If natural gas is to function as a bridge fuel to renewable energy, a new power plant permitting deal in Massachusetts might model a path forward.
The Salem Harbor Power Station is a coal-burning power plant owned by Footprint Power LLC. It’s 63 years old — decades past the designed lifespan for such plants — and one of the worst polluters in the state. It’s scheduled to be shuttered in June, and Footprint has been angling to replace it with a 630 megawatt, $800 million, state-of-the-art natural gas plant that would take up one-third of the land area.
But the Conservation Law Foundation (CLF), a Boston-based advocacy group, went to court to stop the natural gas plant. Even though burning natural gas emits roughly half as much carbon dioxide as burning coal, CLF argued, that’s still enough to prevent Massachusetts from meeting the targets in the state’s Global Warming Solutions Act of 2008. That law calls for the state to cut its greenhouse gas emissions 25 percent below 1990 levels by 2020, and 80 percent below 1990 levels by 2050.
But then Footprint and CLF struck a deal. And on Thursday, Massachusetts’ Energy Facilities Siting Board approved it by a 5-to-0 vote.
According to the arrangement, the Salem plant would open in 2016, and then would have to start cutting its carbon emissions in 2026. By 2049, its emissions would have to be one-quarter of its emissions in 2016. To get there, Footprint could install carbon capture technology (admittedly an iffy prospect), cut its hours of operation, or invest in offsetting renewable energy projects.
So the agreement takes the “bridge” metaphor quite literally, setting a hard limit — written into the language of the plant’s permit — for how much time it can span. Another possibility could be combining this sort of agreement with “hybridization” — using natural gas and renewables in one interlinked power-generating system. The renewables guard against price swings for natural gas, and the natural gas ensures a reliable electricity supply on days when sunlight or wind is intermittent. Standardizing the end-date for natural gas use would create an incentive to ramp up the renewables over time until they could take over entirely. Since Massachusetts currently gets very little of its electricity from renewables, that could be a good practical approach to building that capacity and meeting the requirements of the Global Warming Solutions Act.
There’s one minor and one major caveat to this. The minor caveat is that it’s not clear if natural gas’ low prices are sustainable, in terms of the industry’s raw economic and geophysical realities. That could impact electricity prices, but that’s about it. The major caveat is that methane, which natural gas mainly consists of, is an extremely potent greenhouse gas itself — pound-for-pound trapping far more heat than carbon dioxide. And the latest studies suggest methane leakage throughout the industry could be bad enough to completely undo any climate advantage natural gas has over coal.
That said, leakage is at least theoretically fixable through infrastructure improvements. And the settlement apparently includes an agreement by Massachusetts to develop a plan to plug the leaks in its jurisdiction. And climate concerns aside, burning coal also emits all sorts of other pollutants that natural gas does not, including mercury, sulfur dioxide, nitrous oxide, and other toxics and heavy metals — many of which come with all sorts of destructive consequences for human health.