Energy inefficiencies

We use a lot of energy cooling our homes and offices in the summer and heating them in winter. The energy used to accomplish these tasks is electricity, created mostly by burning fossil fuels or burning fossil fuels directly. I see something counterproductive here. We need to find a way to store all that excess heat we try to dispose of all summer, collect it and release it all winter. Perhaps even store all that cold we try to eliminate all winter, collect it and release it in the summer. Or both!

But we're not only wasting a lot of energy modifying the temperatures of our buildings, the buildings themselves aren't very efficient at maintaining their temperature. In North America at least, we still build our houses out of timber and insulate to R-20 in the walls. We currently have the technology to build green, net zero energy homes that are R-44 in total. Net zero means the amount of energy the house can produce is equal to what it consumes. This adds 20% to the cost of construction and I'm being extremely pessimistic in that estimate. So a $200,000 home now costs $240,000 (land costs not included) and does away with the need for a furnace and possibly an air conditioner, which not only practically eliminates the need for a natural gas bill, but also significantly reduces the electricity bill too. Throw in some surplus energy sold back to the utility and you could make that $40,000 back in less time than it took to pay off that mortgage.

So why aren't we doing it? Why aren't we building these houses?