Chapter 6: Shale gas and climate change
108. The UK is committed to achieving
a number of climate change objectives. National[194]
and local organisations[195]
expressed to us concerns that greenhouse gas emissions from extraction
and use of the UK's shale gas might not be compatible with these
objectives. This chapter examines the issues.
Greenhouse gas emissions of shale
gas
CARBON FOOTPRINT COMPARED TO CONVENTIONAL
GAS AND LNG
109. In December 2012 DECC commissioned
a study (the 'MacKay' report) into the greenhouse gas emissions
associated with shale gas extraction and use. This was published
in September 2013.[196]
The MacKay report found that the carbon footprint[197]
of shale gas extraction and use is comparable to gas extracted
from conventional sources and lower than the carbon footprint
of liquefied natural gas (LNG).[198]
E.ON told us that the "emissions when burning [shale gas
or oil] are no different to any other form of gas or oil
transport emissions would be lower when using domestic sources
of gas and oil rather than LNG/oil imports."[199]
110. The MacKay report found that
shale gas would produce a "significantly lower" carbon
footprint when used for electricity generation than coal.[200]
Professor Muller wrote that for the "same energy produced,
carbon (the main component of coal) produces twice the carbon
dioxide that does methane (the main component of natural gas)".[201]
FUGITIVE METHANE
111. Methane itself is also greenhouse
gas. The UK Energy Research Centre note that "methane
can leak from wellheads during the extraction process and during
transportation."[202]
Methane escaping in this way is commonly referred to as 'fugitive
methane'.
LEVEL OF FUGITIVE METHANE EMISSIONS REQUIRED TO NEGATE
BENEFITS OF SHALE GAS OVER COAL
112. WWF, Greenpeace and Friends
of the Earth told us that research from Princeton University suggested
that for shale gas to maintain a lower carbon footprint than coal,
cumulative fugitive methane emissions should not exceed 3.2 per
cent of the gas produced.[203]
Professor Muller disagreed and told us that the 3.2 per cent
figure was "misinformation
based on a simple calculation
you can do that is mistaken
15 per cent to 18 per cent
has to leak before it is as bad as coal."[204]
He referred us to his explanatory article in the New York Times.[205]
Levels of fugitive methane emissions
during shale gas operations
113. Estimates of cumulative fugitive
methane emissions from shale gas production range from 0.4 per
cent to 9 per cent of the gas produced.[206]
WWF, Greenpeace and Friends of the Earth drew attention to studies
from the US which suggest that fugitive emissions are "significantly
higher" than those reported by the industry,[207]
citing research from Cornell University[208]
and the US National Oceanic and Atmospheric Administration (NOAA)[209]
in support. The Frack Free Balcombe Residents Association (FFBRA)
also referred to these studies as "powerful evidence"
that "threatened" the argument that shale gas could
be used as a transitional fuel to a low carbon future.[210]
They added that this US evidence was "completely ignored"
by the MacKay report.[211]
114. The MacKay report acknowledges
that "the current evidence base originates mainly from the
USA"[212] and
analysed the Cornell and NOAA studies. It noted that the calculations
made in the Cornell study had been "strongly criticised"
by other experts, many of whom regard its findings as an outlier.[213]
Professor MacKay's report also noted that the authors of
the NOAA study had acknowledged the difficulties of attributing
their results to an exact source and had pointed out that new
regulations were now in place in the area assessed by the study.[214]
The MacKay report also referred to a more detailed study being
undertaken by the University of Texas (this study was published
after the MacKay report was issued). Professor Muller told
us this Texas study had measured emissions at 190 wells in the
US and the average level of fugitive emissions was found to be
low.[215]
115. Professor MacKay told
us that large fugitive emissions would be "extremely unlikely
to occur in the UK because of the much stronger regulation",[216]
for example, unlike in the US, the venting of methane would not
be permitted in the UK except in an emergency. Mr Egan said
he thought it was recognised in the US that the largest source
of methane emissions was flowback water stored in open pits on
the sites.[217] He
said that this practice would not happen in the UK as flowback
water would be held in a closed tank and taken to an offsite treatment
plant.[218] Dr Grayling
told us that the Environment Agency "would not allow waste
fracking fluids to be stored in open pits or lagoons."[219]
116. Professor MacKay told
us that his report's estimate of the carbon emissions of shale
gas took account of estimates for shale gas emissions based on
US studies.[220] His
report warns that "actual emissions will vary according to
circumstances and that we must be cautious when extrapolating
results."[221]
Professor Robert Mair, University of Cambridge, told us that
"the jury is still out" on the precise quantities of
methane emissions during operations and that careful measurements
of methane escape needed to be made.[222]
Professor MacKay agreed: "We think it is essential that
monitoring and baselining should take place before the substantial
production of shale gas in any location."[223]
The MacKay report recommended a "detailed scientific programme
of methane measurement" that should be independent and managed
jointly between Government and industry.[224]
Sir David King told us that the Environmental Protection
Agency in the US is planning an extensive programme of monitoring
methane emissions.[225]
117. We find persuasive Professor MacKay's
conclusion that the carbon footprint of shale gas, including fugitive
methane emissions, is similar to that of conventional gas production
and substantially less than coal. We endorse the recommendation
in his report for a monitoring programme, jointly managed by the
Government and the industry, to measure the level of fugitive
methane when shale gas extraction begins in the UK.
Compatibility with UK climate
change objectives
UK'S CURRENT COMMITMENTS
118. The Climate Change Act 2008
requires that "the net UK carbon account for the year 2050
is at least 80% lower than the 1990 baseline."[226]
To ensure that regular progress is made towards this target, the
Act established a system of five-yearly carbon budgets.[227]
The Committee on Climate Change was set up by the Act to advise
the Government on the carbon budgets. Four budgets have been announced
to date, the latest covering the period 2023 to 2027. The Committee
on Climate Change has also recommended extensive decarbonisation
of power generation by 2030 to ensure the UK is on track to meet
the 2050 target.[228]
The Government did not include this target in the Energy Act 2013
and Parliament voted against proposed amendments to introduce
it. [229]
COMPATIBILITY OF SHALE GAS DEVELOPMENT WITH CURRENT
COMMITMENTS
119. Mr Molho of WWF-UK told
us that increased reliance on gas infrastructure "risks creating
a breach of our carbon budgets."[230]
He described a "false choice between either burning lots
of shale gas or burning lots of coal, when fundamentally we have
another possibility ahead of us
which is to make a rapid
move towards an efficient and low-carbon energy system."[231]
The UK Energy Research Centre (UKERC) wrote that "significant
amounts of unabated gas-fired generation in the UK power generation
mix in the 2020s and beyond would make it very difficult to comply
with the UK's legally binding carbon targets."[232]
120. Professor Muller told
us that environmental protection activists opposed shale gas development
because "if we have a cheap alternative then there will be
less of an incentive to develop [renewables]."[233]
His answer was that, "if we do not develop natural gas then
it will be coal that will come in."[234]
Mr Cronin said that "the facts are that we will need
low-carbon forms of energy for the future, whether that is wind
or nuclear. They are quite expensive at the moment, and we need
to have a transition. The transition has to be gas".[235]
The renewables industry should not fear shale gas as it "will
give the opportunity for a transition to enable renewable energy
to become cost-competitive."[236]
121. The Minister for Energy told
us that "new gas is consistent with the decarbonisation of
the power sector and it will help us to meet some of these targets."[237]
The Government have set aside £1 billion for commercial development
of carbon capture and storage.[238]
Mr Figueira said that "there will be a continued need
for gas in the decarbonisation efforts
it is potentially
a destination fuel if we can get [carbon capture and storage]
working".[239]
122. Chapter 2 describes the role
of gas in the UK energy's mix.[240]
The recent report of the Committee on Climate Change that recommended
extensive decarbonisation of power generation by 2030 acknowledged
a continuing role for gas: "well regulated production of
shale gas could have economic benefits to the UK, in a manner
consistent with our emissions targets, while reducing our dependence
on imported gas."[241]
PROBLEM OF "LOCK-IN"
123. The Tyndall Centre for Climate
Change feared that a "golden age" of gas might "turn
out to be a gilded cage, locking the UK into a high carbon future."[242]
Professor Dieter Helm disagreed; "lock-in" was
a problem especially associated with coal, "the difference
between gas stations, coal stations, nuclear stations
is
that gas stations are very cheap to build relative to other technologies
and they can be built very quickly. Therefore they can be depreciated
very fast, so you get your economic return back pretty early on
in the cycle".[243]
Mr Rogers said that the "very nature of shale gas militates
against [lock-in]
the wells decline very quickly
the degree of lock-in is not really an issue to be too concerned
about."[244]
124. We consider that development
of shale gas in the UK is compatible with the UK's commitments
to reduce greenhouse gas emissions. There is an acknowledged role
for gas in the UK's energy mix as it moves towards fulfilment
of its commitments. The carbon footprint of home-produced shale
gas would be smaller than that of imported LNG (which needs to
be processed and transported). Substitution of home produced shale
gas for imported LNG should therefore make a positive contribution
to achievement of the UK's commitments on climate change.
194 WWF, Greenpeace and Friends of the Earth. Back
195
Residents Action on Fylde Fracking (RAFF) and Frack Free Balcombe
Residents Association (FFBRA). Back
196
MacKay, D. and Stone, T. (2013) Potential Greenhouse Gas Emissions
Associated with Shale Gas Extraction and Use, DECC, 9 September. Back
197
Ibid. The carbon footprint includes the carbon dioxide
emissions associated with the combustion of shale gas and the
methane that can be released into the atmosphere as a result of
shale gas extraction (known as 'fugitive methane'). Back
198
Ibid. The report found that the carbon footprint of shale
gas extraction and use is likely to be in the range 200-253 g
CO2e per kWh of chemical energy, which makes shale gas's overall
carbon footprint comparable to gas extracted from conventional
sources (199-207 g CO2e/kWh(th)), and lower than the carbon footprint
of Liquefied Natural Gas (233-270g CO2e/kWh(th)). Back
199
E.ON. Back
200
MacKay, D. and Stone, T. (2013), Op. Cit. The report found
that when shale gas is used for electricity generation, its carbon
footprint is likely to be in the range 423-535 g CO2e/kWh(e),
compared to 837-1130g CO2e/kWh(e) for coal. Back
201
Professor Richard Muller. Back
202
UK Energy Research Centre. Back
203
WWF, Greenpeace and Friends of the Earth. Back
204
Q 48. Back
205
Published in a New York Times blog which is available at: http://dotearth.blogs.nytimes.com/2013/08/01/two-climate-analysts-fault-gas-leaks-but-not-as-a-big-warming-threat/?_php=true&_type=blogs&_r=0.
In the New York Times post, Professor Muller refers to an explanatory
paper on his own website which can be found here: http://static.berkeleyearth.org/memos/fugitive-methane-and-greenhouse-warming.pdf
Back
206
Q53 for the 0.4% estimate & see http://www.nature.com/news/methane-leaks-erode-green-credentials-of-natural-gas-1.12123#b1
for the 9% estimate. Back
207
WWF, Greenpeace and Friends of the Earth. Back
208
Howarth, R., Santoro, R. and Ingraffea, A. (2011) 'Methane and
the greenhouse-gas footprint of natural gas from shale formations',
Climactic Change, Volume 106, Issue 4. This study concluded
that between 3.6 per cent and 7.9 per cent of methane from shale
gas production escapes to the atmosphere over the lifetime of
a well. Back
209
See http://www.nature.com/news/methane-leaks-erode-green-credentials-of-natural-gas-1.12123#b1.
The study found that rates of methane leakage from a field in
Utah were 9 per cent. Back
210
Frack Free Balcombe Residents Association. Back
211
Ibid. Back
212
MacKay, D. and Stone, T. (2013), Op. Cit. Back
213
Ibid. Back
214
MacKay, D. and Stone, T. (2013), Op. Cit. Back
215
Q 53. The study reported average leakage of 0.4% of gas produced.
Back
216
Q 209. Back
217
Q 86. Back
218
Ibid. Back
219
Q 167. Back
220
Q 209. Back
221
MacKay, D. and Stone, T. (2013), Op. Cit. Back
222
Q 71. Back
223
Q 209. Back
224
MacKay, D. and Stone, T. (2013), Op. Cit. Back
225
Q 209. Back
226
Climate Change Act 2008, section 1(1). Back
227
Climate Change Act 2008, section 4. Back
228
Committee on Climate Change (2013) 'Next Steps on Electricity
Market Reform'. The report called for legislation in the current
Parliament to set a target to reduce the carbon intensity of power
generation to 50 gCO2 /kWh. The Government said that
the Secretary of State would be allowed to consider a 2030 decarbonisation
target for in 2016. 50 gCO2 /kWh would represent a
90% reduction from the carbon intensity of power generation in
1990. Back
229
HC Deb, 4 June 2013, col 1440; HL Deb, 28 October 2013, col 1368. Back
230
Q 33. Back
231
Q 45. Back
232
UK Energy Research Centre. Back
233
Q 57. Back
234
Ibid. Back
235
Q 62. Back
236
Q 66. Back
237
Q 261. Back
238
Q 266. Back
239
Q 179. Back
240
See from paragraph 5 onwards. Back
241
Committee on Climate Change (2013), Op. Cit. Back
242
Tyndall Centre for Climate Change. Back
243
Q 124. Back
244
Q 133. Back
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