Lennar will build 1,500 new Colorado homes with geothermal heat pumps

Google X spinout Dandelion Energy and major U.S. homebuilder Lennar unveiled a partnership that aims to prove that proposition. The companies have pledged to build ground-source geothermal into more than 1,500 new homes in Colorado over the next two years, starting with Lennar’s Ken-Caryl Ranch development in Littleton, Colorado.

Just being able to tackle hundreds of boreholes at a time should more than halve the drilling costs that burden existing home retrofits, Kathy Hannun, Dandelion’s founder and president, said. Large-project economies of scale and designing homes around the high-efficiency heating and cooling that Dandelion’s system provides will yield further cost reductions, she said.

And by eliminating the need for new gas pipelines and reducing the peak electricity demands on the power grid, subdivisions built on this model could save a bundle on utilities as well, she said. That’s a key benefit cited in a January report from the Department of Energy, which found that widespread adoption of ground-source heat pumps, also known as geothermal heat pumps, could cut hundreds of gigawatts of peak demand and tens of billions of dollars in grid costs over the coming decades.