Introduction to Solar Refrigerator
The solar refrigerator is the refrigeration system that runs on the solar energy. The solar refrigerator comprises of all the traditional components like the compressor, condenser, expansion valve and the evaporator or the freezer. The power is supplied not by the domestic electrical supply system, but from the solar panel.
The solar system of the solar refrigerator comprises of the solar panel that collects the solar energy. The solar panels are fitted with photovoltaic cells that convert the solar energy into electrical energy and store it in the battery. During the normal running of the solar refrigerator the power is supplied directly by the solar panel, but when the output power of solar panels is less, the additional power is supplied by the battery. The battery is recharged when excess amount of power is produced by the solar panels.
The output supply of the batteries and the solar panel is DC with voltage of about 12. A typical solar system produces 300W or 600W of power depending upon the size of the desired refrigerator. The voltage regulator is connected to the battery to convert the low voltage DC supply to high voltage AC supply to run the compressor. It is advantageous to use the AC supply compressor since it can run on domestic electrical supply also. Some of the solar refrigerators use compressors that can run directly on DC supply.
Another application where the solar energy can be very useful is the vapor absorption refrigeration system. In these systems heat from the steam is used to heat water mixed with lithium bromide or ammonia that act as the refrigerant. In these machines, the heat produced by the steam can be replaced by the heat produced by solar energy.