Compared to solar hot water, photovoltaic (pronounced: foh-toh-vol-tay-ik) is a relatively new technology. The first photoelectric effect was discovered by Edmund Becquerel, a 19-year old French experimental physicist in 1839. Albert Einstein who received a Nobel Prize in 1923 mathematically explained how the photoelectric effect is caused by absorbtion of light in a 1905 paper. But not until Bell Labs in 1954 did solar PV finally reach a level where its power began to be useful for commercial purposes, such as Western Electric’s dollar bill changer in 1955.

Unlike a solar hot water system, which is essentially a plumbing device, PV uses semi-conductors and sunlight to make electricity. The more solar modules a PV system or array has, the more electricity will be generated. DC electricity can be “inverted” into alternating current (AC), so it can be useable power for a home or business, which can off-set or even eliminate the electric bill.

Learn more about Solar Water Heating (SWH)