It seems hard to believe that the developments can generate enough renewable energy to meet their needs at the required standards. For residential buildings alone, at a conservative average of 50m2 per home, 49,000 homes using 35kWhr/year will need 85 Gigawatt hours per year of new generation capacity paid for within the homes price. This is well beyond the capabilities of developers to construct, for example. wind turbine farms.
If the assumption is that it will be via photovoltaics this too seems unlikely. An average home of 50m2 would need 1750 kWhr/year. At typical solar efficiencies this would require 17m2 of solar panels, which is all of the South-facing roof capacity, for every single house.
Does the plan have confidence that developers can design and afford net zero energy homes within the required standards, or does it expect that nearly every development will need “offsetting” measures? What absolute standard is the plan going to apply to for offsetting, or what are the “futureproofing” approaches?