Sweden: Solar Panels and Home Batteries Face Tough Test – This Was Revealed About Profitability
The Swedish research institute Rise tested solar power and battery systems from three different suppliers in a laboratory, using the energy profiles of four hypothetical single-family homes. The payback periods for the systems ranged from 13 to 22 years, even when tax deductions were taken into account.
Many homeowners are considering not only solar panels but also the purchase of a home battery. The Swedish state-owned research institute Rise, commissioned by the Swedish Energy Agency (Energimyndigheten), investigated how cost-effective the use of home batteries and solar panels actually is.
The study, published in September 2026, compared the use of solar panel and battery systems from three different suppliers in four hypothetical Swedish single-family homes. The system suppliers were Ferroamp, Solis, and Huawei.
The homes were heated either with district heating or an air-source heat pump. They also had the option to charge an electric vehicle battery.
The results of the study were reported by the Swedish technology magazine Ny Teknik. According to the magazine, the aim of the test was to provide a more realistic picture of system performance and cost-effectiveness than what could be derived solely from figures measuring size or efficiency.
The suppliers were invited to propose systems suitable for the houses. Although all suppliers received the same data about the houses, the proposed systems differed in their sizing.
The research institute installed the suppliers' inverters and batteries in a laboratory. The systems were supplied with electricity in a manner that simulated the output of solar panels. In addition, a heat resistor simulated the electricity consumption of the houses. The tests were conducted over four days, intended to represent a full year of operation.
The system sizing affected the payback period
According to the study, the payback periods for combinations of solar panels and home batteries ranged from 13 to 22 years, taking into account the tax deduction for green technology currently in use in Sweden.
The shortest payback period of 13 years was achieved in a detached house with district heating that also had an electric vehicle. The system, sized for the house and provided by Ferroamp, featured a battery with a capacity of 14 kilowatt-hours and solar panels with a peak output of 7 kilowatts. During winter, the home battery was used to smooth out the consumption peaks caused by charging the electric vehicle, which reduced the power fee.
Conversely, the longest payback period of 22 years was observed in a detached house with district heating that did not have an electric vehicle. The system provided by Huawei was large relative to the house's electricity consumption: the battery had a capacity of 20.7 kilowatt-hours, and the solar panels had a peak output of 12 kilowatts.
The study suggests that in some cases, the payback period could have been shorter if only solar panels had been installed in the house.
"Our results show that batteries can increase self-consumption of solar power and improve the reliability of a home's electrical system. However, the study also shows that in most cases, the greatest economic benefit comes from the solar panel system itself," Patrik Ollas, a researcher at RISE, told Ny Teknik.
According to him, the technology has evolved since the project began in 2024. For example, AI-based control systems have become more widespread, and not all choices in the testing methodology still reflect current battery systems.
If new control services perform as promised, they could, according to him, achieve better economic results than those of the test.
The profitability of home batteries has also been studied in Finland. According to a study by the University of Turku and Turku University of Applied Sciences, published in May 2026, annual savings from home batteries typically amount to only a few tens or hundreds of euros, which is too little to cover an investment of thousands of euros.
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Frequently asked questions
What were the calculated payback periods for solar and battery systems in the Rise laboratory study?
The payback periods for the tested systems ranged from 13 to 22 years, even when Swedish tax deductions were included. This long timeframe indicates that the financial return on investment is significantly slower than many homeowners might expect.
Which specific supplier's system achieved the shortest 13-year payback period in the Rise study's four home scenarios?
The Ferroamp system achieved the shortest 13-year payback period in a detached house with district heating and an electric vehicle. This specific configuration featured a 14 kilowatt-hour battery capacity, representing the most favorable outcome among the tested scenarios.
Why does the Rise study suggest that home battery investments may not be cost-effective for typical Swedish households?
Annual savings from home batteries typically amount to only a few tens or hundreds of euros, which is insufficient to cover the initial investment. This disparity means that the financial benefits are too small to justify the high upfront costs for most residential users.