To integrate 309kwp of photovoltaics into a cluster of mixed use buildings on two brown-field sites in London to raise the awareness and acceptability of solar power within an urban environment. The buildings will include social housing, private housing and commercial business units. The developer is a major London housing association. A detailed study of two different sites with different briefs for site layout, building design, energy management and energy use. At Site A, PVs will be incorporated into today's good-practice energy-efficient buildings and linked to a site network. Energy will be shifted between buildings to avoid export to the grid. At Site B, solar energy will be used to power electric cars as part of an holistic sustainable zero Energy Development for the 21st century.