Science - November 5, 2010
Greenhouses are not net energy producers
In spite of its name, the energy-producing greenhouse turns out to generate less energy than it uses.
The 'Sun & wind greenhouse' for growing pot plants currently generates 82 percent of the energy it needs. In theory the greenhouse can generate 100 percent of its heating requirements, but the costs incurred for underground heat storage are too high. The other two demo greenhouses only produce more energy than they use if they can sell their surplus heat to other companies.