Greenhouses that produce their own energy

Special solar cells generate electricity using the wavelengths of light not used in photosynthesis

Spotted: The Swiss federation of fruit and vegetable growers has set an ambitious goal of eliminating all fossil-fuel-based energy from its farming processes by 2040. This is no small feat, as growing vegetables in greenhouses requires a lot of power to maintain the optimal temperature and humidity for the plants. Now, a startup called Voltiris is developing solar modules that could make self-powered greenhouses a reality.

The company’s modules use photovoltaic cells to convert sunlight into electrical energy, which can then be used to power things like lights, fans, and pumps. The company’s solar modules are similar to those of conventional solar panels but with a twist: they only utilise around half the light. Plants use only a portion of the spectrum of visible light for photosynthesis. The company’s key insight is that the remaining wavelengths can be used to generate solar power.

The Voltiris system uses filters that allow red and blue light to pass through and reach the leaves of the plants below. Meanwhile, the green and near-infrared wavelengths are directed towards photovoltaic cells that generate electricity. While the company is still piloting the technology, it has recently harvested the first vegetables grown using its system from two greenhouses in Valais and Graubünden.

Results from the pilot study showed the system is able to half a greenhouse’s carbon dioxide emissions while simultaneously providing between 60 and 100 per cent of its energy needs.

Springwise has spotted a number of innovations aiming to reduce the emissions associated with crop production while maximising yields. These Include an electrolyser to feed plants, solar powered water pumps and AI-powered smart greenhouses.