Massachusetts Attorney General Maura Healey on Dec. 12 joined recent calls from U.S. senators and presidential candidates for ISO New England to reform its wholesale electricity market rules to support more renewable energy resources and invited state residents to do the same.

"Every day, we see the impacts of climate change in our communities, and our best solution to combat this crisis is to transition away from dirty fossil fuels and toward cleaner renewable energy," Healey said in a news release. "We want to give ratepayers the tools to make their voices heard and help reshape our state's energy system for future generations."

To that end, the attorney general's office launched a petition for residents to sign demanding that ISO New England "adopt energy market rules that promote affordable clean energy, healthy communities, and climate protection."

Through its current rules, New England's grid operator protects "older, dirtier, and more expensive energy resources" while obstructing renewables, according to the attorney general's office. Specifically, Healey is seeking changes in how ISO New England maintains grid reliability through its capacity market and other essential grid services. Currently, natural gas accounts for about half of ISO New England's winter capacity, with petroleum the second-largest resource, according to S&P Global Market Intelligence data.

In response to the attorney general's initiative, a grid operator spokesperson pointed to recent reforms the ISO New England already has initiated on renewable energy and energy storage.

While its integration of batteries remains a work in progress, including through its still-pending compliance with the Federal Energy Regulatory Commission's landmark order on energy storage, some market participants have been pleased with ISO New England's progress so far.

Sunrun Inc., for instance, in February applauded the grid operator, as well as states within its domain, for working with the residential solar and battery specialist on reforms. Those ultimately allowed the company to secure a bid to supply 20 MW of capacity to ISO New England starting in 2022, sourced from approximately 5,000 battery-backed solar homes aggregated into a virtual power plant.

But some market analysts have noted costly excess capacity, largely fossil fuel-fired, supported by ISO New England rules, a phenomenon reflected in many regions throughout the U.S., as identified in a new S&P Global Market Intelligence investigation. Consulting firm Grid Strategies, in a report released in November, cited approximately 3,900 MW of excess capacity on New England's wholesale power grid, with an estimated annual cost of more than $156 million.

ISO New England President and CEO Gordon van Welie in November defended the grid operator from criticisms by a Senate delegation that included presidential candidates Sens. Bernie Sanders, D-Vt., and Elizabeth Warren, D-Mass., who called on the grid operator to give greater consideration to renewables to maintain the reliability of its grid.

The grid operator's competitive auctions were a "second-best solution," he acknowledged. But New England states "have been clear that they are not in favor of pricing carbon emissions within the … wholesale electricity markets," van Welie said.