Tuesday, December 31, 2019


The Carbon Footprint of Personal Travel

News item. Tuesday 14th January. The government has decided to use public money to support Flybe. More disturbing than casual use of public funds to support failing business is the announcement of intention to review air passenger duty. As we argue below failure to tax aviation fuel is a distortion of the market in favour of the highest emissions forms of transport - another subsidy from an environmentally challenged future to a self-indulgent present. Air passenger duty represented a small step towards redressing the balance and encouraging transport modes with lower emissions. Flybe is a major operator of UK domestic routes where there are more rail and road alternatives.

Most readers of this blog are increasingly environmentally conscious, particularly in relation to climate change. 
Transport may not be the largest source of greenhouse gas emissions, but it is still a major contributor and in some respects one of the most difficult sectors to convert to low carbon alternatives. It also, in many instances, offers a lot of personal choice. So it is a worthwhile exercise to compare the environmental costs of the choices we, individually, make. The calculation can be complicated, but some very interesting ideas arise in the process of making the comparisons. My example will be the choice that a traveller to the South of France might face, assuming a 1250 mile or 2000 km return journey. These may represent very different experiences but for many people this is a real choice. The BBC recently published comparative tables, as shown below.

These numbers are realistic, at least as broad averages, and align quite closely to statistics quoted by other sources. But there are a number of qualifications and observations that can be made.

·         Numbers are invariably quoted for “average” or typical flights, average aircraft or cars, and car journeys including urban driving, and are not necessarily accurate for any particular journey, aircraft, or road vehicle. This analysis also ignores the carbon footprint associated with the manufacture of the cars, trains, buses or planes.

·         For the purposes of a simple comparison, we should disregard the “marginality” argument, that if there are spare seats on any form of public transport, then an individual decision to use that mode of transport has near zero energy and environmental impact. This is technically correct but the argument tells us little about the reality of transport investment choices or what makes sense in policy terms.

·         Airline flights carry an additional penalty in non-CO2 emissions, according to the BEIS data. However the weighting of different GHG in terms of impact is itself a complex issue. But this clearly a major factor.

·         The occupancy rate is crucial for all modes of transport. The implicit and broadly justified assumption for air travel is that typical flights are usually full.  Trains and buses tend to be more lightly loaded. The carbon footprint per passenger mile for the car depends on the number of passengers in addition to the driver. Two in the car halves the footprint as a first approximation.

·         For the car the assumed average is the overall driving average in all conditions including urban and secondary roads. For a typical long journey, on trunk roads and French autoroutes with minimal congestion, and observing or staying a little below the speed limits, one should expect a typical modern diesel car to produce emissions much closer to 130g per km, as compared to the quoted 171g.

·         The other critical assumption is the fuel source for electricity generation (in the case of the train). However the calculation should relate to the incremental power generation induced by the mode of transport, not necessarily the average fuel input per kWh. This would considerably reduce the apparent advantage of the French railways, if incremental load is generated from fossil fuels.

·         The table does not include electric vehicles. If it did  the same question would apply – of dependence on how the electricity is generated. On the basis of current UK sources of generation this suggests a CO2 footprint of about 80g per km for small EVs, as compared to 171g per km for average petrol/diesel vehicles (driver only in each case).[1]

If electricity production can be made carbon-free then the ideal is any mode of transport that is electricity based. This simply reflects the now widely accepted view that the path to decarbonising transport rests on the decarbonisation of electricity followed by the penetration of electricity into the transport market.

And the environment friendly choice between flight and a conventional car journey?

If the individual has a petrol or diesel car, and the choice is between car and air travel, then, purely in terms of CO2, the choice is finely balanced for a single occupancy car as against a flight. However the inclusion of non-CO2 impacts shifts the balance decisively in favour of the car. Additional passengers have an even greater  effect, with two people in the car halving its emissions[2]. The flight is associated with emissions equivalent to 254g per passenger mile, and the car journey with only 65g per passenger mile. For a family of four on my hypothetical return journey of 2000 km, the carbon footprint is approximately 2.0 tonnes for the flight, but only 0.5 tonnes for the car journey.

So purely on an environmental perspective, the preference should be clear.

Current policies discriminate in favour of air travel and against the car

Of course there are several factors that can determine choice of travel mode, including convenience – which strongly favours flying, but in a world that clearly requires progress towards low or zero emissions, one might expect that the costs and prices of the alternatives would at least  reflect the huge additional environmental cost of flying. But this is not the case.

Car drivers pay very substantial fuel taxes, while aviation fuel is tax-free, and it takes little effort to work out that in many instances flying will be cheaper than driving. Advance booking for a flight from London to Nice, for example, can cost as little as £100 return fare. This is a perverse incentive, and continues to be responsible for a very substantial environmental cost, which I have previously argued could be valued at a sequestration cost [3]  of at least £75, will fall heavily on an increasingly near future.

The cost of cheap air travel

Cheap air travel has brought great and welcome opportunities for mass market leisure travel, but its cost has been so low that it has also hugely expanded the volume of travel and significantly changed lifestyles. Wealthy British families can routinely travel to their second homes in France for a weekend. Others routinely commute weekly by air between work in one European city and home in another. And young men from London organise stag weekends in Las Vegas.

Failure to reach international agreement on the taxation of aviation fuel has in consequence resulted in a subsidy from an environmentally challenging future to what some might see as a self-indulgent present. 
Time to find a sustainable solution? Electric aircraft are starting to look like a credible option, at least for short-haul. Otherwise it will have to be synthetic fuels (from an electric route) with a limited amount of sustainable biomass.

[1] The difference is largely attributable to the substantial proportion of low carbon generation in the UK.
[2] In fact extra passengers have a small effect on fuel consumption, so this is a small but not very significant exaggeration.
[3] I have previously suggested a figure of $200 per tonne to represent a minimal realistic cost of future carbon extraction from the atmosphere.

Friday, December 20, 2019


Many people will be disappointed at the lack of success for the parties most committed, at least in their manifestos, to action on climate change. There have been close associations in right-wing economics and politics between Brexit-support, free market fundamentalism and ideologically driven climate science denial,. This is exemplified by politicians such as Lawson, Redwood, Trump and Rees Mogg, as well as bodies such as the Institute for Economic Affairs and the “Economists for Brexit”. Many will fear for the future of a rational approach to climate issues.  But in reality the difference in outcomes, though significant, could be less profound.

TV climate debate with missing party leaders represented by melting ice.

The starting point will be policies for trade.

Climate issues, although seen as the major challenge of our time by most people, barely featured in the election campaign. For the Tories, the issue would have led back directly to trade and Trump, and for Labour, similarly, to the Brexit debate. These were subjects that the main parties, for different reasons, were desperate to avoid. But the links between trade and climate will in due course become very strong. So I make no apologies for deviating briefly from my core themes of energy policy and climate, and addressing the politics of trade policy. I believe these connections will feature increasingly in international negotiations over both trade issues and emissions targets. 

The central issue for a Tory party interested in its own long term prospects, and living up to the promises made to its new constituencies in the North of England, returns once again to the nature of the UK’s relationship with Europe. The rational analysis initially assumed by most commentators was that three main pressures would operate work to keep the UK close to the EU on trade - ie minimal divergence from single market and customs union.

These were that:
·         major shifts in relations with the EU would provide further ammunition to the SNP arguments for an independent Scotland
·         that similar concerns would arise in relation to Northern Ireland, with the added complications of the border in the Irish Sea, the commitments of the Good Friday Agreement, and continuing security dangers
·       economic concern to minimise short and medium term damage to the economy which, as well hitting Northern industrial towns particularly hard, could compromise government finances, and its ability to pay for NHS funding, infrastructure, and regeneration policies implicit or explicit in the campaign

The danger of regression to climate science denial, never too far away with the more intellectually challenged elements of the Cabinet, is of course present if the government wants a trade deal with the Trump administration, but climate issues are more likely to push us closer to Europe both diplomatically and, ultimately, on trade.  Major deals with the US are unlikely. For various reasons, such as the fact that many of our demands would have to be negotiated state by state, they have little or nothing attractive to offer us in return, while their demands on pharma and agriculture should be deeply unattractive to any British government.

Although current headlines suggest that the government may be set on an extreme “hard” no-deal Brexit, Martin Sandbu has pointed out that, based on past experience, we might expect some “creativity”, not to say pretence, as we move through 2020. “In 2019, Johnson declared victory by conceding more than May while claiming he had not.” (FT, 19th December 2019, The End of the Beginning for Brexit.)

We might expect more of the same, the illusion of as “taking back control” while avoiding the economic disruptions that will carry a high political cost, rejection of a formal extension of the transition period in which nothing changes, while still making sure that in reality nothing does change. One option floated by Sandbu is “… a trade treaty with two parts: a bare-bones trade agreement that avoids any tariffs or quotas, plus a “placeholder” agreement that says negotiations will continue on more ambitious trade relations and keeps everything (including the UK’s financial and legal obligations to the EU) more or less the same for as long as those talks continue.” In other words another pretence.

Meanwhile climate issues are not going to disappear, with a steady stream of temperature records and more volatile weather patterns, like those we have seen most recently in Australia. The issues will become more and more important for younger voters, upon whom future governments will increasingly depend, and where the current government has polled particularly badly.

Friday, November 29, 2019


Because that would mean confronting other difficult issues too.

Positive policies also bring with them more inconvenient truths. With climate, policies threaten entrenched ideologies[1]. Politicians are reluctant to talk honestly about costs at election time. But the biggest silence is around the fundamental implications for trade of any realistic global climate regime, and trade remains at the centre of the Brexit dilemma. 
It was widely supposed, only a few months ago, that climate change would be a major feature in the next UK election. This year has seen growing public concern over the threat of climate change as the most important challenge our society has to face. An eight country poll[2] revealed widespread alarm that the crisis is on the brink of spinning out of control, with 64% in the UK agreeing that “time is running out to save the planet”.  At least three-quarters of the public think there is a “climate emergency”, and of climate breakdown risk as “extremely dangerous”.
Climate breakdown was viewed as the most important issue facing the world, ahead of migration, terrorism and the global economy, in seven out of the eight countries surveyed. Only in the US did it come third, behind terrorism and (understandably given the US dismal ranking in international health comparisons) affordable healthcare. An overwhelming majority in each country – 74% in Britain – said they were already seeing the influence of the climate crisis in extreme weather events, such as heatwaves and floods, and around two-thirds described it as a direct threat to ordinary people in their country.

Moreover, the last few months have brought more extreme weather events across the globe, just as anticipated by the science, and a rising level of alarm over increasing carbon emissions and global governmental failure to take effective action. And we have also seen direct action protests from the Extinction Rebellion movement. Prima facie the public is “way ahead” of politicians in recognising the scale of the climate crisis.

But in the election campaign so far climate has been the dog that does’nt bark. All the major parties are committed to the zero carbon by 2050 target or earlier, but since they will never be held to account for failure on that timescale, what matters more is the credibility of their specific policies. The smaller parties have made the best efforts, but the current Prime Minister appears reluctant to debate the subject in front of the electorate, perhaps understandably given the climate sceptic history of many in his party. Labour has a better story to tell, not least with Blair’s ground-breaking 2008 Climate Act, but has preferred to concentrate on other issues.

So why is this critical subject getting so little attention.

The real reason for reticence on climate is that it would put a spotlight on trade, and raise difficult questions about Britain’s future post Brexit.

Both major parties are anxious to avoid any discussion whatsoever of the future for British trading relationships with the rest of the world. The Conservative government is promoting a “Get Brexit done!” message in the hope that it can avoid impossible to answer questions of exactly what benefits will flow from that, and in the certain knowledge that the actual outcome will be strongly negative if not disastrous. The Labour Party is also trying to avoid the subject altogether in its campaigning, in the vain hope of satisfying fundamentally opposed sections of the electorate, and moving on to what are (for Labour) “safer” subjects.
To see why the Conservatives are anxious to avoid scrutiny, we need look no further than the complications posed by their ambitions for a US trade deal. Since 2015, US Trade Representatives are bound by Congress not to include mention of greenhouse gas emission reductions in trade agreements and there are no prospects this ban will be lifted in the near future.[3]

Under any viable global regime climate, trade policy can be an important mechanism to incentivise and facilitate participation in global agreements to limit emissions. There are at least four potential approaches[4] that can impact on climate policies:

-       leakage and competitiveness issues, in which low carbon economies lose competitiveness in particular industries and “export” carbon emissions to potentially “dirtier” competitors who emit more carbon;

-       sanctions against non-participation in and non-compliance with international agreements ;

-       placing more of the cost of abatement on the responsible parties, whether in production or consumption; and

-       maintaining a free-trade regime that allows and encourages technology transfers.

Conversely dysfunctional trade agreements can have the opposite effect. It has been claimed[5] that the NAFTA agreement locks North America into continued exploitation of the dirtiest fossil fuels.

It is immediately clear why a US President, who considers climate science a hoax and wants an “America first” trade policy, and whose political base includes huge coal interests, would not want the subject mentioned in trade talks. The US still has substantial coal exports to Europe, and will not want to see any measures, such as international agreement on carbon pricing, or even a limited bilateral accommodation, that would reduce the competitiveness of its own industry. In addition the US has a longstanding interest, most evident in pharmaceuticals, in allowing greater opportunities to exploit intellectual property rights. In the climate policy context, this limits the rate of transfer of low carbon technologies to developing countries, generally those with the highest rates of growth in energy use and CO2 emissions.

Against this background the EU, strongly influenced by the UK and France, and despite some of the weaknesses and limitations in its climate policies, has been one of a very small number of major economies taking the climate issue seriously.

So, on the one hand we have a Conservative government reluctant to admit that its break with the EU, and promised strategy of a US trade deal, will almost certainly reduce its international influence on climate, and seriously damage future prospects for successful global policies. On the other is a Labour party, alarmed by the prospect that too much focus on climate will spill over into the Brexit issues it is trying to avoid.

[1] The biggest connection is that between neo-liberal orthodoxy, with its emphasis on a small state and deregulation, and its support for unsubstantiated denial of climate science.
[2] https://www.theguardian.com/environment/2019/sep/18/climate-crisis-seen-as-most-important-issue-by-public-poll-shows . The countries were UK, US, Canada, Brazil, Poland, Germany, Italy and France.

[3] This is referenced in the recent leaked documents on US/UK trade negotiations, and appears to be a well established US position.
[4]  Trade and Climate Change: The Challenges Ahead. 2010.. Jaime de Melo (jaime.demelo@unige.ch) and Nicole Mathys

Friday, November 22, 2019


The UK’s Green Party rightly treats climate change as the defining issue of our time, but what is the financial and policy credibility of its proposals?  We must be prepared to spend what it takes, but money is not necessarily the biggest obstacle. Focus needs to be on the practicalities.

The Green Party manifesto promises an annual budget of £ 100 billion to realise the decarbonisation of the UK economy. Some people may fear that this makes policies to “save the planet” unaffordable, but the spending and borrowing to achieve that  should not necessarily be seen as the main question.

If high levels of spending on decarbonisation are effective, they can be justified.  

The issue of climate change is rapidly becoming a major priority among the public. There is an increasing recognition by climate scientists that the world will, collectively, have to attain “net zero” carbon emissions in the not too distant future. The likely overshoot, together with any failure to fully decarbonise sectors such as agriculture and aviation, or policy failures in some countries, mean that the global economy will have to find the funds for direct extraction of CO2 from the atmosphere. Even the most optimistic views of the still undeveloped sequestration technologies for direct extraction find it hard to come up with future estimates that are realistically much below $200 per tonne[1].

This means that current CO2 emissions themselves represent a particularly insidious form of borrowing. It is borrowing that requires a future repayment in kind (ie carbon sequestration to deal with past carbon emissions). If, globally, we are already on track to be at or above sustainable targets compatible with avoiding catastrophic change, then the future burden will include the cost of removing much or even all of current emissions. In the end we will, collectively, be forced to pay what it takes to deal with the problems, or to face the even more expensive consequences.

With current annual GHG emissions in the UK running at close to 500 million tonnes of CO2 equivalent (465 in 2017), our current activity is, each year, potentially imposing a future "climate debt" of perhaps $100 billion on future citizens of somewhere who will have to pay for the clean-up. The disturbing nature of this debt is of course concealed by the fact that it remains unmonetized, and also that it simply forms part of a global pool, responsibility for which cannot easily be re-allocated to individual agents or countries.

On this basis the Green Party propositions for these extremely high levels of public spending, and the associated borrowing, are not intrinsically unreasonable or outrageous. Long term borrowing, in a non-monetised form, is what we are doing now. But that in itself does not prove the need for quite such a large public spend as the best policy now.

We shall not be forgiven.  (Charcoal drawing, Nina)

But is this a realistic or even a necessary proposition for public spending?

The first qualification to make is that the estimate of what can be usefully spent is higher than most previous estimates. The Stern Review, hugely influential in promoting the low carbon agenda, suggested that perhaps between one and two percent of global GDP needed to be devoted to decarbonisation and other measures to reduce GHG. That would be consistent with an annual spend in the £20-40 billion range. Stern argued, correctly, that this represented no more than a six to twelve month delay in reaching a given level of income by 2050.

A second qualification is that this does not necessarily equate to this level of public spending. At least part of this spend will, eventually, take the form of spending by households and businesses as they adapt to the future. That may for example include personal investment in electric vehicles or in adaptation of domestic heating systems to conform to new low carbon standards.

A third qualification is that it may simply not be possible for us to spend, usefully and quickly, the amount of money suggested by the Green’s budget. Electric vehicles, heat networks, and heat pumps are all a long slog and it is unlikely that we have the labour or the skills to do all those things at the speed the Green Party programme implies.

Where Greens are right of course is that we and others need to be doing more, and faster. In particular we should be putting in place the institutions that will in due course facilitate the investments we need. Elsewhere I have proposed the idea of a National Heat Authority to promote and coordinate plans for carbon-free heat, and to initiate local proposals for (up to) city-scale heat networks which may in due course be managed and financed through local authorities. A very effective use of the money, too, if the political will can be found and successful project implementation assured, may well be to support some of the initiatives to promote climate compatible growth in the developing world.

There are plenty of feasible options available which are essential to accelerating our current downward trend in emissions, and may help postpone reliance on actual carbon sequestration. We certainly need to spend significantly more, but not necessarily, yet, in UK located investments, on the scale that the Green Party has proposed.

As a global community we should be taking action, to the practical limits, to mitigate climate change. And in its level of ambition the Green Party deserves our wholehearted support. Greta Thunberg is right. We shall not be forgiven if we fail. 

[1] One major issue for costs is that not only does the CO2 have to separated, it then has to be safely stored, either by a further process of combining with other elements to a solid state, or by the energy intensive process of pumping into deep oceans.

Saturday, November 16, 2019


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.


[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.

Monday, November 11, 2019


 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.


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.

[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..