The competition, and particularly the shortlisted entries, demonstrate the fact that although it is relatively easy to make calculations supporting 'zero CO2' standards, it is a lot more difficult to integrate the energy generation requirements to meet the higher 'zero heating' standards suggested in gir 53.
It is also significant that, while most entrants adopted a sophisticated approach to fabric insulation, few demonstrated an equivalent understanding of what is required to improve air-tightness in order to reduce adventitious ventilation.
Even less attention was paid to water heating (which represents the largest thermal load) and no entry dealt adequately with the provision of fuel for cooking. Similarly, the use of fuel for lighting and appliances is the largest source of carbon-dioxide emissions but few entries acknowledge this or demonstrated a capability to size renewable sources such as photovoltaic collectors.
Robert and Brenda Vale are known for their holistic approach to environmental issues. The integration of energy generation and the production and spaces for working and living demands lifestyle changes. Very few architects and developers are responding to the challenge, though the zero-energy development at Beddington by Bill Dunster for the Peabody Trust will provide the next significant development in this direction.
What this competition was hoping to achieve was a variety of new approaches to high-density sustainable dwellings and a new, imaginative approach to the development of brownfield sites for housing. In this respect, the competition entries were perhaps less imaginative than the assessors hoped for.
The fact that the two winners were architects who already have an extensive track record in low-energy design showed that experience is held in a relatively small number of practices, whereas one of the aims of the competition had been to reach a wider and younger audience. If the government has any chance of meeting the very challenging but necessary Kyoto targets agreed to by the European Community, low-energy, high-density housing provides the only realistic solution to future urban development.