"Bottlenecks at times"

Solar boom puts a strain on German power grids

More and more PV systems are producing and storing more and more electricity - but there is still a lack of efficient distribution and control.

(Bild: stock.adobe.com)

The solar boom in Germany is making it increasingly difficult to control the electricity grids. According to an analysis, solar power generation is heavily concentrated around midday on sunny days. "This can lead to temporary bottlenecks in the electricity grids, especially at the distribution grid level."

The German Institute for Economic Research (DIW) in Berlin reported that existing flexibility in the grid integration of photovoltaics (PV) is not always used optimally. For example, many PV systems have recently been installed in buildings in combination with battery storage systems. These allow households or businesses to increase the proportion of PV electricity they use themselves.

"However, there are hardly any incentives to use these storage systems in a grid- or market-oriented manner, as neither the feed-in tariff nor, as a rule, the household electricity tariffs provide the corresponding signals: Remuneration and prices are the same for every kilowatt hour, regardless of the current market price," the study states.

More smart meters needed
This could, for example, lead to a situation where the PV storage systems are already fully charged in the summer months during the hours of highest PV generation and the systems then feed full power into the grid. This puts a strain on the local electricity grids. According to the study, more speed is needed in the installation of "smart" electricity meters in order to control electricity grids more efficiently.

The expansion of solar installations has clearly picked up speed. According to figures from the Federal Network Agency, the number of new installations doubled last year compared to the previous year to almost 14 gigawatts. According to the Ministry of Economic Affairs, the total output of installed solar systems amounted to more than 90 gigawatts at the end of June. This means that the German government's target of 88 gigawatts of installed capacity by 2024 has already been reached. By 2030, the installed capacity should then be 215 gigawatts.

Heavily dependent on imports from China
In order to achieve this expansion target, the speed must increase even further, according to the DIW study. The main driver of expansion is currently a strong increase in smaller PV systems on buildings, which are attractive due to the advantages of self-consumption. "Alongside a lot of light, however, there is also shadow: There is still potential for ground-mounted systems." One of the main reasons for the recent strong growth is the fall in prices for solar modules.

In recent years, very large production capacities have been built up, particularly in China. However, these are currently far from being fully utilized, which is putting pressure on module prices. China dominates the global PV production chain. The expansion of PV therefore has another "downside". As there is hardly any production of solar cells in Germany or the EU, further expansion is heavily dependent on imports from China.