How are the Eden Project domes heated?

The domes of the Eden Project are the largest geodesic domes built yet, reaching 60m in height in places and spanning enough land to house 29 football pitches. They are made of lightweight galvanised steel tubing of varying sizes, created and cut by a computer.

In place of glass, ethyltetrafluoroethylene (ETFE) has been used to enclose the giant domes of the Eden Project. It is a strong highly-transparent foil, which is only 1% of the weight of glass.

The hexagonal and polygonal pillows of ETFE consist of three or four layers into which air is pumped by a solar-powered heating system.

The heating of the biomes is assisted by the insulating quality of the ETFE panels. It is also facilitated by sustainable climate control mechanisms, whereby the heat of the sun is stored in the thermal mass of rock upon which the domes are constructed. This regulates the daily temperature and can radiate heat during the night.

Neato!

http://www.webpages.uidaho.edu/arch504ukgreenarch/casestudies/edenproject1.pdf