Check out these pie charts of annual energy use in two houses. This came from some modeling we did for a 70% energy savings laboratory home. Both houses are the same size and architecture (2,185 square feet floor area). The house on the left is the Benchmark house, as defined by the Department of Energy's Building America program. The house on the right is a possible Lab Home with 70% energy reduction relative to the Benchmark house. Most of the savings were the result of adding insulation, better windows, and ultra-efficient heating, cooling, and hot water equipment. The overall size of the pie charts is indicative of the annual energy use.

I want to point out the three areas that are bolder: Lighting, Appliance, and Miscellaneous Electric Loads (MEL's). Lighting energy was reduced 70% in this model by switching from a normal mix of incandescent and fluorescent lighting to 90% fluorescent lighting (CFL's and linear fluorescent). This is why the relative lighting energy use is 7% for both houses. The model assumed a switch from standard to Energy Star certified appliances.

What I really want to talk about is that MEL's category! That's the category that all of these electronics we buy fall into. TV's, computers, phone chargers, clock radios, and so on, are all accounted for here. In this model, we could not reasonably assume the builder could save any energy in this category. So, what we now spend 11% of our energy bill on will turn into more than a third (37%) of a super-efficient house! Lighting, appliances, and MEL's together jump from a quarter of the energy use to two thirds of the total.

There are ways to save energy in this category. On one side, the manufacturers will likely have to address the efficiency of their equipment and how they use the energy, specifically in the off and standby states. This standby power consumption has been a topic in the news on and off lately (finally!). I wrote about some easy controls for this a while ago in my post Home Electrical Energy Monitoring for the Homeowner. Another route is home automation and intelligent controls. I'll explore this topic more in the future, and maybe Bob Gatton can address it in his blog as well.