Can you imagine that a window could produce free energy? It’s a vision which has been brought to life in the first positive-energy mixed-use apartment building in Europe: Hikari.

Hikari means “light” in Japanese and when you enter an apartment in this residential block in Lyon, you understand why it’s been given this name. Everything is designed to let natural daylight filter into the living space to improve the mood and lift the spirit. Even more, the pioneering eco-friendly building generates more energy than it consumes.

How has it achieved such exemplary environmental performance? The energy used in its apartments, shops and offices is generated partly by SunEwat XL BIPV (Building Integrated Photovoltaics) glazing. Huge glass panes with embedded photovoltaic cells do the same job as the solar panels often seen on roofs, except they’re part of the very fabric of the building.

To keep the environment at a comfortable temperature, the glass incorporates opaque photovoltaic cells which greatly reduces heat transmission, while still creating energy.

Other sources of renewable energy for the building include a geothermal energy system, as well as a cogeneration power plant fueled by locally produced rapeseed oil. The project stands as a shining beacon to what is possible in sustainable building today.

The Hikari building produces the equivalent of the consumption of approximately 160 homes.

Architect: Kengo Kuma & Associates
Location: Lyon, France