Navigating Solar Power: Adapting as a Photovoltaic System Owner
The duty of proprietors who manage photovoltaic installations
Embrace the shifting landscape of solar power as new regulations come into play. This article highlights key changes for PV owners due to the Solar Peak Law.
Generating renewable energy through a photovoltaic system is affected by factors such as weather and sunlight. In Germany, excessive electricity production during peak sunlight hours can momentarily strain the power grid. To address this issue, the recent Solar Peak Law has been enforced since late February 2025. The goal is to disperse solar power more evenly throughout the day across the grid, eradicating "power peaks" at midday.
The core principle of the law is that newly installed photovoltaic systems with a capacity of seven kilowatt-peak (kWp) or more can unlimitedly feed in electricity only when equipped with an intelligent metering system (iMSys) and a technical device to control the system. Until this technology is installed, the feed-in capacity is limited to 60 percent of the rated power for systems of seven kWp or more. For smaller systems, the limit of 60 percent remains permanent, even after installing an intelligent metering system.
Alleviating Grid Stress
Even with an intelligent metering system, new systems of two kWp or more will not receive feed-in remuneration if the wholesale electricity price is negative. This occurs when too much solar power is produced and there are no buyers at the electricity exchange. This happened for approximately 500 hours out of approximately 1,600 sunny hours last year. The lost compensation will be repaid with a 20-year delay.
This regulation encourages PV system owners to consume or store electricity themselves and feed it back in later, after sunset, during off-peak hours.
Industry Critique
The German Solar Energy Association (SFV) has voiced criticism against the new regulations. Professor Dr. Frank Hergert, a professor of regenerative energy technology at the University of Koblenz and a member of the SFV's board, disputes the 60 percent feed-in limit without control technology, arguing it can result in significant energy losses. Hergert also contends that the limit applies even in the absence of grid overload, primarily responding to market signals rather than the local grid situation.
Hergert further emphasizes that operators of smaller PV systems without smart meter infrastructure will face economic disadvantages in the future. While self-consumption and battery storage can offset losses, these investments may not be economically feasible or practical for all households. The SFV believes the new law poses a risk to the decentralized expansion of solar energy, serving as a cornerstone of the energy transition.
Opening Up Opportunities
Some industry companies see advantages for consumers in the newly regulated remuneration. Oliver Koch, CEO of Sonnen, an Allgäu-based company that manufactures intelligent storage systems, for instance, asserts: "The new law rewards the right time to feed electricity into the grid, not just the amount. For households, this means: Intelligent energy management and a storage system are now an absolute necessity, as those who don't have one will lose money."
Calculations by the company suggest that the abolition of remuneration through negative prices is more painful, bringing about a 25 percent decrease in income, than the feed-in cap, which reduces income by about 8 percent, according to the SFV. According to Koch, this can be offset through intelligent "direct marketing" of surplus PV electricity, which can be sold when prices are optimal, rather than when they drop into the negative. This is coupled with predictive charging of the storage system, based on factors like weather forecasts, ensuring the storage system does not begin charging in the morning but only when the 60 percent threshold is exceeded.
The installation of a smart meter is a prerequisite for direct marketing. However, Germany lags behind most European countries with a share of merely two percent in this regard. The increasing public pressure may potentially strengthen the implementation of smart meters, bolstering the new law.
Practical Tips for PV System Owners
PV system owners should, if possible, have an intelligent metering system (iMSys) with a controllable device installed or applied for if their system is installed after the deadline of February 25, 2025. This will help circumvent the limitation of the feed-in power and secure remuneration during peak solar yield. Although this results in additional costs for PV system owners, a smart meter protects against permanent yield losses and creates flexibility for later direct marketing or smart consumption control.
A battery storage system can help increase self-consumption and reduce yield losses due to feed-in limitations. If intelligent and based on predictions, it can largely offset the 60 percent rule. Households are best advised by installers on whether investing in a storage system is economically viable for them.
Systems with a peak power of up to seven kW are currently not affected by the obligation for control technology, but they are impacted by the abolition of feed-in remuneration during times of negative market prices. They are also reduced to 60 percent of their feed-in power and cannot surpass this, even after installing an intelligent metering system.
PV system owners can optimize their energy use and storage strategies in response to the Solar Peak Law to minimize its impact and take advantage of the new opportunities it presents. In the end, the law is unlikely to have as detrimental an impact as many market observers currently envision - provided that PV system owners take advantage of the new opportunities offered by the law to offset the restrictions. In fact, the law could even provide new saving or income opportunities, as flexibility becomes increasingly valuable, even for households.
- Understanding the changing landscape of renewable energy, it is crucial for Photovoltaic System (PV) owners to consider adopting an intelligent metering system and control technology to maximize their feed-in power and avoid the 60 percent limitation imposed by the Solar Peak Law.
- Industry experts suggest that while smaller systems with a peak power of up to seven kW are less affected by the Solar Peak Law, the installation of a smart meter and possibly a battery storage system can help increase self-consumption and offset limitations and losses.
- As the Solar Peak Law encourages PV system owners to consume or store electricity and feed it back in later during off-peak hours, it could potentially open up new opportunities for income generation through intelligent direct marketing and smart consumption strategies.
