Environmental Engineering Reference
In-Depth Information
long-term decarbonisation of global energy demand is limited. Given a global
target of approximately 90% reduction in CO
2
from fossil-fuel use by 2050 and
net zero CO
2
emissions by 2070, the time frame within which shale gas can be
used unabated is limited.
The third condition (3) for the use of shale gas within a transition pathway
is that it leads ultimately to a lower-carbon energy system. Thus, it should
not divert investment in the research, development and deployment of
energy-demand reduction, renewables, carbon capture and storage, and
nuclear technologies. Currently, however, economic analysis of shale-gas
exploitation in the US suggests its continued development will delay the
economic feasibility of nuclear energy in the USA by one or two decades,
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and similarly, without more stringent climate-change policy in the US, delay
deployment of renewables and carbon capture and storage by up to two
decades.
43
Such delays are significant when set within the context of global
energy scenarios that deliver emissions reductions consistent with avoiding
2 1C warming; these rely on large-scale deployment of these technologies, all
of which in practice take decades to build at such scale.
It is also important to consider the time frames of shale gas exploitation in
considering its role as a transition fuel. Given the lifespan of gas infra-
structure, 30 years for a modern Combined Cycle Gas Turbine (CCGT) power
station for example, the window of opportunity for shale gas as a transition
fuel is time bound. Building new infrastructure post-2020 would run the risk
of it not being used for its full design life and becoming a 'stranded asset'
where ''environmentally unsustainable assets suffer from unanticipated or
premature write-offs, downward revaluations, or are converted to liabil-
ities''.
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In the case of shale gas and, more broadly, fossil-fuel-dependent
infrastructure, this is an area of on-going research, particularly with refer-
ence to investment-fund holders.
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Furthermore, if appropriate energy pol-
icies are not in place, rather than creating stranded assets inconsistent with
a low-carbon future, the continued development of fossil-fuel infrastructure
could lock countries into dependency on fossil fuels, creating higher cost
barriers for alternative energy sources to compete with.
How this plays out in other regions of the world will depend very much on
local markets and governance systems, but it appears that in the only country
where shale gas has been exploited to date, the US, it is thus far not acting as a
transition fuel. Indeed, the IEA reported in their World Energy Outlook sup-
plement ''Are We Entering a Golden Age of Gas?'' (2011)
1
that a high-gas-use
scenario probably would result in 3.5 1Cwarming,wellbeyondwhatisgen-
erally regarded as dangerous climate change. Their Chief Economist, Fatih
Birol, therefore commented that ''We are not saying that it will be a golden age
for humanity - we are saying it will be a golden age for gas''.
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4.2 Future Opportunities?
So what role could shale gas have in a rapidly decarbonising world? For shale
gas to be a true transition fuel, any displaced coal must effectively remain in
