Develop and Field Test Flexible Demand Response Control Strategies for Water Pumping Station and Industrial Refrigeration Plant

In California, reducing the state’s carbon energy footprint with more intermittent renewable generation, and less predictable loads call for innovative ways to balance generation and loads. This project field tests one such approach—flexible demand response (DR)—at representative sites in two sectors: water pumping and industrial food refrigeration. These sectors are ideal for flexible DR because they store energy—as potential energy in water in storage tanks, and stored thermal energy in frozen food warehouses—that can be dispatched in response to a shortfall or excess in generation capacity.

At the water pumping site, station operators reliably reduced power demand for an extraction pump by approximately 30 percent, for up to four hours, without affecting the station’s ability to serve its customers. Site management expressed enthusiasm for investigating broader application of flexible DR at additional sites. At the industrial refrigeration site, the team successfully achieved flexible DR on average at 25 percent of total baseline compressor demand by either increasing or decreasing demand for more than 12 hours. In addition to primary objectives, this project also demonstrated the effectiveness and reliability of the bidirectional OpenADR 2.0b standard, and identified additional on-site candidate loads for flexible DR, such as electric floor heaters and electric forklift truck chargers.

The team accumulated a wealth of knowledge and began its transfer through whitepapers, and interactions with stakeholders, utilities and a range of stakeholder communities in California. Technology transfer is also anticipated through direct interaction with service providers, such as systems integrators, software implementers, and DR aggregators. Flexible DR advancement will enable the California grid to accept more renewable energy, reduce the amount of solar curtailment occurring today, help maintain and enhance system reliability to lower energy costs, and better balance generation and load to capture avoided ancillary service costs. Moreover, economic benefits from additional revenue streams for water pumping and industrial refrigeration DR services could, at least partially, be passed on to California consumers, resulting in lower water service and food storage costs.