LV13712B - Solar energy collector with heat pump - Google Patents

Abstract

The invention concerns to the individual solar energy collecting devices, which absorb solar energy and use it for heating water envisaged for domestic and production needs. The looked at solar energy collector device, consisting of the solar energy collector, hot water basin-thermos and pipes, connecting in the shape of a loop the canal of the heat carrier of the collector absorber with the heat exchanger located into the basin-thermos. In order to improve the efficiency parameters of the device, the heat accumulating basin-thermos is provided with a heat pump, the evaporator of which into the bottom zone of the basin-thermos is placed beside the heat exchanger, but the condenser is located at the top of the basin-thermos, i.e. it is placed into a hot water zone. In order to favor the split of the hot water in the basin-thermos into lamina after the gradient of the temperature, both zones are separated by perforated diaphragm.

Description

SOLAR ENERGY COLLECTOR WITH HEAT PUMP>

(g) Summary: The invention relates to individual solar energy collectors that absorb solar heat used to heat water for domestic and industrial purposes. A solar collector device consisting of a solar collector, a heat storage tank-thermos and tubes that loops the collector's absorber heat carrier channel to the heat exchanger in the tank is considered. To improve the energy performance of the device, its heat accumulating tank-thermos is equipped with a heat pump located in the lower area of the tank-thermos adjacent to a heat exchanger there, and a condenser located at the top of the tank-thermos, i.e. a hot water drainage area. In order to facilitate the stratification of the water in the tank heat by a temperature gradient, the two zones are separated by a perforated diaphragm.

Solar energy collector with heat pump

Description of the Invention

The present invention relates to individual solar collector devices that absorb solar heat used to heat water for domestic and industrial purposes. Such devices are extensively reviewed [Berlit Davin, Vārme i smāhus, Solvārmesystem for smāhus. Konsumentverket, 1998, 8: e reviderade upplagen (translation from Swedish or., Heating in private homes); (Felix A. Peuser, Karl-Heinz Remmers, Martin Schnauss. Solar Thermal Systems. Solarpraxis. Berlin, 2002, p.364)] and their classical variant is shown in Fig.1.

The device consists of a solar collector 1, a heat storage tank-thermos 7; solar collector loop (loops) - collector absorber 2, venting valve 6, heat exchanger (glodene) 13, one-way flow valve 12, filling valve 4, circulation pump 5 and expansion vessel 3; hot water removal circuit - water mixing valve 14; a hot water consumer 15 and a cold water supply valve 17; automatic control systems - automatic control unit (VB) and temperature sensors TS1 and TS2.

To operate the device, they fill the manifold circuit with a heat-resistant, non-freezing fluid (antifreeze, which is less harmful to the environment, usually propylene glycol). When the solar rays warm up in the collector absorber and the liquid there temperature, which is recorded by TS 1, becomes higher than the temperature recorded in the tank thermos with TS2, the control unit switches on a circulating pump to transfer heat from the collector circuit to the tank thermos. When the temperature in the tank-thermos area where the collector circuit glow is located is higher than the temperature at the top of the absorber, the control unit shuts off the circulation pump, but the one-way flow valve in the collector circuit prevents heat transfer fluid from circulating and transferring heat from To release hot water from the tank thermos, the cold water supply valve must be opened and, of course, the mixing valve must be set to the required temperature to prevent scalding.

The solar collector device reviewed (see literature cited) has the following characteristics, imperfections, and disadvantages.

1. The numerical value of the device efficiency coefficient depends on the temperature difference (T _av -T _g ) _; : where T _av is the average temperature of the heat carrier circulating in the absorber and T _g is the ambient temperature. The larger the difference in temperature, the lower the efficiency of the device. this is particularly true for collectors with open absorbers (without glass), but less so for collectors (expensive), which have a selective coating on the absorber and glass surfaces to reduce collector heat loss. If T _g > T _av , then the numerical value of the efficiency can be greater than 1, since the absorber of the device will absorb both the sun and the heat of the ambient air.

2. The efficiency of a solar collector device depends on the intensity (power) of the solar radiation. The lower the radiation intensity, the lower the efficiency. Therefore, at low sunlight (morning hours, overcast), the device produces only a fraction of the required (potential) heat energy.

3. To provide the consumer with hot water on a regular basis, an additional energy source, such as an electric water heater 9 (Fig.1) located at the top of the tank-thermos or an electric heater 9 placed in a separate, smaller tank-thermos must be used , as shown in Fig.3. In addition to the need for a power source, this is due to the irregular nature of the solar energy flux, as evidenced, for example, by the solar energy histogram recorded in Ulbrok, 2006 (see Figure 2).

August. As we can see, the amount of energy received during the day ranges from 0.6 kWh / m on August 31 to 7.4 kWh / m on 6 August. Solar power was relatively favorable until the 13th, but significantly worse thereafter.

4. During a completely sunny day, solar collectors (Patents LV 13371; LV 13516; LV 13549; LV 13550) heat water to a maximum temperature (60-70 ° C and above) usually in the first half of the day. When the sun's radiation intensity decreases as the sun rises, the collector is automatically shut off from the hot water tank to prevent cooling of already heated water (Felix A. Peuser, Karl-Heinz Remmers, Martin Schnauss. Solar Thermal Systems. Solarpraxis. Berlin, 2002). p.364). As a result, the collector is no longer used, although solar radiation is still sufficient to heat the water at lower temperatures.

The object of the present invention is to increase the efficiency of a solar collector device by reducing its dependence on: the difference between the temperature of the heat carrier circulating in the collector circuit and the ambient air temperature (T _av -T _g ) and the intensity of solar radiation. Thus, the object of the invention is to improve the energy performance of a solar collector device.

The object of the present invention is achieved by intensively transferring heat from the lower region of the tank thermos, which contains the collector circuit heat exchanger (glodene) to the upper area of the tank-thermos from which the hot water is removed, and by separating the two zones with a perforated diaphragm - stratification of the water in the thermo by temperature gradient.

The technically stated objective is achieved (see Fig. 4) by equipping the heat storage tank-thermos of the device with a heat pump having an evaporator 11 located at the bottom of the tank adjacent to the heat exchanger and a condenser 9 located at the top of the tank. The evaporator and condenser areas of the heat pump are separated by a perforated diaphragm 10.

As the unit operates, the collector absorber absorbs solar heat, which is transferred to the glow by the heat carrier. Glodene warms the surrounding water, which in turn is cooled by a heat pump evaporator, preventing the temperature of the water, the glow and the heat carrier from rising. As a result, the unit can operate at a high efficiency, as low heat carrier temperatures reduce heat loss in the collector itself and in the entire heat carrier circuit. During the operation of the heat pump, when the heat carrier vapor condenses, the condenser releases heat which heats the water at the top of the tank-thermos.

The heat pump consumes electrical energy when operating. The heat pump's operating efficiency is characterized by a conversion factor whose numerical value determines the ratio of energy received to consumption. In similar systems, it is usually 3-5.

An important fact to note is that if the temperature of the heat carrier is maintained at ambient temperature, a simple (inexpensive) manifold with an open absorber may be equivalent to an (expensive) selective manifold in terms of energy performance.

Claims (2)

Claims 1. A solar collector device comprising a solar collector, a heat-accumulator tank and a tube that loops the collector's absorber heat carrier duct to a heat-exchanger in the tank-thermocouple, wherein, in order to improve the energy performance of the device, the heat storage tank-thermos is equipped with a heat pump whose evaporator is located in the lower area of the tank-thermos next to a heat exchanger there, while the condenser is located at the top of the tank-thermos, ie the hot water removal area. Device according to claim 1, characterized in that the two zones are separated by a perforated diaphragm inside the container.