‘Carbon capture and storage
(CCS) is the only technology able to deliver significant emissions reductions
from the use of fossil fuels’. So said the International
Energy Agency in a report last year. It went on ‘CCS can reduce emissions not only from power generation, but also from
industrial sectors such as iron and steel, refining, petrochemical, and cement
manufacturing.’ According to its
modeling, ‘CCS could deliver 13% of the
cumulative emissions reductions needed by 2050 to limit the global increase in
temperature to 2°C (IEA 2DS). This represents the capture and storage of around
6 billion tonnes (Bt) of CO2 emissions per year in 2050, nearly triple India’s
energy sector emissions today.’ It adds ‘Half
of this captured CO2 in the 2DS would come from industrial sectors, where there
are currently limited or no alternatives for achieving deep emission
reductions. While there are alternatives
to CCS in power generation, delaying or abandoning CCS in the sector would
increase the investment required by 40% or more in the 2DS, and may place
untenable and unrealistic demands on other low emission technology options.’
www.iea.org/publications/freepublications/publication/carbon-capture-and-storagethe-solution-for-deep-emissions-reductions.html
While
some see CCS as just a way to allow fossil fuels to still be used, the IEA says
‘a 2oC pathway represents a
significant departure from “business-as usual” for fossil fuels. Coal use in
power generation falls to around one-third of current levels.’ However, it is still used, but emissions
are reduced since 95% of coal-fired generators are equipped with CCS. It adds ‘40% of gas-fired power generation will also
need to be equipped with CCS in 2050.’ It says ‘this has implications for decisions to invest in fossil fuel-based
power generation and industrial facilities today, as most of these large
capital investments are based on assumed lifetimes of several decades – 30 to
40 years for a power plant. Retrofitting of CCS would prolong the economic life
of these assets and provide a form of insurance against asset stranding. China
alone has an installed capacity of around 860 gigawatts (GW) of coal-fired
power, and IEA analysis suggests that more than one-third of this fleet could
be candidates for CCS retrofit.’
Is
that really what we want- to make fossil fuel use viable long term? Is it
actually possible technically? The IEA say yes on both counts and reports on
some existing CCS projects. In addition to various Enhanced Oil Recovery CO2
injection project it says ‘the global
portfolio of CCS projects now includes the Boundary Dam Project in
Saskatchewan, Canada, which in October 2014 became the first operating
coal-fired power plant to apply CCS. Two additional projects in the power
sector, the Kemper County project in Mississippi and the Petra Nova Carbon
Capture Project in Texas, are due to come into operation in 2016. The Shell
Quest CCS project, launched in November 2015, is the world’s first CCS project
to reduce emissions from oil sands upgrading’. And more are planned. It
concludes ‘Boosting the number of
large-scale projects under development is a priority. These projects are
critically important in providing commercial experience, enabling key
technologies to be refined and cost reductions to be achieved’. Convinced?
Well the UK government wasn’t: it scrapped the UK’s £1bn CCS competition.
The IEA however see CCS as ‘an essential part of the climate solution’.
It claims that‘ a 2-degree pathway
requires deployment of CCS in both industrial and power applications’ and
notes that CCS is already a reality: ‘there
are currently 15 large-scale CCS projects operating throughout the world, with
7 more expected to come online by 2018’.
It also claims that ‘CCS could be competitive with other
dispatchable, low-emission generation technologies by 2030’, citing
Concentrated Solar Power (CSP) as an example.
Moreover, CCS ‘is not just a coal
technology. It is needed to reduce emissions from a range of applications,
including steel and cement manufacturing’. And via BECCS, with biomass used
as a fuel and the emissions captured, it can be carbon negative. All of this
slowing climate change. Quite a sales pitch!
The economic case seems a
little week. All sorts of green energy options might be viable by 2030, not
just CSP, and many already are. The issue is whether it’s worth pursuing CCS
now. And the case for that seems to rest on the belief that renewables can’t or
won’t deliver to scale and in time, with progress being slow due to resistance
to change. So lets start digging! But can we really bury all the emissions we
will continue to produce safety forever?
Will that be any easier than getting renewables going fully? If governments and companies, or the public,
are not willing to push ahead with renewable fast enough for whatever reason,
will they be any more inclined to support CCS? Or is it just that the fossil fuel
lobby wants it, given that it has so much invested in fossil energy- and is
very powerful. And if that slows the development of renewables, then from its
perspective, that’s just too bad, but BECCS is dangled as a long-shot
consolation.
Pragmatically, a bit of CCS
for difficult-to-deal-with industrial processes, and maybe BECCS, may be
helpful, but bulk CCS for power generation seems a risky, inelegant technical
fix, stuffing CO2 into strata deep underground in the hope it will stay there
forever. While potentially delaying the
switch over to renewables.
CCS is not the only
large-scale geoengineering option that’s been proposed. Some are even more
fanciful and potentially risky: seeding the oceans with ferric compounds to
absorb GHG, putting aerosols particles in the high atmosphere to reduce solar
input. Here’s an overview: www.sciencedirect.com/science/article/pii/S1364032113008460
Slightly more credible within
this wide range of ideas is direct air capture of CO2: https://absuploads.aps.org/presentation.cfm?pid=11396
And maybe photo-catalytical conversion
of other GHGs and pollutants. See: www.sciencedirect.com/science/article/pii/S1389556711000281 There is also a range of mega solar ideas, including
mile high solar chimneys with solar heat updrafts from a vast solar greenhouses
driving wind devices mounted inside the towers: www.sciencedirect.com/science/article/pii/S1364032110001292
and more recently: www.sciencedirect.com/science/article/pii/S0038092X14003284
and www.scientific.net/AMM.283.57
That may be a bit more credible and does
avoid having to store wastes somewhere. But it still sounds like a long shot,
compared to conventional renewables. Towers a mile or more high seem to be a little
extreme. Just like digging deep into the earth.
Re-afforestation and changed
farming practices seem more likely to be successful (and cheaper) for
large-scale carbon capture/retention than major geoengineering projects and
also easier than giant solar projects. But these less aggressive sequestration
approaches can only go so far. Most agree that the real answer is the more
fundamental approach of reducing CO2 emissions at source by switching to
renewables. The claim that they will not be developed fast enough and so there
is an urgent need for new approaches to dealing with climate change, may lead
some to back large-scale geoengineering and CCS as desperate measures. Some say
we must accept the risks and ensure we have the full range of options
available. In his recent book ‘Systems Thinking for Geoengineering Policy’, OU
academic Robert Chris
argues that we should promote approaches to dealing with climate change that
are ‘robust against the widest range of
plausible futures, rather than optimal only for the most likely’. Well
maybe, options should not be foreclosed, but surely we should focus on
renewables as the best option: www.tandf.net/books/details/9781138841178/
