Environmental Engineering Reference
In-Depth Information
Climate Change Impacts of Shale Gas
Production
JOHN BRODERICK* AND RUTH WOOD
ABSTRACT
The climate change impacts of shale gas are considered from a number
of perspectives. When normalised per unit of energy produced,
greenhouse gas emissions from production and combustion appear to
be comparable to, or marginally higher than conventional sources of
natural gas, with direct CO
2
from combustion dominating. Substantial
uncertainties in such estimates remain, and recent atmospheric stud-
ies of methane emissions suggest that on-site measurements and
emissions inventories from the US oil and gas industry may be sig-
nificant underestimates. Shale gas is not a low-carbon energy source,
and in the absence of an effective climate regime new gas reserves
could have a substantial impact on cumulative CO
2
emissions and
hence the extent of climate change. The quantity of emissions that will
likely cause 2 1C of mean surface temperature rise is very low relative to
current emissions and trends, with a restricted time period within
which it is prudent to burn natural gas. The position of shale gas as a
'transition fuel' and the relevance of comparison with coal as a fuel
source rely upon the assumptions that: (1) it completely displaces the
use of an alternative more-carbon-intensive fuel; (2) growth in energy
demand does not outpace carbon intensity savings; and (3) it does not
jeopardise the development of low- and zero-carbon energy systems. It
is not clear that these criteria are currently being met. Without a global
