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Tag Archives: carbon sequestration

BECCS: 10% of UK energy & net carbon cuts

By Dave Elliott

Bioenergy use combined with carbon capture and storage (BECCS) can deliver negative emissions, i.e. the net removal of CO2 from the atmosphere, whilst producing energy in the form of electricity, heat, gaseous and liquid fuels, according to the UK Energy Technologies Institute (ETI) in a new study. Some have serious doubts about the cost, viability, impacts and reliability of large scale carbon capture and storage (CCS). Some also see it as a diversion from proper mitigation measures such as renewables and as just a way to allow for continued use of fossil fuels. But some environmentalists are keen on BECCS as a green option that might redeem CCS, if it works. Then again some environmentalists are unhappy with large scale biomass combustion, especially if using imported wood pellets, and so oppose BECCS.


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EGU 2013: climate change hard to reverse

By Liz Kalaugher

It’s early days, but scientists are developing techniques to remove carbon dioxide from the atmosphere, either directly through technologies such as artificial trees or, less directly, by biomass burning with carbon capture and storage. Even if these methods are implemented, however, the Earth will feel the temperature effects of climate change for centuries to come.

That’s according to Andrew MacDougall of Canada’s University of Victoria, who gave a press conference at the European Geosciences Union’s General Assembly in Vienna. His simulations using the University of Victoria Earth-System Climate Model indicate that without any artificial carbon removal, and assuming that fossil fuels run out, around 60–75% of near-surface warming will remain 10,000 years into the future.


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Shale gas and CCS

In the 2012 Budget, Chancellor George Osborne said ‘Gas is cheap, has much less carbon than coal and will be the largest single source of our electricity in the coming years’.

DECC followed this up by saying that it saw gas as ‘continuing to play an important part in the energy mix well into and beyond 2030, while meeting our carbon budgets. We do not expect the role of gas to be restricted to providing back-up to renewables, and in the longer term we see an important role for gas with CCS.’

However then the independent advisory Climate Change Committee (CCC) warned the government that ‘Extensive use of unabated gas-fired capacity (i.e. without carbon capture & storage technology) in 2030 and beyond would be incompatible with meeting legislated carbon budgets’.

DECC backed off a bit, saying that ‘after 2030 we expect that gas will only be used as back up [for variable renewables], or fitted with Carbon Capture and Storage technology.’

There are all sorts of problems with this plan. Firstly, it is far from clear whether, and if so when, CCS technology will be available and widely deployed. What is clear is that it will add substantially to the cost of power generation. Secondly, it is not clear to what extent shale gas will extend the UK’s diminishing gas reserves- and at what price, in both economic and environmental terms, not least given the large amounts of water needed for fraking, the resultant ground water contamination and the risk of micro-quakes from fraking. Thirdly, pushing ahead with CCS and shale gas will deflect resources from the development of renewables, including sources of green gas (see my previous Blog), the only real long term sustainable energy options, unless you see fast breeders or fusion as viable, sustainable options.

All these issues are contentious. The industry say that shale gas fracking is fine, with minimal environmental impacts:

However, the European Commission has published a study on environmental impacts which says that extracting shale gas generally imposes a larger environmental footprint than conventional gas development. Risks of surface and ground water contamination, water resource depletion, air and noise emissions, land take, disturbance to biodiversity and impacts related to traffic are deemed to be high in the case of cumulative projects. On climate impacts, the EU has issued a report which says that shale gas produced in the EU causes more GHG emissions than conventional natural gas produced in the EU, although, if well managed, less than imported gas from outside the EU, whether via pipeline or by LNG, due to the impacts on emissions from long-distance gas transport. [

Some see emissions from shale gas combustion being abated by CCS. However, some environmentalist worry about the impacts and safety of CCS (e.g. the risk of sudden major CO2 release) and about it providing a way for the continued use of fossil fuels at high extra cost, with, in practice, the net emission reductions not actually being as high (80-90%) as is claimed.

The European Environment Agency says that, depending on the CO2 capture technology used, there could be a net rise in some toxic emissions:

Some studies also suggest that CCS might trigger, and be susceptible to, micro-quakes, possibly releasing all the stored CO2 suddenly: and

However, CCS does offer the possibility of carbon negative energy production, if carbon neutral biomass is used as a fuel, so some greens see fossil CCS as an interim test bed for a very positive green CCS option.

Against that, there are the opportunity cost issues both for CCS and shale gas. They both keep fossil fuel going as major option. It does seem that shale gas has already undermined renewables in the USA:

Certainly there has been a boom in shale gas there. The U.S. used to generate about half its electricity from coal, and roughly 20 % from gas. But now coal’s share is 32%, on a par with gas, with shale gas paying an increasing role. There are disputes about net emission from shale gas, but natural gas is about 40% less carbon intense/kWh than coal, and the overall result of the US ‘dash for gas’ is that emission have fallen by 14%, although the expansion of wind power will also have helped. But will shale gas boom continue? Some say the wells will become rapidly depleted:

In the UK, the optimists suggest that shale gas finds so far could be worth up to £50 bn and were equivalent to about a third of conventional UK natural gas reserves- and much more may be found to be available.

A much better option, some say, than importing LNG from Qatar, or expanding coal use. The later is more carbon intense, the former may be unreliable:

So the battle goes on, with a series of reports reviewing the prospects from a range of perspectives, e.g :

On (or rather under) the ground, some shale gas drilling looks set to go ahead in the UK, but although there are plans, as yet there are no major UK CCS projects. There was much vilification about the mess, following the collapse of the earlier CCS programme. Margaret Hodge, chair of the Public Accounts Committee, commented that the government ‘must learn the lessons from this failure to avoid squandering any more time and money’. The National Audit Office published a review of the programme, which said the failed funding round was ‘a high-risk and challenging undertaking launched with insufficient planning and recognition of the commercial risks’. A UKERC report talked of a long hard trek.

The government has launched a new funding programme, with a view to starting commercial operations in the 2020s, using the £1 bn from the shelved CCS programme. The original programme had been about CCS for coal-fired plants, but it has now been expanded to gas plants. That’s maybe just as well. For, with OFGEMs concerns about power shortfalls hitting the headlines, 20GW of new gas-fired plant have been proposed for installation by 2030. Though whether any of this will have CCS remains unclear. As is also how much shale gas there will be to run them on- despite the Chancellors promise of a ‘generous tax regime’.

While shale gas extraction is new in the UK and is being opposed in parts of the rest of the EU, the situation in the USA is somewhat different. As noted above, shale gas fraking is widespread and expanding. CCS is also now beginning to take off there, although in a more limited way. There have been some small CCS projects in Germany and France, but what has been claimed as the word’s first integrated carbon capture system, a demonstration project in Alabama, has began underground injection of CO2 recovered from emissions from a coal-fired power plant.

For an overview of CCS technology and the evolving regulatory situation in the USA, see ‘Carbon Capture and Storage’ G. Morgan and S, Mccoy, Routledge.

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