Solar power across walls and roofs: The future of commercial buildings

“The old-fashioned way of thinking is that solar cells are large panels placed on top of roofs. But today, the possibilities are almost endless for integrating solar power into a building. If you plan for solar power from day one, you can construct an active solar cell surface without much additional cost,” says Trine Berentsen, CEO of the Norwegian Solar Energy Cluster.

From solar-powered data centres to glass exteriors that produce electricity: this is how green commercial buildings in Norway are built with solar cells.

Award-winning energy-plus houses

How do you construct a house that produces more energy than it consumes? You can cover the entire building with solar cells – like Solcellespesialisten did for Powerhouse Brattørkaia. This summer, Powerhouse Brattørkaia won an award for “Outstanding project” at the international Intersolar Smarter E Awards.

“Almost the entire building, both roofs and walls, produce energy,” explains Carl Christin Strømberg, CEO of Solcellespesialisten.

That is largely due to smart use of building-integrated photovoltaics (BIPV) – that is, solar cells that are not attached to the exterior of a building, but instead form part of the building material itself. BIPV is a difficult technology to implement, something Solcellespesialisten experienced during the Powerhouse projects.

“The whole building had a sky-high ambitions level. The architects wanted, for instance, the solar cells not to have frames and not to be attached with screws. Because each part weighs almost a hundred kilos, we had to be particularly innovative with using glue. No one had done this exact thing before with solar cells,” says Strømberg.

Solcellespesialisten has been one of the fastest growing solar power companies in Norway: from revenues around USD 200 000 in 2014 and aiming for over USD 20 million in 2020. Now, the company is establishing a factory in Elverum in Eastern Norway, where it will produce its own building-integrated photovoltaics.

“We have, so far, based our production on international subcontractors. But that makes waiting times longer. Also, we don’t always get the quality we need,” Strømberg explains.

He believes that building-integrated photovoltaics eventually will become the norm for new buildings.

“We have reached a point where BIPV represent only a minor increase in cost – compared to certain exclusive glass exteriors, it’s even at the same price level. That means it is becoming a profitable investment, as well as an environmentally sound one,” he says.

“For building-integrated photovoltaics, Norway is taking a leading role in Europe, thanks in good part to a domestic construction industry which has had the means and will to try new solutions.”

“Blue roofs” and data centres

“The private sector is beginning to realise that solar power offers a competitive advantage and a sustainable profile, on top of the savings in electricity. We find that it’s the consumers, and our customers’ customers, that have high demands and expect solar powers,” says Per Urdahl, CEO of Energima Solel, a Norwegian provider of all-inclusive solar power solutions.

Energima Solel is part of the Energima group, which has completed solar installations on more than 130 office buildings, schools, warehouses, shops, and more.

The company’s latest achievement is Norway’s first solar installation on a “blue roof” – that is, a roof designed for gathering and gradually draining rainwater. The roof prevents overload on drainage and plumbing systems. It becomes, in practice, a temporary water reservoir when it rains.

“This was a whole new challenge. It is not easy to install solar cells that function safely above a water reservoir on a roof, while being resistant to wind and bad weather. The installation was a milestone for us as a company, and these solutions will probably become attractive in other cities and countries going forward,” says Urdahl.

Energima Solel has also constructed Norway’s first solar installation for a data centre.

“We’re very pleased with our data centre project. It has been operational for a few weeks now, and it is meeting expectations. Many data centres say they are green because they buy wind or hydropower capacity, but here the power supply is local and on the roof above the data centres,” Urdahl explains.

Football stadiums and public buildings

FUSen is another Norwegian company that builds, delivers, and installs bespoke solar cell solutions for commercial buildings.

“We start with the customer’s needs, either for roofs or facades. We design the best installation from the best components – and then deliver the project with all-encompassing construction,” says Thor Christian Tuv, founder and CEO of FUSen.

Since being founded in 2012, the company has equipped Norwegian offices, warehouses, shopping centres and even football stadiums with solar power. FUSen also offers solutions for smart control, helping customers to get the most out of electricity when it is produced.

The company’s latest flagship installation is the exterior of the Norwegian Petroleum Directorate in Stavanger in Western Norway. Here, solar cells are integrated in the glass facade.

“To put it mildly, we’re pretty proud of this. I would say that we’ve created something that is both beautiful and environmentally sound. The architect was able to draw the building without special adaptations for solar cells, and we created a glass exterior filled with solar cells,” says Tuv.

He thinks that the bar for installing building-integrated photovoltaics is constantly being lowered.

“We in the solar industry has come so far that architects don’t have to limit their designs to incorporate solar panels. And the added costs of building-integration are much lower than what people think. Many people are also realising that it is a good and visible environmental initiative, which also improves a company’s brand,”

So far, FUSen has primarily provided solar installations in Norway, but the company is actively looking for opportunities abroad. Tuv believes that Norwegian solar companies have certain competitive advantages, especially for building-integrated photovoltaics.

“In Norway, many construction projects have been willing to allocate significant resources to new solar technology. This way, Norwegian solar companies have gained a lot of valuable experience, and many of them are far ahead on certain advanced solutions. I think many of those solutions are ready for an international market,” he concludes.

Solar cells ready for export

Berentsen at the solar energy cluster thinks the projects are important for making commercial buildings greener.

“These buildings have an incredibly important signalling effect – they show that advanced solar projects can also be aesthetically pleasing. The fact that some companies are pioneers is essential for driving the solar market forward,” she says.

Berentsen believes that Norwegian companies are well equipped to create green commercial buildings outside Norway.

“Solar cells for commercial buildings is an area where Norway has relatively large advantages: we have high competency in construction, wooden materials and energy systems. The companies also show that we are good at combining technologies and making them work. That is good for exports,” she concludes.