In an unusual turn of events, Thursday, September 7, 2023, marked a significant milestone in the ISO-NE region, setting a new record for the Annual System Peak. With demand soaring to 23,521 MW between 5-6 PM, it surpassed the previous peak-to-date recorded on July 6 by a substantial 1,200 MW. This remarkable occurrence is expected to stand as this year’s Annual System Peak, and it holds a unique distinction as the first-ever September peak in New England.
Thursday marked the third occasion this summer when we recommended curtailment to manage the potential peak demand, with the previous peaks observed on July 28 and September 6. Both these days came remarkably close to the July 6 record, emphasizing the unpredictability of selecting the highest demand day among them. However, the demand on Thursday was notably higher, solidifying its status as the definitive peak, pending any unforeseen surges in hot and humid weather for the remainder of the month.
An intriguing aspect of Thursday’s peak was the influence of behind-the-meter solar installations, which shifted the peak later in the day, as evidenced in the graph below. While demand typically tapers off after 6 PM, on Thursday, it experienced an unusual resurgence around 7 PM, persisting for about half an hour before declining again. This phenomenon, though observed previously, appeared more pronounced and sustained on Thursday. The graph also illustrates a slight dip in demand around 4 PM, likely attributable to curtailment measures. Throughout the day until 6 PM, demand closely aligned with our projections.
The Annual System Peak in September follows the atypical weather patterns witnessed across New England and the United States this summer. While many regions in the West and South experienced prolonged heatwaves, the Northeast enjoyed a relatively mild August and an exceptionally wet June. The September peak can be attributed, in part, to the temperate conditions during July and August.
Please note that the graph illustrates the actual and projected demand on September 7, 2023. This historic milestone highlights the dynamic nature of energy demand and our region’s evolving landscape of energy management. Stay tuned for further insights and updates as we navigate these unprecedented developments in the energy sector.