The Greenhouse is driven by solar and wind energy. Sunlight is separated into visible and infrared light. Visible light passes through the roof to drive photosynthesis. Infrared light is trapped in the roof canopy and is ducted from there to the seawater evaporator. Thus solar energy converts seawater to water vapour.
The structure acts as a 'wind-catcher'. It faces into the prevailing daytime wind to assist ventilation. Fans are required under most conditions although these were unnecessary in Tenerife. The wind-fan combination moves air through the front evaporator and chills the sea water which then provides cooling for the rear condenser and, thus, the production of fresh water.
The electricity requirements are modest and, in the absence of grid power, can be provided by photovoltaic panels without the need for batteries, inverter or standby generator. The Tenerife Greenhouse was built on a wind farm with power supplied by the wind turbines on site. There are thus potential synergies between the Seawater Greenhouse and both wind and solar power.
The overall process is extremely energy efficient. 1kW of electricity expended on pumping will remove 500kW of heat. Water can be produced at low energy costs (<3kWh/m3).
