New England Electric Grid Under Precautionary Alert

The electric grid for Boston and the surrounding region operated under a precautionary alert on Tuesday as the surplus of power was expected to narrow to a razor-thin margin amid soaring temperatures.

ISO New England, the electric grid operator for the six-state region, began operating under a precautionary alert late Monday as energy supplies tightened.

Wholesale electricity prices over the past 24 hours have signaled tightening supplies, with the grid reporting nearly $430 per megawatt hour (MWh), a ten-fold increase over prices when the system is not stressed.

To prepare for Tuesday’s scorching heat, the grid directed power plant operators not to do any testing or maintenance that would affect electric reliability.

New England joined other regional grids in the eastern half of the country in deploying exigent strategies to balance the supply and demand of electricity. Besides increasing imports from adjoining regions and asking power plant operators to defer maintenance, they called on stand-by units to boost the supply of electricity.

Temperatures in Boston are forecast to approach 100 degrees Fahrenheit (38 degrees Celsius) Tuesday afternoon, according to the National Weather Service.

ISO New England forecast that electricity demand would approach 26,000 megawatts (MW) late Tuesday, short of the record high of 28,130 MW set in August 2006.

Last month, ISO New England predicted electricity demand to reach 24,803 MW under normal weather conditions, and up to 25,886 MW during any periods of above-average summer weather, such as an extended heat wave.

The latest forecast predicted that demand would peak Tuesday evening at 25,800 MW. Surplus capacity was expected to fall to 266 MW, a departure from a typical margin of several thousand megawatts during more temperate weather.

(Reporting By Tim McLaughlin; Editing by Mark Porter)