Meriaura Energy provides near-carbon-free heat with the support of cold-formed open sections from SSAB

In the town of Bad Rappenau, just north of Stuttgart, a remarkable energy revolution is quietly unfolding. Spanning 29,000 square meters – the size of ten football fields – Germany's largest flat plate solar collector plant is now powering a district heating network that provides near-carbon-free heat to 22,000 local households.

“The nominal power of the solar thermal plant is approximately 20 MW, which makes it one of the largest of its kind in Germany. It supplies carbon-free heat to everything from single-family homes and apartment buildings to hospitals, hotels, and spa complexes in Bad Rappenau,” says Antti Lilleberg, Managing Director of Meriaura Energy.

Built by the Finnish company Meriaura Energy Oy for Bauer Holzenergie GmbH, the system integrates 1,800 highly efficient Savo 16S solar collectors with an 8,000 m³ heat storage tank, significantly reducing the space needed to generate clean energy.

Cost-efficient precision parts with SSAB

Meriaura Energy Oy was founded in Mikkeli, Finland in 2009, where it maintains its production. Today, it offers some of the world’s most efficient solar collectors, which minimize the need for land area for solar energy generation.

The company has been an SSAB customer since 2015, who first began delivering cold-formed steel sections to Savosolar, which later merged with Meriaura Group and became Meriaura Energy in 2023.

“In the past we did the forming of the frame components ourselves. But with the collaboration with SSAB we can have a more cost efficient way to get precision parts for our products,” says Antti Lilleberg.

Specially tailored C- and U-sections

Meriaura Energy uses tailored metal coated steel sections made of SSAB Galfan coated steels DX51D+ZA300-A for the solar collectors, as well as C-sections of SSAB Domex 350GD for glazing support and SSAB Domex 355MCD with hot dip galvanizing to poles. In addition, SSAB supplies SSAB Galfan coated steel for the back sheets of the solar collectors, ensuring both durability and sustainability.

“We choose SSAB mainly for two reasons. First, from our point of view they are a local company supplying steel for us in Finland. And secondly, for their very high quality, for we work in very demanding conditions such as hot, cold, humid and very arid or corrosive environments. The plant has to last at least 25 years, so we place very high requirements on the quality of the materials we source,” says Antti Lilleberg.

Increased demand creates new needs

As Meriaura Energy has grown as a company, its needs have also changed, says Tiina Paajanen, Account manager at SSAB. Previously they bended the profiles themselves. Today, as volumes increased, they wanted to find a more cost-effective solution delivered by SSAB.

“The shape of the section isn't easy to bend, but roll-forming offers them more possibilities and ensures consistent quality from batch to batch, with tight tolerances. SSAB can deliver fixed lengths with punching directly from the production line to Meriaura Energy – essentially providing pre-fabricated, custom components for quick assembly. These sections are also easy to transport and install,” says Tiina Paajanen.

Antti Lilleberg is very pleased with how the collaboration with SSAB has worked over the past ten years.

“SSAB has been excellent in product quality as well as being responsive to our needs and being flexible as a supplier.”