Gas-burning plants taking the place of coal-fired facilities would result in net reduction in greenhouse gases, researchers say
Fix the fugitive methane problem in the natural gas sector, and liquefied natural gas can be an important “bridge” to a decarbonized world.
So said Diane Regas, executive director of the Environmental Defense Fund, speaking at the annual Globe conference in Vancouver two years ago.
Liquefied natural gas (LNG) has been touted for its potential to reduce global greenhouse gases, if it is used to displace coal power and to backstop renewable energy.
With an abundance of natural gas, clean hydroelectric power and short shipping distances to Asia, B.C. could develop an industry that could be good for the economy and the environment, according to LNG supporters.
The problem with such assertions is that there has been a distinct lack of serious analysis specific to B.C. to back them up.
But a recent study involving the University of Calgary, Johns Hopkins University, the Massachusetts Institute of Technology and Southern Methodist University finds that, depending on where it is used, LNG from B.C. could indeed result in net greenhouse gas (GHG) reductions, if it displaces coal power.
B.C. Energy, Mines and Petroleum Minister Michelle Mungall cited the study when responding to questions about LNG and B.C.’s climate change policies.
“There is evidence indicating that global emissions would decrease if British Columbia were to export LNG to Asian markets to replace other energy sources such as coal, including the recent (joint university) study,” she said in a written statement to Business in Vancouver.
The study builds on research done in 2014 by the U.S. Department of Energy’s National Energy Technology Laboratory. The latter study concluded American LNG used to replace coal power or pipeline gas from Russia in Europe and China could in some, but not all, instances result in net GHG reductions.
For the latest joint university study, researchers conducted a life-cycle analysis specific to LNG shipped from Kitimat to China, India, Japan, South Korea and Taiwan.
“Overall, our results suggest that there is a net environmental benefit in terms of greenhouse gas emissions reduction when importing Canadian natural gas for electricity generation in the five countries considered,” the paper states.
BC Green Party Leader Andrew Weaver, who was a climate scientist before going into politics, said the study is “a good academic analysis,” but said the authors’ own supporting evidence precludes them from forming the “opinion” that there would be a net benefit.
“It is an opinion that is not based on the evidence that they presented,” he told BIV.
He notes that the authors acknowledge there are “uncertainties” about upstream methane emissions from natural gas production.
The most they can assert is which country, based on its infrastructure, would provide the greatest GHG reductions, he said.
“They don’t know what the base emissions are from fugitive emissions,” Weaver said. “They just don’t know — it’s uncertain. So they can’t say anything about the overall number.”
Methane is shorter-lived than carbon dioxide, but as a greenhouse gas it is magnitudes worse in terms of its heat-insulating properties.
The study acknowledges that “the ultimate magnitude of the greenhouse gas emissions associated with natural gas production systems is still unknown.”
“Fugitive emissions are uncertain,” Sarah Jordaan, an energy and environment researcher at Johns Hopkins University’s school of advanced international studies, told BIV.
That uncertainty doesn’t necessarily undermine the conclusions of the study, she feels, but said it does highlight that “there are a lot of opportunities to improve measurement, mitigation and regulation in this area. And in many cases it can actually be economic and a benefit for the company.”
The recent study assumed annual exports of 18 million tonnes of LNG from Kitimat — roughly the amount a large LNG plant would produce and sell annually.
The process of liquefying, transporting, regasifying and burning natural gas adds emissions, so the amount of GHGs generated or avoided will change according to variables such as transport distances and infrastructure efficiencies or inefficiencies.
The study focused on “country-level parameters” — ocean transportation and infrastructure, for example. It concluded the net reductions in GHGs from using LNG from B.C. would range from 6.5 megatonnes (Mt) of CO2 equivalent (CO2e) to 9.9 Mt CO2e.
Japan and South Korea are already major LNG users, whereas India, China and Taiwan still burn significant amounts of coal for power. Those three countries, therefore, would generally represent the greatest gains, since there is more coal power to displace.
Adebola Kasumu, a researcher with the University of Calgary’s Hydraulic Fracturing Initiative and lead author of the study, cautions that the benefits accrue only if LNG displaces higher-carbon energy sources like coal, and that the numbers can vary, not just from country to country, but within each country, based on a variety of factors such as transmission efficiency.
“It shows that the carbon intensity and the climate implications resulting from the use of the B.C. LNG in electricity generation in those import countries which we cited in our paper are significantly sensitive to country-level parameters … based on the data that we had,” he said. “If we had another set of data for country-level parameters, those numbers could change.”
One concern with LNG is that it could prevent the wider adoption of renewable energy.
“There are valid concerns, due to low prices of natural gas, that there could be a negative displacement factor and that renewables could be displaced in some situations,” Jordaan said.
But LNG can also help promote better integration of renewables. Since solar and wind power are intermittent and often erratic, they require either large-scale battery storage or firm dispatchable power (coal, hydro, nuclear) as a backstop.
Gas-fired thermal power not only is cleaner than coal — 50% to 60% cleaner — but it also ramps up and down quickly when needed.
“You can imagine that it provides a more flexible grid, which can be lower-carbon overall, if this renewable-natural gas combo is coming in and displacing ... coal-fired power plants,” Jordaan said.
As for the concerns over fugitive methane emissions, it’s a problem that can be fixed through engineering and regulations.
According to the Environmental Defense Fund, the gap between Canada’s commitments as part of the Paris Agreement and its climate action plans in 2016 amounted to 45 million metric tonnes of GHGs per year. Reducing methane emissions by 45% would take care of 25% of that gap.
Environment and Climate Change Canada is planning new regulations aimed at reducing methane emissions from the oil and gas sector by 40% to 45% below 2012 levels by 2025.
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