When one switches from conventional energy sources to the solar powered energy sources the appliances need to be developed so as to adapt it. In order to heat the water using the solar power one needs solar powered water heater. New adjustments can be made on the existing power heater to convert it to Solar Water Heater.
There are several options to heat water by using solar power. One can even design their own Solar Water Heater to heat water. As Water runs through pipes before entering our homes. If the water is heated at that stage using the Solar Water Heater then that can be helpful. Water stored in tanks can also be heated using solar power. One needs storage tanks and solar collectors to heat the water.
Solar water heating system generally consists of solar thermal collectors, fluid system which moves the heat from the collector to its point of usage, reservoir tank to store the heat which can be reused. Heat is stored in larger water tanks so that they can function properly even in case of bad weather. Also the optimum final temperature for the absorber is lower than the typical immersion or combustion heater. The collector can carry fluid that is to be heated. This fluid can either be water or any solution such as antifreeze which will prevent water from freezing. Heat is delivered to the tank using a heat exchanger (a coil of copper tubing withing the tank). In next step water flows through tubes to absorber plate. Absorber plates are painted black so as to absorb the sunlight. Once the collector is heated it will heat the fluid or water that passes through the tubes. When water passes through these tubes it goes into the storage tank. Heated water is held by the storage tank. This storage tank is usually insulated so that it can keep the water warm for the long time. Then water flows into home on demand.
Solar Water Heaters are of two types: Active Solar Water Heater and Passive Solar Water Heater.
Active systems or Pumped systems:
Active solar water heating systems use pumps or other mechanical device that can move the water between the flat plate collector and the storage tank. These systems are more quick and efficient. In these there are low carbon systems or zero carbon systems. In Europe most the systems are of low carbon type.
Passive systems or Compact systems
Compact systems depend on gravity to feed the water from the flat plate collector to the storage tank. Compact systems may be slow at times and may not be sufficient enough to keep up with the demand. Passive systems can save up 4.5 tonnes annually of greenhouse gas emissions.
These Solar Water Heaters can produce amazing results in some climates. In most of the European nations the Solar Water Heaters provide around 15 to 20 % of the domestic heating