Munich, 13 February 2024 – According to the German Solar Association (Bundesverband Solarwirtschaft), 2023 was the strongest year ever for photovoltaic (PV) system installations in Germany. Of the more than one million new systems, around 50 percent were installed in homes – signaling strong momentum for the energy transition in the country. However, homeowners with PV systems need more than just a solar rooftop system to get the most out of their self-generated electricity production. An expert from gridX explains what needs to be considered during a home upgrade to maximize self-consumption.
Self-sufficiency only with batteries
"Installing a solar system on your roof or balcony railing is definitely a good first step towards gaining more freedom in energy consumption at home and becoming more self-sufficient," says Baptiste Feron, Head of Energy Management at gridX, Europe's leading smart energy company. But that's the crux of the matter, according to the expert: "Just because you can produce your own electricity doesn't mean you're completely self-sufficient. That's a misconception," explains Feron. For a home to maximize its level of self-sufficiency, i.e. be largely independent of the electrical grid and able to power the household with locally-produced electricity, you need much more than just the generation source. According to the expert, many components are involved. "The linchpin is the ability to store energy or shift consumption," explains Feron. Without battery storage on site, energy can’t be stored to cover periods when no electricity is being produced. This would mean that PV power couldn’t be used at night, for example.
Reduce payback period for energy systems
According to Feron, it therefore certainly makes sense to combine a PV system with a battery storage system to maximize the self-sufficiency of a home. However, consumers often shy away from making the purchase for financial reasons – even though modern storage systems for a typical house are no longer as cost-intensive as they were a few years ago. "Typically, homes should plan for a storage capacity of between five and 15 kilowatt hours (kWh) – depending on their consumption, the installed PV capacity and the level of self-sufficiency they are aiming for," says the gridX expert. The cost of such systems would range between roughly 4,000 and 11,000 euros. However, according to Feron, these costs can usually be amortized within a few years – depending on the country and the local regulation –, as the combination of a storage and PV system can significantly reduce the amount of electricity drawn from the grid and thus minimize electricity costs.
Full efficiency of PV systems with energy management
The expert recommends an additional step to further increase self-sufficiency and recoup the initial investment even faster. "Anyone who connects their decentralized energy resources such as PV systems and batteries with a smart energy management system (EMS) can ensure that all energy flows – regardless of whether they are being consumed, stored or generated – are used optimally without any effort on their part," explains Feron. An EMS, such as the manufacturer-independent solution from gridX, holistically monitors all energy flows in a home and dynamically and automatically adjusts electricity demand in real time depending on factors such as renewable energy generation, grid restrictions, electricity prices or individual preferences. This maximizes self-consumption and reduces costs with minimal effort for end users. For example, storage devices like batteries or electric cars can automatically be charged when electricity prices are low. According to the gridX expert, the concept becomes even more attractive if other energy systems are also available: "Each additional shiftable asset like heat pumps, electric rods or heaters helps to optimize self-sufficiency and the benefits for consumers." An EMS is particularly suited to households with heat pumps, alongside those with a local PV system and a household battery. Surplus solar energy could also be stored as thermal energy to be used to heat the home later when the sun is no longer shining.
((Illustration: © gridX GmbH, Reprint free of charge; Image caption))
Integration is key: According to gridX expert Baptiste Feron, a PV system alone is not enough to make a house self-sufficient. The decisive factor is the combination of PV and battery together with a smart, manufacturer-independent energy management system.
gridX is Europe's leading smart energy company based in Aachen and Munich. With its IoT platform XENON, gridX enables manufacturer-independent monitoring and management of distributed energy resources. XENON allows partners to develop and scale energy management solutions faster than ever before. By partnering with gridX, Fastned is able to install more charging points at sites without the need for costly grid extensions, and the Viessmann Group is able to offer its customers intelligent and integrated home energy management systems.