Using Water Heaters to Store Energy, Integrate Wind Power

Interest in demand response, which enables consumers to adjust their electricity use when the power system is stressed, has sharpened recently thanks in part to its potential to help integrate wind energy into the power system.

Traditionally, demand response involved enlisting interested consumers who were willing to reduce their electricity use during peak energy periods or when prices spiked, usually for a few hours at a time.

The Bonneville Power Administration and several utilities are partnering on pilot projects to test the ability of demand response to help manage the electricity grid and integrate wind energy into the system.  To integrate wind energy, the rest of the power system needs to be able to increase production when wind generation drops off and decrease production when wind increases to keep the system in balance. Some demand response load could provide the flexibility to help in this integration by reducing electricity use at peak times and also storing the wind's power at a moment's notice.

"Not all demand response load can be used to respond to the variation in wind's output, " notes Ken Corum, senior economist for the Council. "But appliances like water heaters and space heaters, or cold storage plants have the ability to absorb that energy when it needs to go somewhere."

"Two years ago, there was very little going on in this area," says Corum. "The growth in wind power development in the region has definitely heightened the interest in demand response as a possible tool to make wind work in our system."

The pilot project that the Council is helping to sponsor is funded largely by the Bonneville Power Administration and will test the ability of  things like water heaters and cold storage plants to balance wind generation in the power system. The project is expected to begin in late 2010 and end in 2012.

"And, if these pilot projects prove successful," notes Corum, "it should also help to lower the cost of integrating renewable resources into the power system."