Solar energy is energy from the sun in the form of radiated heat and light. The sun's radiant energy can be used to provide lighting and heat for buildings and to produce electricity. Historically, solar energy has been harnessed through passive solar technologies. Typically, these involve the strategic location of buildings and various elements of these buildings, such as windows, overhangs and thermal masses. Such practices take advantage of the sun for lighting and space heating to significantly reduce the use of electrical or mechanical equipment. Solar energy can be harnessed only during the day and only if the sunlight is not blocked by clouds, buildings or other obstacles.

Today, two active solar technologies that involve electrical or mechanical equipment are becoming more common. First, solar collectors or panels are used to heat water or ventilation air for use in buildings. Second, solar photovoltaic technology uses solar cells to convert sunlight directly into electricity.

Tanzania enjoys abundant sunlight, with an average annual solar radiation levels in the range between 4.2 to 5kWh/m2 per day, thus making the use of solar electricity an attractive alternative.