What is photoelectric solar energy and how does it work?
Photovoltaic solar energy directly transforms sunlight into electricity using a technology based on the photovoltaic effect. By affecting the radiation of the sun on one of the faces of a photoelectric cell (which make up the panels) there is a difference of electric potential between the two faces that causes the electrons to jump from one place to another, thus generating electric current.
There are three types of solar panels: photovoltaic, energy generators for the needs of our homes; thermal, which are installed in houses with direct reception of the sun; and thermodynamic, that work in spite of the meteorological variation, that is to say, even if it is at night, it rains or it is cloudy.
In the early stages of photovoltaic technology, this type of energy was used to provide electricity to satellites. It was in the 50’s, says the APPA, when photovoltaic panels accelerated their development to become, at present, an alternative to the use of fossil fuels.
What are the benefits of photovoltaic energy?
The electrical energy generated by photovoltaic solar panels is inexhaustible and does not pollute, so it contributes to sustainable development, as well as favoring the development of local employment. It can also be used in two different ways: it can be sold to the grid or it can be consumed in isolated locations where there is no conventional electricity grid.
Therefore, it is a particularly suitable system for rural or isolated areas where the power line does not reach or is difficult or expensive to install or for geographic areas whose climatology allows many hours of sun per year.
The cost of installation and maintenance of solar panels, whose average useful life is greater than 30 years, has declined ostensibly in the last years, as the photovoltaic technology develops. It requires an initial investment and small operating costs, but once installed the photovoltaic system, the fuel is free and for life.
SUMMARY OF PHOTOVOLTAIC ENERGY BENEFITS:
Scalable from large plants to home systems
Suitable for rural or isolated areas
Contributes to sustainable development
Encourages local employment
More data on photovoltaic solar energy
Solar energy will become the cheapest source of electricity in many parts of the world in the context of a continued decline in the cost of photovoltaic panels over the next ten years, according to International Business Time echoing research by the ‘ think tank ‘German Now Energiewende.
Since the 1980s, panels to generate electricity from the sun have been getting cheaper by 10% per year. A trend that would enable this technology to meet in 2027 20% of global energy needs.
Fortune, a reputed business magazine, collects a study that ensures that by the end of 2016 solar energy will offer more new jobs than the oil sector. In the US, says The Solar Foundation, 2015 marked the third consecutive year of job growth in the solar sector.
The world market for photovoltaic energy is expected to increase by about 20% in the next two years, adding at least 60 GW in 2016 and more than 70 GW in 2017, according to a PV Market Alliance study. This same organization anticipates that demand will remain bullish, mainly due to strong growth in India, China, the United States and several emerging markets.
In fact, according to PVMA -data grouped on the renewable energy website-, the integration of 51,000 MW made it possible to surpass a new record of photovoltaic power installed in the world in 2015, with Asia as the first continent in photovoltaic installation that year (thanks to the bet of China and Japan).
What is the difference between peak and nominal power in photovoltaic?
Peak power refers to the amount of kW installed, while the nominal power refers to the power of the inverter (the electrical equipment that transforms the energy generated by the panels into a suitable one for consumption).
In principle, the nominal power is the one that marks the limit (you can not produce more than what the inverter can convert). Nevertheless, photovoltaic installations always install a peak power higher than nominal – more panels – to try to cover 100% of the capacity of the inverter.
A plant will be well designed if the peak power – panels installed – is the ideal one to ensure that the inverter is able to operate at 100% capacity at all times when it is required.