Proponents of the longstanding practice of using water heaters as a demand response resource are calling on the Department of Energy (DOE) to reconsider its proposed water efficiency standard. The draft efficiency standard, crafted in 2010, would limit the size and type of water heaters and discourage the use of such appliances to manage load and excess power when needed. Demand response proponents are calling on DOE to revise its proposed standard to accommodate grid-interactive water heaters. A recent bill was introduced to Congress that would create a separate class for those water-heaters that are grid-interactive. This exemption would protect water-heaters that are 75 gallons or greater and that are designed for demand response programs.

In an interview with Megawatt Daily, RAP principal Rich Sedano said, “[h]aving an exemption for grid-interactive water heaters may not be as efficient as the standard proposed by DOE, but it would contribute toward national goals of integrating renewable resources and encouraging demand response.” As the share of variable renewable resources increases, so too will the need for flexible, demand-side resources. Grid-interactive water heaters acting as storage devices can provide flexibility which will aid with the integration of variable renewable resources, boost grid regulation services, and reduce the need for new peak generation—all of which drive down the cost of providing electricity service.

In light of the changing needs of the power system, having DOE craft an exemption or change the standard “seems like a worthwhile thing to try and do,” said Mr. Sedano.