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Shale gas and atmospheric CO2: help or hindrance?

Shale gas and atmospheric CO2: help or hindrance?
The Lake Side Power Station natural gas power plant in Utah, USA (Photo: Mscalora)
The Lake Side Power Station natural gas power plant in Utah, USA (Photo: Mscalora)
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The Lake Side Power Station natural gas power plant in Utah, USA (Photo: Mscalora)
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The Lake Side Power Station natural gas power plant in Utah, USA (Photo: Mscalora)
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Since peaking in 2005, US domestic energy CO2 emissions have fallen by 8.6 percent. A new report asserts that up to half of this reduction may be down to "energy switching," as generators switch from coal to shale gas (partly on cost grounds), which emits about half the CO2 when burned. Yet the same report, from the Tyndall Centre for Climate Change Research, questions the wisdom of touting shale gas as a low-carbon technology, with its authors actually asserting that "the exploitation of shale gas reserves is likely to increase total emissions." How so?

While it's tempting to look at the reduction in America's domestic energy CO2 output in isolation, the atmosphere doesn't care where CO2 comes from. It's all the same to it. In the US, a reduction in domestic coal consumption in the energy sector has coincided with an increase in the country's coal exports. US coal usage may be down domestically, but that is not to say that that same coal isn't being put to use elsewhere.

In fact, the report's authors calculate that of the total of 650 million tonnes of potential CO2 emissions avoided by reducing coal consumption to date, 340 million have been emitted in other countries (mainly in Europe or Asian) that have imported the coal instead.

The problem is that though shale gas may emit less CO2 at the power station than coal, it appears this is insufficient to offset the emissions from the exported coal. "Despite lower-carbon rhetoric, shale gas is still a carbon intensive energy source," said Dr. John Broderick, lead author of the report Has US Shale Gas Reduced CO2 Emissions?.

The net effect of the rise in shale gas consumption and coal exports could well be an overall increase in CO2 emissions, the authors suggest. "We must seriously consider whether a so-called 'golden age' would be little more than a gilded cage, locking us into a high-carbon future," Broderick said.

The report concludes that without a "meaningful" cap on global CO2 emissions (which is to say that the contribution made by shale gas must eat into, not add to, that of coal), shale gas is likely to do more harm than good. And the report is not optimistic. "Were an abrupt, internationally simultaneous, fuel switch from coal to gas to occur, the remaining safe carbon budget may be consumed less quickly," it concludes. "In the ‘real world’ these conditions are unlikely to coincide."

Source: Tyndall Centre for Climate Change Research

14 comments
14 comments
zevulon
what this 'professor' is really complaining about is the developing world coming out of poverty. the ONLY proven method of doing this for the past few hundred years since developing countries left wood behind for peat spermaceti is to begin burning fossil fuels to provide energy for running industrial processes like smelting mining, infrastructure build out etc........
this professor is not seeing the obvious hear, that slowly shale gas is being developed as a source that will begin displacing coal to the extent it can globally. this will work ONLY to lower particulate pollution and emissions than it the levels that would OTHERWISE attain without development of shale gas.
because other countries WOULD be developing themselves industrially regardless of our choice to go on shale gas or not. coal exports notwithstanding.
z
Viator
The real question is "So What?" The main driver for keeping this planet warm is water vapor with CO2 being a minor component. But, folks just keep on chasing rabbits.
"We live in a society exquisitely dependent on science and technology, in which hardly anyone knows anything about science and technology." - Carl Sagan
abe
Agree with zevulon.
And if we where using coal, how would that stop us from exporting it as well? We would just increase production.
Really nice to say, hey we'll lower our carbon emissions that are 100x more than yours and you should live in a hut!
ivan4
Anything from the Tyndall Centre is suspect in reasoning.
As zevulon says their biggest problem appears to be wanting to keep the undeveloped nations in poverty by denying them the necessary power generation equipment to allow those economies to develop.
The other thing that most people ignore is the fact that more CO2 in the atmosphere is beneficial to all growing things be it trees, plants and food crops. Trying to reduce CO2 is tantamount to condemning people to starvation.
Pikeman
Strange how it is the industrialized nations that have the money and energy to care about the environment.
The Hoff
Ice cores show that carbon dioxide levels in the atmosphere have remained between 180 and 300 parts per million for the past half-a-million years. In recent centuries, however, CO2 levels have risen sharply, to at least 380 ppm. It's true that human emissions of CO2 are small compared with natural sources. But the fact that CO2 levels have remained steady until very recently shows that natural emissions are usually balanced by natural absorptions. Now slightly more CO2 must be entering the atmosphere than is being soaked up by carbon "sinks". Deforestation would be a logical culprit. Other forms of energy would be a logical answer.
Bob Stuart
The Coal is really a side issue for the economists. The increase in natural gas supply is via fracking, which directly releases methane, a far worse greenhouse gas if leaked instead of burnt. The carbon used to power water clean-ups in fracked areas for centuries has to be counted in as well. And all the investment in gas plants has been at the expense of sustainable technology.
Nicolas Zart
I don't think anyone should blame petroleum and coal for all the evils and certainly it has fed and helped bring to fruition the industrial revolution. But we have other alternatives to create energy today that pollute less these days. Unfortunately, these techniques are somewhat expensive, at least initially and there is no push bringing them out to developing countries. In the meantime, we'll continue seeing more and more of these Business-politico shenanigans where only a few will benefit financially, leaving the rest of the world to pay for that privilege. Machiavelli couldn't have written it any better.
rstid
Amazing illogic. Because we will use more gas and export more coal (rather than burning it ourselves) then abundant natural gas is bad????
Synchro
Ivan4, some nice dumb cherry picking there. By the same measure, fish do really well in water, so we should welcome flooding of low-lying cites.
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