Increase the output of your PV system with repowering

More and more companies and private households are turning to photovoltaics on their own roofs. In 2023, over one million new systems with a total output of around 14.6 gigawatts peak were installed in Germany. 69% of the installed PV output comes from rooftops. This is also because the modules installed are constantly evolving and generating more power on the same surface area. High self-consumption saves costs and at the same time contributes to the company's climate goals. But what happens when the available roof area is running out, the solar system is getting old, or the company wants to benefit from advances in solar technology? Solar repowering can help! The old photovoltaic modules are simply replaced with the latest solar technology. All with less effort and in less time than when installing a new system. 

In this article, we present the repowering of rooftop PV systems and tell you more about the benefits of solar module replacement for your company. In addition to the remuneration and implementation of your modernized system, we also discuss some regulatory changes. The Solar Package 1 passed by the German parliament in April makes the repowering of rooftop PV systems more attractive than ever before. And you don't have to worry about your old modules either. We tell you what you need to know about recycling. 

But what exactly is repowering? In German, it means nothing more than "power plant renewal" and is primarily known from wind power. It describes the replacement of older (wind power) plants or solar modules with newer and more efficient parts. Solar repowering uses the same principle to replace old solar modules with more powerful, more efficient and more profitable modules. The old modules are removed and new ones are installed. 

Until now, however, this was only possible to a limited extent, as operators could not be remunerated for the additional power generated via the EEG subsidy. Solar Package 1, which was adopted in April 2024, has now changed this: From now on, solar modules can be replaced regardless of their condition and operators will continue to benefit from EEG remuneration. 

Before the solar package was adopted in spring 2024, repowering rooftop photovoltaic systems was not worthwhile in many cases. This was because only damaged, faulty or stolen modules could simply be replaced. Otherwise, solar operators were at risk of losing their subsidies under the Renewable Energy Sources Act (EEG).  

With Solar Package 1, system operators can now also claim the EEG remuneration entitlement for the old modules with new modules. The additional output generated by the modernized solar modules is remunerated with the EEG subsidy applicable at the time of commissioning. The additional output is considered a new installation and is entitled to remuneration for 20 calendar years.  

Companies that have so far only covered their own electricity consumption on a pro rata basis will benefit in particular. This is because the higher the proportion covered by self-generated electricity, the greater the cost savings. 

Solar modules are becoming ever cheaper and more powerful. While the module price was still 50 cents per watt peak in 2016, solar modules will only cost around 13 cents per watt peak in 2024. This corresponds to a price reduction of around 75 percent in just eight years. A trend that is likely to continue in the future, fueled by technological advances and high production capacities overseas.  

Under optimal conditions, modules can now generate 210 watts per square meter. A company roof area of 1,000 square meters can therefore accommodate up to 210 kilowatt peak total output. Just 10 years ago, a mere 170 kilowatt peak was possible on the same area. An increase of a whopping 23.5 percent! 

Additional potential can usually be realized much faster through repowering than by building a new system. How much faster depends on the age of the existing system and the reserves of the electrical system. This is because the technology, such as the inverters and cables, must be able to handle the additional power. If this is not possible, you have to retrofit and modernize. In addition, a grid inquiry must be carried out to ensure that the existing grid infrastructure can cope with the additional power. In any case, companies avoid additional structural analysis or civil engineering measurements. This saves money. 

And what happens to the old modules afterwards? The components of your old solar modules are almost completely recyclable. According to an EU directive, PV module manufacturers are even responsible for recycling. As a company, recycling the solar system therefore costs you nothing. The manufacturers are also responsible for this.  

A private initiative is now even making it possible to donate old solar modules to Ukraine. And the energy payback time of the modules is also no cause for concern. According to Fraunhofer ISE, the time it takes for the energy consumed during production to be generated again ("energy payback time") is just six months to one and a half years. 

Repowering costs your company far less money and time than building a new system. The module replacement itself only takes a few days and is also far cheaper than building a new system. The installed inverters and cables may also need to be replaced to support the additional output. As the roof infrastructure for the solar system is already in place, no additional renovation or civil engineering work is required. Depending on the age of the system and the additional output generated, the necessary grid inquiry may also be shorter. In any case, solar repowering reduces the planning costs for project planners.  

In addition, roof renovations can be planned more efficiently. These do not necessarily have to coincide with the initial installation of the PV system, but can also be tackled at a later point in time – for example when repowering. As a result, the initial investment is lower in some cases, which increases the attractiveness of a PV system for many companies. 

Achieving your climate targets is easier than ever. A modern and powerful solar system combined with an efficient electricity storage system can reliably supply your company with green electricity. Repowering allows you to produce more electricity by installing more powerful solar modules on the same roof area. This allows you to save even more costs or generate additional income in no time. Sola package 1 enables you to benefit from constant technological progress and module prices at record levels. 

ENVIRIA makes the energy transition radically simple for companies. We are happy to help you upgrade your PV system so that you can continue to get the most out of your company roofs in the future and benefit from the latest solar technology. As a 360-degree provider, we take care of all the planning, procurement, implementation and maintenance details for you. Have we piqued your interest? Then we look forward to hearing from you. Our experts will be happy to help you with any questions you may have about repowering your PV roof system.