Carbon Capture. Getting behind the hysteria.

Carbon capture is in the news again, as the new Labour government announces a substantial new programme for the development of the technology. This has attracted a barrage of criticism from both Left and Right, in spite of the fact that carbon capture is widely regarded as an essential component of any mitigation strategy. So it’s worth exploring a bit further.

 

Some technical background.

 

We should get the terminology clear. There are many approaches to carbon capture, including the use of natural processes in the carbon cycle, for example by improved land use, planting trees or through various “geo-engineering” schemes to increase the “fixing” of the carbon in the oceans.  Greens and others, unsurprisingly, tend to favour the most “natural” and least environmentally intrusive of these. 

 

Second, when CO₂ is captured, it can either find a useful purpose, or it can be sent to a safe permanent store. Use in the soft drinks industry will be trivially small, but it can also be used in the production of synthetic fuels. Most recently there has been a lot of interest in synthetic aviation fuel (SAF) for the hard-to-decarbonise aviation industry.

 

Trees are one form of direct atmospheric carbon capture (DACC). But there are also industrial process approaches to direct capture, sometimes referred to as mechanical trees, which rely on established chemical techniques to separate CO₂  from the atmosphere. It’s claimed that the cost of DACC and subsequent storage (DACC+S) could be brought down to below $200/ tonne, a level that could imply total costs of emission-free oil use well within the historical range of oil price variations. Proposed options for storage include geological formations such as depleted oil reservoirs  and the deep oceans

 

Problems with and arguments against the various DACC methods include:

 

·       excessive requirement for land use, sometimes in competition with food production; this will apply to some but not all methods of both a “natural” and industrial nature; this places an upper limit on what they can achieve

·       excessive land use can also have ecological and human rights implications

·       unproven nature and potentially high costs, and, in the case of natural methods, science unknowns around whether particular land-use policies will be net emitters or receivers of CO₂

·       for industrial methods, high energy use requirements

·       the argument that carbon capture is a distraction from the preferred alternative of eliminating fossil fuels

·       in relation to storage, doubts about suitability of locations, safety and permanence; transport of CO₂and injection into storage may also be expensive

 

The above has all been about direct air capture. However it is, for obvious reasons, likely to be much easier and cheaper to capture high concentrations of CO₂  at the point of combustion when it is released from the fossil fuel. A Green version of this technique involves the use of sustainable bio-fuels, known as bio-energy carbon capture and storage or BECCS. BECCS is likely to be severely supply limited in relation to the scale of what is needed. More generally carbon capture can be fitted or retro-fitted to fossil burning plant, including power generation, and this has generally been the main focus of carbon capture and storage policies, usually referred to as CCS.

 

An additional issue for CCS is that it is likely to be less than 100% effective, with a leakage rate of perhaps 10% or more, so it is not a silver bullet.

 

Is carbon capture an essential component of climate strategies?

 

The IPCC is fairly clear that carbon removal, ie DACC, will be an essential component of any feasible route to a sustainable future. It also endorses continued use of fossil fuels, where this is accompanied by CCS, as one of the options for getting to a net zero future. CCS is also supported by the UK Committee on Climate Change (CCC) as part of a UK strategy aimed at this objective. Both these bodies have the advantage of access to a huge body of scientific and technical advice on the subject, in the context of means to mitigate climate change.

 

So should the UK government be promoting CCS?

 

On the basis of IPCC and CCC advice, the principle of promoting CCS seems to bejustified. There may be alternative means of getting to net zero, but if this is the quickest and cheapest option, then there should be no reason to object to it. Moreover this will not just be a UK issue. Much of the world is even more locked into fossil-based technologies than the UK, so the potential of CCS as an interim or transition technology may be quite important.

 

Whether it has a positive contribution to a UK industrial strategy is another question. Potentially the answer is that it does. Countries like Germany have a much higher lock-in to fossil fuel. But as ever, geography and trading relations matter. Not all countries will enjoy the storage options that the UK has, and Brexit will make the potential to exploit European markets harder.

 

Finally there is a history to this. In 2015 the Cameron/ Osborne government cancelled a CCS programme after the spend of £ 100 million of public money and substantial private sector investment of time and resources. This was part of a major rolling back of  Cameron’s Green promises and accompanied the slashing of budgets on other “easy win” measures such as home insulation. As a marker of determination to take net zero seriously, the Labour government's move is a welcome step. But it does not detract from the need to continue to explore the wider DACC options for carbon removal and storage, nationally and globally.

FRACKING WAS NEVER A SENSIBLE CHOICE FOR THE UK.

Perhaps carbon capture was a better bet and one that might have helped justify fracking.

Source: The Independent

The Fantasy of an Economy Transforming Pot of Gold

Perhaps Cameron and Osborne imagined that fracking could be a re-run of the enormous boost that North Sea oil gave to the UK economy of Margaret Thatcher. I recall the late Denis Healey predicting in the late 1970s that whichever party came to power when North Sea oil was about to come on stream would be in power for a generation. And so it proved. Mrs Thatcher came to power in 1979 just before North Sea oil came on stream, adding up to 10% to annual income (GDP) in the 1980s and 1990s. The revenues were even sufficient to finance the disastrous economic policies that resulted in the wholesale deindustrialisation of Britain in the 1980s and 1990s, and even to allow the pretence  that this was all due to successful economic policy.

So it’s easy to understand why the government of Cameron and Osborne should have looked at gas fracking not just as a potentially secure and indigenous source of what is currently still the dominant fuel in the UK economy, but as a macro-economic “get out of jail free” card, to offset some of the economic damage wreaked on the UK and world economies by an out-of-control financial and banking sector in 2008. The very real success of fracking operations in the USA clearly encouraged this idea.

Unfortunately “geography will out” as the government is now belatedly discovering. Sadly this was all too evident at the time. Writing in 2013, and early in the progress of UK fracking initiatives, Howard Rogers of the Oxford Institute for Energy Studies summarised fracking prospects[1] very succinctly as follows

“... the sobering conclusion is that UK shale gas, given its timing and perhaps modest scale in terms of production level, in no way changes the critical and pressing nature of UK policy challenges and decisions needed between now and the end of the decade.”

“Geography” in this case is a combination of geology, which determines a theoretical reserve and likely cost, and population density, which amplifies the problems of secure extraction without serious social and environmental costs. Unlike North Sea oil, the fracking boom was never set to repeat the 1980s oil boom.

The UK government remains muddled and inconsistent over whether or not to continue its support for fracking. It has, according to the recent National Audit Office report on Fracking for shale gas in England, no clear idea on how much it has spent supporting fracking, what the benefits would be and how much investment would be needed in future. Inter alia, the National Audit Office said ministers could also not explain who would pay for clean-ups if fracking companies went out of business.

The National Audit Office (NAO) report highlighted:

• risks of the self-reporting system of shale gas regulation
• unprecedented public opposition to fracking planning applications and falling national support
• slower than predicted development of the industry
• lack of progress on carbon capture usage and storage (CCS) needed for shale gas to meet climate objectives

The Environmental Case ?

The last of these observations, on the failure to progress carbon capture, is perhaps the most telling. Given that we are now targeting zero carbon, natural gas, in principle at least, is likely to be confined to a declining and transitional role[2]. Any environmental defence of further gas exploration was therefore dependent on assurances that it would not add to emissions, with carbon capture being one route to achieving this, at least in part.  It is therefore ironic that the Cameron government should also have pulled the plug on carbon capture for the UK, though only after the private sector had spent several hundred million on it, and at severe cost to the reputation of the UK in terms of its ability to follow through on commitments to energy industry investors.

Carbon capture is by no means an ideal technology, partly because of the energy inputs it requires and partly because it typically fails to capture 100% of CO2, a necessity in a zero carbon world. But at least it may have had more potential as a transitional technology, given the amount of fossil fuel based generation and other capacity that the world currently has.

Lessons to be Learned

This episode is perhaps an excellent illustration of what happens when governments take energy policy decisions not driven by any realistic appraisal of environmental, climate or energy policy needs, but by the impulse to gamble on a quick fix with a macro-economic and political pay-off. Expert opinion was always sceptical, and environmentalist opposition has been more than vindicated.

                                  

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[1] https://www.oxfordenergy.org/wpcms/wp-content/uploads/2013/07/UK-Shale-Gas-GPC1.pdf

[2] There are however possible options for synthesising gas as a means of chemical storage to overcome the seasonal imbalances between renewable generation and winter heating demands. But this is another story.

FINANCIAL SUPPORT FOR ENVIRONMENTALLY SOUND POLICIES IN POORER COUNTRIES MAKES SENSE FOR EVERYONE. THE CASE OF FIREWOOD, CHARCOAL AND DEFORESTATION.

 You tube presentation on this subject available at https://youtu.be/d81oGZzQaQ0

And it’s not just a matter of ethics or moral responsibility.


There is now near universal acceptance that human responsibility for greenhouse gas emissions constitutes possibly the greatest possible economic “externality” of all time, as activities which carry little cost for individual actors will have wider and global consequences that range from the very costly to the potentially catastrophic. Carbon emissions in one place (eg the USA, the UK, or any other country) have a global impact on climate, but, for a variety of reasons, there is currently no consistent or universal way to reflect the resulting climate costs back into individual and national choices and decision making on fuel burning[1]. 

This commentary will deal with one particular example, that of the use of firewood for cooking in rural societies, and the potential for substitution with rural renewable energy (RRE), to illustrate a wider set of principles that need both to be understood and to govern our discourse, particularly in relation to the value of energy sector development aid. Put simply the massive market failure that sits behind climate change should make such support a matter of vital self-interest for the providers of aid in the global community as well as an important resource for the recipients. Ultimately there can even be a financial pay-off.

Firewood is not always carbon neutral

Women carrying firewood| Photo source: Face2FaceAfrica.com

Wood burning is sometimes classed as use of a “biofuel” and regarded as nearly carbon neutral. This may be so, for example, with wood pellet[2] burning at Drax power stations in the UK.  But this neutrality assumes the wood is being harvested in a sustainable way. When the collection of the wood results in deforestation, as is currently the case on a large scale in many parts of the developing world, this biofuel is by no means a sustainable resource. Charcoal or wood burning reduces the carbon store of the forest, and adds substantial incremental CO₂ to the atmosphere; this is in addition to any other damaging consequences that it can and often does pose for a local and regional environment (soil degradation, habitat loss, and flooding risk).

The global or “planetary” benefit of enabling rural communities to reduce firewood consumption


Cost benefit analysis has a number of limitations in relation to assessing climate policy questions, not least being the conceptual and ethical difficulty of comparisons across low and high income economies, and a lack of consensus on even an approximate valuation of carbon emissions. This is compounded by the complexity of estimating both actual firewood or charcoal consumption, on the one hand, and multiple additional environmental consequences, on the other. However, it is possible to at least demonstrate the scale of some of the benefits compared to the costs, and in this instance the exercise provides a powerful message.

The first step is to estimate typical use. The World LP Gas Association estimates that cooking with wood requires typical per capita wood consumption of around 400 kg annually, and that this could be substituted by 36 kg of LPG; this is equivalent to about 500 kWh of electricity. Other sources confirm that this level of wood use for cooking is a very credible estimate. The very large weight difference compared to LPG reflects the much lower energy density of wood compared to LPG, the moisture content of wood, the “heat loss” inefficiency of wood burning, and its lack of controllability.

Assuming a 50% carbon content for the wood, the associated per capita CO₂ emissions[3] will amount to about 730 kg. On the basis of the equivalence assumed above, 1.0 kWh of renewable electricity can substitute for 0.8 kg of wood and hence eliminate 1.47 kg of CO2 emissions.  Bringing electric cooking to 10 million people would on this analysis reduce CO₂ emissions by over 7 million tonnes a year.

Putting a value on carbon emission reduction

Deforestation in the Amazon. The Weather Channel.

The environmental or climate related cost of emissions, or the value of emissions reduction, is the next element in the calculation. Levels of carbon tax, or carbon prices within “cap and trade” regimes, where they exist, have so far failed to provide market valuations of carbon emissions that provide a realistic reflection of the human and environmental cost associated with climate impacts.[4]  More realistic numbers are presented in some Committee on Climate Change scenarios, usually based on estimates of the prices necessary to induce sufficient low carbon investments to achieve targets, ranging up to $ 100 per tonne or more.

Arguably more realistic estimates also stem from the increasing recognition that globally we shall have to move to a “net zero” world and that this, if achievable at all, will very probably require direct removal of carbon from the atmosphere, an extremely expensive operation. Estimates of the current cost of this operation have been put at around $600 per tonne, although some experts claim this might conceivably be reduced to about $ 200 or less.  If this view of the future is adopted, a conservative estimate of the “true” cost of current emissions might be as high as $ 200 per tonne.  Inevitably this cost burden would have to fall disproportionately on countries most able to pay.

These numbers suggest that, if we take the cost of direct extraction as being between $100 and $ 200 per tonne, then every kWh of electricity used in RRE cooking will ultimately result in the global community having to spend between 14 c and 28 c less on removing carbon from the atmosphere, similar to the kWh retail tariff rate in many developed economies. We compare this with estimates of the unit cost of delivered electricity under RRE schemes, for which the World Bank’s ESMAP estimates that the unit cost could fall to $ 0.22/kWh, or 22 c, by 2030.

Of course, the real world is much more complex than this simple comparison suggests. The marginal cost of low load factor cooking load may be significantly higher than our projected average or unit cost of 22 c/kWh. Much of the benefit could be achieved, possibly more cheaply, with LPG[5]. Other economic, social and local infrastructure issues  will be relevant. RRE is only sustainable with a wider range of uses. And the difficulties inherent in implementing successful RRE programmes should not be understated. On the other hand there are multiple benefits that accrue from RRE in terms of economic development, income generation, health, and the local environment, which have not been enumerated above. And there is evidence that RRE households will themselves be able to pay on tariffs that cover most if not all of the total cost. Firewood collection is not free, not least in terms of the time of women[6] and families who may do most of it; nor is charcoal. So electric cooking can provide a win-win both for global environment and for immediate benefit to RRE communities.

Taking a long term and global perspective

This analysis demonstrates that development aid in the energy sector can, ultimately, come close to paying for itself even from a “selfish” donor perspective, and make a major immediate contribution to reducing carbon emissions. In practice aid funds will usually need to provide only a part of the capital finance and very little of the ongoing costs of RRE. Reducing wood burning and deforestation should be a huge priority, as one of the lower cost ways of meeting global targets and avoiding environmental degradation.
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Further comments from readers

One important additional fact is that the rapidly growing use of charcoal amplifies the problem, as it results in even more emissions and deforestation than firewood. This is in large part a result of urbanisation, where firewood is no longer an option for households.

Brian has also pointed out that it is far cheaper to look at green carbon sinks (e.g. planting trees) or avoiding emissions in the first place (i.e. more renewables quicker). so the economic tradeoff for a green investor isn't as simple as direct air capture vs eliminating firewood.

The counter, though, is that almost all the alternatives are supply limited in one way or another - green carbon sinks are constrained by the availability of land for example. If those constraints are reached then the marginal cost of CO2 removal becomes the most expensive direct extraction technology. It is of course far cheaper to replace firewood with electric cooking, or even more so for charcoal, and that is the key point. Unfortunately that seems unlikely to be enough on its own.

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[1] The Clean Development Mechanism, defined in the 2007 Kyoto protocol, has been one such scheme, created with the intention of providing wealthier but high carbon economies with a means to reduce emissions by supporting low carbon initiatives outside their own borders, particularly where this would be more cost-effective.

[2] Drax uses imported wood pellets from sustainable sources, although this claim is sometimes disputed.

[3] 1.0 tonnes of carbon translates to 3.67 tonnes of CO₂

[4] The EU emissions price is currently around 25-30 euros per tonne, after many years languishing in single figures, according to Sandbag data

[5] If this were so then LPG might be considered as a “second best” option, for a transitional period, if it were demonstrably capable of more rapid deployment.

[6] One of the notorious weaknesses of cost benefit analysis is that it struggles with non-monetised or only partially monetised activities and economies. This is often particularly relevant to matters affecting the role of women in certain societies..