This system can consist of either flat plates or tubes. The water heats up in the sun and is then pumped into the house for use. For many people this is the most cost-effective solar power solution.
Another thing you can do with the sun's thermal energy is heat up your swimming pool with a
solar swimming pool heater
. The pool water is heated in rooftop panels like in the hot water example above but instead of being pumped into the house the water circulates back to the swimming pool. Many people extend their swimming season this way.
Solar thermal energy is also used to produce electricity but in a much different way then the solar panels on most people's roofs.
Rather than using the sun's light like those photovoltaic panels (photo = light, voltaic = electric), solar thermal uses mirrors to concentrate the sun's heat and boil water which turns a turbine and generates electricity.
One way this is done is by having multiple mirrors focused on a solar power tower (heliostat) where water is heated to turn a turbine.