Solar water air conditioning is a high-efficiency solar air conditioner developed by JDSOLAR researchers to maximize energy savings and reduce energy consumption.
JDSOLAR solar air conditioning system takes into account the application of heating and cooling. It is an ideal application for comprehensive office, guest house, school, hospital, swimming pool, aquaculture and family. In winter and even throughout the year, heating is required, such as domestic hot water, heating, swimming pool water heating and temperature regulation, etc., while the summer needs a cold world, with solar water heating, is a central air conditioner. At present, countries all over the world are stepping up research on solar air conditioning technology.
According to the survey, countries and regions that have established or are in the process of establishing solar air conditioning systems include Italy, Spain, Germany, the United States, Japan, South Korea, Singapore, and Hong Kong. This is because air-conditioning energy consumption in developed countries accounts for a large proportion of civil energy consumption in the whole year. The use of solar-powered air-conditioning systems is of great significance for saving conventional energy and protecting the natural environment.
Principle of refrigeration
The so-called solar cooling is the use of solar collectors to provide the absorption medium of the heat medium required by the generator. The higher the temperature of the heat medium water, the higher the coefficient of performance (also known as COP) of the refrigerator, so that the refrigeration efficiency of the air conditioning system is also higher. For example, if the temperature of the heat medium water is about 60 ° C, the COP of the refrigerator is about 0 to 40; if the temperature of the heat medium water is about 90 ° C, the COP of the refrigerator is about 0 to 70; if the temperature of the heat medium is about 120 ° C, the refrigerator The COP can reach 110 or more.
Practice has proved that solar air conditioning combined with heat pipe vacuum tube collector and lithium bromide absorption chiller has opened up a new application field for solar thermal utilization technology.
When heating is required in winter, the superconducting solar collector absorbs solar radiant energy and is transferred to the composite superconducting energy storage converter via superconducting liquid. When the temperature of the heat storage system reaches 40 °C, the central temperature control system automatically issues a heating command, so that the indoor cooling and heating dispersion system is in a heating state, and the hot air is output through the air outlet. When the room temperature reaches the set temperature value, the output of hot air is stopped. When the temperature of the room is lower than the set value, the air outlet outputs hot air, so that the automatic circulation reaches the purpose of heating (the temperature setting of each room is independent, not mutually influences). In the case of continuous cloudy days, when the solar energy is insufficient, the biomass heat energy generator is put into use to supplement the shortage of solar energy.
Solar air-conditioning refrigeration systems have been continually intensively researched because of their energy-saving, clean and pollution-free features. With the continuous improvement of application technologies such as materials, working fluids, process manufacturing and design of solar collectors and refrigeration systems, the application of solar air conditioning refrigeration devices will be widely used. An air conditioner using solar energy as an energy source can generally be divided into three parts:
One is a solar collector. Collectors come in a variety of forms and have different performances. The collector adopts the most vacuum tube type, and the most basic types of vacuum tube type are: heat pipe type vacuum heat collecting tube (referred to as heat pipe), all glass vacuum heat collecting tube and straight-through vacuum heat collecting tube. The heat pipe vacuum heat collecting tube is a high-tech energy-saving product developed after the traditional flat-plate vacuum heat collecting tube. It integrates heat pipe technology and vacuum technology, and increases the working temperature of the solar collector from 70 ° C to over 120 ° C. It greatly improves the thermal performance of the collector and is an ideal product for warm utilization.
The second is the refrigeration system. A refrigeration system that uses a low-temperature heat source as a power is different from a compression-type refrigeration system. It must be able to fully utilize the low-temperature heat source as a power. At present, the absorption refrigeration technology is relatively mature. Absorption refrigeration uses lithium bromide-water, ammonia-water, etc. as the working medium pair, which has good economical efficiency, especially the use of lithium bromide-water as the working medium pair, which can meet the air conditioning device with high safety requirements. The ideal working quality pair.
The third is an automated control system, a control system that controls and secures various operating parameters of the device. Absorption refrigeration and air-conditioning systems with heat pipes as solar collectors and lithium bromide-water as working fluids, both as large-scale air conditioners with large refrigeration capacity and as household air conditioners, have practical significance and development prospects, especially the current awareness of environmental protection. The improvement of the environment and the increasing requirements for the environment, non-polluting, low-energy, air-powered air-conditioning will be favored by people.
When the sunlight hits the heat absorption sheet in the vacuum tube, the working medium in the heat pipe is vaporized by heat boiling, the steam continuously rushes to the condensation end of the top, and condenses into a liquid at the condensation end, and the condensed working medium flows back along the pipe wall to the evaporation section of the heat pipe. , complete a loop. Such a heat pipe which absorbs heat at one end and condenses heat at the other end, and realizes heat transfer by internal phase change, is accustomed to be called a gravity heat pipe. There is no heat absorbing core inside the heat pipe. The condensed liquid returns from the condensing section to the evaporation section. It relies on the gravity of the condensate itself and does not need external power to automatically circulate. This is the heat collecting process of the heat pipe type vacuum tube. Since the heat pipe relies on gravity to circulate the working fluid, the evaporation section must be placed below the condensation section in use. If the evaporation section is placed above the condensation section, gravity will hinder the reflux of the condensate, and there is no power to return the condensate to the evaporation section, and the heat pipe will not work. Therefore, the heat pipe can also be called a heat transfer diode for one-way heat transfer. This characteristic of the heat pipe is very suitable for solar collectors, which can transfer the absorbed solar heat to the water tank, heat the water, and reverse the irreversible. That is to say, it absorbs heat during the day and does not release heat at night. This is very beneficial for reducing the heat loss of the collector and improving the thermal insulation performance of the collector.
Since the heat pipe mainly relies on the absorption and release of latent heat during the phase change of the working fluid and the heat transfer of the steam flow, the latent heat of vaporization of most working fluids is large, so that a large amount of heat can be transferred without requiring a large amount of evaporation. When the steam is in a saturated state, the temperature difference between the flow and the phase change is small, and the wall of the tube is relatively thin, so the surface temperature gradient of the heat pipe is small. When the heat flux density is low, a highly isothermal surface can be obtained to increase the thermal conductivity. The installation angle of the heat pipe has a certain influence on the heat transfer performance.
JDSOLAR large-scale solar air conditioning system consists of heat pipe vacuum tube collector, lithium bromide absorption chiller, hot water storage tank, cold storage tank, domestic hot water storage tank, circulation pump, cooling tower, air conditioning box, auxiliary fuel boiler and automatic control The system is composed of parts.
The seasonal adaptability of JDSOLAR solar air conditioners is good, that is to say, the cooling capacity of the system increases with the increase of solar radiant energy, which is exactly the urgent requirement for air conditioners in summer.
Conventional compression chillers use Freon as a medium, which has a great destructive effect on the atmosphere. The chiller uses non-toxic, harmless water or lithium bromide as a medium, which is very beneficial to the environment;
The solar air conditioning system combines summer cooling, winter heating and hot water supply in other seasons, significantly improving the utilization and economy of the solar system.
The solar air conditioning system can exert the comprehensive advantages of summer cooling, winter heating and hot water supply throughout the year, and it will surely achieve significant economic, social and environmental benefits, and has broad application prospects.