HRP20150840A2 - Heat reservoir with two parts of different temperatures to use with low-temperature polymer solar collectors with high heat capacity - Google Patents

Abstract

SUMMARY OF THE INVENTION The use of low temperature solar collectors (30) in two modes of operation using a heat reservoir (20) having two parts with different operating temperatures (29A and 29B) interconnected (overflow) (instead of one part of the tank may be a heat exchanger (26 )). A container (20) with two thermally insulated chambers (29A, 29B) allows low-temperature solar collectors (30) to operate in two different modes of operation. In the first operating mode, when the solar collectors (30) are connected to the chamber 1 (29B) of the tank (20), the water is heated by external heat and solar radiation to about 45 ° C (on a warm sunny day) with minimal pump power consumption. In the second operating mode, when the solar collectors (30) connected to the heat pump (10), the water in the chamber 2 (29A) is heated to the desired temperature of 65 ° C or more regardless of the outside temperature and sunshine.

Description

The field to which the invention relates

This invention relates to a hybrid heat pump system combined with low-temperature polymer solar collectors, and according to the international classification classified as F25B 25/00, F25B 27/002 and F25B 30/00.

Technical problem

If the solar polymer collectors through which the liquid flows are connected via a heat exchanger to the evaporator of the heat pump, and in such a connected system the heat pump heats the hot water, the total consumption of electricity for the operation of the heat pump and the circulation pump is 5 to 10 times higher (depending on the insolation) from the electricity consumption that a classic solar system with a pump and a polymer solar collector would have.

If we only use a system with a pump and a polymer solar collector, the ratio of invested and obtained energy is 5 to 10 times better, but the temperature of the obtained hot water can reach about 45°C only on a sunny, hot day, which is not enough for use in hotels and is therefore necessary use of the water heating system.

State of the art

There are several solutions of using polymer or composite low-temperature solar collectors in combination with a heat pump, but we are not aware of any multi-functional use of low-temperature solar collectors in such a way that they are used alternately in the first way using a pump to heat water through solar radiation and using ambient heat and in another way, that it is connected via an exchanger to the evaporator of the heat pump that heats the water to a higher temperature.

Presentation of the essence of the invention

The essence of the invention is a container that enables the use of low-temperature polymer or composite collectors in two operating modes by using a thermal container that has two parts connected to each other (overflow) with different operating temperatures. The low-temperature part of the tank allows us to collect energy directly from the environment and solar radiation (with little energy input) with low-temperature polymer collectors. In the high-temperature part of the tank with the heat pump, we prepare water at the temperature that the user needs (55°C, 65°C or more) and then the heat pump evaporator is connected via a heat exchanger to solar low-temperature polymer or composite collectors.

The first advantage of the invention is a significantly lower consumption of electricity than a system with a heat pump that has an evaporator directly connected to low-temperature polymer solar collectors. The main energy saving is achieved by switching between system modes. When there is enough solar energy and external heat, this energy is collected without a heat pump, which is a bigger consumer of electricity for the same delivered thermal energy than a regular water pump.

Another advantage of the invention is the possibility of using polymer solar collectors when there is no sun or at night using low temperature solar collectors as heat exchangers with the environment. Low-temperature polymer solar collectors do not have protective glass and can freely exchange heat with the environment.

A short list of images

The accompanying pictures, which are included in the description and which form part of the description of the invention, illustrate the best way to carry out the invention considered so far, and help to explain the basic principles of the functioning of the invention, whereby: Figure 1 - tank divided into two parts by an insulating partition and connected to the collectors and the crane warmth; Figure 2 - tank physically divided into two parts (two tanks) and connected to the collectors and the heat pump; Figure 3 - tank equipped with heat exchanger, temperature sensor and pump. The pump is turned on only when there is an inflow of cold water into the tank and there is accumulated thermal energy in the polymer collectors of high thermal capacity. Then the accumulated thermal energy is taken from the polymer solar collectors with high thermal capacity. This design avoids the need for an additional tank with the possibility of using polymer low-temperature collectors in two modes of operation.

Figure 4 - use of the system explained in Figure 2 but for space heating

Detailed description of four ways of realizing the invention

The first way

The system is used to heat (Figure 1) domestic hot water (DHW) in such a way that the desired temperature of 45-65T (or more) is maintained in chamber 2 (29A) of the tank as measured by the temperature sensor (21A). In chamber 1 (29B) of the tank, a temperature that can be achieved by low-temperature polymer solar collectors (30) is maintained up to about 45°C. Instead of cold 10-15°C water from the water supply coming into chamber 2 (29A), low-temperature polymer solar collectors (30) are used, which in chamber 1 (29B) preheat the water from the water supply using a heat exchanger (19) (a version without exchanger (19) in such a way that the same liquid flows inside the tank and solar modules (30)), the preheated water passes into chamber 2, and only then, if there is a need in chamber 2 (29A), the water is additionally heated to 45-65°C (or more) using a heat pump (10) that will use low-temperature polymer solar collectors (30) in such a way that they will be connected via a heat exchanger to the evaporator, and chamber 2 (29A) is connected to the condenser of the heat pump (10) directly or via a heat exchanger. Depending on the weather conditions (insolation and temperature) read by the sensor (31) on the solar collector (30) and the temperatures in the tank chambers read by the sensors (21,22), the control unit (40) controls the three-way valves (51,53) and the pump (52) ) and the heat pump (10) and thus selects the system operation mode.

Another way

The same working principle as the 'First method', except that chamber 1 and chamber 2 are physically separated (picture 2). This means that chamber 1 (29B) becomes tank (27) and chamber 2 (29A) becomes tank (28).

The third way

The system serves to heat (Figure 3) PTVa in such a way that the desired temperature of 45-65°C (or more) is maintained in the tank (28). The tank is connected to a heat exchanger (26) (which replaces chamber 1) and a temperature sensor (21A). Instead of cold water coming into the tank (28) from the water supply at 10-15°C, low-temperature polymer solar collectors (30) are used, which preheat the water to 15°C-45°C° via the heat exchanger (26). The pump (52) is turned on only when there is an inflow of cold water into the tank (28) and there is accumulated thermal energy in the polymer collectors of high thermal capacity (30). Then, the accumulated thermal energy (30) is taken from the polymer solar collectors with a high thermal capacity and transferred to the cold water entering the tank. This design avoids the need for an additional tank with the possibility of using polymer low-temperature collectors in two modes of operation.

The water is additionally heated to 45-65°C (or more) using a heat pump (10) that will use low-temperature polymer solar collectors (30) in such a way that they will be connected via a heat exchanger to the evaporator, and the tank (28) will be connected with the heat pump condenser (10) directly or via the heat exchanger. Depending on the weather conditions (insolation and temperature) read by the sensor (31) on the solar collector (30) and the temperatures in the tank chambers read by the sensors (21,22), the control unit (40) controls the three-way valves (51,53), the pump ( 52) and the heat pump (10) and thus selects the system operation mode.

The fourth way

The system serves to heat (Figure 4) the hot water for heating in such a way that the desired temperature of 45-65°C (or more) is maintained in the tank (28) as measured by the temperature sensor (21A). The tank (27B) maintains a temperature that can be reached by low-temperature polymer solar collectors (30) of 15°C-45°C. The tank (27B) can be connected to the rest of the system via a heat exchanger (19) or directly in such a way that the tank is filled with a mixture of water and glycol and the same liquid flows through the tank (27B) through pumps (52,54) and three-way valves (51,53). .

The water is heated to 45-65°C (or more) using the heat pump (10) in such a way that the low-temperature polymer solar collectors (30) or tank 27B will be connected to the evaporator via the heat exchanger, and the tank (28) will be connected to the condenser. heat pumps (10) directly or via a heat exchanger. Depending on the weather conditions (insolation and temperature) read by the sensor (31) on the solar collector (30) and the temperatures in the tank chambers read by the sensors (21,22), the control unit (40) controls the three-way valves (51,53) and the pumps (52) ,54) and the heat pump (10) and thus selects the system operation mode.

Description of call signs

10 Heat pump/ heat pump with heat exchanger

19 Heat exchanger inside the lower temperature tank (part of the tank).

20 Hot water tank with two chambers that includes (19,21,22, 23,25,29A, 29B)

21 Temperature sensor for the higher temperature tank chamber (chamber 2)

21A Temperature sensor for the higher temperature tank

22 Heat exchanger inside the higher temperature tank

23 Temperature sensor for lower temperature tank chamber (chamber 1)

23A Temperature sensor for the lower temperature tank

24A Lower temperature tank

25 Thermal insulation between chamber 1 and chamber 2 with openings for water passage

26 Heat exchanger outside the tank

27 Lower temperature hot water tank

28 High temperature hot water tank 29B chamber 1

29A chamber 2 (higher temperature water)

30 Thermodynamic polymer solar collectors of high thermal capacity (they do not have glass and freely exchange heat with the environment)

31 Temperature sensor and sunlight sensor

40 Central computer for regulating the operation of three-way valves and pumps

51 Electronically controllable three-way valve

52 Pump for a mixture of glycol and water

53 Electronically controllable three-way valve

54 Pump for a mixture of glycol and water PTV - domestic hot water

Claims (2)

1. A heat tank with two different temperature parts consists of a heat pump (10), low-temperature solar collectors (30), a tank (20) with two chambers of different temperatures (29A, 29B) and two heat exchangers (19, 22), temperature sensors (21, 23, 31), control unit (40) that controls the operation of the heat pump (10), water pump (52) and three-way valves (51,53), characterized in that the tank (20) with two thermally insulated interconnected chambers (29A, 29B) enables the low-temperature solar collectors (30) to work in two operating modes, in the first operating mode, when the solar collectors (30) are connected to chamber 1 (29B) of the tank (20), the water is heated via the exchanger (19) by external heat and solar radiation up to about 45°C with minimal consumption of electric energy of the pump (52), and if the desired temperature is not reached in the first mode, the system can also work in the second mode of operation when the solar collectors (30) are connected to the heat pump (10), the water is in chamber 2 (29A) over heats the exchanger (22) to the desired temperature of 65°C or more, regardless of the outside temperature and sunlight. 2. A heat tank with two different temperature parts consists of a heat pump (10), low-temperature solar collectors (30), a tank (28) with a heat exchanger (22), a heat exchanger (26), temperature sensors (31.21 A) and control units (40) that control the operation of the heat pump (10), the pump (52) and the three-way valves (51, 53), characterized by the fact that the tank (28) with the heat exchanger (26) enables the low-temperature solar collectors (30) to work in two mode of operation, in the first mode of operation when the solar collectors (30) are connected directly to the heat exchanger (26) and the water passing through the heat exchanger (26) is heated by external heat and solar radiation to about 45°C with minimal pump energy consumption (52 ) and if the desired temperature is not reached in the first regime, the system can also work in the second regime when the solar collectors (30) are connected to the heat pump (10), the water in the tank (28) is heated to the desired temperature of 65°C via the exchanger (22) or more regardless of the outside temperature and sun exposure.