First of all, solar thermal systems are not used for generating electricity. Most of the solar you think of today is in the form of photovoltaic panels used for generating electricity. Solar thermal doesn’t operate like that. It uses solar energy to heat an enclosed liquid to the point of evaporation, and collects all of that heat for many uses.

Capturing solar energy as heat (solar thermal) is actually 3-4 times more efficient than trying to capture it as electricity (photovoltaic panels). Because of that it can be a great addition to any building for any of its applications.