How does photovoltaics work?

How does photovoltaics work? 4

Photovoltaics uses the natural energy of the sun, the centre of our universe, whose energy is available to everyone free of charge. The climate-friendly technology makes it possible to become largely independent of the price rounds of the energy suppliers. The electricity generated from solar energy can either be used by oneself or fed into the power grid. Solar power is also environmentally friendly in generation - and the energy source is available almost indefinitely. For these reasons, photovoltaics have come back into the public eye and can now fully exploit their advantages. In the following, you will learn how photovoltaics works, what the advantages and disadvantages of the technology are and what in particular needs to be considered.

How does sunlight generate electricity?

The technology to generate electricity from sunlight is based on the so-called photovoltaic or photoelectric effect. Since solar radiation is best captured on roofs, it usually takes place there. Whether a small solar system on a single-family home or an industrial plant - the photovoltaic system always works the same way in principle: the sunlight falls on the solar cells, which generate direct current from it. The semiconductor materials in the solar cells, which are usually made of silicon, excite electrons. These subsequently move and generate electricity through the kinetic energy.

The individual solar cells - the essential component of a photovoltaic system - are interconnected to form larger solar modules, which in turn are interconnected to form the solar generator. The inverter converts the direct current generated into alternating current. The energy manager then feeds this directly into the public or private electricity grid via power cables. When feeding into the public grid, a meter ensures correct billing.

The low or medium-voltage grid, into which the generated energy is fed, then forms the energy storage. As a rule, feed-in and consumption do not run synchronously in one's own house. Regions without a grid connection use so-called island systems with energy storage in the form of a battery.

The rule is: the more the sun shines, the more solar power can be generated.

Advantages of photovoltaics

Photovoltaic systems operate silently, require little maintenance and have a service life of more than 20 years.

Energy

Apart from the fact that solar energy is freely available, photovoltaic systems produce electricity even when there is little sunlight. They also enable a power supply that is independent of large electricity providers. The fact that most of the electricity is consumed where it is generated relieves the strain on the electricity grids and tends to ensure that fewer high-voltage lines need to be built to transport the electricity. The electricity produced can also be used at night and/or in bad weather by means of solar storage. An electric car can also be combined well with a photovoltaic system.

Environment

Environmentally friendly electricity displaces nuclear or coal-fired electricity, because for every kilowatt hour of solar power, the same amount of conventionally generated energy is produced less. This accelerates the energy turnaround and is thus also active action against global warming. Photovoltaic systems run without CO² emissions, which reduces the consumption of fossil fuels (oil and gas).

In addition, transport routes for fossil and renewable (wood) fuels are eliminated with a photovoltaic system. The energy required to produce electricity and the energy produced by the solar system pay for themselves after a few years.

Investment

Thanks to government subsidies and possible loans, it does not take too long for the investment in a photovoltaic system to pay for itself. In addition, surplus electricity is subsidised by the photovoltaic feed-in tariff and the running costs are quite manageable. These factors mean that the purchase costs soon pay for themselves - although the actual length of time depends, of course, on the individual circumstances. In the long run, the environmentally friendly aspect also stands to benefit us all.

Disadvantages of a photovoltaic system

Where there is light, there is also shadow, and this literally also applies to photovoltaics - even if the advantages outweigh the disadvantages overall. The inverter plays a decisive role here. Opinions on its service life vary widely, but realistically it can be assumed that it will have to be replaced at least once. This may be necessary after ten, 15 or 20 years.

Energy

The output of a photovoltaic system depends on the location, so the following applies: the further south the system is located, the more electricity is produced. Solar modules do not work without sunlight. If the weather is permanently bad, you are no longer as independent of electricity generated elsewhere as you might have wanted.

Environment

Even though the environmental friendliness of the electricity produced by a photovoltaic system is always brought to the fore, the production of such a system requires a relatively high energy input.

Investment

The initial investment in a photovoltaic system is comparatively high, with the solar modules accounting for two thirds of the investment. It is true that the sun is an inexhaustible and free source. However, the generation of solar electricity is by no means free. Even though photovoltaic systems have become considerably cheaper in recent years, you still have to invest a high four-digit sum for the technology and the installation. It can take more than ten years for the price to be recouped. Therefore, before deciding on a photovoltaic system, one should obtain exact information and consult experts who provide truthful information about advantages and disadvantages.

About the author

TRITEC has specialised in the generation of solar power through photovoltaics for over 34 years. We are active worldwide in both photovoltaic wholesale and large-scale plant construction. In addition to our proven PV mounting system, we also offer our own intelligent system solutions for the planning, design and performance control of photovoltaic systems, as well as branded products from leading photovoltaic manufacturers.