Researchers build concrete that stores solar power

A prototype for an ultra-thin, sinuous concrete roof using innovative design and fabrication methods has been designed and built by researchers from the ETH Zürich.

The tested novel formwork system will be used in an actual construction project for the first time next year.

Researchers led by Philippe Block, Professor of Architecture and Structures, and Arno Schlüter, Professor of Architecture and Building Systems, want to put the new lightweight construction to the test and combine it with intelligent and adaptive building systems.

The self-supporting, doubly curved shell roof has multiple layers: the heating and cooling coils and the insulation are installed over the inner concrete layer. A second, exterior layer of the concrete sandwich structure encloses the roof, onto which thin-film photovoltaic cells are installed.

Eventually, thanks to the technology and an adaptive solar façade, the residential unit is expected to generate more energy than it consumes.

The building technique for the roof was developed by the Block Research Group, led by Prof. Block and senior researcher Dr. Tom Van Mele, together with the architecture office supermanoeuvre, and tested out on a full-scale prototype.

“We’ve shown that it’s possible to build an exciting thin concrete shell structure using a lightweight, flexible formwork, thus demonstrating that complex concrete structures can be formed without wasting large amounts of material for their construction,” said Block.

“Because we developed the system and built the prototype step by step with our partners from industry, we now know that our approach will work at the NEST construction site.

The process to get to this point took almost four years, from the start of the project to the finished prototype, partly because Block wanted to involve several industry partners in development of the prototype. Next year, he plans to build the roof once again at the NEST building in eight to ten weeks.