = 0.72 corrected = 0.84 Ùm = 0.84 * 5.5 = 4.6.



  The exchange capacity is 28 * 759 * Ùm = 2.100 Ùm = 2.100 * 4.6 = 9,660 kCal (more in agreement with the heat subtracted from the air).



   For an air temperature of 7 7 1 dl = 6 # #
3.5-3 d2 = 6.5 dl / d2 = 0.97 and Ùm = 6.5 * 0.92 = 6.3 The exchange capacity is 2.100 * 6.3 = 13.230 kCal The heat subtracted from air = 3758 * 3.5 = 13.153 kCal
For an air temperature of 10
10 2 dl = 8 # #
5-3 d2 = 8 Ùm = 8 The exchange capacity = 2.100 * 8 = 16.800 kCal The heat withdrawn from the air = 3.

   758 * 5 = 18,790 kCal
For an air temperature of 15
15 5 dl = 10 # #
7-3 d2 = 10 Ùm = 10 The exchange capacity = 2.100 * 10 = 21.000 kCal The heat subtracted from the air = 3.758 * 8 = 30.064 kCal
Note that we gradually raise the temperature of the air at the outlet to avoid icing (with the temperature, the air becomes more and more humid)

  <Desc / Clms Page number 14>

 
The curve (Fig. 13) gives the calories supplied as a function of the outside temperature.



  The brine flow rates as a function of the external t: 5 9,660 / 4 = 2.4001 / h
7 13.230 / 4 = 3.3001 / h
10 16.800 / 5 = 3.3001 / h
15 21,000 / 8 = 2.6001 / h We therefore choose with this type of exchanger: an air speed of 8 m / s. a brine temperature of -3 a brine flow rate of 3.3001 / h.



  Under these conditions, the electric power is # W = Q * h / 0.65 * 75
With W the horsepower h the pressure drop in mm of water
0.65 yield
75 to convert kgm / s to CV In our case: W = (2.9 * 12) / (0.65 * 75) = 0.71 CV or 525 Watts Spending on the day = 0.525 * 0.155 E = 0.081 E (3.3 Fb). at night = 0.525 * 0.056 E = 0.029 E (1.2 Fb). for an average temperature of 7 to supply 13,200 kCal and for 10,000 kCal during the day 0.062 # (2.5 Fb) at night 0.022 E (0.9 Fb)
Note that we have carried out these calculations, with this type of exchanger as a basis, since we have the characteristics of the entire series manufactured by the Cie Générale d'Hygiène in 1950;

   but this type of iron exchanger is not very suitable for us because of the condensation of water vapor and the risk of rust when crimping the fins reducing the conductivity. In addition, the high speed of the air preferably requires an exchanger composed of copper tubes with also welded copper fins for better exchange at low temperature, or another more efficient.



   So far, we pass the brine through the evaporator of the heat pump for the simplification thereof and the possibility of using the exchanger to reintroduce calories into the soil; but we can advantageously create a bypass of the refrigerant towards the exchanger for a better efficiency.



   As in our region, it will ultimately be necessary to use little energy from the ground (the following calculations will demonstrate this), we are adopting this second solution for our pilot home.



  Distribution of temperatures over a 24-hour day. (From 7 a.m. to 7 a.m. the next day.)
The lowest temperature is in the morning at daybreak. It gradually increases until 4 p.m. to 5 p.m., has a plateau, then decreases fairly regularly until the next morning.



   We recorded the temperatures in the morning "t 1" between 7 and 8 h. and in the afternoon "t 2" between 4 and 5 pm. The temperature curves recorded during the day and at night show rise and fall sometimes slightly concave, sometimes slightly convex according to the climatic variations of the moment; on the whole we can consider these curves as straight lines.



  Heat removed from the air.



   As with solar energy, the heat removed from the air during the day poses a problem because of the price per kW. If one can easily store the solar heat in AC, it is not the same for the heat extracted from the air because the temperature of the brine is too low. It is best to remove the heat from the air first after 10 p.m.



   Exchanger and heat pump operate on the night current. However, we reserve the right to recover heat from the air during the day when geothermal energy is not possible. This heat coming back cheaper than electric heat at night.



   Heat recovered as a function of temperatures. (Fig. 14): t l, t 2 and t 3 (note that t 3 is the temperature t the next morning). In the majority of cases t 2 is greater.



   During the day, the exchanger operates as soon as the outside temperature reaches 5. It is this temperature which controls the start-up of the exchanger and the heat pump.



  The amount of heat recovered up to 16 hours corresponds to the hatched zone A and dj 1 is the operating time of these devices.



  We have the relation dj1 / (t 2-5) = 9 / (t 2 -tl) and dj1 = 9 (t 2 - 5) / (t 2 - t 1) The average temperature is t mj1 = (t 2 + 5) / 2.



   The amount of heat obtained per hour as a function of the outside temperature is indicated on the previous curve. (Fig. 13)
For a run time djl, the total quantity transferred to the heat pump by the exchanger is the product of these two values. To find out the amount of heat transferred by the exchanger between 4 and 10 p.m. , the operating time and the average temperature will be calculated in the same way.



   At night, the heat exchanger and heat pump operate from 10 p.m. t 4 = 0.6 t 2 + 0.4 t 3 The duration dn = 15 (t 4- 5) / (t 2 -t 3), and the average temperature (t 4 + 5) / 2 When t 2 and t 3 are> 5, dn (the operating time) is 9 h.



  And when t 2 <t 3, dn = 15 (t 3- 5) / (t 3 -t 2) Average temperature: (t 4 + 5) / 2 or (5 + t 3) / 2 depending on whether t 4 is> or <to 5.

  <Desc / Clms Page number 15>

 



   The following table shows us the quantities of heat extracted at night by the exchanger as a function of the outside temperatures: t 2 and t 3: t 3 -3-2 -1 0 1 2 3 4 5
 EMI15.1
 ---. ----- ¯ ¯ ¯ ... -----------------...--------------- --------------... --- ...------- t02 --- ¯.¯¯, .. ¯¯¯¯¯¯¯¯¯¯ ¯¯¯¯¯¯¯¯¯.

   ¯.¯¯¯¯¯w¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯.w¯¯¯¯¯¯¯ 5 6 14,400 94,050 7 14,400 41,800 97,870 8 4,110 12,000 31,250 10,500 9,660 19,855 20,900 38,660 67,800 10,950 10,550 15,750 26,590 110,595 11,450 17,980 22,990 33,900 45,220 64,300 78,550 11,350 12,350 16,500 27,300 38,420 55,120 7,260 29,900 36,750 48,100 66,000 66,400 81,300 103,880 126,100 15 27,400 35,800 42,830 53,600 66,840 73,160 89,170 107,870 127,570 16 32,900 41,800 48,900 59,100 69,250 80,330 97,040 112,370 130,500 t 3 6 7 8 9 10 11 12 13 14 t 2 -2 19,590 37,660 54830 126,400 137,320 -1 22,800 43050 61,450 80,000 92,500 105,010 120,565 136,125 0 26,125 48,430 68,060 88,000 103,380 118,640 132,240 1 32,660 57,970 77,130 96,490 113,260 130,500 2 39,190 67,410 86,200 104,480 119,200 133,425 3 58,780 76,910 95,600 115,000 125,670

  100,600 124,630 130,570 5,94050 99,800 105,520 121,725 135,460 6 97,870 114,500 124,535 7 101,700 117,800 127,570 13,650 8,110,221 121,775 131,950 139,800 9 113,850 125,800 136,350 10,118,500 130,500 138,000 11,124,650 133,700 13,12670
Calories extracted from the air as a function of t 2 and t 3 C - Other sources Only the sun and the air.



   If it is not possible to extract enough heat from the sun and the air, we will go to the following sources and in order: 1 - heat from the ground
2- the heat of the air during the day directly passing through the heat pump in the heating circuit
3 - finally the electric heat.



   1 - Calories that can be removed from the ground.



   When the ground allows it, no rocks and sufficient space around the house, we can use geothermal energy and even go further than the use which makes it, not only use the ground to extract its calories, but to house them. As in certain periods of winter the temperature is sufficient, an exchanger connected to the transfer circuit will be used to re-inflate the floor provided that the floor temperature is lower than the outside temperature.



   In normal operation, the heat from the ground will be taken directly at night from the transfer circuit and the heat pump.



  2 - Calories that can be removed from the iour by the heat pump.



   We have seen that it is possible to remove heat from the air during the day between 7 a.m. and 10 p.m. by the heat exchanger and the heat pump (this quantity is greater than that withdrawn overnight), but at a price three times higher.



   All these technical complications are due to the difference in price per kWh between day and night, but when this process is sufficiently developed, we can expect a lesser difference, hence the simplicity: of AC and a single circuit ... ... It's not for tomorrow .



  3 - Electrical energy: Usable when other means are exhausted.

  <Desc / Clms Page number 16>

 



  Distribution of different energies
So far, we have treated in the previous monthly tables only losses and the incidence of solar energy (see from page 6) As a reminder:
P the calories lost by the entire building in 24 hours and depending on the outside temperature P =
5805 ¯t. pl the calories lost during the periods of sun in the sunny parts of the house. p2 the remaining loss (P-pl)
F the calories transferred by the heat pump.



   At St the amount of excess heat to be stored in the heating circuit.



  With the new data on the other complementary energies, we add to these tables:
St the stock at the end of the day (the next morning at 7 am) i.e. the amount of heat present in the heating circuit.



   Fx calories from solar energy actually used
Air the calories removed from the air at night.



    RAF the rest of the calories to supply and in order: geothermal energy, air during the day, finally electric.



  Price comparison of these different sources
For 10,000 kCal required for heating, you must spend with: 1 Lefuel a) new high-efficiency boilers (100%) 1 liter at 0.37 # 0.37 # b) fireplaces and boilers currently in service whose efficiency is estimated at 70%: 1.43 1. 0.53 # 2 Solar heat: for 10,000 kCal to be supplied PAC output 2.84 * 0.056 # = 0.16 #
3 The heat removed from the air after 10 p.m. and transferred directly by the heat pump = 0.159 + 0.022 = 0.18 # 4 Geothermal energy:

   the heat is captured from the ground by the transfer circuit at night and transmitted by the heat pump 0.16 # 5 The heat is removed from the air during the day and transmitted directly by the heat pump: exchanger during the day = 0.06 # heat pump = 2.84 * 0.155 # = 0.44 ± total 0.50 # 6 Electric heating at night: 11.63 kW 0.66 #
In these calculations, we do not take into account the very low energy consumed by the circulation pumps.



   As long as the pressure drops are respected, consumption is around 20 Watts for a flow rate of 1,000 liters per hour.



  Application to the process
In our region, from September 15, we observe slightly larger temperature differences, but above all oscillating around a declining temperature. For average temperatures reduced to around 16 and 14 already, these differences become harmful to health: colds, flu, etc. We have every interest in putting the process into service to stabilize the temperature in the home as quickly as possible, thanks to the thermal inertia of all the convectors which is 2.5 times greater than that of brick walls ( the specific heat of the water is 1 for a density of 1, while the specific heat of the brick is 0.2 for a density close to 2).



   In addition, the rate of heat diffusion is much faster (7 times based on the transfer coefficients). During this period, only solar heat will be captured, it will gradually raise the temperature of the heating circuit so that on October 1 we are left with a temperature of 40 corresponding to a stock of 450,000 kCal necessary to compensate for low temperatures encountered in some years in early October. (but becoming increasingly rare).



   In September, the temperature is raised from 20 to 40. You have to supply (40 - 20) * 30,000 = 600,000 kCal for a price of 600,000 * 0.16 / 10,000 = 9.62 # (388 Fb).



  Heating year from October 1991 to May 1992 Month of October. (see page 6) - On October 1 at 7 am, the stock in the heating circuit is 450,000 kCal.



   The sun is shining and providing ES - pl = 110,890 - 8,340 = 102,550 kCal. These calories are stored in AC whose maximum capacity is 28 * 5,000 = 140,000 kCal
This heat is transferred by the heat pump after 22 hours in the heating circuit equal to 102,550 * 1.3 =
133.315 (column F) minus the loss p2 i.e. 133.315 - 26. 490 = 106.825 (column: at St.).



   The stock in the heating circuit amounts to 450,000 + 106,825 = 556,825 kCal.



   - "In column F, we follow 133.315 with a point to indicate that all solar energy has been used and report this value in column Fx: (solar heat actually used); and follow with a cross when only part of it is used "- - On October 2 in the morning, there are no more calories in AC and the brine has dropped to -3.



   The solar heat is entirely captured by AC, the quantity to be stored (F - p2) is 88,159 kCal which brings the stock to
644. 984 kCal.



   - On October 3, same, the stock goes to 739,365 kCal.



   - "Note that we are talking about heat stored in AC and heat stored in the heating circuit." -

  <Desc / Clms Page number 17>

   - On October 4, the amount of heat to be stored is 100.603 kCal.



  The CAP will not provide this quantity because the stock becomes maximum. the thermometer thc reaches 50 and cuts the current of the heat pump; but only 750,000 - 739. 365 plus the loss p2 will be used = 41,540
It remains in AC 110890-9730-41540 = 59620 (which can be found at the top of AC).



  "The PC will control the heat pump at night so that the heat contained in AC is removed before the air heat - On October 5, no sun, the heat is removed from the air at night, the temperatures are: tl = 9; t2 = 22; t3 = 13. The temperature being> 5, at 10 p.m., the exchanger and the heat pump are activated, for these temperatures, the table (page 15) indicates that the exchanger can extract more than 136,000 kCal (exchanger limit, imposed by the heat pump) The heat pump will supply the entire loss P = 23,220 and the heat exchanger 23,220 / 1,3 = 17,861 kCal which is entered in the Air column.



   Thus, on October 5, the 23,220 kCal that the PAC must supply corresponds to 17,861 kCal to be withdrawn from AC. 59,620 - 17,861 = 41,759 kCal will remain
October 6 AC arrives at its maximum stock (140,000 kCal) and will remain there until 16. In reality, we remove more calories from the sun than the calculations will indicate later, but given the small difference in the cost price between the solar energy and that of air, one does not take into account here in these calculations of the residual energy contained in AC, the error being very weak and the calculations already rather consequent. The calculation will be as follows: - On October 6, the sun returns and the heat pump provides the equivalent of the loss p2: = 13,245 kCal On the following days until October 16, the sun continues to provide the equivalent of p2 each day .



  - On October 17, the sun is over, the heat is taken from the air at night. tl = 6; t2 = 16; t3 = 5.



   At 10 p.m., t4 = 0.6 * 16 + 0.4 * 5 = 11.5; the duration dn is 9h. (since t2 and t3 are> 5) and the average temperature = (11.5 + 5) / 2 = 8. The heat capacity of the exchanger = 14,500 * 9 = 130,500 (see the table which gives these values directly on pages 13). The heat pump will provide the equivalent of the loss p2 = 52,245 and the exchanger only 52,245 / 1.3 = 40,188 kCal.



    - October 18: tl = 5; t2 = 12; t3 = 4 # t4 = 0.2 * 12 + 0.4 * 4 = 8.5, dn = 15 (8.5 - 5) / (12 - 4) = 6.5 hours of walking, the average temperature of : + 5) / 2 = 6.5. The heat capacity of the exchanger is: 12,250 * 6.5 = 79,620 (see table), but will only provide 63,855 / 1.3 = 49,119 kCal.



  - October 19, tl = 4; t2 = 14; t3 = 3. The table indicates a heat capacity of 81,300, but should only provide 63,855 / 1,3 = 49,119 kCal.



  - On October 20, the capacity of the exchanger is 38.420 and after PAC: 38.420 * 1.3 = 49.946 kCal
The loss is higher = 75,465; the shortfall is drawn from the stock, which drops to 750,000 - 75,465 + 49. 946,724,481 kCal
As long as the temperature in the heating circuit is> 25 the PC does not allow heat to be removed from another source than that of the sun and the air "- - October 21, same, the capacity of the exchanger = 48.590 and after PAC = 63.167 we call up the stock again 724.481- 87. 075 + 63.167 = 700.573 kCal.



  - On October 22, the capacity of the exchanger = 76.560 and after PAC = 99.531; the stock goes up: 700,573 - 81,270 + 99,531 = 718,834 kCal.



  - On October 23, the capacity of the exchanger = 131,750 and after PAC = 169,650; however, the heat pump must only supply: 750,000 - 718,834 + 75,465 = 106,631 and the heat exchanger at the heat pump: 106,631 / 1,3 = 82,023 kCal - The rest of the month, the capacity of the heat exchanger is more than sufficient.



  The sun supplies 776,820 kCal for a price of 12.44 # (502 Fb).



  Air 598. 355 10.93 E (441 Fb). in total 23.37 # (943 Fb).



  If we had used fuel oil we would have needed 200 liters for 74.36 # (3.000 Fb).



  November month.



   On November 1, the stock is 750,000 kCal and no sun. The capacity of the exchanger is more than sufficient and provides only 52,245 / 1.3 = 40,188 kCal.



   Thereafter, these are still the same calculations as in October The sun provides 462,898 kCal at a cost of 7.41 # (299 Fb).



  Air 1,022,828 18.69 # (754 Fb). in total 26.10 # (1.053 Fb).



  If we had used fuel oil 130.44 # (5.262 Fb).



  December month.



   The stock is 98.652 kcal, the temperatures are too low and no sun, the stock drops to 0, the temperature of the heating circuit reaches 25 "At this moment the current is connected to the other sources" -
RAF amounts to 110,295 - 98. 652 = 11,643 kCal.



  The other days until the 15th, little sun and temp. are too low, the system uses other sources (RAF)
From the 16th, it is mainly the air that provides heat, the stock goes up.



  The sun provides 509,658 kCal. at a cost of 8.15 # (329 Fb).



  Air 1,267,615 23.18 # (935 Fb). in total 31.33 ± (1.264 Fb).



  RAF by geothermal energy 17.55 # (708 Fb). with heat exchanger and PAC 55.23 ± (2.228 Fb). with electric heating 71.99 # (2.904 Fb).

  <Desc / Clms Page number 18>

 



  From where. the three possible processes.



  Process A (with geothermal) 31.33 + 17.55 = 48.88 # (1,972 Fb).



  Process B (aeroth + PAC on the day) 31.33 + 55.23 = 86.56 ± (3,492 Fb).



  Process C (electric heating) 31.33 + 71.99 = 103.32 # (4,168 Fb).



  If we had used fuel the cost 150.17 ± (6. 058 Fb).



  Month of January.



   At the start the stock is 652,740 Kcal, no sun until the 19th, the heat is removed from the air but insufficient, it is especially the stock which supplies until the 18th.



   Afterwards the sun reappears but insufficient it is RAF which provides the rest.



  The sun provides 495.460 kCal at a cost of 7.93 E (320 Fb).



  Air 720.885 13.16 # (531Fb). in total 21.09 ± (851 Fb).



  RAF by geothermal energy 12.44 # (502 Fb). aeroth + heat pump on day 39.07 # (1.576 Fb). electric heating 51.02 E (2.058 Fb).



  Method A 21.09 + 12.44 = 33.53 ± (1.353 Fb).



   B 21.09 + 39.07 = 60.16 # (2,427 Fb).



   C 21.09 + 51.02 = 72.11 # (2.909 Fb).



  If we had used fuel oil the cost = 164.97 # (6. 655 Fb).



  February month.



   The 1 and the 2, no sun and insufficient air temperature it is RAF which provides the heat
On the 3rd, the exchanger provides heat and stores 48,470 kCal.



    The rest of the month: and air is enough, on the 29th, the stock rose to 360 120 kCal.



  The sun provides 1,380,555 kCal at a cost of 22.13 # (893 Fb).



  Air 666.180 12.17 # (491 Fb). in total 34.30 # (1.384 Fb).



  RAF supplies 226,395 kCal by geothermal energy 3.62 # (146 Fb). aeroth + heat pump on day 11.38 # (459 Fb). electric heating 14.87 # (600 Fb).



  Process A 34.30 + 3.62 37.92 ± (1,530 Fb).



   B 34.30 + 11.38 = 45.68 # (1.843 Fb).



   C 34.30 + 14.87 = 49.17 # (1.984 Fb).



  If we had used fuel oil 128.28 # (5. 175 Fb).



  March
On the 1st, the stock is 360,120 kCal. Sun and air at night are enough. The sun provides 590.479 kCal at a cost of 9.47 # (382 Fb).



  * Air 1,136,651 20.75 E (837 Fb). in total 30.22 ± (1219 Fb).



  NO RAF If 116.56 ± (4,702 Fb) fuel was used.



  April
Sun and air are enough The sun provides 403,182 kCal at a cost of 6.45 # (260 Fb).



  Air 783.879 14.33 ± (578 Fb). in total 20.78 ± (838 Fb).



  If we had used fuel 94.97 ± (3.831 Fb).



  May
From May 15 everything is stopped except the circulation pump of the heating circuit which will stop on the 31st in order to exhaust the calories in stock.



  The sun provides 171,040 kCal at a cost of 2.73 # (110 Fb).



  Air 388. 488 7.09 E (286 Fb). in total 9.82 ± (396 Fb).



  If we had used fuel oil 41.94 ± (1.692 Fb).



  IN SUMMARY: Over the year the% brought by the sun, the air and RAF month Oct. Nov. Dec. Jan. Feb. March Apr May Sun 56 31 18 25 56 35 34 31 Air 44 69 44 36 29 65 66 69 RAF 0 0 38 39 15 0 0 0

  <Desc / Clms Page number 19>

 
 EMI19.1
 
 <tb> Price, <SEP> according to <SEP> the <SEP> solution <SEP> adopted <SEP>. <September>
 <Tb>
 <Tb>
 <Tb>
 <Tb>



  Month <SEP> Oct. <SEP> Nov. <SEP> Dec. <SEP> Jan. <SEP> Feb. <SEP> March <SEP> Apr. <SEP> May
 <Tb>
 <Tb>
 <Tb>
 <Tb>
 <Tb>
 <tb> proc. <SEP> A <SEP> 943 <SEP> 1.053 <SEP> 1,972 <SEP> 1.353 <SEP> 1.530 <SEP> 1.219 <SEP> 838 <SEP> 396
 <Tb>
 <Tb>
 <Tb>
 <Tb>
 <Tb>
 <Tb>
 <tb> total <SEP> = <SEP> 230.64 <SEP> # <SEP> (9. <SEP> 304 <SEP> Fb).
 <Tb>
 <Tb>
 <Tb>
 <Tb>
 <Tb>
 <tb> proc. <SEP> B <SEP> 943 <SEP> 1.053 <SEP> 3.492 <SEP> 2. <SEP> 427 <SEP> 1,843 <SEP> 1.219 <SEP> 838 <SEP> 396
 <Tb>
 <Tb>
 <Tb>
 <Tb>
 <Tb>
 <Tb>
 <tb> total <SEP> = <SEP> 302.70 <SEP> # <SEP> (12.211 <SEP> Fb).
 <Tb>
 <Tb>
 <Tb>
 <Tb>
 <Tb>
 <tb> proc. <SEP> C <SEP> 943 <SEP> 1.053 <SEP> 4.168 <SEP> 2. <SEP> 909 <SEP> 1.984 <SEP> 1.219 <SEP> 838 <SEP> 396
 <Tb>
 <Tb>
 <Tb>
 <Tb>
 <Tb>
 <Tb>
 <tb> total <SEP> = <SEP> 355.62 <SEP> # <SEP> (13.539 <SEP> Fb).
 <Tb>
 <Tb>
 <Tb>
 <Tb>
 <Tb>
 <Tb>



  Yes <SEP> fuel <SEP> 3. <SEP> 000 <SEP> 5. <SEP> 262 <SEP> 6. <SEP> 058 <SEP> 6. <SEP> 655 <SEP> 5. <SEP> 175 <SEP> 4.702 <SEP> 3.831 <SEP> 1.692
 <Tb>
 <Tb>
 <Tb>
 <Tb>
 <Tb>
 <Tb>
 <tb> total <SEP> = <SEP> 901.71 <SEP> # <SEP> (36. <SEP> 375 <SEP> Fb).
 <Tb>
 <Tb>
 <Tb>
 <Tb>
 <Tb>
 <Tb>



  In <SEP> using <SEP> on <SEP> process <SEP> A, <SEP> on <SEP> GAIN <SEP> completed <SEP> on <SEP> the year <SEP> is <SEP> from <SEP> 671.07 <SEP> # <SEP> (27.071 <SEP> Fb).
 <Tb>
 



  Year 90-91.



   One of the coldest years, characterized by a significant frost in December, January and February Using the A method the annual cost is 214.50 ± (8. 653 Fb). fuel 880.32 # (35,512 Fb). hence a GAIN of 665.82 # (26.859 Fb).
 EMI19.2
 
 <Tb>



  Sure <SEP> the year, <SEP> them <SEP>% <SEP> brought <SEP> by <SEP> on <SEP> sun. <SEP> the air <SEP> and <SEP> the <SEP> geothermal energy:
 <tb> month <SEP> Oct. <SEP> Nov. <SEP> Dec. <SEP> Jan. <SEP> Feb. <SEP> March <SEP> Apr. <SEP> May
 <tb> sun <SEP> 44 <SEP> 55 <SEP> 10 <SEP> 52 <SEP> 33 <SEP> 56 <SEP> 47 <SEP> 37
 <tb> air <SEP> 1 <SEP> 56 <SEP> 45 <SEP> 52 <SEP> 39 <SEP> 16 <SEP> 44 <SEP> 53 <SEP> 63
 <tb> RAF <SEP> 1 <SEP> 0 <SEP> 0 <SEP> 38 <SEP> 9 <SEP> 51 <SEP> 0 <SEP> 0 <SEP> 0
 <Tb>
 
This last presentation allows us to better understand how it works.



  D - Starting the process We finally arrive at the diagram (Fig. 15) Operation 1 -The day from 7 am to 10 pm.



   At 7 am, following an impulse from the PC clock, the "day" program begins. The temperature tha (29) on the ceiling is <25, the PCI pump (28) of the AC transfer circuit (27) is stopped, as is the heat pump (30). It is the hot water of the heating circuit whose temperature oscillates between 25 and 50 which feeds the convectors, the joists or the slabs, PC3 (34) step (M), the solenoid valves vl (37), V3 (38) , V4 (39), V5 (40) are closed, V2 (41) is open.



   When the sun is shining, the temperature tha (29) exceeds 25, the transfer circuit comes into action, PC1 works (M) and stores the heat at the top of the accumulator (AC). PCI throughput is low: 5 to 10 hours maximum. All valves remain in the same position.



   When the sun disappears, tha becomes <25 and PCI returns to a standstill.



  2 - At night from 10 p.m. to 7 a.m.



   At 10 p.m. the night program starts, also on a pulse from the uPC clock.



   As long as thb (42) (the temperature at the top of the accumulator) exceeds 0, the valve VIreste open, V5 opens, PC2 (33), PC3 (34) and the heat pump work. The calories contained in Ac pass into the heating circuit, and when thb (42) becomes <0, PC2 and the heat pump return to standstill, VIet V5 close.



   The thermometer thc (43) of the heating circuit oscillates between 25 and 50.



  If there has been no sun thb remains less than 0, the heat is removed from the air provided that thd (44) is> 5, V2 closes, V3 opens the exchanger serves as evaporator at the heat pump: PC3, heat pump and exchanger are working.



   If there is no sun and the air temperature is insufficient, thd <5, only the circulation pump is running and heat is extracted from the stock. The heating circuit lives with its reserve and when thc falls below 25, the heat is extracted from the ground. V2 and V4 open, V3 closes, PC2 and the PAC work
When the (45) arrives at around 0, heat is extracted from the air during the day provided that thd is> 5, V2 closes, V3 opens, the heat pump and the air exchanger operate.



   Finally when thc <25, thd <5, the <0 and no sun, it is the electric heating (47) which comes into action.



   After May 15, when thc reaches 50, the whole system stops except the circulation pump of the heating circuit which will finally stop on May 31 in order to exhaust the calories of the circuit.



   OPERATION.



  The day
 EMI19.3
 
 <tb> thermometers <SEP> breaks <SEP> circulation <SEP> Solenoid valves
 <tb> contactors
 <Tb>
 <tb> a <SEP> b <SEP> c <SEP> d <SEP> e <SEP> PCI <SEP> PC2 <SEP> PC3 <SEP> PAC <SEP> Vl <SEP> V2 <SEP> V3 <SEP> V4 <SEP> V5 <SEP> Ech.
 <Tb>
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  7 <SEP> h. <SEP> on <SEP> morning
 <Tb>
 <Tb>
 <tb> no <SEP> from <SEP> sun <September> <25 <SEP>> 25 <SEP> A <SEP> A <SEP> M <SEP> A <SEP> F <SEP> 0 <SEP> F <SEP> F <SEP> F <SEP> A
 <tb> sun <SEP>> 25 <SEP> M <SEP> A <SEP> M <SEP> A <SEP> F <SEP> 0 <SEP> F <SEP> F <SEP> F <SEP> A
 <Tb>
 <Tb>
 <tb> exchanger <SEP> and <SEP> PAC <SEP> on <SEP> day <September> <25 <SEP>> 5 <September> <0 <SEP> A <SEP> A <SEP> M <SEP> M <SEP> F <SEP> F <SEP> 0 <SEP> F <SEP> F <SEP> M
 <Tb>
 

  <Desc / Clms Page number 20>

 The night
 EMI20.1
 
 <tb> thermometers <SEP> Pumps <SEP> circulation <SEP> Solenoid valves
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 <tb> contactors
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 <tb> a <SEP> b <SEP> ç <SEP> d <SEP> e <SEP> PCI <SEP> PC2 <SEP> PC3 <SEP> PAC <SEP> Vl <SEP> V2 <SEP> V3 <SEP> V4 <SEP> V5 <SEP> Ech.
 <Tb>
 <Tb>
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 <tb> heat <SEP> removed <SEP> from <SEP> AC <SEP>> 0 <SEP>> 25 <SEP> A <SEP> M <SEP> M <SEP> M <SEP> O <September>

  O <SEP> F <SEP> F <SEP> O <SEP> A
 <Tb>
 <Tb>
 <Tb>
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 <tb> AC <SEP> sold out <September> <0 <SEP>> 25 <SEP> A <SEP> A <SEP> M <SEP> A <SEP> F <SEP> 0 <SEP> F <SEP> F <SEP> F <SEP> A
 <Tb>
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 <tb> heat <SEP> extracted <SEP> from <SEP> the air <September> <0 <SEP>> 25 <SEP>> 5 <SEP> A <SEP> A <SEP> M <SEP> M <SEP> F <SEP> F <SEP> O <SEP> F <SEP> F <SEP> M
 <Tb>
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 <tb> nor <SEP> sun <SEP> and <SEP> tO <SEP> ext.

    <September> <5 <September> <0 <SEP>> 25 <September> <5 <SEP> A <SEP> A <SEP> M <SEP> A <SEP> F <SEP> O <SEP> F <SEP> F <SEP> F <SEP> A
 <Tb>
 <Tb>
 <Tb>
 <tb> extraction <SEP> from <SEP> soil <September> <0 <September> <25 <September> <5 <SEP>> 0 <SEP> A <SEP> M <SEP> M <SEP> M <SEP> F <SEP> 0 <SEP> F <SEP> 0 <SEP> F <SEP> A
 <Tb>
 <Tb>
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 <tb> heating <SEP> electric <September> <0 <September> <25 <September> <5 <September> <0 <SEP> A <SEP> A <SEP> M <SEP> A <SEP> F <SEP> 0 <SEP> F <SEP> F <SEP> F <SEP> A
 <Tb>
 <Tb>
 <Tb>
 <tb> after <SEP> on <SEP> 15 <SEP> May <SEP> 50 <SEP> A <SEP> A <SEP> M <SEP> A <SEP> F <SEP> 0 <SEP> F <SEP> F <SEP> F <SEP> A
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 Possible improvements.



  1 For this pilot house, the calculations were made with an area of bay windows exposed to the South of 32.5 m2.



   As in the process described, recourse is made as a last resort to the heat removed from the air during the day and to the very expensive electric heating, we see that it is advantageous to force the quantity of heat received from the sun, especially when geothermal energy is not, or only slightly, possible.



   The pilot house has a south-facing roof slope with a surface area of 6 * 24 m = 144 m2. If one installs flat solar panels on 1/4 of this surface only, ie 36 m2 for dimensions of 4 * 9m, the solar energy collected becomes double.



  2 The same is true of the energy withdrawn from the air by increasing the capacity of the exchanger.



  3 By adding solar panels on the roof or on the walls (more effective in winter on the walls, because the solar rays fall almost perpendicularly on the panels).



   Concentrated solar panels delivering a much higher temperature and can be stored directly in the heating circuit, without having to go through the heat pump.



   Possibility of replacing the external walls with convectors with insulation and external wall (bricks, various panels), thus capable of storing in the pilot dwelling up to 1,500,000 k Calories, which makes it possible to reduce the thickness of the tanks of the convectors or increase storage capacity in some regions.



  4 In our region, for the weather conditions encountered during these 15 years, the stock of 750,000 kcal. seems sufficient, but it can be reduced in warmer regions by using a lesser thickness for the convector tanks, or the reverse for colder regions. Given the possibility of replacing the exterior walls with insulated convectors, the thickness of the convector tanks may be reduced.



   In some cases, the so-called convector will be reduced to the simple function of calorie reservoir, convection being suppressed (no orifices in the walls).



  5 In this talk, for ease of calculation, we have used fixed temperatures but for better performance and better comfort these temperatures will be modulated by the PC depending on the time and the outside temperatures over a certain period.



   From Norway to Spain and the rest of the planet, this will be the eternal compromise between the amortization of the installation, the yield and the surface of solar collection, the possibilities of air and soil, sometimes l energy to be extracted in addition to water, wind energy or deep geothermal energy.



  2) EQUIPMENT A - Collection of solar energy in homes.



   To simplify the previous calculations, we have chosen joists, but other types of exchangers can be used: hollow slabs, flat exchangers, etc. (Fig. 7) Joists
We took joists of rectangular section, but other forms are possible: for example a trapezoidal or polygonal section will allow to have a larger exchange surface (6-7-8-9-10-11). The dimensions will be calculated according to the load to be supported.



   The inputs and outputs can be located on the same side, the brine being conveyed inside by an internal perforated tube so that the temperature at the joist surface is the same over the entire length, in order to avoid cold areas and do not reach the dew point. In this way the space with the pipes carries on the same side of the room. In some cases, to increase the lift, the inner tube can be welded to the bottom of the joist (tensile strength) (8), with a condensation collector (9).



   The assembly will be mounted in parallel or series-parallel given the very low flow required (500 liters / hour = 5 m3 in 10 hours). They will be connected to each other and to the distribution circuits by flexible plastic tubes of small diameters. Tubes fitted with industrially manufactured quick couplings with standardized dimensions will be used.



   Note that between the joists placed in the sunny rooms, there is a space and it is possible to place flat heat exchangers supplied by the heating circuit. This avoids the use of joists for both solar heat recovery and radiant heating from the ceiling
In new homes when all the interior walls are replaced by convectors, they occupy the entire height. The joists will be installed and attached to these convectors, even if it means reinforcing the latter to support floors. Expansion and soundproofing will be taken into account when installing them.

  <Desc / Clms Page number 21>

 



  Concrete slabs.



   As the joists are visible, some will prefer to see a flat ceiling. We will also use a hollow tube on which we will fix two fins, or a U welded on a sheet (12-13-14). Various shapes will be adopted according to the customer's taste in order to have a sufficient exchange surface, the slabs will be connected to each other by rubber seals for expansion and soundproofing. They will be adapted and fixed like joists, or in combination with joists (15-16).



  1 - Flat heat exchangers.



   Various types of finned trade can be used. The size is much less. It will also be possible to place such exchangers between the ceiling and a sub-ceiling, or a light panel in perforated and decorative plastic hiding the exchangers. This will for example be the case in building restoration. Air circulation can be forced by a fan to increase the exchange power and distribute through openings the cooled air, as is done in cold rooms. Many combinations are possible with these various elements.



  2 - Accumulator.



   The heat is stored in a 5 m 'thermally insulated tank. We can use a thermally insulated tank buried in the ground, plastic molded tanks, polyester reinforced with glass fibers, flexible tarpaulins like those used in the industry for the storage of liquids, etc ...



   This tank or the tarpaulin can be placed in a cellar, a crawl space, a room at the same time as the air-water exchanger and the heat pump.



   A garden shed may be perfectly suitable. Thus, for a height of 2 m, the floor area will be only 2.5 m2 (2m * 1.25m) and the air-water exchanger will be installed there advantageously (supply and discharge air lines more short and no noise in the building). The entire transfer circuit will be protected by anti-rust and anti-freeze as already explained.



  3 - Convectors.



   The convector tanks will be made of metal, preferably iron, given its price and conductivity, but may also be made of stainless steel or other materials.



   In a new home, offices, workshops, etc., the convector tanks are fixed between them with expansion and soundproofing devices (for example silent-block type). They will be placed on an acoustic insulator.



  The tank itself is a good acoustic insulator due to its mass.



   We know that a wall weighing 100 kg / m2 has an insulation index of 40 dB at the average noise frequency of 500 Hz, and that each time we double the mass, the insulation increases by 4 dB. As the tank has a mass of 200 kg / m2 (water only), the sound insulation index at 500 Hz will therefore be 44 dB, practically the same value as that of a 12 cm wall (bricks + plaster) and the convector, with its walls, comparable to a wall of cellular concrete 30 cm thick.



   Under the tanks, rigid PVC tubes, of fairly large diameters, embedded in the concrete and through which pass the flexible pipes connecting the tanks to the distribution pipes.



   Each tank will be trapped between two more or less insulating walls to form the convector (K of the wall between 0.4 and 0.6). (Fig. 16) wood (48). polymer foam (49), air passage (50).



   Openings in the top and bottom of the partitions will allow convection and the furniture chosen with feet (they are most often) will not hinder the circulation of air. These openings will be fitted with fairly solid fabrics (mosquito net type) and removable for cleaning.



   A shutter in the top opening will be controlled by a thermostat housed in the room. The opening at the bottom will be located at the level of the tiling in order to quickly evacuate the water in the event of a fire, if this system is adopted. Water can flow through large rigid PVC pipes provided they are connected to the sewer.



  Heat capacity of convectors.



   In the tanks of these convectors, the temperature varies between 25 and 50.



  The total exchange area for the pilot dwelling is 262 m2 For a height of 2.50 m, the exchange coefficient is 9, given the chimney effect caused by the height. With an air temperature variation of 22 on the ceiling to 18 on the floor and a drop of 25 to 20 in the tank, the average exchange temperature is:
25 22 d2 = 3 # #
20 18 dl = 2 dl / d2 = 0.66 and after correction = 0.81 and Ùm = 2.4
The exchange capacity = 9 * 262 * 24 * 2.4 = 135,820 kCal. corresponding to a temperature difference of 135.820 / 5.805 = 23.5 (able to overcome an outside temperature of -3.5). For a more pronounced frost, the temperature of the tanks will be increased by a few degrees. It is the PC which will regulate this temperature based on the outside temperature.



  Note that it is necessary to add the heat passing through the wall and which is far from negligible.



   We should therefore not look for a way to increase the exchange surface by the processes used for central heating radiators (fins and juxtaposed elements).



   A convector being located between two rooms of the house, it will be possible to use it for the heating of these two rooms, or only one by using a partition without openings on the side which the convector should not heat.



   Note the economy in bricks and labor which compensates for the price of convectors. To have the same sound insulation as the convectors, it would be necessary to use aerated concrete blocks of 50 * 25 and 30 cm thick, and for the 150 m2 of walls: 1,200 blocks and at 3.72 E (150 Fb) the block = 4.462 E (180,000 Fb). + labor, which largely compensates for the price of prefabricated convectors.

  <Desc / Clms Page number 22>

 



   In this installation nothing will be apparent. The installation of flexible pipes will be ultra-fast. (no elbows, no straight lines to respect).



   We have seen that heat storage takes place between 10 p.m. and 7 a.m., and in certain regions or countries, we can take advantage of the off-peak hours allocated by the electricity companies.



   The complete volume of the circuit will have to be renewed, for good, once in a night for a better performance of the heat pump, but the flow rate will depend above all on the exchange power of the condenser of the latter which determines the circulation speed. However, to maintain a low flow rate in the heating circuit, it is possible to use a two-pass circuit with accelerator according to the conventional process used in industry.



   We have placed the tanks in the interior walls, but they can be placed in or on an exterior wall for large buildings where the interior walls are absent. The tanks can cover the entire length and height, we are not limited to the distance from the partition to the wall. It will therefore not be necessary to reduce the thickness of the wall. Advantageously, however, it is possible to use insulated metal panels such as are found more and more in industrial buildings, to reduce the thickness of the wall, the convector tank being "glued" to the insulation.



   Acting as a convector, it is also possible to use the slabs as a heating floor, heat exchangers in the basement, etc.



  B - Heat pumps.



   More than 50 years ago Brown-Bovery already heated its construction workshops with hot water radiators raised to 50, using the heat borrowed from the Limmat river whose water is at a temperature below 10. At the time, the Brown-Bovery review gave the following assessment: - heat removed from the water pumped to the river at a temperature of 5: 1400,000 kCal - electrical energy supplied to the heat pump (expressed in kCal) 500. 000 kCal - heat delivered to heating radiators at 50: 1900,000 kCal For 10,000 kCal withdrawn from the river, the electricity expenditure is (5 * 10) / (14 * 860) = 4.153 kW.



   With the heat pump, the compression work is found in the form of heat and for the 10,000 kCal at the inlet we find 10,000 * 19/14 = 13,570 kCal at the outlet.



   However, the efficiency of a heat pump is linked to the volume refrigerating power; this varies according to the temperature difference before and after expansion. The difference in enthalpy between these two temperatures must be subtracted from the heat of vaporization, which is itself equal to the product of the difference in temperature and the specific heat.



   Using freon 12 (difluoro-dichloromethane) whose specific heat is 0.230 and since the temperature in the accumulator varies between 3 and 25, the pump yields in our pilot house will vary: a / between 25 and 50 at the start, a difference of 25 - the loss of calorific effect is 25 * 0.230 = 5.75 - the latent heat of vaporization at 25 is 33.8 - the actual calorific effect is equal to 33;

  8 - 5.75 = 28.05
As the specific volume at 25 is 0.025, the volume yield is 28.05 / 0.025 = 1122 b / between 3 and 50 (at the end of the night cycle) - loss of calorific effect = 47 * 0.230 = 10.8 - the latent heat of vaporization at 3 is 36.7 - the actual calorific effect = 36.7 -10.81 = 25.89
As the specific volume at 3 is 0.050, the volume yield is 25.89 / 0.050 = 518
In reality, the temperature difference will be higher to allow trade, but the ratio remains essentially the same and the consumption in relation to this ratio.



   This is the reason why the PC will keep the temperature difference as low as possible by the lowest and just sufficient temperature in the heating circuit. And the highest possible minimum temperature in the transfer circuit.



   In the diagram provided by Brown-Boveri (Fig. 17), the freon used is C F C13. Note that the temperature difference is high (42) and therefore the power of the heat pump engine is 4.15 kWh to capture 10,000 kCal, while in our calculations, we have taken an average consumption of 3.85 kWh for very variable but much smaller differences.



  Air - Water heat pump.



   In practice an accumulator is necessary to store the heat. In our case, the accumulator which is none other than the heating circuit does not pose a problem with its 30 m. For the exchanger, the drawback is the significant drop in its performance by the appearance of icing on its fins when the outside temperature is close to 0.



  Water - Water heat pump.



   It can be used advantageously in the process when water is available: a stream, a lake, a pond. Which is quite rare, however. The problems: algae, filtration and fouling of the cap coil. The pump generally draws 3 water, this must be taken into account to avoid any risk of freezing. For the good, the water temperature should be above 5.



   Practice shows that 2 to 3 m3 / h are necessary to heat a medium-sized detached house.



   With groundwater, water is available most of the year at a temperature between 8 and 10.

  <Desc / Clms Page number 23>

 



    Ground - water heat pump. (surface geothermal)
The pump takes heat from the ground through a vertical or horizontal underground hydraulic circuit.



   The vertical circuit requires several very deep boreholes (from 50 to 200m) and is very costly to install. (Beyond 200m, we speak of deep geothermal energy)
Horizontal capture is much preferred. The area covered by the sensors can be up to 3 times the heated area using the system which consists in using the air-water exchanger during the day to reintroduce calories into the ground, the capture area can be considerably reduced.



   In our region (Hainaut), the combination: sun + outdoor air + geothermal energy seems to us the most favorable; but everything will depend on the Country and the environment. Thus in the South of France, Spain, Italy, etc ..., the combination: sun + outside air should most often be sufficient.



   In this study, it is above all the principle that we wanted to demonstrate for a "pilot home in our region" but it is certain that the Building Construction Companies will find something to adapt this process to the various types of homes, industrial premises , offices, etc ... "
So far, we have addressed new construction. In renovation, it will be possible to introduce this heating process while respecting the essential points and the means exposed, but very often, for lack of space, geothermal energy will not be applicable.



  C - Derivative equipment.



  Cooling in summer.



  Although this is beyond the scope of this study, it is possible to use the same equipment to cool the habitat in the summer.



  Sanitary water.



  The same installation can be used all year round for the production of sanitary water using a second coil in the condenser of the heat pump. 3) Other energies.



   Before 1986, the date of the first graphical statement of atmospheric conditions, the situation was as follows and in our opinion has changed little since.



  Wind power.



   In this study, we discarded wind energy, which is very interesting in winter (more wind), because wind turbines must be installed at a fairly long distance from homes (in question: broken blades and noise).



   Domestic wind turbines have a power of 8 to 10 kW for a wind of 10 m / s. They are however advantageously used for detached houses in regions not supplied with electricity and where there is no shortage of space.



   In the process that we describe, it would be very interesting to use such a wind turbine of power, even half as much and directly convert the electricity into heat which would be stored like the other sources (abandon of bulky and expensive electric batteries), but it should solve the problem of blades and noise.



   Until now, powerful wind turbines have been used with blades whose circumference has a diameter of 60 to 90 m. A calculation carried out by the EdF has shown that installed along the Brittany coast, it would take 2,800 to have the same power as that of the Plogoff nuclear power plant.



  Hot water geothermal energy.



   One exploits deposits of hot water around 70 for the heating of the houses (rare).



  Deep geothermal energy.



   Heat removed at great depth. In this process, we speak of injecting water on the granite rocks that are found everywhere at a depth of 3,000 to 6,000 m to produce large amounts of vapor.



   Would be profitable for heating a few thousand dwellings, and interesting in built-up areas, associated with the recovery of solar heat and air with the process. This would allow deep geothermal heating to be spread to more homes. Great interest also in very cold regions .... ?? Tidal.



    In France, the Rance power station managed to produce current at an attractive price: 0.022 # (0.92 Fb) per kW, nuclear energy returned to around 0.019 E (0.77 Fb) per kW. Unfortunately the sites are rare or involve considerable costs.



    Wave energy: By articulated raft trains: specific to the English?
Thermal energy of the seas: Temperature difference between the surface and the bottom up to 20. It was found to be unprofitable.



  Other techniques for solar energy.



   - Photovoltaic energy: its operation is too expensive; - Centrale Themis (France): mirror sensors. Large installation to produce electricity which would return around 0.30 E (12.28 Fb) per kW This was the situation around 1984.

  <Desc / Clms Page number 24>

 



   Faced with the difficulty of finding an energy that does not produce C02, the process described makes its contribution 4) Fallout from this process.



  1 - Effect on health.



   By adopting this process, some people will fear for health.



   - "long-term effect: during its evolution, for hundreds of thousands of years, man has never been subjected to such bombardment of waves of all frequencies" - Effectively with such wave sensors, we have to worry about it even more;

   if we connect this set of iron to the earth, we find ourselves in the case of Faraday's cage and largely sheltered from these waves which cross us from head to toe to flow into the ground. " Low frequency waves radiated by the electrical installations of the houses, the high voltage cables, and the high frequency waves of radio, television, GSM "
To protect yourself even better and prevent waves from passing through exterior walls, you should place a light metal screen, also connected to the floor between the wall and the ceiling. There will remain waves entering through windows, but as they pass through walls and walls, they will be largely absorbed before reaching the human body, unless inventing a glass conductive of these waves.



  2 - Earthquakes.



   We can see the advantage of this type of construction. (no bricks, no concrete) 3 - Fire fighting
In homes, offices, factories:
From the walls which will resist for a very long time releasing large quantities of suffocating vapor and preventing any propagation.



   By installing the system, very reliable, described above hidden in decorative elements serving as diffusers installed under joists or slabs to reduce to zero any fire.



  4 - Industry.



   Steel - Rolling mills.



   Prefabrication of tanks.



   The prefabrication of the walls and all the ancillary equipment.


    

Claims (6)

CLAIMS. Process for heating a home with renewable energies, characterized by: 1 - The surplus of solar calories entering through the windows is captured on the ceiling by a cold brine circulating in metal pipes which replace the joists and / or the slabs usually used. This heat is temporarily stored in an accumulator to be transferred overnight by a heat pump in the heating circuit. 2 - The heating circuit consists of convectors used for both storage and heating. 3 - The convectors replace all the interior walls so that their tanks, of rectangular shape and occupying the entire surface of the interior walls, can store the necessary and sufficient amount of water. These tanks are enclosed between two insulating walls spaced a few cm apart with openings at the top and at the bottom to allow convection. The openings at the top are equipped with thermostatic shutters to regulate the temperature of the house. Dependent conclusions : 4 - Use of a heat pump with 2 evaporators for the simultaneous capture of solar and au heat in order to quickly replenish the calorie stock 5 - For the heat pump, obtaining a high COP from the large heating surface of the convector tanks which still allows heating with a temperature close to 25. 6 - Given the low temperature at the outlet of the heat pump, the possibility of using solar panels capable of supplying calories at low temperature and thus capture a larger part of the diffuse solar energy.