The new pound;1.8 million high-tech centre includes a high mass south-facing wall which absorbs heat and distributes it round the building. At night there is cooling by natural ventilation, and a central atrium draws warm air up and out of the building.
Large windows in the north-east and west facades maximise natural light. A collection system gathers rainwater for domestic use and - subject to planning permission - two small wind turbines will be located on the roof to power the building.
The centre, which cost pound;733 a square metre, proves that a commercial building can also be environmentally sustainable. It will be used 24 hours a day, providing online new technology courses and skills to businesses in south-west England.
Gilbert Snook, the college's head of estates, said: "It is clear the Government will start to force the pace soon, especially given the latest report that recommends all further education colleges be environmentally accredited by 2010.
"There are very few exemplar buildings in the region that meet the challenge of being built with useful and inspiring environmental details but to a sensible budget. We hope it will prompt others into action now they can see for themselves what can be done."
The architects, Kay Elliott, designed the structure with the assistance of the consulting engineering firm, Hoare-Lea. Jerry Barnes, a spokesman for Hoare-Lea, said: "All too often buildings are designed and then adapted to demonstrate environmental principles through the simple addition of commercially-available environmental bolt-ons.
"We took the opposite approach - to design in sustainability from the outset.
"The resulting building is a low-energy, sustainable design."