2009 State of the Market Report
Recent DR Initiatives
DRR Participation in Ancillary Services Markets
DRR Type I
DRR Type II
ASM markets launched in January 2009 allow LSEs to offer DRR for operational reserve purposes similar to generation resources. Type II resources can currently offer all ancillary services products, whereas Type I units are prohibited from providing regulating reserves. This is because the physical requirements required of regulating reserve-eligible units are too demanding for Type I resources – they need to be able to respond to small changes in generation within 4 seconds. Type I units were also prohibited from providing spinning reserves until February 2, 2010. Table 4 below shows the participation rates for DRR in energy and ancillary service markets in 2009.
DRR Type I resources became eligible for spinning reserves on February 2, 2010.
DRR participated in nearly all eligible markets in 2009. Type I resources offered only supplemental reserves, whereas Type II resources offered energy, regulation and spinning reserves. Quantities between day-ahead and real-time did not change substantially. DRR provided on average 1.6 percent (spinning reserves) to 5.3 percent (supplemental reserves) percent of the total cleared amounts for the AS products. Cleared quantities were largely constant across all months of 2009, except for Type II spinning reserves. These quantities averaged just 2 MW prior to September 1, 2009 and 36 MW thereafter.
Table 4: DRR Participation in Midwest ISO Markets
Average quantities in MW, 2009