Record-Breading Temperatures
Northeastern parts of the U.S. faced a major heatwave June 17-21. New England saw record-high temperatures across the region for several days. Major cities like Boston, Hartford and Providence faced intense heat and temperatures peaked into the mid-90s during evening peak load hours. Heat index was also high and ranged between 100°-110°. First impact of the heatwave was seen June 18, when temperatures moved up too much above seasonal range. This was one of the hottest days for New England in June.
Impact on Power Grid
High temperatures increased the cooling demand during afternoon and evening peak load hours. Actual demand sharply moved up June 18 and reached 21.8GW, which was about 40% higher than average demand in this period of the year. Below screenshot shows the Enverus load forecast and percent to average peak load the morning of June 17.
Price Spike Event
NEISO declared a level 1 emergency alert on June 18 at HE18. RT prices jumped to $2K. DART spread was highly negative at this price event. This price event occurred due to capacity scarcity condition caused by actual load much higher than the forecasted load, unplanned generator outage and reduced imports from neighboring control areas. Ongoing planned generation outages also contributed the shortage of supply. Natural gas generation is the major resources of the New England to serve the peak load. An OFO notice from the AGT spiked the natural gas prices from $1.90 to $3.70 a day before this event. High natural gas prices also impacted power prices.
The heatwave June 18 shows that ISONE needs more diverse energy mix to reduce the reliance on natural gas. More renewables such as offshore wind and solar can reduce such events in the future. Improvement in transmission infrastructure will also improve the reliability of the grid.