How much energy does a solar panel produce

Lot of spikes about energy and the use of natural energy resources like solar panel, so do you wanted to know how much energy does a solar panel produce?

Solar energy is the energy obtained by capturing the light and heat emitted by the Sun .

In approximate calculation a big solar panel can produce 120 MW per day . Since it emerged he described as the perfect solution for the energy needs of all countries due to its universality and free because, as mentioned above, comes from the sun. For users spending is in the process of installing solar equipment (plate, thermostat …). This expenditure, over time, is declining so we are not rare to see in most houses the installed tiles. We can say that does not pollute and that their capture is straightforward and easy to maintain.

The solar radiation that reaches the earth can be exploited by means of heat which occurs through absorption of radiation, for example, optical devices or other. It is a so-called renewable energy , especially clean group, known as clean energy or green energy , but at the end of its life, the panels photovoltaic clean can be a difficult recyclable waste today.

The power of radiation varies by time of day that the weather conditions and latitude. It can be assumed that in good radiation value is approximately 1000 W / m² at the surface. This power is known as irradiance .

The radiation is usable in direct and diffuse components, or the sum of both. Direct radiation is the focus that comes directly from the sun, without intermediate reflections or refractions. The diffuse is issued by the daytime sky due to multiple reflection and refraction phenomena in the solar atmosphere, clouds and other atmospheric and terrestrial elements. Direct radiation can be reflected and concentrated for use, while it is not possible to concentrate the diffused light coming from all directions.

The direct normal irradiance (or perpendicular to the sun) outside the atmosphere, called the solar constant and has an average value of 1354 W / m² (corresponding to a maximum value at the perihelion of 1395 W / m² and a minimum value at aphelion of 1308 W / m² ). The Earth receives 174 petawatt incoming solar radiation ( insolation ) from the uppermost layer of the atmosphere . Approximately 30% is reflected back to space while the rest is absorbed by clouds, oceans and land masses . The electromagnetic spectrum of sunlight on Earth’s surface is mainly occupied by visible light ranges and infrared with a small amount of ultraviolet radiation . The radiation absorbed by the oceans, clouds, air and land masses increase the temperature thereof. The heated air is the one containing evaporated water that rises from the oceans, and in part of the continents, causing atmospheric circulation or convection . When the air rises to the upper layers, where the temperature is low, its temperature decreases until the vapor condenses into water clouds. The latent heat of water condensation amplifies convection, producing phenomena like wind , storms and anticyclones . The solar energy absorbed by the oceans and land masses keeps the surface at 14 ° C. For the photosynthesis of green plants convert solar energy into chemical energy, which produces food, wood and biomass , which also derived from fossil fuels.

It is estimated that the total energy absorbed by the atmosphere , oceans and continents can be 3,850,000 EJ per year. . In 2002, this energy in a second equivalent of total world consumption of energy for a year. The Photosynthesis captures approximately 3,000 EJ per year in biomass, which represents only 0.08% of the energy received by the Earth. The amount of annual solar energy received is so vast that is roughly twice the energy produced by other sources ever non-renewable energy such as the oil , the coal , the uranium and natural gas.

Typical yields of a photovoltaic cell (isolated) from polycrystalline silicon oscillate about 10%. For monocrystalline silicon cells, the values ??range in 15%. The highest achieved with solar thermal collectors at low temperature (which can reach 70% efficiency in energy transfer solar thermal).

Also solar thermal energy of low temperature, with the newly developed system, around 50% in their latest versions. It has the advantage that it can work 24 hours a day based on stored hot water during daylight hours.

The photovoltaic panels are, as we have seen, a yield of around 15% and do not produce heat that can be reused, although there are lines of research on hybrid panels for generating electricity and heat simultaneously. However, they are well suited for simple installations on rooftops and self-sufficiency , rural electrification projects in areas that lack grid-although its price is still high. To encourage the development of technology to achieve parity-match the price of obtaining energy to other cheaper sources today, there are production subsidies, which guarantee a fixed purchase price by the mains. This is the case of Germany , Italy or Spain.

Also studied to obtain energy from photosynthesis of algae and plants , with a yield of 3%.

According to a study published in 2007 by the World Energy Council , by 2100 70% of energy consumed will be of solar origin. According to reports from Greenpeace , the PV can provide electricity to two thirds of world population in 2030 .

Although most reviews are positive, the solar panels also have some criticism as Robert Huber, Nobel Prize in Chemistry in 1988 for his studies on photosynthesis who during his speech at the Forum Joly showed their opposition to the plant cell photovoltaic saying ‘can not cover a fertile country with solar panels. Photovoltaic energy is five times more expensive than hydro. ‘