By Dan,
posted on Friday, April 15, 2011.
The speed at which misinformation can proliferate is clearly
evidenced by the coverage in the press this week of "Methane and
Greenhouse-Gas Footprint of Natural Gas from Shale Formations," a
study by Cornell University's Robert Howarth and Anthony
Ingraffea.
Howarth et. al. looked at the lifecycle of greenhouse-gas
emissions from shale gas, concluding it was worse than coal, an
absurdity that uses data comparing "apples to oranges," according
to Michael Levi with the
Council on Foreign Relations. "Alas, his analysis is based
on extremely weak data, and also has a severe methodological
flaw (plus some other questionable decisions), all of
which means that his bottom line conclusions shouldn't carry
weight."
This paper is selective in its use of some very questionable data
and too readily ignores or dismisses available data that would
change its conclusions," says Dave McCabe, an atmospheric scientist for
the Clean Air Task Force.
"Consumer beware!," says John Hanger, former head
of the Pennsylvania Department of Environmental Protection.
"The author of any life cycle analysis can get to a result he
wants if he has a desired outcome quite easily, because life cycle
analysis swings greatly on the assumptions, data inclusions, and
data exclusions."
"Practically every paragraph includes an assumption,
simplification or choice by the authors that tends to increase the
calculated environmental impact of natural gas," said Geoffrey Styles at The
Energy Collective. "Whether that's the result of bias or merely a
series of judgment calls, it undermines confidence in the final
conclusions. … As lifecycle analysis, this earns a failing grade,"
Styles says.
"What he has done in his analysis is deviated from what are
accepted standards, accepted by EPA, DOE, the IPCC, European
Trading Scheme, California Air Resources board, where essentially
the denominator that they use to calculate the impacts of various
greenhouse gases is an agreed upon hundred years; Professor Haworth
uses 20 years," Melanie Kenderline,
executive direction at MIT's Energy Initiative.
Kenderline has also said that if the capacity of natural gas were
used in lieu of coal capacity, carbon dioxide emissions from power
generation would be cut about 20 percent nationwide, "which is an
enormous reduction." But Howarth chose to ignore power-plant
emissions.
"Howarth's gas-to-coal comparisons are all done on a per energy
unit basis," CFR's Levi says. "That means that he compares the
amount of emissions involved in producing a gigajoule of coal with
the amount involved in producing a gigajoule of gas. Here's the
thing: modern gas power generation technology is a lot more
efficient than modern coal generation, so a gigajoule of gas
produces a lot more electricity than a gigajoule of coal. The per
kWh comparison is the correct one, but Howarth doesn't do it.
This is an unforgivable methodological flaw; correcting for
it strongly tilts Howarth's calculations back toward gas, even if
you accept everything else he says."
The scientific consensus shows that using selective data to
manipulate an outcome is not a study based on sound scientific
principles. In fact, it's the very antithesis of what real
scientists work on each and every day. Presenting misguided
and badly researched material does not belong in the very real
daily discourse that's happening in this country when it comes to
the future of energy.
"I worry about what this paper says about the peer review process
and the way the press treats it," Levi says. "These reviewers don't
appear to have been on the ball. Alas, this sort of thing is
inevitable in academic publishing. It's a useful caution, though,
against treating peer review as a mark of infallibility."