Carbon capture: Planet saver or dangerous distraction?
A flurry of carbon capture and storage (CCS)-related announcements was capped on Monday with news that the UK Government will spend £4m to investigate the feasibility of building the UK's first CCS plant. But is this the right avenue to go down?
Supporters of CCS technology claim it will decarbonise energy production and heavy industry in the cheapest possible manner, while opponets fear it detracts from truly clean energy.
With the technology advancing and the debate raging on, here is everything you need to know about CCS, and what it means for the planet and the global economy.
What is CCS?
CO2 is removed from power plants and other large industrial facilities via a chemical process. The captured CO2 is generally compressed to a liquid-like state and transported, mainly through pipelines to storage in deep geologic formations at depths greater than 800 meters.
The peculiarities of the debate over CCS are evidenced by its supporters: a unlikely group including the Green Alliance, the Intergovernmental Panel on Climate Change and oil giant Shell.
The issue is complicated further by technological uncertainty; there is no history of CCS working on the industrial scale required for it to make an impact on climate change.
There are approximately 22 small projects currently under construction or in operation around the world but further development will likely require political and sectoral support. Unlike renewables, there is no output to sell, making commercialisation difficult.
Until the EU ETS is tightened up, or a global price on carbon is agreed at Paris 2015, global adoption of CCS could remain snail-paced.
Who is making the case for CCS and why?
The UK Government has called CCS the "only credible technology to decarbonise some energy intensive industries such as steel and cement". It has invested millions in feasibility studies and argues that, without CCS in the UK, decarbonising the energy system would be up to £40bn more expensive per year.
The International Energy Agency (IEA) agrees, stating that CCS could reduce global carbon dioxide emissions by 19%, and also references the potential economic benefits of CCS.
Essentially it is 'cheaper', because it allows nations and industries to keep producing goods in a manner that would otherwise contribute to global warming.
As Shell's Global CCS portfolio manager put it: "With CCS in the mix, we can decarbonise in a cost-effective manner and still continue to produce, to some extent, our fossil fuels. You don't need to divest in fossil fuels, you need to decarbonise them."
But while CCS may be the cheapest way of decarbonising, the bill still runs into the billions thanks to the complicated technologies and infrastructure involved. The proposed White Rose CCS plant in the Humber - one of two potential UK projects - could cost upwards of £5bn.
Going forward, both the ETI and the Green Alliance argue that 'clusters' of CCS are the most efficient method of carbon capture. For example, while a Humberside CCS cluster could cost around £20bn, it would reduce the cost per tonne of CO2 captured by two thirds, while being nine times more effective.
The ETI also suggests combining CCS plants with biomass facilities and 'short rotation' crops, to deliver negative emissions.
With Government and industry support in scaling up production and sharing costs, CCS technology could store around 50 million tonnes of CO2 emissions a year as soon as 2030.
Who opposes CCS and why?
A statement from Greenpeace, WWF and Friends of the Earth described the use of CCS in the UK as a "dangerous distraction".
"CCS technology has not yet been proven at scale on an integrated power plant and it may prove not to be technically or economically feasible," the statement reads. "Building "capture ready" stations now would therefore impose unacceptable risks both to the climate and to the taxpayer, who may well be trapped into footing the bill for any future CCS retrofit."
In an exclusive interview with edie last week, Green Party MP Caroline Lucas echoed that sentiment. She said: "I worry about CCS in Europe because I think that essentially it will delay the transition that we need to make to a sustainable energy source.
"With CCS you're still not clear about leakage issues, or even the technology itself, it has still yet to be properly proved. I would prefer to see resources going into tried and tested green energy sources. Let's get them up to commercial speed rather than necessarily hoping that CCS will dig us out of a problem."
Lucas's view is shared by much of the public, of whom less than a quarter support CCS. For comparison, 80% support renewables. Similarly a majority of edie readers agreed that CCS "encourage the use of fossil fuels and delays a switch to truly 'clean' energy".
What else should be considered?
Even imagining that CCS could be successfully scaled, emissions savings may be less than predicted thanks to the carbon embodied in the manufacture of compressors, chemicals required to capture the CO2, and the reinforced steel pipelines needed to transport the CO2 to suitable geological structures.
The CCS technology needs to be powered, meaning CCS-equipped plants could use 24-40% more fuel for the same amount of final energy output. This could increase emissions of other greenhouse gases such as methane.
Finally, there is concern about the availability and accessibility of geological formations to pump millions of tonnes of CO2 into, and the environmental impact of such an activity.
Have your say: Readers' poll
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