The rise in renewable power supplies is increasing the need for energy storage to address the ebb and flow of wind, solar and other intermittent energy resources into high voltage lines. Now, some are saying that water heaters and other common appliances in homes and businesses could help meet that storage need. An advanced grid that responds better to changes in power use--combined with chips or controllers installed in appliances, such as hot water heaters and freezers--can turn the devices into the equivalent of batteries that could provide power storage. The Northwest Power Conservation Council estimated, for example, that increasing the temperature of 3.4 million electric water heaters would result in 2,056 MWh of energy storage. Turning up the heat in water heaters by 10 degrees could double the amount of storage, according to Ken Corum, an economist with the conservation council The temperature of the water could be raised above the baseline, usually around 120 degrees, when wind energy is at full throttle. Storing the energy as heated water would alleviate the demand on the grid when the wind dies down, helping to level out the intermittency of wind energy resources. Increasing the temperature in electric water heaters would mean they would kick on less frequently because the temperature in the tanks would drop more slowly to the set point. Corum said appliances that have controllers built into them could react to signals from utilities and offer valuable storage under the right conditions. \u201cIf we can get these controllers in water heaters at reasonable costs, and someone doesn\u2019t come up with a better solution, they could provide significant storage potential.\u201d Unlike California, electric water heaters are widespread in the Northwest because of the availability of relatively inexpensive hydropower. However, the study provides a glimpse of storage devices in our homes and businesses that may be getting short shrift--whether powered by electricity or natural gas. Corum also pointed out that water heaters could be more energy efficient if incoming cold water replacing warm water--used in a shower for instance--was not immediately heated. Assuming the hot water is not all used up, the cold and hot water in the tank is stratified, he noted. The cold water sits on the bottom of the column and the hot water on top. \u201cUnless you use up all the hot water, you won\u2019t know it wasn\u2019t heated for quite a while,\u201d Corum said. More storage is possible from lowering the temperature in freezers. Freezer temperatures, however, could not fluctuate as much as water heaters because of the need to keep food chilled to keep it from spoiling. Another strategy for reducing load on the system is to be able to remotely control the heat used in clothes dryers. Allowing the clothes to be air tumbled without heat for a few minutes at a time can quickly alleviate excess load. \u201cIt is a last-ditch defense against system collapse,\u201d Corum said. Southern California Edison has a successful program in place that allows it to reduce air conditioning demand at peak periods. Some fear, however, remotely controlling appliances to reduce peak energy consumption would be akin to allowing Big Brother into people\u2019s homes.