The young Swiss company, DHP Technology, develops and builds the worldwide unique solar folding roof HORIZON. This allows infrastructure areas that are already in use, such as sewage treatment plants, car parks, logistics areas and other sealed surfaces, to also be used for solar power production. And this without restricting the primary use. It is one of only a few Swiss projects to have received support from the European Union’s Horizon 2020 funding program and has already received several awards.

DHP employs around 30 people at its own production site in Zizers/Graubünden in Switzerland.

Interview with Gian Andri Diem, Co-Founder & Managing Partner at DHP Technology.

Easy Engineering: What are the main areas of activity of the company?

Gian Andri Diem: One of the main areas of application of the solar folding roof is above sewage treatment plants, i.e. directly above open clarification tanks. Conventional, fixed solar systems cannot tap into these areas, as they hinder the operational business.

The solar folding roof is developed as a lightweight construction. This makes it possible to build with few slender supports and great heights (> 5m) above ground. The folding of the modular sheets prevents the impact of forces caused by storms, hail and heavy snowfall. For maintenance work on the tanks, e.g. with a crane, the solar folding roof can be retracted manually at any time. An additional benefit is the shading of the tanks, which reduces algae growth and thus maintenance. Furthermore, a meteo algorithm automatically retracts the solar folding roof when adverse weather conditions are imminent. In case of snowfall this protects the modules and keeps them free of snow. This enables solar power to be produced in snowy regions even in winter.

Our second focus is on sealed surfaces such as car parks, logistics areas or motorway service areas. The first car park project at the valley station of a mountain railway was realized in 2020. The topic of agri-photovoltaics might also become interesting: We are currently developing a pilot project for a vineyard.

E.E: At what stage is the market where you are currently active?

G.A.D: After the development and implementation of a pilot project in 2017/18, the product was ready for the market. Currently, 12 solar folding roof projects are in operation in Switzerland and another five will follow by the end of 2022. 

We receive enquiries from all over the world – from the US to Saudi Arabia and China. Currently, we are concentrating mainly on the European market. Just a few days ago, we received approval for the first project in Germany, which will go into operation in early 2023. Another 10 projects in Germany are in various stages of implementation.

E.E: What can you tell us about market trends?

G.A.D: The demand for electricity has risen again recently – in industry, which is now building up capacity again after the first Corona setback, but also among private individuals who are spending more time at home. Higher demand with the same supply means, quite fundamentally, rising prices. This is also the case with electricity. The political situation in Ukraine is dynamite for further price jumps. In addition, the last nuclear power plants and more hard coal-fired power plants will be shut down in Germany at the end of the year. However, higher electricity prices also have their good side, because they can be an incentive to take energy-efficient measures.

Energy self-sufficiency thanks to local electricity production: In order to become independent of the electricity market, more and more companies want to invest in a decentralized supply of their own electricity. This is particularly true for sewage treatment plants, as they are among the largest energy consumers in a community. Since sewage treatment is financed through fees, they want to ensure that these fees remain affordable in the future by increasing their own electricity production from renewable sources.