Germany's Largest Solar Thermal Plant Now in Operation

Germany’s largest solar thermal plant by far has officially gone into operation in Leipzig. With this solar cogeneration plant, the municipal utility of the “City of Trade Fairs” aims to feed carbon-dioxide-free heat directly into the district heating network in the future. The project aims to demonstrate the role solar thermal energy can play in municipal heating networks in the future.

The new, massive plant in the Lausen district is intended to make Leipzig’s district heating greener. To date, district heating across Germany has been generated almost exclusively from natural gas. That is set to change, with fossil fuels increasingly being replaced by renewable energy sources. In Leipzig, the goal is to provide residents with “climate-neutral” district heating by 2038. The plant was originally scheduled to go into operation in May of this year.

How the heat is generated

The plant is expected to supply 2 percent of Leipzig’s annual district heating demand. Its construction cost around 40 million euros. 

13,200 collectors with a total gross collector area of 65,208 square meters were installed by the company Ritter Solar. The collectors are long, black-and-blue, double-walled glass tubes embedded in parabolic mirrors. Inside them run water-filled pipes that resemble an immersion heater. When the sun shines on the collectors, the water inside becomes boiling hot. Heat is generated.

Approximately 60 ground-mounted solar thermal systems are in operation nationwide

“The Leipzig project shows that renewable heat can already be used today on a power plant scale to supply cities,” said Carsten Körnig, CEO of the German Solar Industry Association (BSW-Solar). According to the association, there are currently around 60 ground-mounted solar thermal plants in operation nationwide. 

In a report on “Prospects for District Heating,” the VKU association assumes that large-scale solar thermal plants can be a valuable addition to the heat mix under suitable local conditions. By 2045, approximately two percent of district heating across Germany could be generated using solar thermal energy.