Gas generators oppose Maine transmission line

Three natural gas-fired power generators are opposing plans for a large power transmission line to be installed between Canada and Maine, saying the renewable power transmitted by the line would put their plants out of the money and weaken electricity reliability.

Calpine, Dynegy and Bucksport Generation filed comments with the Maine Public Utilities Commission (PUC) against Central Maine Power's proposed project to install a 145-mile (233km) 1,200MW line to ship hydro generation into the state from Canadian plant Hydro-Quebec. The three opposing generators own and operate about one-third of the installed electric generating capacity in Maine.

While the new line would lower costs for ratepayers, the generators asserted that large-scale, out-of-market resources within the ISO-New England market "may have profound unintended consequences" for reliability. Plants could be forced to retire earlier than expected, directly affecting reliability and the diversity of supply, the filing said. The high-powered transmission line could also impede development of alternative renewable energy projects in Maine, such as solar and wind farms, the generators noted.

Electric grid operator ISO-New England earlier this year said it would have to rely on emergency actions such as rolling blackouts in order to protect the grid as early as the winter of 2024-25 as a result of inadequate natural gas supplies. The grid's increasing focus on natural gas-fired generation is expected to add to its reliability issues in the coming years, with gas-fired burn expected to increase by about 30pc by 2023, averaging 1.3 Bcf/d (37mn m³/d) by 2022.

Central Maine Power said it does not object to the generators' intervening in the proceeding with the PUC provided that the commission does not restart the case's clock, as it is already six months into a 12-month proceeding schedule.

The PUC has scheduled multiple technical conferences on the line in the coming months and hearings in early August. Final objections to the project are due in September.

Calpine owns the 552MW Westbrook Energy Center gas-fired power plant located in Westbrook. Dynegy owns the 543MW Casco Bay Energy Facility, a gas-fired plant in Veazie. Bucksport owns a 243MW facility fueled by natural gas, diesel and biomass in Bucksport.