A sustainable energy project that was supposed to set the standard for zero emissions buildings has performed so badly that the consultant team is using it as an example of how not to proceed.

Max Fordham, the environmental consultant on a headquarters for wind farm developer Renewable Energy Systems, was funded by the DTI to monitor the project for two and a half years. It is now presenting its findings at seminars to clients and academics.

Bill Watts, senior partner at Max Fordham, said: "Everybody clams up when we say we want to point out the problems we encountered along the way. We took the decision to be brave and see if we could learn from the experience and make future schemes better."

The heating needs of the headquarters, known as Beaufort Court, were supposed to be met by a biomass boiler fuelled by the crop Miscanthus, or Elephant Grass, grown on 5 ha of land around the building. After three years the crop had not taken and straw and wood chip had to be used instead. When a crop was harvested in 2005, it provided 22 MWh of heat compared with the building's requirement of 170 MWh.

The project also encountered problems with its underground heat store and combined solar thermal and photovoltaic panels.

The ground water cooling system also dramatically underperformed - it was seven times less effective in practice than it was in theory.