ERCOT: Up To Nearly 2,500 MW Of REP/NOIE Price Responsive Demand Seen During August 2019 Peak

ERCOT filed with the Texas PUC a report on demand response during the summer of 2019

As noted further below, ERCOT noted that ESI IDs may participate in more than one form of demand response (DR) and, when categorizing DR into individual categories, there may be double counting. This double counting is eliminated in the total amounts of DR megawatts listed by ERCOT

Data is collected from information provided to ERCOT by REPs and NOIEs

ERCOT said that the load reduction quantities reported in the table below represent those results for the peak week, hour-ending 17:00 (5:00 PM) for Summer 2019 (again, August 12 - 16). The day-to-day variability in response for 4-Coincident Peak (4CP)/NearCP and Price Response is a consequence of individual ESI ID and NOIE decisions about the cost-benefit of responding on a particular day. Significant overlap among competitive ESI IDs does exist across 4CP/NearCP, Price Response, Emergency Response Service (ERS) and Transmission and/or Distribution Service Provider (TDSP) Standard Offer Programs (SOPs). Significant overlap also occurs among NOIEs between 4CP/NearCP and Price Response, ERCOT said

The overlap can be significant and can result in an overestimate or an underestimate of total demand response. For example, if one was to calculate the total demand response resulting from the survey results and compared that total to the actual observed reduction in demand, the survey results would overestimate demand response by 2,609 MW on August 13 and underestimate demand response by 1 MW on August 16, ERCOT said

The basis for the overlap is that categories are behavioral and surveying the REPs and NOIEs does not allow ERCOT to definitively know the reason load responded on a particular day. Differentiating between price response and 4CP is difficult because they are not necessarily structured programs but incentives that exist in the market for load response. Some load may respond to a $9,000 price whereas other load may need the $9,000 price plus the value of 4CP to respond on a particular day, ERCOT said

On the other hand, the ERS program administered by ERCOT and the TDSP SOPs are programs that do not allow overlap as there is a prohibition on dual participation between the two programs. However, an ERS participant could curtail for 4CP or price. In summary, the 'Total System Level DR/PR' column in the table eliminates double counting and represents the best indication of overall demand and price response for that peak week, ERCOT said

ERCOT's report of the demand response amounts during the summer 2019 period stated above is below. A large version of the chart is available by clicking the image or clicking here

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