Solar does have limitations to the design. Solar is usually
offered to provide cost savings as well as for environmental
reasons. High-wattage fixtures require a much larger solar
panel that may not be able to be a self-contained unit.
Solar is not usually able to operate a light fixture
cost-effectively in order to meet light-level requirements
for banks, car lots, or large six-lane highways.
Applications, where solar is feasible, are standard parking,
minimum security parking, perimeter areas, and two to
four-lane roadways (.20 min to .50 min foot candle).