Fugitive emissions from BC’s natural gas industry

The environmental consequences of the expanded development of unconventional gas in North Eastern British Columbia, as laid out by Tyler Bryant and Matt Horne in The Tyee, include: risks of groundwater contamination from fracking; water use; the provision of electricity; the triggering of earthquakes; and the industrialisation of the landscape over large swaths of the NE of the Province. Apart from the emissions released by end use of the gas,  the largest single environmental impact—certainly the largest global impact—is likely to stem from leaks and deliberate venting of greenhouse gases during the production and transportation of the natural gas. Unfortunately, this is also one of the most poorly quantified risks.

According to British Columbia’s Ministry of Environment, about 108,000 metric tons of methane are being released into the atmosphere every year by the oil and gas industry. These emissions come from deliberate venting and through unintentional leaks—also known as fugitive emissions—from pipelines, wells and processing plants. While this sounds like a lot, according to the Ministry it only amounts to 0.3% of the total amount of natural gas produced in BC in 2011. However, compared to estimated leakage rates in the gas industry of the United States, which range widely from about 1 to 8%, these estimates are very low outliers. Even the lowest of the US estimates is three times as large as the BC figures.

Even small methane gas leaks matter, because methane is a much more potent greenhouse gas than carbon dioxide.  Following UN protocols, BC uses a factor of 21 over a 100 year period, which is to say that each ton of methane has the equivalent greenhouse effect of 21 tons of carbon dioxide. Recent research has shown that this factor (the global warming potential or GWP) should be revised upwards at least to 25 (as in the Fourth IPCC report in 2007) and perhaps as high as 33 if the secondary atmospheric effects of methane are taken into account (Shindell et al, 2009). If the warming of methane is calculated over shorter intervals, its relative effect is even more potent, with the GWP factor ranging from 72 to 105 for a 20-year period.

BC has legislated targets to reduce greenhouse gas emissions to 33% below 2007 emission levels by 2020, and to 80% below 2007 levels by 2050. The Province has huge resources of unconventional gas in the northeast, and both the BC Liberals and the BC NDP have plans to expand the gas industry and to encourage liquefied natural gas (LNG) exports to Asia through Kitimat. Even using the conservative official estimates, deliberate venting and fugitive emissions of greenhouse gases from the natural gas industry currently account for 9% of the Province’s emissions.

The latest research on fugitive emissions in the US is reviewed in a recent and freely available report by the World Resources Institute (WRI), Clearing the Air.  The report describes in detail the difficulties and uncertainties in measuring methane leaks and it lays out the steps that could be taken to improve the performance of the gas industry. WRI estimates that if the gas industry adopted all of the latest technologies to reduce methane leakage (their “Go-Getter” pathway), it would be possible to reduce the average methane leakage rate to 1% by 2020. According to BC’s figures, the industry in the province is already twice as good as that already.  But can we rely on these figures?


Steven Hamburg, the Chief Scientist for the US environmental advocacy group Environmental Defense Fund wrote:

Fugitive methane emissions from natural gas production, transportation and distribution are the single largest U.S. source of short-term climate forcing gases. The EPA [Environmental Protection Agency] estimates that 2.3% of total natural gas production is lost to leakage, but this estimate, based on early 1990’s data, is sorely in need of updating. The industry claims a leakage rate of about 1.6%. Cornell University professor Robert Howarth has estimated that [there are] total fugitive emissions of 3.6 to 7.9% over the lifetime of a well.

The latest (2013)  reporting from the EPA reduces their estimates of gas-industry methane leakage, compared to their previous estimates. Leakage rates for 2010 have been revised and reduced by roughly one-third, to approximately 1.6 % of the total gas produced. This revised figure is consistent with the US industry estimates (but still four to five times higher than BC estimate), but lower, or much lower, than most of the other published estimates.

clrair methane leakage

From the report Clearing the Air showing percentage methane fugitive emission estimates for the US natural gas industry. Note that all of the estimate ranges, even the low-end estimates, greatly exceed the BC Ministry of Environment leakage estimate of 0.3-0.4%.

What would BC’s fugitive methane emissions would look like if they were actually 2% of total production, rather than the 0.3% that the BC government claims?

A 2% leakage rate, applied to current gas production rates would result in emissions of about 720,000 metric tons of methane annually. Using a GWP range of 21 (the current factor) to 33 (what the latest science says) this amounts to carbon dioxide equivalents of 15 to 24 million metric tons. In comparison, current BC emissions for transportation (all our ferries, planes, trains and automobiles) amount to 23 million metric tons of carbon dioxide equivalent every year.

If BC  were to double or triple gas production, as promoters of the LNG industry are urging the Province to do, it is possible that future fugitive methane emissions alone could, just by themselves, exceed the total of the Province’s current greenhouse gas emissions from all other sources. Instead of drastically reducing the Province’s emissions over the next few decades, we could end up doubling them from methane leakage alone. But accidental leakage is not the whole story; there is also deliberate venting of greenhouse gases going on.

The natural gas from the Horn River Basin contains up to 12% carbon dioxide. This gas has to be stripped from the gas stream at processing plants and the carbon dioxide, currently some 3.2 million metric tons (BC Government spreadsheet) of it every year in the Province, is simply vented into the atmosphere. Non-combustion sources of greenhouse gases, like this vented carbon dioxide, are not currently subject to the BC carbon tax.  The BC NDP has promised that, if it wins the provincial election on May 14th 2013, it will phase in a tax on venting of greenhouse gases. At the current price of $30 per ton, this extension of the carbon tax would raise approximately $100 million per year.

Neither the BC NDP nor the BC Liberals (the other party with a realistic chance of forming a government) have plans to tax fugitive methane emissions, however. This is partly because these emissions are hard to measure accurately. But, if they were taxed, even accepting the Ministry of Environment’s claimed low methane emission rate of 2.3 million tons of CO2e, this would raise about $68 million annually. At fugitive emission rates of 15-24 million tons per year—which are in line with the low end of American estimates—the tax collected every year would be in the range of $450-$700 million. And these figures are calculated at current production rates, before any of the planned expansion for LNG exports.

Failing to tax these emissions and allowing industry to dispose of waste products or spills into the atmosphere without penalty is an effective industrial subsidy, to be paid for by future generations who will suffer the consequences of climate change. And importantly, as long as fugitive or vented emissions remain  untaxed, the energy  industry has no financial incentive to reduce them.

The economics of BC’s LNG plans are already strained and, if emissions were taxed at current carbon tax levels, the difference between fugitive emissions rates of 0.3% and 2% would likely make all the difference between a viable and a non-economic gas industry.  Accepting the lower figure, as the BC government currently does, means basically accepting the industry’s own assessment of the scope of the problem.

In the United States, serious efforts are being undertaken by academics, non-profit organisations and industry partners to measure emissions from the gas industry more accurately. Current BC government emission estimation methodologies rely on reporting of emissions by the producing companies themselves as well as on extrapolations of an exercise conducted in 2004 by CAPP,  “the voice of Canada’s upstream oil, oil sands and natural gas industry”. Considering the wide ranges of emission estimates made in the US using different methodologies, the BC government needs to exercise due diligence in bringing the best science and engineering to bear on this important problem, by conducting its own thorough and independent study of fugitive emissions. Unless BC is prepared to risk missing its own legislated targets, this work surely needs to be done before encouraging further expansion of the natural gas industry.