Category Archives: carbon taxes

A wealth of ideas about wealth funds

There are many ways of designing a wealth fund based on revenues from carbon pricing.  Debate about these is necessary, but should not distract from the merits of the broader proposal. 

Last month I outlined the value of the carbon emissions, and the possibility of establishing a wealth fund based on revenue from carbon pricing.  This post provides some brief responses to questions that have been raised in response to this proposal.   There are many good design options to choose from.

Would the fund necessarily be national?

No.  There are many national wealth funds in operation, and national carbon wealth fund may well be a pragmatic way forward in many cases.  However, the Alaskan wealth fund is an example of a state based scheme, and others would be possible.  In the EU a fund could also be established either at EU or Member State level.  An international fund would be difficult and perhaps impossible to establish, but would appropriately reflect global nature of the climate change problem.

How would such a fund be governed?

There are many options here.  The most important criterion is that governance should benefit the ultimate owners of the asset, namely citizens, rather than the state or special interest groups.  This implies some independence from government.  Other criteria such as transparency and ethically sound investment will also be important[1].  Some have advocated a fully independent trust fund.  However in practice some degree of government oversight is likely to be required[2].

How would this global public good be allocated internationally?

The distribution between nations of access to the atmosphere has proved a major point of contention in global negotiations on limiting climate change, and this situation appears unlikely to change[3].  However existing carbon pricing regimes – or simply emitting free of charge – already use up a global public good.  Giving citizens and governments a greater stake in increased carbon prices is likely to decrease the quantity of emissions, and so the proportion of the global commons used[4].  This makes the approach I have proposed more compatible with good stewardship of the global commons than existing arrangements, at least for the next 50 years until revenues start to decline.

What would the macro-economic effects be?

These effects would probably not be large, at least for a national UK fund.  The payment into a UK fund would be around £16 billion p.a. at present, a little under 1% of GDP per annum[5].  This would be unlikely to cause major economic dislocation, especially if phased in over a few years.  The fund would grow large over time, reaching around £860 billion by the end of the century[6].  However this is not vastly larger than the Norwegian fund today, which is for a very much smaller economy.  Furthermore any fund would have the effect of redirecting revenue from consumption to investment, which would probably have a positive macroeconomic effect in the context of historic UK underinvestment.

Would such a measure be socially regressive?

The concern here is that poorer households spend a larger proportion of their income on energy than richer households, and so energy taxes, and thus carbon taxes, tend to hit them disproportionately harder.  However poor households still spend less on energy, and therefore carbon, in absolute terms than richer households, so an equal dividend, as I’ve proposed, would have a net progressive effect.   Furthermore, households account for only a minority of energy use, but would get the full benefit of dividends (or at least a large proportion), increasing the extent to which it is progressive.

However there are some important intergenerational issues to consider.   The proposal for a fund takes the view that present generations should safeguard capital assets so they retain value to future generations.  This is in line with the standard definition of sustainable development[7].  However there are distributional issues here which need to be addressed.  Some present citizens will be worse off.

How would it fit with other green taxes?

The proposal is clearly consistent with using green taxes more widely as a policy instrument.  What’s different from the standard approach to green taxes is the suggestion of placing revenue in capital fund rather than using revenue to fund current expenditure.  The landfill tax to which I referred in my original post currently raises around a billion pounds per annum[8].  It would be natural to add this revenue to a UK wealth fund.

Would distribution to citizens be the only use for funds?

There is no reason some of dividends from the fund should not be used to fund things like R&D.  As I have previously discussed there are many legitimate calls on revenue from carbon pricing.  However there are many compelling arguments for allocation direct to citizens, and this should in my view be a priority for the fund.

Each of these questions requires further elaboration of course, and there are many other questions to be resolved.  The design of any major new institution such as a carbon wealth fund will require a great deal of consideration of a range of issues.  However further examination appears to strengthen rather than weaken the case for such a fund.

Adam Whitmore – 22nd  March 2017

Thanks to John Rhys for raising some of these issues.  A variant of this post, responding to John’s points, was published on his website. 


[1] See Cummine (2016) cited in my original post for further details For a specific proposal for a UK wealth fund:

[2] See Barnes, Who Owns the Sky (2001)

[3] This problem does not arise for the conventional resources (such as oil and gas) that typically provide the income for sovereign wealth funds of the nations where the resources are located. There is an interesting question as to whether countries should have full property rights to natural resources within their territories, as is often assumed at present, but this is too large a subject to go into here.

[4] The assumption here is that increasing prices from current low levels will increase revenue.  Carbon prices would increase by a factor of say five or more in many cases, and it is unlikely that emissions would decrease by an equal factor – though if they did it would be very good news.

[5] This assumes 400 million tonnes of emissions are priced, compared with 2015 totals of 404 million for CO2 and 496 total greenhouse gases (source: BEIS), implying a high proportion of emissions are priced.  The carbon price is assumed to be £40/tonne, roughly the Social Cost of Carbon at current exchange rates and well above current levels.  This would give total revenue of £16 billion in the first year, less than 1% of UK GDP of approximately £1870 billion in 2015. (source: )

[6] Assuming that the UK reduces its emissions in line with the Climate Change Act target of an 80% reduction from 1990 levels by 2050, and then to zero by the end of the century, and that 80% of emissions are priced at the Social Cost of Carbon as estimated by the US EPA, converted at current exchange rates of $1.25/£.

[7] Sustainable development is usually characterised as meeting the needs of present generations without compromising the ability of future generations to meet their own needs.


How not to squander $130 trillion

Carbon pricing should be used to establish wealth funds from which current and future citizens can benefit. 

The world has a limited carbon budget …

Climate change depends on the cumulative total of emissions of greenhouse gases, so total cumulative emissions globally must be limited by the need to limit climate change.  This limited total of cumulative emissions is sometimes referred to as a global carbon budget.  Specifically, if global mean surface temperature rises are to be limited two degrees centigrade, as now mandated in the Paris Agreement, total cumulative CO2 emissions from now on must be limited to around 1600 billion tonnes of CO2[1]. From this perspective the atmosphere is a finite resource that can only be used once, rather like any exhaustible natural resource, with the important caveat that (unlike many natural resources) no more atmosphere remains to be discovered.

But currently the value of this resource is being squandered …

At the moment only a very small proportion of greenhouse gas emissions is priced adequately.  Most emissions remain unpriced, and the growing proportion that is priced is mostly sold at well below both the cost of damages, and well below the value of an increasingly scarce resource.  A valuable scarce resource is thus being given away or sold below cost, subsidising emitters.  Huge natural wealth is being squandered.  And once gone it can never be replaced[2].

It would be better to use revenue from carbon pricing to create a wealth fund to benefit both current and future generations …

So is there a better approach to managing this precious resource?  It seems to me that there is. It would be much better to realise value of emissions in the form of a fund for citizens, with proceeds from carbon pricing (the sale of allowances or taxes) at adequate levels paid into the fund.  Carbon pricing should be comprehensive, with prices at adequate levels.  The finite volume of the resource implies it is best used to establish a wealth fund, where financial capital is built as natural capital is used up.  The fund would belong to all citizens.  Granting its value to citizens would surely encourage better management of the atmosphere, and thus the climate, and higher carbon prices than generally prevail at present.

Such a fund would be analogous to a sovereign wealth fund based on oil and gas reserves, of which the Norwegian fund is the leading example[3].  Wealth is invested in productive activity, with the income from this available to fund pensions and other expenditure. So, how much might this resource be worth in purely financial terms?

Such a fund could be enormously valuable …

Each tonne of CO2 emitted to the atmosphere should be priced at a minimum of the cost of damages from climate change – the social cost of carbon. This is currently around US$50/tonne, and rising over time.  Emissions may be more valuable than this, either because of the limitations in estimates of the social cost of carbon (see here), or because the value of the emissions in terms of the economic activity they enable is greater than their cost in environmental damage.  But evaluating the resource at its cost at least puts a lower bound on its value, unless the economic value of those emissions is below the cost assumed here, which seems unlikely with such a constraining budget[4].

The profile of emissions also matters.  For simplicity I’ll assume current emission levels to 2020, then a linear decrease to the end of this century[5].  This is broadly similar to many emissions tracks that have been modelled as consistent with 2 degree warming, and (consistent with this) the cumulative total is close to the 1600 billion tonnes budget I mentioned above.  It is also consistent with the Paris Agreement goals of reaching net zero emissions at some point in the second half of the century[6].

The annual value of emissions is then estimated from multiplying the (rising) cost of emissions with the (falling) quantity of emissions.  This is shown in the chart below.  The effects of rising prices and falling emissions roughly balance over the next 50-60 years or so, with revenues remaining roughly similar at close to $2 trillion p.a..  Revenues then fall rapidly in the last quarter of the century as emissions fall to zero.  The eventual value of the fund, excluding investment returns and dividends paid out, is the sum of these annual revenues (the area under the curve).

Chart: Potential annual revenue into carbon funds globally … chart

On this basis, the total value of the remaining carbon budget is a staggering $130 trillion.  This is equivalent to $13,000 for each person in the world, assuming world population of 10 billion people later this century.  A 3% annual dividend from this would generate about $400 p.a. for everyone .

Towards a citizens’ dividend …

Dividends from the fund could be used in many ways.  One approach with a range of advantages is distributing benefits to all in the form of a “citizen’s dividend”.  There is already a feature of the Alaskan wealth fund derived from oil revenues, where distribution is in the form of a Permanent Fund Dividend to all citizens.  This is widely considered to have helped build and maintain public support for the scheme[7].

This approach is closely related to the idea of “tax and dividend” carbon pricing.  I have previously argued that such approaches have merit, and indeed tax and dividend has recently been advocated by senior Republicans in the USA[8].  However, there is an important difference between a fund and tax and dividend as often presented, in that revenues are used to establish a fund that is intended to be permanent, whereas tax and dividend proposals often assume revenues to be distributed in full.

There is also a relationship between the idea of a citizen’s dividend and a universal basic income, which is much discussed at the moment and subject to a few trials.  However, there is a crucial difference in that the citizen’s dividend does not seek to provide an adequate income.  Rather it is simply a return on funds invested.  Instead, it is likely to be one component of any universal basic income.

Who would benefit?

There is a natural case for distributing dividends equally, as all have equal rights to the atmosphere.  The atmosphere is a global resource, and climate change knows no borders, so it is natural to make any fund global.  However establishing such an arrangement is likely to be too great a political challenge.

A bottom up approach with individual nations pricing carbon and establishing their own funds is likely to be much more tractable.  Such a national approach would have other advantages.  For example, it would allow other environmental taxes, such as those on landfill, and indeed other sources of revenue to contribute to the fund.  A series of national funds would not stop any fund being used to finance activities of international benefit – indeed such uses would be highly desirable.

Establishing national funds will have many challenges.  However the prize seems large enough to be worth pursuing.  The current system of simply allowing emissions to be dumped into the atmosphere, often free of charge and almost always too cheaply, is a waste of a unique and irreplaceable asset.  Irreplaceable natural wealth such as the atmosphere should be managed carefully, not squandered recklessly.

Adam Whitmore – 13th February 2017 

[1] Based on “Warming caused by cumulative carbon emissions towards the trillionth tonne”.  Allen et. al. Nature vol. 458 (2009), adjusted for emissions since the publication of that paper.

[2] Many people, including me, would also wish to note the ethical dimension here.  It is not appropriate to treat the atmosphere only as mere resource for people to use as they wish, and all decisions about its management must reflect ethical considerations, including responsibilities to future generations, and the duty of care to the world’s natural heritage.  I am simply arguing here that treating it as valuable resource would be a major step forward from treating it as a resource to be used as though it were unlimited and emissions were inconsequential, as is often the case at present.

[3] For an excellent review of Sovereign Wealth Funds and how they could be better managed and used for the benefit of citizens see Angela Cummine, Citizens’ Wealth, Yale University Press, 2016.

[4] If the price would be lower than the SCC with this emissions track it implies that the 2 degree target is too loose and 1.5 degree or lower would be preferred.

[5] This is a rough and ready calculation, taking CO2 emissions from energy and industry only.  It ignores the effect of other gases and effectively assumes other sources of CO2, mainly deforestation, are approximately net zero cumulatively over the century after taking into account the role of sinks and deforestation.  This may be optimistic.  Adjusting for these would lead to a higher starting point and steeper decrease in emissions, reducing somewhat the value of the fund.

[6] In this scenario emissions are low enough to be balanced by a small quantity of negative emissions by the last decade of the century.

[7] See Angela Cummine, Citizens’ Wealth, Yale University Press, 2016., p.140-2.

[8] See “US Republican elders push for carbon tax”, Carbon Pulse, 8th February 2017

Can emissions trading produce adequate carbon prices?

Prices under emissions trading schemes have been low to date.  Sometimes this may be because systems are new, but the EUETS is long established and needs to demonstrate that it can now produce adequate prices. 

Prices under emissions trading systems around the world have so far remained low.  The chart below shows carbon pricing systems arranged in order in increasing price, with prices on the vertical axis shown against the cumulative volume covered on the horizontal axis.  Carbon taxes are shown in purple, emissions trading systems in green.  It is striking that all of the higher prices are from carbon taxes, rather than emissions trading systems.

Prices under Emissions Trading Systems and Carbon taxes in 2016


Source:  World Banks State and Trends of carbon pricing report[1].  Prices are from mid-2016.

Prices in the largest emissions trading system, the EUETS have been around $5-6/tonne, and prices in the Chinese pilot schemes have been similar and in some cases even lower, although with little trading.  The price under the California and Quebec scheme (soon to be joined by Ontario) is somewhat higher.  However, this is supported by a floor set in advance and implemented by an auction reserve price.  If this price floor were not present a surplus of allowances would very likely have led to lower prices.  The Korea scheme has had very low trading volumes, so does not provide the same sort of market signal found under more liquid schemes.

In contrast, a wide range of carbon taxes are already at higher levels and in some cases are due to increase further.  The French carbon tax, which covers sectors of the economy falling outside the EUETS, is planned to reach €56/tCO2 (US$62/tCO2) in 2020 and €100/tCO2 (US$111/tCO2) in 2030[2].  In Canada a national lower limit on carbon prices for provinces with an explicit price-based system (not shown on the chart) is due to reach $50 per tonne in 2022[3]. The UK carbon price floor, which covers power sector emissions, was due to rise to substantially above current levels, but is currently being kept constant by the Government, mainly because the price under the EUETS is so low.

Increases such as those due in France and Canada will bring some carbon taxes more in line with the cost of damages, and thus to economically efficient prices.  The cost of damages is conservatively estimated at around $50/tonne[4], rising over time (see here for a discussion of the social cost of carbon and associated issues).  The increases will also bring prices more into line with the range widely considered to be necessary to stimulate adequate low carbon investment[5].

Low prices under emissions trading systems have been attributed to a range of factors, including slower than expected economic growth and falling costs of renewables[6].  However these factors do not explain the consistent pattern of low prices across a variety of systems over different times[7].

While it is difficult to derive firm evidence on why this pattern should be present, two factors seem plausible.  The first is systematic bias in estimates – industry and governments will expect more growth that actually occurs, costs will be overestimated, and these tendencies will be reflected in early price modelling, which can often overstate likely prices.

But the second, more powerful, tendency appears, based on anecdotal evidence, to be that there is an asymmetry of political risk.  The political costs of unexpectedly low prices are usually perceived as much less than those of unexpectedly high prices, and so there will always be tendency toward caution, which prevents tight caps, and so leads to prices being too low.

This tendency is difficult to counteract, and has several implications for future policy.

First, it further emphasises the value of price floors within emissions trading systems.  Traditional environmental economics emphasises the importance of uncertainty around an expected level of abatement costs or damages.  If decision makers are not in fact targeting expected average levels, but choosing projections of allowance demand above central expectations then the probability of very low prices is increased, and the case for the benefits of a price floor is stronger.

Second, it implies that it is even less appropriate than would anyway be the case to expect the carbon price alone to drive the transition to a low carbon economy.  Measures so support low carbon investment, which would in any case be desirable, are all the more important if the carbon price is weak (see here for a fuller discussion of the value of a range of policy measures).   While additional measures do risk further weakening the carbon price, they should also enable reduced emissions and tighter caps in future.

Third, it requires governments to learn over time.  Some low prices may reflect the early stage of development of systems, starting slowly with the intention of generating higher prices over time.  However this does require higher prices to eventually be realised.

The EUETS has by some distance the longest-established system, having begun eleven years ago and with legislation now underway for the cap to 2030, by which time the system will be 25 years old.  The EU should be showing how schemes can be tightened over time to generate higher prices.  However it now looks as though the Phase 4 cap will be undemanding compared with expectations (see previous posts).  The recent vote by the European Parliament’s ENVI committee failed to adopt measure that are adequate to redressing the supply demand balance, with tweaks to the market stability reserve unlikely to be enough.  This undermines the credibility of cap-and-trade systems more generally, rather than setting the example that it should.  Further reform is needed, including further adjustments to supply and preferably auction reserve prices.

The advantages of cap-and trade systems remain.  Quantity limits are in line with the international architecture set by the Paris Agreement.  They also provide a clear strategic signal that emissions need to be reduced over time.

However there is little evidence to date that emissions trading systems can produce adequate prices. The EU, with by far the most experience of running an ETS, should be taking the lead in substantially strengthening its system.  At the moment this leadership is lacking.  Wider efforts to tackle climate change are suffering as a result.

Adam Whitmore – 23rd January 2017


[2] World Bank State and Trends in Carbon Pricing 2016.  See link in reference 1.

[3]  Canadian provinces with volume based schemes such as Quebec with its ETS must achieve emissions reductions equivalent to these prices.

[4] $40/tonne in $2007, see, escalated to about $50 today’s dollars.

[5] See this recent discussion:

[6] Ref: Tvinnereim (2014)


[7] The South Korea ETS may be a partial exception to the pattern.  However it is unclear due to the lack of liquidity in the market.

Additional actions in EUETS sectors can reduce cumulative emissions

It is often claimed that additional actions to reduce greenhouse gas emissions in sectors covered by the EUETS are ineffective because total emissions are set by the level of the cap.  However this claim is not valid in the current circumstances of the EUETS, and is unlikely to be so even in future.  Additional emissions reduction measures in covered sectors can be effective in further permanently reducing emissions.

This post is longer than usual as it deals with a very important but relatively technical policy issue.

The argument about the effectiveness of additional actions to reduce emissions …

Many additional actions are being taken to reduce greenhouse gas emissions in sectors covered by the EUETS.  These include energy efficiency programmes, deployment of renewables, replacing coal plants with less carbon intensive generation, and national carbon pricing.

It is often argued that such additional actions do not reduce total emissions because the maximum quantity of emissions is set by the EUETS cap, so emissions may remain at the fixed level of the cap, irrespective of what other action is taken (see the end of this post for instances of this argument being used publicly).

However, this argument does not stand up to examination.

Assessment of the argument needs to take account of the current circumstances of the EUETS.  Emissions covered by the EUETS were some 200 million tonnes (about 10%) below the cap in 2015.  This year emissions are likely to be 13% below the cap.  The EUETS currently has a cumulative surplus of almost three billion allowances, including backloaded allowances currently destined for the Market Stability Reserve (MSR), and the surplus is set to grow as emissions continue to be less than the cap.

In these circumstances emissions reductions from additional actions will mainly increase the surplus of allowances, with almost all of these allowances ending up in the (MSR).  These allowances will stay there for decades under current rules, and so not be available to enable emissions during this time.

Indeed, in practice these allowances are unlikely ever to enable additional emissions.  The argument that they will assumes that the supply of allowances is fixed into the long term.  In practice this is not the case.  Long term supply of allowances is determined by policy, which can and does respond to circumstances.  Additional surpluses and lower prices are likely to lead to tighter caps than would otherwise be the case, or cancellation of allowances from the MSR or elsewhere.

The remainder of this post looks at these issues in more detail, including why the erroneous view that additional actions don’t reduce cumulative emissions has arisen.

Why current circumstances make such a difference

The argument that additional actions to reduce emissions will be ineffective reflects how the EUETS was expected to operate when it was introduced. It was assumed that demand for allowances would adjust so that the quantity of allowances used would always equal to the cap, which was assumed to be fixed.

This is illustrated in stylised form in the diagram below.  The supply curve is vertical – perfectly inelastic supply.  Demand for allowances without additional actions leads to prices at an initial level.  Additional actions reduce demand for allowances at any given price, effectively shifting the demand curve to the left by the amount by which additional actions reduce emissions.  This leads price to fall until the lower price creates sufficient additional demand for allowances, so that total demand for allowances is again equal to the supply set by the cap.  Because the supply curve is fixed (vertical) the equilibrium quantity of emissions is unchanged, remaining equal to the cap[1].

Chart 1: A price response to the change in demand for allowances can lead to emissions re-equilibrating at the cap when allowances are scarce …


However, at present, large increases in emissions (such that emissions rise to the cap) due to falling prices are clearly not occurring, and they seem unlikely to do so over the next few years.  As noted above, the market remains in surplus both cumulatively and on an annual basis.  The price would be close to zero in the absence of banking of allowances into subsequent phases, because there would be a cumulative surplus over Phase 3 of the EUETS, and so no scarcity[2].

If demand were further reduced in the absence of banking there would be no price fall, because prices would already be already close to zero.  Correspondingly, there would be no increase in demand for allowances to offset the reduced emissions from additional actions.  The emissions reductions from additional actions would be retained in full. This is again illustrated in stylised form in the diagram below. 

Chart 2: With a surplus of allowances and price close to zero (assuming no banking) any reduction in demand for allowances will be retained in full …


In practice the potential to bank allowances and the future operation of the MSR supports the present price.  It is expected that in future as the cap continues to fall allowances will become scarce.  There is thus a value to allowances set by the cost of future abatement.

Additional actions now to reduce emissions increase the surplus, and so postpone the expected date at which the market returns to balance.  This reduces current prices.  This will in turn lead to some increase in emissions.  However, this increase will be small – much smaller than if the market were short of allowances now.

Quantifying this effect 

Modelling indicates that if additional actions are taken over the next 10-15 years, then the increase in demand for allowances due to falling price will be less than 10% of the size of the reduction in emissions[3].  Correspondingly more than 90% of the emissions reductions due to additional actions are retained, adding to the surplus of allowances which, which end up in the MSR.  Modelling parameters would need to be in error by about an order of magnitude to substantially affect this conclusion.

This effect arises in part because of the low level of prices at present.  This means that even a large percentage change in price leads to a small absolute change, and thus a small effect on demand for allowances.  Even a 50% price fall would be less than €3/t at current price levels.  It also reflects that the shape of the Marginal Abatement Cost curve, with price falls only increasing abatement by a small amount.  This means that even if prices are higher than current levels the effect of price falls on demand for allowances is still relatively small.

The relatively small response to price changes is consistent with the current market, where there is a lack of sufficient increase in demand to absorb the current yearly surplus (or even to come close to doing so).

The 90%-plus of the allowances freed up by additional actions are added to the surplus end up over time in the MSR.  They then stay there for several decades.  This is because even without additional actions, and even with some reform of the current proposals for Phase 4 (which covers 2021 to 2030), the MSR is likely contain at least three billion allowances by 2030, and perhaps as much as five billion.  This will take until 2060 to return to the market, and perhaps until the 2080s, at the maximum rate written into the legislation of 100 million per annum.

Any additional surplus will only return after this.  Even if the return rate of the MSR were doubled the return time for additional surplus would still be reckoned in decades from now.

This will be even more the case if proposals for the EUETS Phase 4 are not reformed, and the surplus of allowances being generated anyway is correspondingly greater.

The implications of the very long delay in the return of allowances

It seems unlikely that allowances kept out of the market for so long would ever lead to additional emissions.  It would require policy makers to allow the allowances to return and enable additional emissions.  This would be at a time when emission limits would be much tighter than they are now, and indeed with a commitment under the Paris Agreement to work towards net zero emissions in the second half of this century.

There are several policy mechanisms that could prevent the additional surplus allowances enabling emissions.  Subsequent caps tighter as unused allowances reduce the perceived risk of tighter caps, and additional actions now set the economy on a lower carbon pathway.  Furthermore, with a very large number of allowances in the MSR over several phases of the scheme, allowances may well be cancelled.  Indeed, over such long periods the ETS itself may even be abolished or fundamentally reformed, with allowances not carried over in full.  Or a surplus under the EUETS may persist indefinitely as additional actions succeed in reducing emissions.

As the market tightens towards 2030 it is likely that a higher proportion of any additional emissions reductions will be absorbed by the market via a price effect, but it still seems unlikely to be as much as 100% given the long term trend to lower emissions and the lack of additional sources of demand, especially in the event of large scale additional actions[4].  Some of the policy responses described would still be expected to reduce the supply of allowances.


The argument that emissions will always rise to the level of the cap manifestly does not hold at present, when emissions are well below the cap. and there is a huge cumulative surplus of allowances.

In future, it seems likely that more than 90% of reductions in emissions from additional actions will simply add to the surplus, and eventually end up in the MSR.  They at least stay there for several decades, because of the very large volume that will anyway be in the MSR.

While there is in principle a possibility that they will eventually return to the market and allow additional emissions this appears most unlikely in practice.  Policy decisions will be affected by circumstances and this can readily prevent additional emissions, through some combination of tightening of the cap and cancellation of allowances.

Even when the market returns to scarcity these policy responses are likely to hold to a large extent, for example with lower prices enabling more stringent caps.  The hypothesis of no net reductions in emissions from additional actions thus seems unlikely ever to hold true.

Spurious arguments about a lack of net emissions reductions should not be used as a pretext for failing to take additional actions to reduce emissions now.

Adam Whitmore – 21st October 2016


Note:  A more detailed review of the issues raised in this post, and the accompanying modelling can be found in this report.


Examples of statements invoking the idea of fixed total emissions

For example, in 2015 RWE used such arguments in objecting to the closure of coal plant:

“The proposals [to reduce lignite generation] would not lead to a CO2 reduction in absolute terms.   [The number of] certificates in the ETS would remain unchanged and as a result emissions would simply be shifted abroad.” [5]

Similarly, in 2012 the then Chairman of the UK’s Parliament’s Energy and Climate Change Select Committee, opposed the UK’s carbon price support mechanism for the power sector arguing that:

“Unless the price of carbon is increased at an EU-wide level, taking action on our own will have no overall effect on emissions”[6]

Neutral, well-informed observers of energy markets have also made this case.  For example, Professor Steven Sorrel of Sussex University recently argued that:

“Any additional abatement in the UK simply ‘frees up’ EU allowances that can be either sold or banked, and hence used for compliance elsewhere within the EU ETS[7]



[1] This is analogous to the well-established rebound effect for energy efficiency measures.  Improved domestic insulation lowers the effective price of energy, so consumers take some of the benefits as increased warmth, and some as reduced consumption.  The argument here is that in effect there is a 100% rebound effect for emissions reductions under the EUETS.

[2] Such a situation occurred towards the end of Phase 1 of the EUETS (2005-7), which did not allow banking into Phase 2.  Towards the end of the Phase there was a surplus of allowances and the price fell to close to zero.

[3] The price change is modelled by assuming the price is set by discounting future abatement costs, with a later date for the market returning to balance leading to greater discounting and so a lower price.  The increase in demand for allowances is modelled based on a marginal abatement cost curve and consideration of sources of additional demand.  See report referenced at the end of this post for further details of the modelling.

[4] There are likely to be path dependency and hysteresis effects in the market which prevent a full rebound.

[5] See RWE statement, “Proposals of Federal Ministry for Economic Affairs and Energy endanger the future survival of lignite”, 20 March 2015.



The EUETS and the need for price floors (and maybe soft ceilings)

Standard objections to introducing price containment mechanisms into the EUETS carry little weight.  It’s time to give price containment more serious consideration.

With the price of allowances in the EUETS currently down at around €4/tCO2 the question of whether direct price containment (price floors and ceilings) should be introduced has naturally been the subject of renewed debate, especially in the light of the French proposal earlier this year to introduce a price corridor.

The debate tends always to feature a standard set of objections to price containment.  Most of these lack validity when applied to well-designed mechanisms.  Here I take a look at why this is so, in the hope that the debate can become more realistic and constructive, focusing on the benefits and design challenges around price containment.

The broad themes underpinning the rationale for price containment are as follows:

  1. All emissions of GHGs are damaging, not just those above the cap. Reducing emissions below the cap and further tightening the cap thus have benefits.
  2. The financial cost of damages emissions (the social cost of carbon – SCC), although uncertain, is well above current prices[1]. This implies that further emissions reductions with a cost between the current price and the cost of damages have a net benefit.  However these are not currently being incentivised by the carbon price.  This is one reason why a floor prices is beneficial.
  3. The market structure and parameters are set by regulatory decisions. These decisions are inevitably taken under uncertainty, and market design is about optimising outcomes under uncertainty.  Design is more robust to uncertainty with both price and quantity targets than with either alone.
  4. Supply adjusting in response to price makes the EUETS more like a normal market.
  5. It is essential for reasons of international obligations and environmental integrity that the cap is maintained[2], so moving to a pure carbon tax is not a good idea.

Based on these premises the following responses to standard objections to price management can be made.

“Price management is interfering in the market”

The form of the market is a politically determined construct. Modifications to this construct are appropriate to correct shortcomings in the current design, where supply is too rigid to accommodate uncertainties. The cap does succeed in limiting the total emissions but fails to produce adequate signals for additional abatement.   Modification is required to reduce supply of allowances if prices become too low, in order to retain efficient price signals.

Allowing the supply of allowances to respond to price is not interfering with the day-to-day operation of the market. On the contrary, it is designing it to function more like a normal market.  In most markets supply varies with price (elasticity of supply is not zero in most markets[3]).

 “There is no environmental benefit to a floor price because the cap does not change” or “it does nothing to reduce supply or increase ambition towards targets in the Paris Agreement”

The critical question here is what happens to unsold allowances. There are many possibilities for dealing with unsold allowances, including cancelling them at the end of a phase, cancelling a proportion at the end of a phase, or cancelling them on a rolling basis.

Provided that there are appropriate provisions for cancelling unsold allowances, total emissions over time can be reduced, and so there is a clear environmental benefit.  Even if this is not the case, allowances may simply stay in the reserve, or caps may be tighter in future due to emissions reductions achieved, also creating an environmental benefit.

“If the EU is meeting its target at low cost the price should be correspondingly low”

No it should not.  The low price signals that the target is not stringent enough to adequately reflect damages.  All emissions are damaging, even those within the cap, and if more abatement can be achieved at lower cost than the damage caused this is what should happen.

Measures which further decrease emissions in response to lower cost of abatement also help reinforce the EU’s international leadership position on climate change.

“It goes against the quantity based nature of the EUETS” or “it’s introducing a carbon tax”

Prices can managed by automatically adjusting supply in response to price, for example by putting a reserve price in auctions.  This is entirely consistent with the quantity based nature of the EUETS, in that it works by adjusting quantity.  Indeed, as noted, it makes the EUETS more like almost all other markets where the quantity of supply varies in response to market prices.

It is possible to use tax-based measures to impose a floor, as the UK does and France will do from January 2017, but it is not necessary to do so.

Characterising price floors  as a tax appears often to be used as a way of creating political momentum against the idea.  An EU tax requires unanimity among Members States and attempts to introduce a carbon and energy tax in the 1990s were notably unsuccessful, and similar efforts would doubtless prove challenging.  Characterising floors as a tax may also help develop political opposition to a floor.  Branding the Australian ETS as a tax (which it was not) was successful in helping build opposition there, with eventual repeal of the scheme.  Price management through adjusting quantities should not be misrepresented in this way to artificially discredit it.

“It reduces market efficiency”

This confuses efficiency of trading with efficiency of the price signal.  If you were never to change the number of allowances, trading alone might indeed remain the most efficient way of meeting the cap.  However this has created prices which failed to adequately signal efficient abatement (in effect the market is telling you that the current cap is too loose).  There is thus a misallocation of resources towards to many emissions and too little abatement.

“The price may be set at the wrong level”

Having both price and quantity limits increases robustness to the unexpected.  If the cap has been set at appropriate levels then prices will anyway lie within the range of any  price containment, and price limits will not bind.  However the existing EUETS cap has been set at a sub-optimal level –too many allowances have been issued and the price is too low.

Limiting the price simply recognises that future demand for allowances may be mis-estimated, or the level of the cap may be subject to biases, for example due to asymmetries of political risk from setting the cap too high or too low.

 “It will never be possible to agree a price”

Price will doubtless be contentious but there are several reference points, notably the following:

  • estimates of the SCC, which represents the financial cost of damages, although calcualtions typically exclude important costs of damage. The SCC is highly uncertain, but well above the €4/tonne currently prevailing in the EUETS under almost any reasonable set of assumptions.
  • prices under other schemes, especially those with price management;
  • prices consistent with those needed to signal abatement sufficient to reach climate targets.

This gives a framework of negotiation.  The level of the cap, which is always set with a view to abatement costs and prices, is anyway contentious.

There are many difficult issues to resolve in designing appropriate price containment mechanisms for the EUETS and setting price boundaries at appropriate levels.  Spurious objections such as the ones discussed here should not be allowed to form an obstacle to much-needed debate about the best way forward.

Adam Whitmore – 14th September 2016

Note:  The advantages of hybrid price quantity instruments have been extensively reviewed in the environmental economics literature, going back to the original paper on the subject by Roberts and Spence Effluent Charges and Licenses Under Uncertainty (1976).  Understanding the need for prices to fully reflect the cost of environmental damages goes back further, to Pigou “The economics of welfare” (1920).  See standard texts on environmental economics for a fuller treatment.  These conclusions are not uncontentious, in particular because some observers continuing to favour a carbon tax.  My own view remains that including a cap on emissions is preferable, and that many of the advantages of a carbon tax can be realised by a well-designed floor price.

[1] Furthermore there are other non-priced damages which imply the benefit of abatement is greater than implied by the SCC.

[2] Also, any ceiling should be soft to allow prices to rise above the ceiling rather than allowing emission to go above the cap, for example with allowances in price containment reserve taken from within the cap.

[3] Almost the only markets with completely fixed supply are the markets for tickets to major sporting events and for authentic works by dead artists.  For example the number of tickets to the men’s final at the Wimbledon tennis championships is limited by the number of seats, and the number of authentic Picasso’s cannot now increase with price (although the number of fakes can).


Uses of revenues from carbon pricing

There are many worthwhile uses for revenues for carbon pricing.  In practice a mixture of uses is likely to be found. 

My previous post estimated that carbon pricing will raise around $22 billion worldwide this year, and suggested that this has the potential to grow by an order of magnitude.  This post looks at how revenues might be used.

Revenues from carbon pricing can be used for both climate change related purposes and more general purposes.  The main categories are summarised in the table, and described briefly below.

Summary of potential uses of revenue raised by carbon pricing

General fiscal and social goals Climate change related purposes
Support for vulnerable groups Adaptation
Reduction of other taxes Distribution to those affected by climate change
Government retention of revenues Support for further emissions reduction, including for innovation
Returned to citizens

Support for vulnerable groups

The introduction of carbon pricing is often accompanied by concerns about the effects on energy prices on lower income households.  Rises in electricity prices to households due to pricing of power sector emissions are of concern even under schemes such as the EUETS which do not directly cover households.

Some proportion of revenue can be set aside to compensate vulnerable households.  This was a feature of the now repealed Australian scheme.

Reduction of other taxes

Other taxes can be reduced by an amount equal to the revenue raised from carbon pricing.  If this is done in full the carbon pricing scheme is usually referred to as revenue neutral.  This is a feature of the British Columbia carbon tax.

Government retention of revenues.

Governments can retain some or all of the revenue for general expenditure or deficit reduction.  This is, for example, the case in the UK, where the Treasury has a long history of viewing taxation and expenditure as a whole, and there is resistance to earmarking (“hypothecation”) of funds.

Returned to citizens.

An equal payment can be made to all citizens in a jurisdiction (see previous post).  The Swiss carbon tax currently returns a portion of revenue equally to all citizens.  Such an approach has been proposed as part of bills at federal and state level in the USA.


Measures to adapt to climate change can be funded either within the jurisdiction that raised the revenue or internationally.  For example, in its July proposals for the next phase of the EUETS, the European Commission included provisions for Member States to use some of the revenues from the EUETS to finance actions to help other countries adapt to the impacts of climate change.

Funds could be channelled through international institutions to provide funds to match national expenditure, potentially making a substantial contribution to meeting any funding shortfalls.

Distribution to those affected by climate change

Funds could be provided to those adversely affected by climate change.  There is a continuing debate on this issue and how it relates the “loss and damage” agenda within the UNFCCC process, including the large overlap with the issue of adaptation.  However there has been little practical progress on this to date.

Support for further emissions reduction and for innovation

Funds may be provided for measures such as retrofitting homes and businesses for greater energy efficiency, and the installation of renewable energy technologies.  Revenues may also be used to fund research, development and deployment of new low carbon technologies.  A number of schemes in North America include provisions of this type, including California, RGGI and Alberta.  The EUETS has also included support for new technology from the sale of 300 million allowances from the new entrant reserve (the “NER 300”).  However funds raised from this were less than originally expected due to lower allowance prices, and the allocation process has been delayed.  The EU is now planning an Innovation Fund in the 2020s, again to be funded by the sale of allowances.

So which should be preferred?

Many uses of funds have merit, and the choice will depend on local political and economic circumstances.  However some seem to have particular arguments in their favour, with a mixture of often likely to be preferred.

Supporting adaptation and potentially also providing recompense to those adversely affected by climate change has a strong appeal on grounds of justice, and may form a valuable element of some programmes.

Returning funds equally to citizens has advantages covered in my previous post.  This could be accompanied by providing additional support to some vulnerable groups.

Finally, using revenue to fund additional emissions reductions, especially with a component of assistance for the disadvantaged, has proved understandably attractive in a number of jurisdictions in North America and to some extent in the EU.  Deeper emissions cuts will require new technologies and large-scale investment.  This in turn requires progress to be made now, increasing in scope and extent over time.  Increased use of funds from carbon pricing to support such efforts seems likely to prove worthwhile.

Adam Whitmore – 10th November 2015

Material in this post, as well as my previous one, can also be found in the Carbon Markets Investment Association (CMIA) paper at

Revenue from carbon pricing

Carbon pricing already raises over $20 billion p.a. worldwide.  This has the potential to grow by an order of magnitude.  What to do with this money will be an increasing important issue.

As carbon pricing spreads around the world (see here) substantial amounts of money are now being raised.  The amounts depend on:

  1. The coverage of each scheme
  2. The number of allowances allocated free of charge (under an emissions trading scheme) or the extent of tax exemptions and rebates (under a carbon tax).
  3. The level of the price in each scheme

Estimating these parameters for each scheme around the world indicates that about $22 billion will be raised globally this year, excluding the value of free allowances, tax exemptions and rebates.  The breakdown of this total is shown in the chart below.  (The data is a rough estimate in some cases because summary data on coverage and rebates is not readily available for some schemes, especially carbon taxes in Europe.  Also, average prices for allowances over the whole of this year are not yet known.)

About three quarters of the revenue raised is in Europe.  Interestingly, revenues from auctioning of allowances under the EUETS are lower than those from other carbon pricing in Europe, which includes carbon price support in the UK and carbon taxes in France and Scandinavia.  This is in part because EUETS revenues have been reduced this year by the postponement of some allowance auctioning (backloading).

The remainder of revenues raised worldwide are from the various North American schemes and the (rather low) carbon tax in Japan.  There is no auctioning of allowances under the New Zealand or South Korean schemes, or in China, so they don’t yet contribute to the total.

Indicative estimates of revenue from carbon pricing in 2015

revenue chart

Notes: Estimates based on prevailing prices multiplied by volumes covered, excluding freely allocated allowances and tax exemptions and rebates.  Data is estimated from a variety of sources and totals may be lower or higher or than shown as assumptions have been adopted for coverage and rebates where data is not readily available.  Small variations in coverage can affect estimates significantly in individual jurisdictions because of high prices.The Mexican carbon tax is excluded as it does not price emissions from natural gas so more resembles an energy tax on some fuels.  Other Europe includes Portugal, Switzerland and Iceland.

Revenue is significantly higher this year than it was last year, when the total raised worldwide was around $15 billion.  This mainly reflects increases in:

  • prices and volumes of EUAs auctioned;
  • the level of UK carbon price support;
  • the price and coverage of the French carbon tax; and
  • the coverage of the California and Quebec schemes, which expanded to cover transport and other sectors in January this year.

The total revenue raised has the potential to increase vastly if:

  • new schemes are introduced, especially nationally in China as planned and in the USA, or coverage of existing schemes is expanded;
  • the amount of auctioning is increased, with the amount of auctioning in the planned national scheme in China especially important; and
  • prices rise under the major schemes, including the EUETS.

Indeed, over time revenue raised globally could increase by an order of magnitude or from current levels to reach into the hundreds of billions in the longer term.  However even if revenue grows to approximately ten times current levels over the next decade or more it would still represent only perhaps 0.2% of global GDP, and so remain only a small proportion of total flows within the world economy.

This is nevertheless a substantial amount of money, and there is likely to be increasing debate about how it might best be used.  I will return to this in my next post.

Adam Whitmore – 26th October 2015

A paper on revenues from carbon pricing including much of this material has been published by the Climate Markets and Investment Association (CMIA), see