Everything you wanted to know about CCS (but were afraid to ask)
- 06 Jul 2012, 16:00
- Chris Peters
Carbon capture and storage (CCS) hit the headlines again this
week as
the world's first CCS leakage experiment , running off the
coast of Scotland released its results. Meanwhile, you may have
heard the news that plans for a
new coal-fired power station with a test CCS system in Ayrshire has
been abandoned .
But what is CCS? And why should you care?
What is CCS?
At its most basic, CCS does exactly what it says on the tin -
technology to capture carbon emissions, and store them. In theory,
this means carbon that would otherwise be emitted into the
atmosphere can be locked up somewhere else - without the
climate-altering effects.
CCS is a geoengineering
technique, and ultimately it has been suggested that carbon
capture could be used to
grab carbon dioxide directly out of the air - so-called 'direct
capture'. At the moment air capture is just a distant dream at
anything other than the very small (and very expensive)
scale.
The form of CCS that's most familiar is related to fossil power
stations. Installed on power plant, the idea is that the technology
will capture the carbon emissions directly from the source.
Or at least that's the plan.
Source: UK
Carbon Capture and Storage Research Centre
Why aren't we doing this everywhere?
Unfortunately, at a commercial scale - large-scale deployment at a
reasonable cost - CCS is still a long way off.
That said, there is a lot of research on the go. The new UK CCS research centre ,
funded by Research Councils UK and the Department of Energy and
Climate Change (DECC), aims to "provide a national focal point for
CCS research and development". At present there are only four
commercial scale CCS projects in operation and none of these
are on fuel burning power plant.
Norway recently opened the world's
largest and most advanced laboratory for testing carbon capture
technologies. And one Chinese CCS plant is using the
captured carbon dioxide for fizzy pop.
Scottish CCS has produced
a map tracking all CCS projects across the globe. It's clear
there's a fair few pilots and planned projects out there, but not
many operational project yet.
How expensive is it going to be?
Estimates for the cost of CCS are pretty varied, which is to be
expected for a technology that isn't quite there yet. The
Intergovernmental Panel on Climate Change (IPCC)'s special report
on CCS suggests that capture will constitute the biggest cost.
In total, CCS could add 50 - 100 per cent to coal energy costs and
between 33 and 60 per cent extra for natural gas.
The
British Geological Survey (BGS) suggests the increased cost of
electricity from a new power plant due to CCS would be 21-91 per
cent, and retrofitting older power plant would be even more
expensive.
The US Department of Energy
pulled the plug on plans for a CCS power plant in Illinois
after the price tag rose to $1.8 billion.
Is storing carbon safe?
In the UK, the Natural Environment Research Council is funding an
experiment in Scotland, led by the Plymouth Marine Laboratory,
investigating the potential
impact of a breached carbon dioxide storage tank on the marine
ecosystem.
So far, four and a half tonnes of carbon dioxide have been pumped
into the seabed to simulate a gas leak and according to the
experiment's co-ordinator, Dr Henrik Stahl, there could be both
"winners and losers" - sea urchins seemed to react negatively while
crabs were attracted or unaffected by the bubbles.
The
very latest research, from a group of geophysicists at Stanford
University, suggests that storing carbon underground could, in many
areas, create a buildup of pressure large enough to break the
reservoirs seals,
releasing the stored carbon dioxide. These pressure buildups
could also cause seismic activity, leading the author, Mark Zoback
to wonder whether the cost and risk are really worth it.
So is there still some way to go?
Indeed, and it has
been suggested that global confidence in CCS is waning, perhaps
for lack of political will as well as regulation needed to pilot
and roll out new technologies.
Yet while the diagnosis doesn't seem too good, CCS is a big part
of many influential plans for how on Earth we
might cut global emissions. The IEA
(International Energy Agency) considers CCS an important part of
any low cost greenhouse gas mitigation portfolio, and says without
it, overall costs to reduce emissions to 2005 levels by 2050 would
increase by 70 per cent. The IEA envisions 100 projects globally by
2020 and over 3000 projects by 2050.
Nick Otter, chief executive of the Global CCS Institute reckons
there are a few bridges to cross but remains confident that the
2020 time frame the IEA outlines can still be achieved, although he
warns:
"CCS is not the silver bullet, but
it's a key element..."
Not everyone is optimistic. Doug Parr, chief scientist and
policy director for Greenpeace UK, reckons the UK is pinning too
many hopes on CCS research making a breakthrough, pointing out that
our "energy policy becomes dependent on a technology which hasn't
been demonstrated yet - what's plan B?".
What is the UK doing about CCS?
In April this year, the UK government launched a £1 billion "
CCS Commercialisation Programme" competition to build Europe's
largest 'clean coal' power station.
The competition closed earlier this week and according to a
DECC spokesperson, it's seen "
significant interest from industry".
This is government's
second attempt at boosting CCS innovation. In 2007 the first
competition was launched and
then re-jigged in a move that disqualified some bidders.
Scottish Power, the eventual winners, subsequently abandoned the
project. Chief corporate officer Keith Anderson said
"the bill would have been £1.5 billion" .
Alongside the commercialisation competition, the
UK government is also funding CCS research and development to
the tune of £125 million over four years. Although it's peanuts
compared to the US government's
$3.4 billion stimulus package for fossil fuel research and
development, much of which will finance industrial CCS
projects.
And what's the current UK legislation on
CCS?
At present, new coal power plant must fit CCS, but gas power plant
isn't covered by the same rules. But several commentators have said
CCS has to apply to gas soon, including Environment
Agency head Lord Smith and the Committee
on Climate Change . Likewise, Tim Yeo, chair of the energy and
climate change select committee said the energy bill
must set a clear "twilight" on gas-fired power generation
.
It seems there's not a great deal of agreement between what the
government is planning to do with CCS, what others think should be
done, and what is realistic in terms of the technology.
So is the carbon dioxide storage tank half full or half empty?
Well, there aren't any - not on working power plant anyway.