Solar tiles for new and historic buildings

Swiss start-up Freesuns has developed solar tiles for building-integrated PV it claims can be used on historic as well as new buildings.

Freesuns chief executive John Morello said the tiles can be sized to completely replace conventional roof tiles in fiber-reinforced concrete, with all three models able to potentially cover 100% of a roof surface, including on complex roof layouts.

Every tile hosts an electrical safety circuit to help prevent fire-risk, the company said, adding the product is ultra-resistant as it is manufactured with double tempered glass.

Standard

Standard solution the Solaris Classic is a 525mm by 460mm tile which reportedly delivers 154 W per square meter. It costs CHF292 (€276), excluding VAT and Morello told pv magazine, “This value is just an indicative value as the price can change depending on the complexity of the project.” The tile – glossy black with silver lines – is said to be ideal for new-build or renovated structures as it offers a modern architecture style.

The Solaris Classic has been deployed on a 211m² residential roof in Colombier, Switzerland, amounting to 28 kW of solar generation capacity and added 32 kW on a 240m² residential roof in the municipality of Pully. Freesuns said another, 160m² residential roof in Genolier boasted capacity of 24 kW.

Black

The Premium Black model is a 420mm by 400mm product with a slightly lower output of 136 W per square meter at a price of around CHF304/m². The model is recommended for modern architecture and for the replacement of cement tile roofs.

Heritage

The Heritage product is the most expensive, at around CHF308/m² and reportedly offers power output of 128 kW/m² from the same dimensions as the Premium Black product, although Morello said all three versions are available in smaller formats to ensure complete roof coverage as an option.

The matt gray Heritage tile has no visible lines and could be used to replace slate-style roofs on historic buildings, according to its developer.

The tiles were installed on the 18th century Grand Chalet of Rossinière, one of the oldest chalets in Switzerland.

“For such an important heritage property it was critical to preserve the historical context in the appearance of the roof so it remained sympathetic to the site,” Freesuns said. “It was also a challenge to convince the local authorities charged with protecting the heritage of the Grand Chalet to allow solar on the roof of this building.”

The roof of the historic building now hosts 8 kW of PV capacity across 54/m². The Heritage tile is also being used on a 168 kW project under development on a 1,200m² roofspace at another historic building in Switzerland.

Freesuns said the tiles come with a warranty which guarantees they will maintain 90% of power output after 10 years and more than 80% after 20 years.