Twilight for Wasting Energy: DOE Combats the Vampire in Your Microwave with New Efficiency Standards

Thanks to new energy efficiency standards proposed last week, DOE Secretary Steven Chu has a new credential on top of his Nobel Prize: he’s a vampire slayer – one that specializes in eliminating “vampire” energy waste while saving consumers billions of dollars.

Look around your kitchen. Chances are there’s more than one device telling you what time it is – your oven, microwave, perhaps a radio or a wall clock. What about the other rooms in your house? Every blinking light, display, or warm device in your home is using energy, even when you’re not there. In fact, a 2008 study found that new, unoccupied homes in California used 117 watts before anyone had even moved in.

Much of this energy use goes to what's commonly called "standby" or “vampire” energy use.  Products waiting to provide their main service suck up power to keep their electronic controls at-the-ready and for the multitude of glowing and blinking displays and signals throughout our home.  And, believe it or not, those blinking lights suck up a tremendous amount of energy. The same study found that low-power mode use of devices accounted for about 13 percent of residential electricity use for an average California home in 2006. And this number is only growing with the increasing number of devices in our homes.

To combat this “vampire” energy use, Congress directed the Department of Energy in 2007 to set standards for standby and off-mode energy use for all products subject to national energy efficiency standards.  A just-released DOE proposed efficiency standard for microwaves shows the wisdom of eliminating standby energy waste and will provide large savings for consumers and the environment.

The proposed standards would protect consumers -- who are unlikely to consider or even have information about the efficiency of a microwave’s clock when making a purchasing decision -- but do pay for its energy use over time. The standby energy use for all the products in our homes really does add up. For example, the average home described above would cost the homeowner about $100 a year just for standby power (at 10 cents per kWh), regardless of whether they flipped on a single switch. 

In microwaves, standby energy includes power for lighting the clock and other displays, the cooking sensor and power supply and control boards.  According to DOE’s analysis and testing, the technology exists today to reduce this energy use while still providing full functionality to consumers and saving them money on their energy bills. The proposed standards would require displays and other standby features of microwave ovens to use energy more efficiently by limiting the standby energy used for most microwaves to 1 watt. (Built-in and above-the-range units that combine a convection oven and microwave would be allowed to use up to 2.2 watts in standby, but these combo units comprise a small share of total sales.) DOE estimates that the savings from these proposed standards will add up to a cumulative 410 trillion BTU over 30 years. For comparison, this is approximately equal to the energy used in one year by 2 million US homes. DOE  also estimates that these improvements will save consumers a net present value of $1.82 to $3.6 billion over the life of the rule. As in many cases of energy efficiency, a few seemingly small improvements can save a lot of money.

The proposed standards would also reduce harmful air pollution. According to DOE’s analysis, the standards would reduce CO2 by 31.6 million metric tons of CO2 cumulatively over 30 years and would reduce NOx emissions by 25,600 tons over the same time period.

The energy savings from this rule have been a long time in the making. DOE originally proposed standards for microwave standby energy use in 2009, but postponed them in order to update the test procedure. DOE updated the test procedure in March of last year and sent the proposed standard rule to the Office of Management and Budget for review last June. Due to what has become a very lengthy review period at OMB, the proposed rule is just now being issued over 6 months later and still needs to be finalized after notice and comment.  Microwaves are one of many rules for which energy and consumer savings have been delayed by a lengthy OMB review and we urge DOE and OMB to move expeditiously to release the other rules so consumers can realize their full benefits.

We are pleased to see DOE moving forward with this efficiency standard. DOE’s proposed standards will slay the energy waste “vampire” in new microwaves, and both consumers and the environment will be better off.