Good Friday 2018 is on Friday, March 30, 2018 (in 348 days). Good Friday 2017 has already passed: it was on Friday, April 14, 2017 (2 days ago).
What is solar energy? Solar energy is, simply, energy provided by the sun. This energy is in the form of solar radiation, which makes the production of solar electricity possible. Electricity can be produced directly from photovoltaic, PV, cells.
Radiant energy. https://www.sciencedaily.com/terms/radiant_energy.htm. Radiant energy is the energy of electromagnetic waves. The term is most commonly used in the fields of radiometry, solar energy, heating and lighting, but is also used less frequently in other fields (such as telecommunications). The quantity of radiant energy may be calculated by integrating radiant flux (or power) with respect to time and, like all forms of energy, its SI unit is the joule.