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This section lists the FAQ (Frequently Asked Questions) on photovoltaic systems and in general the sources of renewable energy.

Glossary of solar energy

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 [3] Glossary of solar energy
Solar energy  [2][-]  --
Glossary of solar energyfaq: 1500

refraction of sunlight by the surrounding environment, is the reflected radiation.

is the angle above the horizon the sun’s position compared to the south, south is 0 °, -90 ° and east and 90 to west.

angle of declination
angular position of the sun than the equator.

angle of elevation
angular distance of the sun over the plan horizon.

angle between the perpendicular to an inclined plane and a ray of light that strikes it.

Hour Angle
angular distance between the straight line joining the earth and the sun at noon and the sun itself, this angle changes every hour of 15 ° and is expressed by omega = 15 (12-ts) (ts Standard Time).

Solar radiation
is the instantaneous solar radiation, then a power (electromagnetic type), which is emitted by the sun according to the Stefan Boltzmann (depending on the external temperature of the sun itself, about 6000K), its intensity or solar flux is almost constant outside the atmosphere and that is 1353 W/m2. The radiation at the equator in optimal conditions is about 1000 W/m2.

Insolation global
represents the total radiation received from the solar system, considering the sun, the weather and environment.

instrument used for measuring global solar radiation.

instrument used to measure the direct solar radiation.

Solar radiation
represents the electromagnetic energy emitted by the sun that reaches the ground, it is measured in kWh/m2.

Global radiation
is the sum of direct radiation and diffuse radiation of albedo.

direct radiation
is the part of radiation with a defined angle of incidence, which directly affects the surface of the solar panel.

scattered radiation
is the part of solar radiation was reflected and scattered by the atmosphere and reaches a solar panel.

Cathodic protection
system of protection against corrosion of metal pipelines. The latter are obliged to u negative potential than the surrounding soil, reducing the corrosion of the material that composes it.


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