Energy Efficiency is Not What It's Cracked Up To Be

A building is a system, and just like you can't save yourself rich, you can't achieve energy independence by endless investments in energy efficiency, for they are not additive, but instead, they run into the brick wall of diminishing returns on investment. Energy efficiency extends the franchise of the fuels involved, and needs to be seen in that context. They belong in the utility model.

To set up a methodology of justifying capital investment at the building level based on energy savings is counter productive to the extent that it locks us into the subscription models of fossil fuel use. The implicit and unexamined assumption of fossil fuel burning creates buyer lock in, and prolongs dependence on those fuels. This is not to say energy efficiency is not important. It is. However, energy efficiency is a secondary issue not a primary one.

We need to go back to square one, and that is the question what energy do we need? How much do we need as heat, and how much do we need as energy (electricity). After that we should look into however much energy can be generated at the building from renewable sources, solar, wind, and geothermal. Those decisions are make or buy decisions. Then comes the trade off decision of energy efficiency, namely how much can we lower installed capacity through energy efficiency. This will cause a much more constructive view of energy efficiency. It will also produce more of a systems look at the whole building.

Naturally, part of the consideration is also how can we successfully harvest peak load energy such as solar and wind energy, and in residential construction Domestic Hot Water (DHW) storage is our friend, and not the enemy, as long as we use well insulated storage tanks, to harvest our intra day needs of heat energy. Thus tankless hot water heaters are a no-no in almost all cases and should be stripped of their Energy Star ratings, because they lock us in to excessive use of peak cost energy, since they work on demand by definition, and the whole notion of the smart grid is learning to store energy and diminish on-demand usage. These devices represent a false economy which in the long run will lower the value of your building by more than any savings they could ever produce.