Spot power prices surge as MISO, PJM, SPP issue heat-related advisories

The Midcontinent Independent System Operator and the PJM Interconnection have issued hot weather alerts for the start of the upcoming week, and the Southwest Power Pool issued a resource advisory, as extreme heat is set to hit the Central and Eastern US and drive up power demand and prices.

MISO's hot weather alert covers its entire 15-state footprint in the US Midwest and South and is effective from 8 am ET July 28 to 10 pm July 29. The grid operator also will be under a conservative operations advisory for the same period because of "extreme heat with heavy forecasted loads projected [and] capacity limitations due to forced generation outages," according to MISO's July 24 notice.

"Based on our current forecast, MISO has enough capacity to meet demand next week," spokesperson Brandon Morris said in a statement to Platts, part of S&P Global Energy. "We are constantly working with our member utilities and fellow grid operators to ensure reliability, especially when the system is experiencing high demand."

PJM's hot weather alert covers its entire footprint, which includes 13 states and Washington, for July 28 as hot weather continues throughout the region, the grid operator said in a July 25 statement. PJM also issued hot weather alerts for its Mid-Atlantic and Southern regions for July 26-27.

Southwest Power Pool, which manages the electric grid for 14 states in the US Central and Southwest, issued a resource advisory for its entire footprint for 11 am CT July 28 to 9 pm July 29. The advisory was declared because of forecasts for potentially high peakloads and lower wind-powered generation leading into peak hours, as well as a possible increase in resource outages, according to SPP's July 24 notice.

Wholesale power prices

MISO's Indiana Hub on-peak day-ahead power for July 28 delivery rose $83/MWh on the day to trade around $165/MWh during July 25 trading on the Intercontinental Exchange. By comparison, Indiana Hub day-ahead on-peak locational marginal prices have averaged $69.92/MWh so far in July, about 59% higher than the July 2024 average, according to MISO data.

SPP's South Hub on-peak day-ahead power for July 28 delivery rose $47.50/MWh to trade at $63/MWh on ICE. By comparison, South Hub day-ahead on-peak LMPs have averaged about $47.44/MWh so far in July, about 9.3% higher than the July 2024 average, according to SPP data.

PJM's AEP Dayton Hub's on-peak day-ahead power for July 28 delivery rose about $54.75/MWh to settle at $134/MWh on ICE. The highest real-time power prices in PJM as of midday July 25 were in the Dominion Zone, where the locational marginal price had reached $273.17/MWh.

Elsewhere in the East, real-time power prices in New York Independent System Operator territory fell on July 25, with the highest prices in Long Island Zone K at $79.81/MWh and in New York City Zone J at $77.32/MWh. ISO New England's real-time power prices hit the triple digits around midday, with the highest price in Northeast Mass Boston at $116.54/MWh.

Market conditions

MISO forecast systemwide peakload at nearly 123.5 GW July 28 and 120.5 GW July 29. For comparison, MISO's peakload so far in July has averaged 108.1 GW, 6.3% higher than the July 2024 average.

MISO's all-time peakload is 127 GW, set on July 20, 2011.

Population-weighted temperatures across MISO's footprint are forecast to average 83.1 degrees Fahrenheit over July 28-29, according to CustomWeather data. MISO has historically seen population-weighted temperatures averaging 75.8 F across its footprint for the same two-day period in July. The population-weighted temperature in MISO so far in July has averaged 77.3 F, according to CustomWeather data.

SPP forecast systemwide peakload to at 53.9 GW July 28 and 53.4 GW July 29. For comparison, SPP's peakload so far in July has averaged 47.6 GW, nearly 2% above the July 2024 average.

SPP's peakload record for this month is 54.394 GW, set on July 15, 2024. Its all-time peakload is 56.184 GW, set on Aug. 21, 2023.

Population-weighted temperatures across SPP's footprint are forecast to average 86.8 F over July 28-29, according to CustomWeather data. SPP has historically seen population-weighted temperatures averaging 81.4 F across its footprint for the same two-day period in July. The population-weighted temperature in SPP so far in July has averaged 80.9 F, according to CustomWeather data.

As of noon on July 25, PJM said it expected to serve a peak load of around 154 GW on July 28. So far this month as of July 23, PJM's peakload has averaged nearly 135.7 GW, 3.6% higher than the July 2024 average.

PJM's record summer peakload is 165.563 GW, set in 2006, according to the grid operator's website.

Population-weighted temperatures across PJM's footprint are forecast to average 86.7 F July 28, according to CustomWeather data. The population-weighted temperature in PJM so far in July has averaged 78.8 F, according to CustomWeather data.