Utilities have long used demand response to deal with high wholesale electricity prices or generation shortfall. What was once accomplished with phone calls to large industrial customers or one-way controls on aggregated residential loads is now done in near-real time with sophisticated two-way communication. Yet, despite the fact that this strategy has become an integral part of grid operations in the U.S., there has been no agreement on a definition of demand response.
The Peak Load Management Association (PLMA) set out last year to develop a consistent definition for demand response to use across its three training courses on the topic. A demand response dialogue that included several experts in the field took place in September 2016 and was recorded and archived on the PLMA website. At the 2016 PLMA conference later that year, the discussion continued with a panel presentation, Defining the Evolution of Demand Response: From 1.0 to 3.0 and Beyond.
The white paper from these discussions breaks down demand response into three periods beginning with the first interruptible tariffs for large commercial and industrial customers. Demand response was primarily used to provide energy (MWh) and capacity (MW) during periods of high wholesale prices, shortfall of generation or transmission capacity or unexpected emergency grid-operating situations. Utility staff contacted a commercial customer, usually a day or hours ahead of a forecasted event, to manually change power consumption onsite. Also, residential customers voluntarily allowed utilities to install load-control devices to cycle their water heaters and air conditioners. Verification usually came from the utility meter which was read on its regular cycle.
Current demand response strategies provide more precise energy and capacity to support the wholesale marketplace, along with sophisticated, near-instantaneous ancillary services such as non-spinning and spinning reserves and frequency and voltage support. Measurement and verification occur in almost real-time measurements (either utility or non-utility) and often serve as confirmation of customer performance during demand response events. Two-way communication also allows for greater customer feedback and engagement.
Demand response is evolving to be a component of broader distributed energy resources both behind and in front of the meter. The service benefits demand response offers in this capacity, both to the grid operator and to the customer, include volt/var control, renewable energy integration and localized distribution system congestion management. The future of demand response may move away from traditional utility control to automatic, pre-programmed triggers based on price thresholds.
Two upcoming courses expand on PLMA’s demand response white paper to provide utility and regulatory staff and industry trade allies with a greater understanding of the evolution of demand response. Join subject matter experts from PLMA member organizations in Portland, Oregon, Sept. 26 or in San Francisco, California, Oct. 25.
Presentations will cover current technology and market conditions, utility case studies and more. Demand response will be compared to other load management strategies, and participants will discuss how to design a load management portfolio that serves your utility’s needs.
The training is open to all industry stakeholders, with significantly discounted rates to PLMA member organization staff.
Source: Peak Load Management Association, 8/8/17