The crisis in Ukraine has rekindled arguments that the U.S. should export shale gas, supposedly to diminish the threat posed by Russia’s “energy weapon.” Sadly, few seem to care about diminishing the threat posed by climate change, since it has become increasingly clear that LNG would make things worse.
I explained back in June 2012 why “exporting liquefied natural gas (LNG) is bad for the climate.” That analysis predated multiple studies that make clear that “by the time natural gas has a net climate benefit you’ll likely be dead and the climate ruined.”
So we’re in double jeopardy with LNG. First, natural gas is mostly methane, (CH4), a super-potent greenhouse gas, which traps 86 times as much heat as CO2 over a 20-year period. So even small leaks in the natural gas production and delivery system can have a large climate impact — enough to gut the entire benefit of switching from coal-fired power to gas.
Sadly, many recent studies find that there are sizable leaks. A February study from Stanford reported that “A review of more than 200 earlier studies confirms that U.S. emissions of methane are considerably higher than official estimates. Leaks from the nation’s natural gas system are an important part of the problem”.
That study of studies found a best estimate for life-cycle natural gas leakage of a whopping 5.4 percent (+/- 1.8 percent). And that means replacing coal plants with gas plants would be worse for the climate for more than 6 decades.
The situation is even worse with liquefied natural gas (LNG) because the LNG life-cycle shown above is itself so energy intensive, consuming a considerable amount of natural gas and transportation fuel. Cooling natural gas to about −162°C (−260°F) and shipping it overseas for use in distant countries is costly and energy-intensive:
The process to bring the gas to such low temperatures requires highly capital intensive infrastructure. Liquefaction plants, specially designed ships fitted with cryogenic cooling tanks, regasification terminals and domestic transmission infrastructure all make LNG relatively expensive in construction and operational cost.
When you factor in the energy and emissions from this entire process, including shipping, you get a total life-cycle energy penalty of 20 percent or more. The extra greenhouse gas emissions can equal 30 percent or more of combustion emissions, according to a pretty definitive 2009 Reference Report by the Joint Research Centre of the European Commission, ”Liquefied Natural Gas for Europe — Some Important Issues for Consideration.”
So it is safe to say that by the time LNG has a net climate benefit, you’ll be dead and the climate ruined.
It bears repeating that, if avoiding catastrophic climate change is your goal, we do not want to build a global energy system around non-leaky, non-liquefied natural gas (see IEA’s “Golden Age of Gas Scenario” Leads to More Than 6°F Warming and Out-of-Control Climate Change).
BOTTOM LINE: Investing billions of dollars in new shale gas infrastructure for domestic use is, as we’ve seen, a bridge to nowhere — especially until we put in place both a CO2 price and regulations to minimize methane leakage. The extra emissions from LNG completely eliminate whatever benefit there might be of building billion-dollar export terminals and other LNG infrastructure, which in any case will last many decades, long after we need a nearly carbon-free electric grid. At best, investing billions in LNG infrastructure is a waste of enormous resources better utilized for deploying truly low-carbon energy. At worst, it helps accelerates the world past the 2°C (3.6°F) warming threshold into Terra incognita — a planet of amplifying feedbacks and multiple simultaneous catastrophic impacts.