Increase the self-consumption of your solar panels from 30 to 80%: how to do it? "All the energy is directly injected into the boiler.
Unfortunately, anyone injecting solar energy into the grid only recovers a fraction of their investment. But before investing in a home battery, there is a more economical solution already present in your home: your boiler. By intelligently managing hot water production, you transform a simple appliance into a thermal battery that effortlessly boosts your self-consumption to 80%.
Self-consumption limit reached?
According to the latest figures from VEKA, Flanders has 1,071,810 solar panel installations. This represents a considerable amount of solar energy available for self-consumption. However, more and more households are reaching the limits of their electrical self-consumption. Of course, it is possible to run the washing machine or dishwasher during the day, but this consumption remains relatively low. The most significant consumption in a household is related to the production of domestic hot water and gas or oil heating .
Recovering excess solar energy
This is precisely the principle that Soliseco and my-PV rely on. These two companies offer affordable solutions to increase your self-consumption. They achieve this by capturing the surplus electricity produced by your solar panels to make hot water. Émilien Feron from Soliseco explains: "Instead of injecting your solar energy into the grid at an exorbitant cost, you use it to heat water. This way, you replace fossil fuels with free, self-produced energy. You immediately become less dependent on geopolitical uncertainties and fluctuations in energy prices."
How does a thermal battery actually work?
The technology is surprisingly simple: an intelligent control system measures your surplus energy using a digital meter and sends it to an electric resistance located in your storage tank. "A home battery of 10 to 15 kWh quickly costs several thousand euros," explains Roel Defrancq from my-PV. "A water tank acts as a thermal battery, a system you often already have at home. Whether you heat with oil , gas , pellets or with a heat pump, it works in all cases. For those who already have a battery, it is the ideal complement. The battery is often full by 11 a.m. The rest of the day, you can store this energy in your water tank."
Self-consumption up to 80%
Without a tracking system, the self-consumption of an average family is around 30%. With a home battery, it rises to 50-55%. Thanks to thermal storage, it reaches 70 to 80%, with or without a battery. Feron states: "We even see some clients with self-consumption rates of 85 to 90% in February and March. All the energy produced by the roof is directly injected into the boiler." Investing in solar panels thus takes on a whole new dimension.
Calculate your savings.
Are you wondering how much you can save by optimizing your self-consumption with solar panels or a (thermal) battery? Since every home and roof is unique, it is advisable to request several quotes for solar panels and home batteries and compare them.
No need for gas or oil for eight months of the year
According to experts, throughout the year, this method allows you to easily do without gas or oil for the production of domestic hot water for about eight months. "This represents a reduction of nearly 50% of your consumption," explains Feron. For the rest of the year, a hybrid system can be used. "On sunny days, the instant water heater heats the water to 65 °C, for example. If the temperature drops below 45 °C, the conventional boiler takes over. This way, you enjoy optimal comfort while minimizing your fossil fuel consumption."
two-year payback period
One of the main advantages is its ease of access. Generally, no major demolition work is necessary and, above all, the cost is affordable. Defrancq: "If you already have a boiler, you're set for about 1,500 euros, installation included. By using this system to reduce your consumption of heating oil, pellets, or gas for six months of the year, you will recoup the investment in less than two years." Feron: "With us, the complete solution, installation included, costs about 1,000 to 3,000 euros, depending on the complexity. Compared to an electric battery, thermal storage is two to five times cheaper per kWh of installed capacity."
Tips from the Livios editorial team:
One home battery easily costs between 5,000 and 10,000 euros. In contrast, an intelligent control system for your electric boiler is often available from just 1,000 euros. Therefore, for an average family equipped with solar panels, the return on investment for this "water battery" is much faster than that of a traditional battery.
Compatible with all heating boilers
Moreover, the system is compatible with almost all boilers, from old oil installations to modern gas condensing boilers. Defrancq explains: "my-PV solutions are limitless. They easily integrate into almost all existing installations, with or without a battery and with or without a digital meter. They are also compatible with energy management systemsand even home automation. Furthermore, dynamic pricing. my-PV products make it possible to convert a fossil fuel heating system into sustainable energy, even without solar panels.
Heat pump and electric resistance
Even if you have a heat pump, an electric resistance heater can be useful. "A heat pump is more efficient, but its compressor does not like constant starts and stops due to variations in brightness," explains Defrancq. "An electric resistance heater, on the other hand, handles these small temperature variations without any problem."
Smart priorities
People with a charging station or a home battery do not have to worry about interference between systems. The controls are smart and generally operate last. "The Soliseco box monitors the surplus energy on the digital meter," explains Feron. "When you come home and plug in your car, the surplus disappears and the water heating stops immediately. The car or battery takes priority, and the hot water completes the rest."
Conclusion
Thermal storage is primarily a no-brainer for:
Families with a digital meter who want to minimize their injections.
Households using gas, oil, or pellets who want to get rid of their expensive fuel that requires significant maintenance during the summer.
People with a large photovoltaic installation who still have energy left after charging a battery.
"This is an affordable intermediate step in the energy transition," concludes Defrancq. "Not everyone can shell out 20,000 euros tomorrow for a complete renovation with a heat pump, but for 1,500 euros, one can already significantly reduce their fossil fuel consumption."