Home energy feedback meters: Knowledge is power

Last November, I wrote a post called "Getting savvy about standby power." In it, I mentioned a study out of the California Energy Commission that put a shocking price tag on the electricity our household appliances waste when they're in standby or low-power modes.

I then went on to talk about a number of actions anyone could take to reduce or eliminate this scourge from their household electricity consumption. Most of those tips boiled down to "unplug your gadgets when they're not in use."

The post, however, begged a larger question: Just how much does behavior play into the way we use energy around home? And, by extension, what's keeping us from behaving better?

Behavior matters
Many factors affect our home energy use -- from how drafty our windows are to the efficiency of our appliances to the number of people living in the house.

But what if we looked at a community where most of those variables were roughly the same, a community where the architectural and design features of each house were similar?

That's exactly the experiment being run in a community outside Sacramento. The homes were built in the last few years as part of the Department of Energy's Building America program, a public/private partnership aimed at constructing cost-effective zero-energy homes by 2020.

The normal-looking, single-family homes have been improved in a number of ways: the insulation and windows are higher-than-average quality, the air ducts are sealed to prevent leaks, they have tankless water heaters, etc. They're also equipped with two-kilowatt photovoltaic systems.

On average, these features have cut families' energy consumption by 40 percent compared to the program's benchmark (60 percent if the solar panels' generation is factored in).

Despite these improvements, the homeowners' behavior has emerged as a big driver of energy use. Some families are consuming double or half the amount of energy as their neighbors, even though all their homes were constructed with the same or similar features.

The take home message: Behavior matters. And it may mater even more as we improve the efficiency of our homes.

Getting feedback
Rather than lecturing people about their wasteful behavior, what if we gave them information about the consequences of their actions?

Enter the feedback meter. It's a little device that links up to your home's inverter and gives a real-time readout of energy use. A decent, low-end model can cost as little as $150.

Studies in the United States, Canada, Scandinavia, the Netherlands, and UK have shown that people who install them save between 5 and 15 percent of home energy use.

For people who already live in efficient homes, the savings could be greater, because behavior is a bigger driver of their home energy use.

That's why the Building America pros studying the community in Sacramento are launching a project this summer to see just how much this feedback matters. Just like the Prius's center console helps people drive their cars more efficiently, the researchers believe feedback meters could help homeowners "drive" their houses better.

Considering features
If you're in the market for a meter, you'll want to consider a few things:

• How accurately does the meter measure consumption? Some may measure your use in 10-kilowatt increments, others in 100-kilowatt increments. The smaller the increments, the more accurately you'll be able to tell how certain actions affect your home energy use.
• Is the meter wired into the wall or is it wireless? You may be more likely to monitor the energy use of certain appliances if you can carry the device around your home and see how certain actions tip the needle.
• Does the meter integrate with a photovoltaic system? For people with solar panels on the roof and a desire to be self-sufficient, it's often nice to know how your energy consumption stacks up against what you're generating on-site.

The more features the meter has, the more it's likely to cost. But if you're gadget-inclined, the upgrade may be worth the money.

After all, knowledge is power -- or, in this case, power savings.

Noah Buhayar is a fellow at Rocky Mountain Institute.