Status: 06.10.2022 18:05
In Germany, more energy is to be generated with the help of solar systems – the potential of solar power is still underused. But for that, bureaucratic hurdles would have to be dismantled and staff gaps filled.
From April to October, Tobias Bücklein does not need any external electricity for his house in Konstanz. Den produces his solar system on the roof. There is also battery storage for at night or when the sun doesn’t shine for a few days.
When Bücklein decided in favor of the solar system in 2017, the most difficult thing was the bureaucracy. “I found it to be such an enormous effort that you actually didn’t feel like doing it anymore,” says the homeowner. A building permit is usually not required, but the building law is different in all 16 federal states. There are also tax issues, registration with the Federal Network Agency and the network operator. He buys the excess electricity that is fed into the grid by the solar system.
Traffic light coalition wants to facilitate the way to the in-house solar system
The goal of the traffic light coalition of SPD, Greens and FDP is that more roofs are used for photovoltaics. As an important building block to expand renewable energies – for climate protection and more independence in energy issues.
That is why the federal government has decided on a new version of the Renewable Energy Sources Act, which should make it easier to install a solar system on your own roof. Among other things, network operators must provide a portal for inquiries from 2025. The feed-in tariff will also be increased, so there is a little more money for the self-generated electricity.
Only ten percent of the roof area has been used
And there is a lot of potential on the roofs: According to an analysis by the market research company EUPD Research, more than ten million single-family homes are suitable for solar systems. In addition, there are apartment buildings, office and industrial buildings – so far only around a tenth of the roof areas are used.
In the coalition agreement between the SPD, the Greens and the FDP, there is a plan that solar roofs should become mandatory for new commercial buildings and the rule for new private buildings. There is still no federal law, but the first federal states have introduced it: In Baden-Württemberg, new residential buildings have had to be equipped with a solar system since May. Berlin and Hamburg will commit to this from 2023, Lower Saxony from 2025.
Important building block for German energy targets
But what is the use of solar systems on all roofs? “We assume that we can cover around ten percent of Germany’s energy requirements with the roofs alone,” says Volker Quaschning, professor at the Berlin University of Applied Sciences.
So that alone is not enough to get the energy transition going. However, the proportion of solar roofs is necessary if Germany wants to achieve its expansion goals: by 2030, 80 percent of gross electricity consumption should come from renewable energies. “All in all, in Germany we have to cover about a third with solar technology. That means we have to increase tenfold what we are currently doing,” explains the professor for regenerative energy systems. In addition, of course, wind power and networks need to be expanded, according to Quaschning. Significantly more storage capacity is also needed when the sun isn’t shining for a long time and the wind isn’t blowing.
Solar power from the field
Small solar systems on every roof can only be an addition, according to Andreas Luczak, a professor at the Kiel University of Applied Sciences: “In most cases, the large system on the open area is more economical.”
This fuels fears that solar investors will in future contest the fields in agriculture. But there are also ideas for combining both: with solar modules on greenhouses or with the help of systems built on high scaffolding, under which the fields can continue to be tilled. According to the Fraunhofer Institute for Solar Energy Systems (ISE) in Freiburg, so-called agri-photovoltaics have enormous potential. With solar systems, the areas could be used more efficiently than with corn or other energy crops, from which so-called biofuel is produced.
An industry with profit potential
In addition to roofs and fields, many places in urban areas can also be used for solar power: from covered squares to noise protection walls and facades, which the Helmholtz Center Berlin for Materials and Energy is researching. A laboratory building clad on three sides with solar modules generates enough energy per year to power six single-family houses. But the costs for solar facades are high and the roof systems are much more efficient.
Above all, however, it depends on the material and personnel at the moment: the waiting time for a solar system is currently several months. In addition, there is a lack of specialists in engineering offices and in the trades. The specialization and expansion of production in this country can be worthwhile. If our energy system were to switch to renewable energies, it would take 40 million solar panels a year to keep the systems running. This is how the Fraunhofer Institute ISE calculated it. This can earn several billion euros.