Gone to earth: in search of cheap interseasonal thermal storage for low-cost zero energy houses.

The paper compares the design and measured performance of the relatively conventional Autonomous House and the earth-sheltered Hockerton Housing Project, both in Nottinghamshire, England. These are both attempts by the authors at making houses for the United Kingdom climate that need no non-renewable energy inputs, but are comparable in cost with conventional houses. The conclusion is that high thermal mass combined with superinsulation is effective in giving "zero heating" performance, but it makes sense only if the house is designed for an extremely long life.