Energy from the Sun: How do Photovoltaic Systems work?

The sun emits radiation energy almost constantly, making it a limitless source of energy. The sun's performance potential is so great that it continuously produces 15,000 times more energy than mankind consumes. The development of modern photovoltaic systems has made it possible to harness this renewable energy source. Together with wind energy, photovoltaics form the backbone of the energy revolution. UKA is a provider of both of these cutting-edge technologies and is helping to achieve climate protection goals.

Functionality of Photovoltaic Power Stations

Solar cells use a photoelectric effect to convert energy, and are in turn connected to so-called solar modules. The electricity generated can be used immediately and routed to the public grid.

Components of a Photovoltaic System

The basic components of a photovoltaic system and its mounting system are the solar generator (solar modules), inverter, wiring, meter, and monitoring system (for yield monitoring).

Factors for Optimum Operation

Geographical location: A photovoltaic plant's regional location is a decisive factor in determining the amount of electricity it can generate. The south of Germany is especially well suited for power generation using photovoltaic systems. Peak values are achieved as a result of strong solar radiation. Northern Germany is also ideally suited for solar power generation because of the high wind speeds resulting in more efficient cooling of the solar modules.

Hours of sunshine: Even in "low-radiation" Germany, the amount of energy emitted by the sun, at 900 to 1,100 kWh per square metre, is still 200 times higher than the primary energy consumption of the entire German population.

Irradiation angle of the sun on the modules: To achieve the highest annual energy yield in Central Europe, it is ideal to position the modules to the south with an inclination angle of about 30 to 35 degrees to the horizon. A somewhat higher tilt angle ensures that the system is optimally aligned twice a day - in the morning and afternoon and twice a year - in May and July.


The sun generates an inexhaustible amount of energy. It is possible to harness this potential and benefit from it thanks to state-of-the-art photovoltaic systems. The result is clean, green electricity, which contributes to the energy revolution.

In 2018, photovoltaic (PV) systems generated 46 TWh of electricity, covering around 8.7 per cent of net electricity consumption in Germany, based on the previous year's consumption figures. The total share of renewable energies (RE) amounted to approximately 43 per cent. In terms of gross electricity consumption, PV accounts for around 7.7 per cent and all renewables for around 38 per cent. PV electricity can periodically cover up to 45 per cent of our current electricity consumption on sunny workdays and up to 60 per cent on Sundays and public holidays (source:Frauenhofer ISE).

Land Usage

PV systems are often installed in areas that have previously been contaminated, for example by military, economic, traffic or residential use, areas along motorways and railway lines (in 100-metre strips), areas designated as commercial or industrial areas or impervious surfaces (former landfills, car parks, etc.).

If photovoltaic systems were to be installed on agricultural land, not currently encouraged in Germany, there could be competition for use. In this context, however, it is important to note that solar parks have a much higher energy yield than bioenergy generation across the same area. Solar parks, for example, supply 25 to 65 times as much electricity per unit area as energy-yielding crops.