What exactly is a solar water heater?
A solar water heater or solar system uses thermal solar collectors. This is different from the well-known PV panels that generate electricity from sunlight. A thermal solar collector transfers solar heat to water. The collector contains liquid whose temperature can rise to 90°C in the sun. This heat is transferred to the water in a storage tank via a heat exchanger.
Direct and indirect solar systems
Indirect solar systems consist of a storage tank that is connected to the existing water heater, boiler or combination of the two. Hence the name ‘indirect solar system’. In winter, when the sun shines less, the electrical or gas-fired water heater provides additional heating so that the comfort level is maintained and so that the entire solar system can always reach temperatures of 60° or more to prevent Legionella and other bacteria formation.
Our direct solar systems consist of solar water heaters integrated with a gas-fired boiler in one system solution. Here too, the water is preheated because the sun’s heat is delivered to the water via the heat exchanger. If this temperature is not sufficient, the integrated condensing HR water heater switches on as a reheater. Gas consumption is therefore kept to a minimum, making the installation very energy efficient. The advantage of reheating with gas or electricity is that higher temperatures can be achieved at any time. In addition, these products have an intelligent control with which weekly programs (including Legionella protection) can be set.
What is the payback period of a solar system?
The payback period depends on many factors. The intelligent control makes it possible to program the solar system based on individual usage requirements and tapping needs. In addition, the pump speed can be modulated to make optimal use of the available solar energy under all circumstances. Even with very little solar radiation, the efficiency remains maximum. With the SGS solar water heater, the extra solar contribution can amount to an average of 40% compared to a standard solar system.