Renewable energies play a central role in climate protection. Only with renewable energies can the growing demand for electricity be met while at the same time reducing global CO2 emissions.

But what is meant by renewable energies? What solutions are there? Where do further challenges lie? And what solutions does Bender offer in the energy sector?

Renewable energy sources at a glance

Renewable energies are primarily understood to mean the generation of energy from the sun, wind and hydropower. But biomass and geothermal energy can also be used to generate energy in a way that conserves the earth's resources. Here, the naturally occurring energy flows on earth are used in small parts to generate energy.  A major advantage of renewable energy sources compared to conventional fossil fuels is that they are infinitely available. In addition, the environmentally harmful Co2 produced by burning oil, gas and coal can be dispensed with.

What is solar energy?

Using the sun as a source is the oldest form of energy production on earth. All life on this earth draws its life energy from the power of the sun.
Every year we notice how much power the sun has at the latest on the first summer day at the lake - which ends with the inevitable sunburn. Plants use this power, for example, to grow. With the help of the sun's rays, photosynthesis can be carried out, among other things, and biomass can be produced in the process. In addition, the sun is responsible for wind, rain and clouds and thus has a significant influence on weather patterns on our planet. 
The sun's energy can also be used as a source of electricity and heat. With solar cells in photovoltaic systems or through solar thermal power plants, the sun's radiation can be converted into electrical energy, more precisely into direct current, and used by us technically. 

How does solar energy actually work?

The sun's rays can be converted into electrical energy by various methods and fed into the power grid. There, the energy generated can be used to turn on the lights in the evening.

Probably the best-known way of generating energy from the sun is with the help of photovoltaic systems. These can be found on the roofs of residential buildings or company buildings, but also, for example, on open spaces in the desert.

The solar cells of photovoltaic systems convert sunlight directly into electricity. The solar cell contains a semiconductor consisting of silicone. If the semiconductors are arranged on top of each other according to a certain specification, the "photovoltaic effect" can be used. When sunlight hits the solar cells, free charges (photons) are created that flow off as electrons via an electrical conductor. The direct current generated can be used to operate batteries or electrical devices. When the direct current is converted into alternating current, the energy generated can also be fed directly into the public grid.

Find out how Bender enables safe and reliable operation of photovoltaic systems.

Operate photovoltaic systems safely and with high availability

In a solar thermal power plant, the sun's rays are captured with the help of mirrors. Similar to a burning glass, the light from the sun is captured with the lens. In the process, such a high temperature is generated that highly flammable substances can catch fire. In solar thermal power plants, the heat generated is used to convert the energy into electricity. .

With solar collectors, the energy of the sun can be used to heat water. Similar to the solar cells of a photovoltaic system, the collectors are mounted on the roof of a residential building. Drinking water is heated by the heat of the sun, so that additional electricity can be saved here when taking hot showers. The heated water can also be used for heating systems. A major advantage of solar heating systems is the possibility of storing solar hear from the summer for consumption in the winter.

What is wind energy?

Harnessing the power of the wind is nothing new. Wind was used to drive a mill hundreds of years ago. A great advantage of this energy supplier - it is infinitely available and, unlike the sun, also at night.

In general, wind energy is understood to be the use of the kinetic energy of air currents from which electrical energy is generated. The sun heats the air masses in the atmosphere to different degrees, which leads to pressure differences. Wind is created by the air currents trying to equalise the pressure. The energy of the wind, which is created by the equalisation of pressure, can be captured by wind turbines and converted into electrical energy. How much electricity can be produced depends on the wind strength or wind speed. Therefore, more wind turbines are found in coastal regions. Since 2009, so-called offshore wind farms have also been built directly on the sea. The advantage here is that there are no houses, forests or mountains in the way and so the full wind power can be absorbed.

Find out how Bender helps to operate wind turbines safely and with high availability.

Operate wind turbines safely and with high availability

What is hydropower?

The hydroelectric power plant, or hydroelectric power station, is the second most important technology for generating electricity in the world. Just under 19% of the world's demand can be covered with them. 

The electricity is obtained by passing the water through a constriction. This contains a turbine that is driven by the resulting water pressure. The resulting energy is then converted into electricity. 

In order to generate as much electricity as possible from a hydroelectric power plant, it needs a high water pressure, because the higher it is, the faster the turbine is driven. High water pressure is achieved through great depth and a strong current. These conditions are often found in the mountains and are developed there through human intervention. Dams create a reservoir that is constantly replenished by melt water and rainfall. 

Read here how Bender technology guarantees the availability of the pumped storage power plant in Bad Säckingen. 


The term "biomass" refers to various types of raw materials from which energy can be obtained. For example, from agricultural crops such as maize or rapeseed, fast-growing woody plants or waste from agriculture, households and industry. The biomass can be used in various ways

  • As biogas
  • Biodiesel
  • Pellet/wood logs

Biogas / bio power plant

    The production of biogas is a chemical reaction. For this purpose, animal remains, e.g. from slaughtering, are mixed with plants (maize or rapeseed) - the result is a kind of manure. Millions of bacteria live in the manure and work to decompose the substances. Methane gas is produced in this process, with the exclusion of oxygen. One property of methane gas is that it is easy to ignite. To generate electricity with this approach, the easily flammable methane gas is used to power an engine. The motor can then operate a dynamo, which can ultimately be used to generate electrical energy - i.e. electricity. However, the methane gas can also be converted into natural gas and fed into the natural gas grid. The fermentation residues produced during the process can be used as fertiliser for agriculture.

    How can electricity be stored?

    In the past, there were no concepts for the intelligent storage of electricity. Pumped storage power plants were an exception. There are now new ideas and concepts for electricity storage solutions. In addition to the generation of "green" hydrogen and the emission-free recovery of electricity, these are primarily battery power storage. These will play a major role in the energy sector in the future.

    Read here what is necessary to operate battery energy storage safely and which solutions Bender offers for this.

    Battery energy storage systems (BESS)