Last week’s heat wave brought considerable pressure on New England’s energy grid and underscored the need to develop new sources of clean, reliable, low-cost energy. The six day long heat wave nearly broke records for demand both in New Hampshire and across the region. On the hottest day of the week, Friday, New England’s energy demand peaked at 27,377 megawatts, only 800 megawatts short of the all-time record. On the same day in New Hampshire, energy demand peaked at 2,210 megawatts, only 40 megawatts short of the all-time state record.
This prolonged period of high demand led to calls from ISO-New England to conserve electricity, created volatile swings in energy prices throughout the week, and brought significant changes to the region’s normal fuel mix. Energy prices fluctuated regularly from its normal average of about $38 per megawatt/hour to prices five to ten times greater, and, at one point even reached prices more than 17 times greater at over $600 per megawatt/hour.
Near record demand and high prices meant the costliest generation sources across the region were called on to keep the grid running. Oil-fired generation, which is rarely dispatched due to its high fuel costs, was called on heavily throughout the week. At one point during the heat wave, more than 3,500 megawatts of oil-fired generation in New England was running (more than 70% of the region’s oil-fired capacity), making it the third most used generation source behind only natural gas and nuclear and well ahead of coal, hydro, and all renewable generation sources.
New sources of clean, reliable, low-cost energy, like that of the Northern Pass project, would help the region better manage the grid through periods of high demand like last week. The 1200 megawatts of clean hydroelectric power of the Northern Pass would displace the need to call on some higher price, carbon emitting generation alternatives and provide a measure of price stability during a time when price spikes and volatility are common. The operation of the existing Hydro Quebec “Phase II” HVDC transmission line during last week’s heat wave provides an ideal example of the potential value of the Northern Pass during a period of high demand. The HQ Phase II line, which transports the same type of hydroelectric power that Northern Pass proposes to deliver, was the single largest source of energy for New England each day of the heat wave.
*Real time energy grid data from ISO to Go mobile application.