Solar absorption air conditioning
When do you need air conditioning? When it is hot and sunny. This is why Broad Air Conditioning, China, one of the world's largest manufacturers of direct-fired absorption chillers, has been focusing on solar absorption air-conditioning systems and now plans to commercialize them worldwide. The system consists of a hot water and direct-fired absorption chiller, a heat collector and an energy storage tank. Sunlight is constantly tracked to be concentrated on vacuum tubes through reflectors so that the circulating water in the tubes is heated to 180°C. After the heat source water releases its heat to high-temperature generators, it is pumped to a heat collecting tube to be heated and the cycle starts all over again. During solar heating operation, when the collector cannot collect adequate heat due to reduced light intensity, the system can change the heat source water flow rate by modulating pump frequency to keep the water at 130°C and, at the same time, start the burner to make up the needed heating capacity. When the heat collecting capacity of solar collector is larger than the required cooling load, the surplus heating or cooling can be stored by the energy storage tank. When sufficient sunlight is unavailable, on rainy days or at night, the stored cool or hot water can be provided from the storage tank to system, or the unit operates in cooling/heating mode as a normal direct-fired chiller. Such a system installed in Tianjin Hi-Tech Information Center, a 120 000 m2 building in Tianjin, China - 3000-3200 hours of sunlight a year - enabled savings of 4000 MWh electric power for refrigeration and 500 000 m3 of gas for heating in a single year.