What would Northern Pass mean for our climate? | Conservation Law Foundation

What would Northern Pass mean for our climate?

Christophe Courchesne

The Eastmain Powerhouses from space (photo credit: NASA)

Beyond the discredited sales pitch that Northern Pass will lower electric rates in New Hampshire, the developers have repeatedly claimed that the power to be imported through the Northern Pass project will be “low-carbon,” “clean,” and “green,” with “no greenhouse gases,” and “no global warming.” The power will also, we’re told, “improve the quality of the air we breathe.” The developers have said, over and over, that the project “is expected to reduce regional carbon dioxide emissions by up to 5 million tons per year, the equivalent of removing from the road one million cars annually.” In fact, the study on which this claim is based – a report (PDF) commissioned by Northern Pass and authored by Boston-based energy consultant Charles River Associates – began with the assumption that hydro power is “zero-carbon.” Let me repeat that: the developers’ claim that the project will reduce carbon dioxide emissions by a net 5 million tons is based on their unexamined presupposition that the power to be delivered by the project has no carbon dioxide emissions at all.

There’s no other way to say it: this assumption is false.

You don’t have to take my word for it; read Hydro-Québec’s own research report (4.4 MB PDF) on the net greenhouse gas emissions of the Eastmain 1 Reservoir, flooded in 2005 (aerial shots here). In an Orwellian twist, the developers of Northern Pass have repeatedly cited this very same research.

The Hydro-Québec report found that net carbon emissions from Eastmain-1 were 500,000 tons in 2006 and 165,000 tons in 2009, and are projected to average approximately 158,000 tons per year on a long-term basis.  While certainly less than coal-fired power plants – PSNH’s Merrimack Station emitted more than 2.8 million tons of carbon dioxide in 2010 – 158,000 tons of net carbon emissions per year is far from “zero-carbon” or even “low-carbon” power.  Based on our own survey of reservoir greenhouse gas research, we have some serious questions about the report, and there is reason to believe that it understates emissions over time and per unit of energy generated. But the report does confirm that Hydro-Québec’s reservoirs will continue to emit more greenhouse gases per year than the natural environment they flooded. These emissions are locked in for decades if not centuries – unlike a power plant that burns fuel, you cannot turn off a reservoir.

When compared with the power plants that Northern Pass’s power could displace, new hydroelectric projects in their early years of operation are no cleaner in terms of carbon emissions.  According to the report, “it takes about five years for the accumulated CO2 eq. emissions to fall below the [natural gas combined cycle] value” (p.15). So, on a net and cumulative basis since its flooding in 2005, the Eastmain 1 Reservoir has had the same carbon dioxide-equivalent emissions as a modern natural gas power plant that has the same power output and began operating in 2005. 

The report also highlights what appears to be a clear difference between the net emissions of a newly impounded reservoir and the emissions of a reservoir that was impounded decades ago: a new reservoir emits more greenhouse gases, as the vegetation and organic material in the newly inundated area decompose.

This distinction is especially important when considering the contradictory stories we have heard about where Northern Pass will get its power. On the one hand, Northern Pass’s website claims (click on “Hydro-Québec” on this page) that “Hydro-Québec does not need to build any new generation to support this project.” On the other hand, it is clear that Québec is developing and planning vast new hydroelectric projects, many of which will require new inundation and reservoirs, as part of a concerted strategy to maintain and increase exports to New England and the northeast United States. See Erin’s blog post from yesterday for more on Vermont’s new long-term contract with Hydro-Québec. 

In fact, Charles River Associates’ fundamentally flawed estimate of carbon emissions reductions depends on the development of new hydro projects in Canada. And just ten days ago, in testimony to Massachusetts regulators, Northeast Utilities’ CFO David McHale stated under oath: “We already know for a fact that the utility Hydro-Quebec has initiated the construction of dams, and we’ve already entered into the record a discussion about the Eastmain Water Reservoir that will provide the water source. So this is not speculative. They’re building the dams and they will go into service; and that will be the primary source, if not the exclusive source, of energy that will flow over [the Northern Pass] line. . . . [T]hat is the full expectation.” What McHale was referring to is Hydro-Québec’s major new project in the vicinity of Eastmain-1 – the Rupert River project (project website here and explanatory animation here). Since 2009, this 918-MW project – now in the final stages of development – has newly flooded 346 square kilometers  – an area about the size of two Lake Winnipesaukees. That Northern Pass power will be coming from new projects means that Northern Pass will enable and contribute to the substantial carbon emissions associated with new reservoirs.  There has been no accounting of the potential emissions from the Rupert project and other future projects that Northern Pass may make possible, and how they would cut into the potential emissions reductions Northern Pass and Charles River Associates have claimed.

These inaccuracies and contradictions are being disseminated with hundreds of thousands of dollars in media buys, money which could have been invested in engaging in a collaborative process to rework the current proposal.  This situation makes CLF’s fight for a world-class, independent, and comprehensive permitting process all the more important.

CLF has been adamant that the Department of Energy must consider the environmental impacts – including greenhouse gas emissions – of the hydropower generation projects and any other power plants in Canada that will supply the Northern Pass project.  Given the developers’ recent announcement of new delays in their schedule, there’s still time for the Department of Energy to change course and answer our call for a regional, holistic analysis of the right approach to importing power from Canada, taking into account the truth about that power’s greenhouse gas emissions.

Before you go… CLF is working every day to create real, systemic change for New England’s environment. And we can’t solve these big problems without people like you. Will you be a part of this movement by considering a contribution today? If everyone reading our blog gave just $10, we’d have enough money to fund our legal teams for the next year.

Focus Areas

Climate Change


New Hampshire


Northern Pass

About the CLF Blog

The views and opinions expressed on this blog do not necessarily represent the opinions or positions of Conservation Law Foundation, our boards, or our supporters.