Scroll to Top
Right Arrow

Solar thermal

Solar thermal energy converts sunlight into heat — ideal for hot water production and heating support in residential buildings, industry and agriculture.

Solar thermal

Solar thermal energy is a technology that converts solar radiation into usable heat. Unlike photovoltaics, which generate electricity, solar thermal systems are used to produce heat for water heating or to support heating systems in buildings, industry, or agriculture.

How it works

Solar collectors — usually installed on rooftops — absorb solar radiation and transfer the heat to a heat transfer fluid (typically water with antifreeze).

This heated fluid flows through a heat exchanger, where the energy is transferred to a storage tank or heating system.

The stored heat can then be used for hot water supply, space heating, or low-temperature industrial processes.

Unlike photovoltaic systems, solar thermal installations do not require inverters or battery storage systems. Instead, they rely on thermal storage systems, such as buffer tanks or hot water storage tanks.

Typical applications

• Domestic hot water production in residential and multi-family buildings
• Heating support systems (e.g. combined with gas boilers or heat pumps)
• Process heat in industry and agriculture (e.g. laundries or food production)
• Solar-supported district heating systems
• Combination with PV systems for optimal use of available roof space

Key figures

Collector area (m²): determines the heat generation capacity
Efficiency: typically 50–70% conversion of solar radiation into heat
Annual heat yield (kWh/m²): depends on collector type and location
Temperature level: typically suitable for applications up to approx. 90°C
Storage volume (liters): determines how long the heat can be stored and used

Summary

Solar thermal energy is an efficient technology for producing renewable heat — particularly in buildings, agriculture, and commercial applications with a continuous demand for hot water.

It complements photovoltaics well because both technologies use solar energy but produce different forms of energy. Together, they can contribute significantly to reducing fossil fuel consumption and CO₂ emissions.

Close Cookie Popup
Cookie Einstellungen
By clicking “Accept All”, you agree to storing cookies on your device to enhance site navigation, analyze site usage and assist in our marketing efforts as outlined in our privacy policy
Strictly Necessary (Always Active)
Cookies required to enable basic website functionality.
Cookies helping us understand how this website performs, how visitors interact with the site, and whether there may be technical issues.
Cookies used to deliver advertising that is more relevant to you and your interests.
Cookies allowing the website to remember choices you make (such as your user name, language, or the region you are in).