These figures are reached by only taking into account the most suitable sites, excluding national parks, areas of outstanding natural beauty, higher grade agricultural land and heritage sites.
The calculations of the land needed exclude rooftop solar panels. Ministers have resisted calls for solar panels to be made mandatory on new-build housing. Kitting out a new-build home with renewables, high-grade insulation and other low-carbon features costs less than £5,000 for a housing developer, but retrofitting it to the same standard costs about £20,000, with the cost borne by the householder. Housing developers are among the largest donors to the Conservative party.
I think these are the two most important points in the article tbh. Seems like we could off-set the need to build in national parks etc to meet this potential by adding more solar to roof tops. However, Tories gotta Tory and God forbid the housing developers lose profits. Still great to see what is achievable. We must increase pressure in the government to achieve it.