Mystic.io

Sep 21, 2018

Author Dive Brief: Tight load conditions that pushed the ISO-New England grid to the brink on Labor Day were partially due to an unplanned outage at Exelon's Mystic Generating Station — the plant at the center of an ongoing federal debate over fuel security. The 1,700 MW natural gas plant tripped offline during the afternoon of Sept. 3 due to a fault in a power line connecting it to the grid, said Dan Dolan, president of the New England Power Generators Association, a trade group. Exelon did not immediately respond to request for comment. Dive Insight: The outage at the Mystic plant, located near Boston, highlights the issues at stake in contentious debates over fuel security in New England and grid resilience at FERC. On Sept. 3, ISO-NE implemented emergency operating procedures , purchasing power from neighboring regions and calling for voluntary conservation as real-time prices topped $2600/MWh. ISO-NE said at the time that errors in its load forecast and unplanned outages caused the situation. Dolan said the grid operator later informed stakeholders that the Mystic plant was involved. "We have heard from ISO-NE that Mystic was offline due to a transmission outage — its interconnection to the grid," Dolan said. "That certainly contributed to the issues, in addition to missing the load forecast." Exelon could not be reached by publication time to comment on the Mystic outage. ISO-NE does not release outage information for individual plants and declined to comment on whether Mystic was involved. "We don't identify resources that undergo forced outages, nor any financial charges or credits for any specific resource," spokesperson Marcia Blomberg said via email. "That's market-sensitive, confidential information." Two sources with knowledge of ISO-NE market conditions confirmed that Mystic tripped offline due to an issue with its interconnection to the grid. They requested anonymity because they were not authorized to share the information. Blomberg said there were no forced outages on the ISO-NE transmission system that day, but that distribution lines not overseen by the grid operator could have caused other issues. "As I understand it, there were problems at one location on the sub-transmission system," she said. "The ISO doesn't operate the sub-transmission system and can't 'see' in real time what's happening on that system." The Mystic outage is likely to give ammunition to critics of ongoing price reforms at ISO-NE and FERC that could benefit plants with onsite fuel supplies. In May, the grid operator asked FERC for a waiver from its market rules to keep Mystic online with ratepayer support past 2022. The plant is essential not only for its generation capacity, ISO-NE said, but because it provides financial support for the sole LNG import facility in New England. The first round of comments in that fuel security proceeding are due today. In its filing earlier this month, ISO-NE proposed to treat fuel-secure plants like Mystic as "price takers" in wholesale auctions — not allowing them to set price — until it can complete its capacity market rewrite. The issues at stake in the fuel security proceeding echo larger questions about grid resilience animating the swirling debate over coal and nuclear bailouts at the federal level. Last year, the Department of Energy asked FERC to approve cost recovery for plants with onsite fuel supplies, widely seen as an effort to prop up uncompetitive coal and nuclear generators. FERC rejected the request in January, but opened a broad proceeding on resilience — the ability to "bounce back" from outages — that still considers issues of fuel security. A key argument from backers of Mystic and the DOE plan is that plants with onsite fuel supplies are more secure and resilient than those that must be fed by a pipeline. President Trump has weighed in on the debate, saying "you can blow up a pipeline," but coal is "indestructible." In June he directed DOE to design a bailout package outside of FERC. Critics of the DOE proposal and the Mystic cost recovery waiver argue that onsite fuel supplies have little to do with system resilience. The vast majority of outages are caused by problems with the transmission and distribution system, they argue, so subsidizing plants with fuel onsite will do little to make the grid more secure. An unplanned outage caused by a power line fault is likely to lend credence to those arguments, and not for the first time in ISO-NE. In January, right before FERC rejected the DOE bailout plan, New England's sole nuclear plant went offline due to a transmission issue , forcing the ISO to purchase emergency power from its neighbors. Follow Gavin Bade on Twitter