For many households, hot water preparation represents a significant burden on the household budget. In particular, the use of an electric instantaneous water heater is one of the most expensive methods of providing hot water. A four-person household can quickly record an annual electricity consumption of around 1,600 kWh for hot water alone. At an electricity price of €0.32 per kWh, the costs add up to a whopping €512 per year - a considerable amount, but one that can be significantly reduced.
There is an efficient solution to reduce these electricity costs: the combination of a fothermo solar boiler with an electric instantaneous water heater. The solar boiler is connected in front of the instantaneous water heater and preheats the water using photovoltaic power. The preheated water then flows into the instantaneous water heater, which in the best case scenario does not even need to be activated because the water has already reached the desired temperature. In such cases, the hot water is provided exclusively by the solar boiler.
The 30-liter or 80-liter off-grid solar boiler from Fothermo is particularly suitable for this application. These solar boilers can be easily connected to 2-3 photovoltaic modules, which are connected directly to the boiler via an extension cable. The solar boiler uses the direct current from the photovoltaic modules directly and efficiently converts it into hot water. The heating process starts immediately.
The fothermo solar boiler reaches a maximum water temperature of 65 °C. Since the ideal shower temperature is around 34 °C, the desired temperature can be easily set using the mixing valve on the shower. This flexibility ensures comfort and safety in everyday life.
By using a solar boiler, the electricity consumption of an electric instantaneous water heater can be reduced by around 75%. This corresponds to annual savings of €300 to €400. With these savings, the investment costs for the solar boiler are paid off within just 2 to 4 years. After that, you can enjoy hot water almost free of charge - a convincing argument from both a financial and an ecological point of view.
Another great advantage of the fothermo solar boiler is its easy installation, which can also be carried out by laypeople. The photovoltaic modules are connected easily using plug-and-play, and the solar boiler is just as easy to install as a conventional electric boiler. Since the entire system uses the direct current from the photovoltaic modules directly, it is an island system that does not need to be registered. This saves you additional bureaucratic effort.
Optionally, excess electricity that is not needed to heat water can be fed into your own home network via a balcony power plant inverter using the fothermo switching device. This way, every ray of sunshine is used optimally and you maximize the benefit of your photovoltaic system.
The combination of a fothermo solar boiler with an electric instantaneous water heater offers an effective way to drastically reduce the high costs of hot water preparation. Thanks to the simple installation and the bureaucracy-free use, this solution is not only economical, but also practical and sustainable. Use the power of the sun and enjoy cheap, environmentally friendly hot water in the long term!
The team at fothermo System AG is available at any time for further information or individual advice. Let us find your hot water solution of the future together!
