Glass roof tiles that heat your home

A Swedish company called SolTech Energy seems to have cracked this challenge. It uses a simple but eye catching solution that provides many configurations: glass tiles.

Instead of traditional roof tiles made of concrete or clay, SolTech use tiles made of glass, allowing the sun to shine through onto the absorbing surface underneath. The energy generated is integrated with the building’s existing heating system or electrical grid.

The system works in a few versions. The first is the simple one supporting heat carried by air. Unlike competitors’ versions, the system doesn’t heat up water or vacuum pipes, but clean air. The tiles are installed on top of a black nylon canvas, under which air slots are mounted. The black color absorbs heat from the sun and the air starts to circulate. The hot air is then used to heat up water, which is connected to the house’s heating system via an accumulator. The beauty of the system is that it cuts energy costs throughout the year, during dark winter days as well as night time, due to its capacity to store heat in the isolating layers of air under the canvas.

The second version of the system does the exact same thing but with water circulating under the glass tiles. It makes a lot of sense to use big areas of the roof to heat water. After all, a common house roof is subjected to about five times more energy each year, from the sun, than the house’s total energy consumption. The system is designed to be integrated with the house’s existing energy solution, both air-based and water-based, such as a ground source heat pump, air heat pump, pellet boiler, oil boiler or electric boiler. The most common solution is that the system is connected to a water-based heating system via an accumulation tank, but it also offers other solutions. The only requirement is that the house has some form of central heating systems.

The third version really hits solar panels in the soft part of the stomach. It contains a whole solar voltaic system under the icy glass look instead of the ugly square panels. As the company describes:

“We replace the traditional roof tile with our glass roof tiles and underneath these solar cells are placed to generate electricity. We use high efficient, market leading CdTe thin film solar panels especially developed for SolTech Energy and SolTech System. We place the solar panels between the carrying battens, underneath the roof tiles, where they are protected from damage and theft.”

“By using CdTe thin film solar cells we will achieve higher efficiency as temperature rises compared to traditional silicon solar cells. CdTe thin film solar cells are also more efficient in diffused light. These factors combined, we estimate, will result in 5-10 percent more kWh produced per installed W”.