The PJM Interconnection board of directors on Dec. 7 approved the 2016 Installed Reserve Margin (IRM) Study results of 16.6% for 2017-18, which is slightly higher than the existing reserve margin.
The vote was reported in a Dec. 7 PJM publication that was posted online.
The study results re-set the reserve margin for the delivery years of 2017/18, 2018/19, 2019/20 and establish the initial IRM for 2020/21.The study examines the 11-year planning horizon, from June 1, 2016, through May 31, 2027.
Based on the annual IRM results, PJM recommended a 16.6% IRM for the 2017/2018, 2019/2020 and 2020/2021 Delivery Years and a 16.7% IRM for the 2018/2019 Delivery Year.
The 16.6% IRM for 2020/2021 calculated in this year’s study represents an increase of 0.1 percentage points with respect to the IRM computed for 2019/2020 in last year’s study. The mild increase can be attributed to changes in the PJM load model which this year features a flatter monthly peak shape, more specifically a higher August-to-July peak ratio.
The PJM Board at its Dec. 7 meeting also approved changes of almost $260m to the Regional Transmission Expansion Plan to incorporate both baseline and network upgrade changes.