Residential Appliance Demand Response Testing

Achieving the goals of the Smart Grid will require deployment of a wide array of communicating devices, enabling customers and utilities to better manage energy use at home across the electric grid, respectively. In the residential sector, smart appliances are a significant part of realizing the full potential benefits of the Smart Grid. These appliances not only achieve high levels of energy efficiency during normal operation, but also are capable of responding to Demand Response (DR) events – where utilities need to reduce electric load quickly during peak usage times to avoid widespread power outages, or at the consumer’s request in response to high electric prices. Appliance manufacturers are incorporating this functionality and are beginning to release DR-capable products into the market. At the 2012 ACEEE Summer Study, Southern California Edison (SCE) presented laboratory test results for a DR-capable clothes washer. (Mitchell et al. 2012) Since that time, SCE has tested multiple other appliances (dishwashers, clothes washers, and refrigerators) from multiple manufacturers. This paper shares the comprehensive results including each device’s reaction to DR events initiated during the various stages of operation. The results show that typical responses offer either a large load reduction for a short duration DR event, or a smaller reduction for a longer event. The manner of response varies between manufacturers and appliance types, which could create challenges for utility DR program design. Additionally, the newer appliances are very energy efficient and have lower average connected load, and therefore reduced DR potential, than appliances of a slightly older vintage. Furthermore, Energy Star® recently incorporated “Connected” functionality into several of its appliance specifications. This paper includes a discussion of the specifications and test methods and how they align with or run counter to current utility DR programs and future plans.