Carbon capture and storage is not coming to the rescue

My Times column on carbon capture:



Carbon dioxide is not the most urgent problem
facing humanity, compared with war, extremism, poverty and disease.
But most presidents, popes and film stars think it is, so I must be
wrong. For the purposes of this article let’s assume they are
right. What’s the best way of solving the problem?



Whichever party wins the election will be legally committed to
cutting our carbon dioxide emissions by 80 per cent by 2050. About
90 per cent of Britain’s total energy still comes from fossil fuels
and bio-energy, both of which produce carbon dioxide. The expansion
of nuclear, wind and solar is not going nearly fast enough, because
electricity comprises just one third of our energy use. If we are
to decarbonise transport and heating too, we will have to switch to
electric cars, and electric radiators, which means generating three
times as much electricity. Only aeroplanes would be left using
fossil fuels.



Leave aside for now the problem of the intermittency of
renewables: how to charge your car, or cook on your electric hob
when the wind is not blowing and the sun is not shining. Also, the
rest of the world is not following suit: fossil fuel use is growing
rapidly and maintaining market share. The concentration of carbon
dioxide in the atmosphere, as measured on a Hawaiian mountain top,
is climbing relentlessly.



The science and technology committee of the House of Lords (on
which I sit) told the government last week in a report on the resilience of the electricity
system
that it has not sufficiently informed the public about
the “trilemma” facing policymakers. We cannot — in the present
state of technology — make the electricity supply low-carbon,
resilient and low-cost all at the same time. Decarbonisation is not
achievable if politicians wish to restrain energy prices.



Which leaves plan B: to continue using fossil fuels but extract
the carbon dioxide from power station exhaust by “carbon capture
and storage” (CCS). The Energy Technology Institute told our
committee that CCS is the only way to keep the cost of
decarbonisation from raising energy prices by an extra £10 billion
a year by 2030 and “several tens of billions a year” by 2050.



When the topic of CCS comes up, I admit to being unsure whom to
believe. On the one hand there are those who say: it is ready to
go, it solves the problem, what are we waiting for? On the other,
those who say it’s a costly white elephant going nowhere.



My own self-interest as a landlord of a Northumbrian coal
producer would suggest that I should be in the first category,
because it’s a get-out-of-jail-free card for the fossil-fuel
industry. If CCS were to work, then we could press ahead with
fossil fuels and stop worrying. But I’m not convinced it will do
the trick.



It is technically possible to extract CO2 from an exhaust
stream. The recipe is as follows: bubble the exhaust gases
through a caustic brew of chemicals called amines, which grab the
CO2. Then place the brew back on the stove, bring the heat up to
120C and the CO2 fizzes back off again. Capture it and inject
safely into an oil well to enhance the recovery of more oil, or
store it underground. Save the caustic brew and re-use.



The first problem is that the process reduces the efficiency of
the power station. A normal coal-fired power station runs at about
35 per cent efficiency — that is to say, a bit more than a third of
the heat energy in the steam gets turned into electricity. Adding
CCS means that the efficiency drops to maybe 26 per
cent. The cost correspondingly goes up substantially, as do
people’s electricity bills: according to the industry, it would
roughly treble the price to about the same as power from an
offshore wind farm.



The biggest working demonstration of CCS began operating last
October in Saskatchewan in Canada, where SaskPower says its new
coal-fired plant is exceeding expectations, generating about
160 megawatts, 40 of which are used to capture the carbon dioxide,
leaving about 120 megawatts for the grid. The 2,300 tonnes a day of
captured carbon dioxide are 99 per cent pure and are used to
enhance recovery of oil near by. But this is a small unit by
coal-fired power station standards and only pays because the nearby
oil industry is prepared to buy the CO2.



Nor is it without risks, so the greens are against it, though
they would be anyway because they hate the idea of fossil fuels
getting a new lease of life. Injecting huge quantities of carbon
dioxide into the ground risks causing small earthquakes, and
possible leakage, with the (remote) potential to suffocate a nearby
town.



The British government has been dangling a £1 billion carrot in
front of the energy industry to get CCS going. A few years ago, Eon
and Scottish Power both dropped out. Then last year two projects
signed contracts, one in Yorkshire, and one in Peterhead in
Scotland. In the latter case, SSE, the energy company, and Shell propose to pump the CO2 out under the North
Sea, not to help to enhance the recovery of oil but to justify
putting off the decommissioning of an oil platform called
Goldeneye.



Similar delays and cancellations are affecting CCS around the
world. Whereas the United Nations once forecast that at least 20
large-scale demonstration plants would be on line by 2020, in
practice there will be none. Given that electricity is
only a small part of the energy system, if CCS is to solve our
problems it has to roll out to not just every coal and gas power
station on the planet, but to three times as many — once we have
electrified heat and transport.



However, all is not lost. Last week scientists at the University
of California, Berkeley, announced the discovery of a new class of
compounds that scrub carbon dioxide from exhaust much more cheaply.
Called diamine-appended metal-organic-frameworks, they require only
half as much heating as the conventional process. Another team at
Lawrence Livermore Laboratory, also in California, is getting good results with microcapsules of
baking soda. In other words, it is possible that chemists will come
up with something much cheaper — but it will take time to find out
if such ideas can be scaled up efficiently.



For now, though, there is no way to meet our self-imposed
decarbonisation target without bankrupting the country. It’s not
more effort and political will we need; it’s more research.

 •  0 comments  •  flag
Share on Twitter
Published on March 28, 2015 09:23
No comments have been added yet.


Matt Ridley's Blog

Matt Ridley
Matt Ridley isn't a Goodreads Author (yet), but they do have a blog, so here are some recent posts imported from their feed.
Follow Matt Ridley's blog with rss.