FR2505990A1 - Local heating system using solar, geothermal and heat pump sources - has heating water storage and domestic hot water storage heated by coil heat exchangers supplied with heated fluid - Google Patents

Abstract

The local heating system is partic. applicable to groups of domestic dwellings and comprises: a reservoir (1) of hot water for heating usage which is circulated through a heating circuit (2,3) by a circulation pump (5) and a solar energy collector (10) supplying a circuit (8,9) with a heat exchanger (7) in the reservoir (1). A heat pump (16) supplies a circuit (14,15) with a heat exchanger (13) in the reservoir (1). A geothermal energy collector (17) supplies the input circuit (18,19) to the heat pump. Each circuit has a pump and control valves incorporated. The heating circuit (2,4) has a mixing valve (4) to mix some of the return water in the heater inlet when the temp. in the heating circuit exceeds a set value. A source of hot water for domestic hot water is also incorporated (30,31,32) and is driven off the solar, geothermal and heat pump heat sources.

Description

 The invention relates to systems. pov heating: premises, in particular for individual or collective accommodation.

 The invention also applies to heating systems for offices.

 Its aim is to provide a new heating system that uses natural energies as much as possible, either instantaneously or after accumulation, while allowing regular heating and when these energies are insufficient, especially in cold periods.

 The system according to the invention is characterized in that it comprises: a hot water heating tank supplying water to a heating circuit with circulation pump; at least one solar energy sensor supplying a first circuit which includes a first reheating exchanger for the tank; a pump and a valve mounted on this first solar circuit; a heat pump supplying a circuit which includes a second exchanger for heating the tank; a pump mounted on this heat pump output circuit; a geothermal energy sensor supplying an input circuit of the heat pump; a pump and at least two valves on this geothermal circuit; a second solar cooker bypass on the first exchanger and on the inlet of the heat pump; a valve mounted on this branch circuit; a third exchanger in the tank, supplied by an auxiliary energy source; and temperature detection and control means for said pumps and valves, suitable for heating the tank, giving priority successively to solar heating either by the first exchanger, or by the heat pump and the second exchanger, alone or in combination association with the geothermal circuit, with the geothermal circuit by the heat pump and the second exchanger, finally with the auxiliary energy source by the third exchanger and also preferably put in communication the solar and geothermal circuits so as to store in this is unused solar energy.

 The above heating system is advantageously supplemented by a device for supplying domestic hot water which comprises: a domestic hot water tank supplying a circuit for use; a third solar circuit mounted as a bypass on the first solar circuit and comprising a pump and a fourth exchanger for rrcllau ^ -age of the tank; a fifth heat exchanger for heating the tank, mounted on a coia-portart circuit of a pump and bypass on the outlet of the heat pump; a sixth exchanger in the tank 1 supplied by an auxiliary energy source; and means for detecting temperatures and controlling said pumps for heating the water in the tank, giving priority to the third solar circuit, then to the heat pump, then to the auxiliary energy source.

 The invention will be clearly understood on reading the description which follows of a preferred embodiment of the invention, made with reference to the appended drawing which forms part of the description and which shows the general diagram of the system, supplemented by a domestic hot water supply device.

 We will first describe the part of the system according to the invention which, according to its simplest aspect, relates only to heating.

 The system comprises a heating tank 1, of the balloon type, on which are mounted the flow pipe 2 and the return pipe 3. These two pipes are coupled by a three-way valve 4. A pump 5 ensures the circulation of the water for the supply of the heating bodies shown diagrammatically in 6 (radiators, convectors, underfloor heating, etc.). A thermal probe t1 measures the water temperature on flow 2, downstream of the three-way valve 4.

 The water in tank 1 is heated from three possible sources.

 A first heat exchanger 7, in the tank, is connected to pipes 8, 9 leading to at least one solar collector 10. On the pipe 8 are successively mounted, from the sensor 10 of which they constitute the start, a pump Il and a valve 12.

 A thermal probe t2 measures the water temperature at the downstream end of the sensor 10. A thermal probe t3 measures the outside temperature.

 A second heat exchanger 13, in the tank 1, is connected to pipes 14, 15 leading to the hot source, or outlet, of a heat pump 16. On the circuit 14, 15 is mounted a circulation pump 25.

 The heat pump 1o is known to those skilled in the art; it will therefore not be described here in detail; it suffices to indicate that it makes it possible, using an intermediate fluid subjected to evaporation, compression and condensation, to obtain at the outlet a temperature higher than that at the inlet.

 The cold source1 or input of the heat pump 16 is constituted by two branch circuits. A first circuit comprises a buried geothermal energy sensor, shown diagrammatically at 17, which is connected to two pipes 18, 19 on one, 18, of these pipes are fitted in series with a valve 20 and a pump 21. This sensor is also known in itself; it suffices to indicate that it is constituted by a long buried pipe, the water which it contains taking from the ground the thermal energy putting it at the same temperature as the latter. A thermal probe t4 measures the water temperature of the sensor 17, at the downstream end of the latter.

 The second circuit for forming the cold source of the heat pump 16 is of the solar type. Between the pump II and the valve 12 is connected a pipe 22 which carries a valve 23 and which leads to an inlet of the heat pump. Line 24 is connected to line 9 and leads directly to the other inlet of the heat pump. A valve 26 is mounted at the inlet of the heat pump, between the latter and the junction of the pipes 19 and 22.

A third heat exchanger 27, in the tank 1, is intended to provide this one. additional thermal energy when the power supplied by the solar collector 10 and / or the geothermal collector 17 is not permanently sufficient; this is particularly the case in the cold season or, if necessary, in the mid-season, generally at night. This additional energy is provided by. an auxiliary source shown diagrammatically at 28 which may be of the electric or fuel type,
The temperature of the water in the tank 1 is measured by a thermal probe t5.

 The pumps 5, 11, 21 and 25 are activated from a centralized control unit 29.

 Pump 5 runs continuously during the heating period (mid-season and winter). On the other hand, the pumps 11, 21 and 25 only rotate, during the heating period, when the circuits with which they are associated circuit of the solar collector 10, geothermal circuit and output of the heat pump towards the tank) must be used. .

 The unit 29 also controls the valves A, 12, 20, 2) and 26 ensuring various functions: the three-way valve 4 has - for role, under the control of the probe t1 and the set temperature 81 assigned to the heating water at the outlet of the circulation pump 5, to incorporate return water on the flow 2 to maintain t1 (temperature measured by the probe t <) near # 1, for example at most at # 1 "C with respect to 81; the valve 12 has the role of activating the exchanger 7 when the solar circuit 8, 9 is used to directly heat the tank 1; the valve 23 has the role of activating the circuit solar 22, 24 to the heat pump 16 and / or to the geothermal sensor 17, and to allow the storage of solar energy in the ground; the pump 21 has the role of activating the geothermal circuit 18, 19; valve 26 has the role of activating the heat pump for its operation by the solar circuit 22, 24 and / or by the geothermal circuit 18, 19.

 The valves 12, 23 are either closed together or open alternately. The pump 11 only runs if one of the valves 12, 23 is open. The pump 21 only runs if the valve 20 is open. The pump 25 only runs if the valve 26 is open.

 The centralized control unit 29 receives its information from the probes t1 to t5, this information being significant of the temperatures measured.

 The data processing means in the unit 29 and the pump and valve control means will not be described in detail because they are within the reach of those skilled in the art, taking into account the operating data indicated here. -after.

 If heating is not required, pump 5 is turned off and normally pumps 11, 21, 25 and valves 12, 20, 23, and 26 are closed.

During the heating period (mid-season or winter), the pump 5 runs continuously, while the pumps 11, 21, 25, the valves 4, 12, 20, 23, 26 and the source 28 are selectively controlled as a function of instantaneous measured parameters (t1-t5), time (in the case of selective day / night heating) and setpoint parameters (# 1, safety temperature in the tank, etc.)
The set temperature 81 is programmed either as a function of t3 and the time, or independently of t3, as a function of the time, for example only; in the latter case, the t3 probe is not necessary. Initially, the backup source 2> is out of service, the valve 4 is in direct passage, the pumps 1, 21, 25 are stopped and the valves 12, 20, 23, 2 are lennnes.

 If t1 is greater than, for example, 61 +1 C, the valve A opens in the direction of incorporating part of the return water from the pipe 3 into the pipe 2. The valve 4 resumes in direct passage when t1 drops to approximately 61 - 1 C. A temperature close to the set temperature # 1 is thus maintained in the heating bodies 6. This incorporation of part of the return water is only carried out when the valve 12 is open, that is to say during the only solar heating through the exchanger 7, which provides instant energy. and free.

 If t2 is / or becomes less than 61 the solar collector 10 is unable to supply the necessary energy; valve 12 is therefore closed. If t2 is also less than t4, solar energy should not be stored; the valve 23 is also closed, and the pump 11 is stopped. Solar heating is thus switched off in favor of geothermal heating: the valves 20, 26 have opened and the pumps 21, 25 are rotating. If after a predetermined period following the start of the pump 25, and with repetition for equal periods, for example 10 min, t1 is less than for example 81-30C, which means that the geothermal energy is insufficient, the source of booster 28 is activated and the rest until t1 for example reaches 91 + 10C.

The cycle continues, with measurements of t1 spaced over time, to selectively use the auxiliary source to bring it back to a maximum value (# @ + 1 C) 28 when t1 reaches a minimum value (# 1- 3 C), / source cutoff. In variants, the measurement of t1 can be done continuously and / or the activation of the auxiliary source 28 can cause the geothermal heating to be put out of service. If t is however greater than t4, solar energy can be used in conjunction with geothermal energy; the valves 20, 23, 26 are open and the pumps 11, 21, 25 rotate. As in the previous case, the measurement of t1 (continuously or at separate intervals) controls the use of the auxiliary source 28 if the combined power of the solar heating and the geothermal heating is insufficient.

If t2 is greater than or equal to 61 (for example in sunny weather in mid-season or in winter), solar heating is implemented, either directly by the exchanger 7, or indirec teme71t by the heat pump 16. The valve 12 opens and the pump p? turned. In this state, t1 is measured at predetermined trip intervals: if t1 is greater than or equal to for example? 7th 61 + 1cC, there is mixing by the three-way valve 4, this being reset in the direct direction when t1 becomes lower to for example # 1-1 C. When valve 12 is open, t5 is measured z predetermined time intervals: if t5 remains greater than or equal to 81, valve 12 remains open, solar heating by exchanger 7 therefore being sufficient; if t5 becomes less than # 1, valve 12 closes while valves 23 and 26 open and pump 25 turns. There is therefore heating of the tank 1 indirectly by solar energy, through the heat pump. When the pump 25 is running, t5 is measured at predetermined time intervals: if t5 becomes greater than or equal to for example e1 + 1 C, the valves 23, 26 close, the pump 25 stops and the valve 12 opens for a new regulation cycle by measuring t5; if t5 becomes less than 5 than e1, solar heating by the heat pump is insufficient: if t2 is less than t4, geothermal heating is implemented by activating pump 21 and valve 20, the pump with heat being supplied by the solar circuit and the geothermal circuit in parallel; alternatively, the heat pump can be supplied only by the geothermal circuit; if, on the other hand t2 is greater than t4, the geothermal heating will be a fortiori insufficient. Continuation of the measurement of t5, after activation of the pump 25, whether or not followed by that of the pump 21, commands the activation of the auxiliary source 28: if t5 becomes greater than or equal to 61 + 1 C , the source 28 is cut off; if t5 is between e1 + 1 C, the source 28 is kept in service; the source 28 is preferably calculated so as to be able to maintain by itself the temperature t at least # C, 10, whatever the value of # 1. 5
I1 emerges from the above that with the system according to the invention, priority is given successively: solar heating by the heat exchanger 7, solar heating through the heat pump, geothermal heating, with or without heating solar according to the capacity thereof, and finally to the auxiliary heating.

 The system is advantageously supplemented by a device for supplying domestic hot water.

 A domestic hot water tank 30 is supplied with cold water from the network by a pipe. The domestic hot water circuit comprises, on the flow 32, a three-way valve 33, a circulation pump 34, user stations, shown in 35, which are mounted on a 3G loop pipe leading to the return 37. The valve 33 is also connected to the cold water supply 31. The domestic hot water circuit is therefore of the closed type. The water circulates there permanently, by the path 30, 32, 36, 37, under the action of the pump 34 which rotates continuously.

 A thermal probe t6 downstream of the valve 33, measures the temperature of the water available at the stations 35 and acts on the valve 33 to optionally incorporate cold water from the supply 31 into the circuit.

 A thermal probe t7 measures the temperature of the water in the tank 30.

 Like the tank 1, the tank 30 is heated in three ways (solar, heat pump, auxiliary source). A first exchanger is mounted at the ends of pipes 39, 40 which are connected in parallel to the solar collector 10, a circulation pump 41 being mounted on this circuit. A second exchanger 42 is mounted at the ends of pipes 43, 44 connected in parallel to the outlet of the heat pump 16, a circulation pump 45 being mounted on this circuit. A third exchanger 46 is intended to supply additional heat from a source 47 of the same type as the source 28.

 The pump 34 operates continuously, while the valve 33, the pumps 41, 45 and the source 47 are activated from the centralized control unit 29.

 Whatever the other operating conditions, and in particular the outside temperature t3 and the temperature t7 of the tank, the temperature t6 measured controls the valve 33 so that t6 is not higher than a set temperature # 6, generally 55 C. If t6 exceeds # 6, the valve 33 is controlled in the mixing direction, to be brought back in the direct direction when t6 drops to, for example, 66-10C.

 A set point 437 is assigned to t7, for example 60 "C. The comparison of t7 and e7 controls the shutdown of the three thermal sources or, on the contrary, their implementation according to the same priorities as for heating.

 At the start, the pump 34 rotates, the valve 33 is slaved to t; and the pumps 41, 45 are stopped and the source 47 is cut off.

 If t7 becomes or is greater than 07, elements 41, 45, 47 are out of service.

 If t7 becomes less than, for example # 7-1 C, the heating of the tank is necessary: if t2 is greater than or equal to e7, the pump 41 is started, to be stopped if t2 is or becomes less than (37 -1 C; if t2 is less than 87-1 C, solar heating by exchanger 38 is insufficient, pump 41 is stopped, pump 45 is started and valve 26 is open; if t2 is greater than t4, the pump 11 is started and the valve 23 is open: the tank 30 is heated by solar energy through the heat pump 16; if t2 is less than or equal to t4, the pump 11 is stopped, the valve 23 is closed, while the pump 21 is started and the valve 20 is open: the tank 30 is heated by geothermal energy through the heat pump; alternatively, the heat pump can be supplied by the two circuits in parallel. If the heating by the heat pump is insufficient (for example t7 ## 7-2 C), the auxiliary source 47 is switched on. e until t? = 07.

 We therefore see that domestic hot water receives its heat according to the same priorities as heating.

 Many modifications, additions and adaptations are possible without departing from the scope of the invention; This is how we can incorporate any desired security, all time constants in the temperature measurements, any accumulation of solar energy in the geothermal collector when the solar energy (represented by t2) is significant, especially in the non-heating phases of the tank 1 and tank 30, and any priority for the production of domestic hot water over heating.

Claims (6)

 1.- Heating system for premises, in particular for residential locau, characterized by the fact that it comprises: a view (1) of heating water supply supplying water to a heating circuit (2, 3) with pump circulation (5); at least one solar energy sensor (10) supplying a first circuit (8, 9) which comprises a first exchanger (7) for reheating the tank (1); a pump (11) and a valve (12) mounted on this first solar circuit (8, 9); a heat pump (16) supplying a circuit (14, 15) which comprises a second exchanger (15) for reheating the tank (1); a pump (25) mounted on this circuit (14, 15) output from the heat pump (16); a geothermal energy sensor (17) supplying an input circuit (18, 19) of the heat pump (16); a pump (21) and at least two valves (20, 26) on this geothermal circuit (18, 19); a second solar circuit (22, 24) bypassed on the first exchanger (7) and on the input of the heat pump (10); a valve (23) mounted on this branch circuit (22, 24); a third exchanger (27) in the tank, supplied by a source (28) of auxiliary energy and temperature detection means (t1-t5) and control (29) for said pumps and valves, suitable for S heat the tank (1) by giving priority successively to solar heating either by the first exchanger (7) or by the heat pump (16), and the second exchanger (13), alone or in association with the circuit geothermal, to the geothermal circuit by the heat pump (16) and the second exchanger (15), finally the auxiliary energy source (28) by the third exchanger (27).  2.- System according to claim 1, characterized in that the heating circuit (2, 4) comprises a mixing valve (4) for incorporating part of the return water into the heating flow, in the case of solar heating u- @ through the first exchanger (7), when the instantaneous temperature (t1) in the heating circuit exceeds a predetermined salt.  3.- Systene according to one of claims 1 and C, characterized in that a valve (26) is mounted between one of the heat pump inputs and an associated junction of the solar bypass circuits (22, 24) and geothermal (1 @,  @@@ System according to one of claims 1 to 3, characterized in that it is supplemented by a device for supplying domestic hot water which comprises: a hot water tank (30) sanitary supplying a user circuit (31, 32); a third solar circuit (39, 40) mounted as a bypass on the first solar circuit (8, 9) and comprising a pump (41) and a fourth heat exchanger (38) for heating the tank; a fifth heat exchanger (42) for reheating the tank (30), mounted on a circuit (43, 44) comprising a pump (45) and derivative thereon on the outlet of the heat pump (16); a sixth exchanger (46) in the balloon (30), supplied by an auxiliary energy source (47); and temperature sensing (t6, t7) and control (29) means of said pumps for heating the water in the tank (30) giving priority to the third solar circuit (39, @ 0), then to the heat pump (16), then to the auxiliary energy source (47).  5.- System according to claim 4, characterized in that the use circuit (31, 32) is of the looped type and comprises a circulation pump (4).  6.- System according to one of claims 4 and 5, characterized in that the use circuit (31, 32) comprises a mixing valve (33) for incorporating on the starting pipe (32) a part of cold water, under the control of a set temperature and the temperature (t6) of the water available at the user stations (35).  7. System according to one of claims l to 6, characterized by the fact that the temperature detector (tl-t5) and control (29) means are adapted to put the solar and geothermal circuits in communication so as to store unused solar energy in it.