Using electricity, including solar electricity, to heat water is not energy efficient and therefore unnecessarily expensive. Solar water heating systems (solar thermal technology) are good alternative.
Solar thermal systems are used to heat water for households and for larger hot water consumers such as hotels and hospitals.
The main categories of solar collectors used are:
- Flat plate collectors.
- Evacuated tubes (these are more efficient and need less roof space, but are generally more expensive).
Domestic solar water heating system with evacuated tube collectors. Water is heated during the day and stored in the tank.
Large solar water heating system with evacuated tube collectors.
Solar thermal technology can also be used to provide process heat for industry, heat for electricity-generating solar power plants, cooling for large sorption air conditioning systems and cooling for industrial and agricultural applications.