Dive Brief:

• ISO New England (ISO-NE) expects declining annual load and summer peak demand through 2028, largely due to solar and energy efficiency additions, according to its 10-year system outlook published Thursday.
• The region remains energy constrained with gas pipelines full, which the grid operator called the "greatest risk to power system reliability." However ISO-NE said it does have sufficient capacity resources lined up, and power imports can also help meet demand.
• Grid modernization efforts will be necessary. The ISO cited growth of inverter-based technologies and behind-the-meter solar as reasons it will need transmission upgrades and control system improvements to ensure reliability.

Dive Insight:

ISO-NE's outlook shows total net annual use of electric energy declining by 0.4% annually, with summer peak also declining 0.4% annually by 2028. Without solar generation and efficiency, the operator said its baseline forecast showed energy consumption would grow by 1.1% annually, and summer peak demand would grow by 0.7%.

Gross winter peak demand will grow at 0.6% annually, said the ISO, but the net annual peak demand decreases by 0.6% annually as a result of regional efficiency additions.

According to the report, the region has installed capacity to meet the winter peak demands, which are 6,000 MW to 7,000 MW lower than the summer peak demands, but other actions may be necessary, including cutting load.

"This is because the region relies on natural gas to fuel much of its generation, but sufficient fuel may not be readily available when the weather is cold," the ISO said. "While new resources are being proposed for New England, energy-security and reliability issues may arise from energy-production limitations resulting from just-in-time fuel sources, intermittent renewable resources, and compliance with environmental regulations."

The report says resource-adequacy studies show the "most reliable and economic" spot to develop new resources is in the Northeastern Massachusetts/Boston and Southeastern Massachusetts/Rhode Island areas, due to anticipated fossil fuel retirements and load growth.

"Transmission improvements are underway in these areas, and new fast-start generation is under construction," according to the report. "This will help meet the regional and local capacity needs and improve system reliability, but delays in the construction or additional retirements would make meeting local resource-adequacy requirements less certain."

Generally, the region is expecting more resource additions than retirements, and the grid operator "projects that adequate resources will be available to meet net [installed capacity requirements] for the next 10 years."