Sunlight is the single resource for all of solar energy. However, the amount of sunlight available varies with the time of year, the time of day, and location. For example, some parts of the U.S. are sunnier for greater parts of the year than other areas. In addition, the mechanisms used to gather the energy of the sun can affect the efficacy with which sunlight can be harvested.

Photovoltaic Solar Resource

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Concentrating Solar Resource

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