Many economists argue that the most effective policy for dealing with climate change is carbon pricing. This reduces greenhouse gas (GHG) emissions in a way that minimises the costs to the economy.
For the policy to work effectively it is important that the price per tonne of CO2 equivalent (CO2e) does not vary with the activity that causes the emissions. In other words, whether you drive a car, heat your house using gas or travel by air, the GHGs you create need to be priced at a unified rate.
Governments can introduce carbon pricing in two different ways – cap-and-trade schemes and carbon taxes.
With a cap-and-trade policy, emission allowances are either issued or sold to the organisations covered by the scheme. They must accumulate enough of these allowances to match the actual level of emissions they produce or pay a large fine. After the initial allocation, allowances can be bought and sold in a secondary market and prices can be quite volatile.
With a carbon tax, the government directly sets the price of GHGs through the tax rate but has less control over the quantity of emissions.
Policy in the UK
The UK Emissions Trading Scheme – an example of a cap-and-trade scheme – clearly places a price on GHG emissions. As this price is determined by market forces it can vary on a daily basis. The scheme applies to electricity generation and other energy-intensive industries that account for approximately 30 per cent of all emissions.
Although the UK does not have a specific carbon tax, it does have a number of different taxes that have an impact on the environment. Some of these have stated environmental objectives (e.g. the Climate Change Levy) while the main rationale for others is to raise revenue (fuel duty).
The tax rates are typically set on the output or consumption of the good rather than on emissions. For example, the Climate Change Levy applies to businesses’ use of electricity, gas and coal rather than the emissions the energy generates. Fuel duty depends on the amount of petrol consumed rather than the emissions the burning of that fuel generates. Clearly, emissions will tend to rise in proportion to the consumption/production of the good, but the relationship will not be precise.
The structure of VAT also influences emissions. The standard rate of VAT in the UK is 20 per cent. However, a lower level is applied to some goods/services that produce significant emissions. For example, the rate on household consumption of gas is 5 per cent while commercial passenger flights are zero rated. These lower tax rates are an implicit subsidy for the people who consume these goods/services. It makes them cheaper relative to the price of other goods.
Impact of the policies
Researchers from the Institute for Fiscal Studies have recently tried to analyse the impact of this complex range of policies on the price of carbon. The results indicate wide variations depending on the activity that causes the emissions.
One of the most significant differences is between gas and electricity. For example, non-energy-intensive businesses pay a price of £229.10 per tonne of CO2e from electricity generation but only £30.50 per tonne from burning gas. The response to the incentives this creates is unsurprising. One of the biggest contributing factors to the fall in territorial emissions in the UK has come from the decarbonisation of electricity supply: i.e. the switch away from coal-fired generation.
The impact of government policy on UK households creates quite perverse incentives. Because of the lower rates of VAT, families receive an implicit subsidy of £24 per tonne CO2e when they use gas to heat their homes. When they use electricity, the source of energy that generates less emissions, they face a positive price of £137 per tonne of CO2e. Once again, the response to these incentives is unsurprising. Household emissions only fell by a relatively small amount between 1990 and 2018 because of the continued use of gas for heating and cooking.
Unsurprisingly many commentators have referred to carbon pricing in the UK as a confusing mess and have called for a unified rate across all activities to minimise the costs to the economy. Another important issue is the level at which a new unified rate is set. Some research by the Department for Business, Energy and Industrial Strategy suggests that the figure would have to be set between £122 and £36 per tonne of CO2e in order for the UK to reach its target of net zero emissions by 2050.
A higher unified rate would also create another problem – the distributional impact. Poorer households spend a much greater share of their income on electricity, heating and food and so would be disproportionately affected by the policy. For the policy to be politically acceptable, the government will need to find an effective way to compensate these groups.
- Outline the difference between territorial and consumption emissions.
- Using the concepts of rivalry and excludability, explain why GHGs and the climate change they cause are an example of market failure.
- Discuss the main differences between cap-and trade schemes and carbon emission taxes.
- Explain why a unified carbon price would minimise the costs to the economy of reducing the level of GHG emissions.
- Discuss some of the potential limitations of introducing carbon pricing and explain why some countries are considering the implementation of a Carbon Border Adjustment mechanism.
With the growing recognition of the global climate emergency (see also), attention is being increasingly focused on policies to tackle global warming.
In the October version of its journal, Fiscal Monitor, the IMF argues that carbon taxes can play a major part in meeting the goal of achieving net zero carbon emissions by 2050 or earlier.
As the blog accompanying the journal states:
Global warming has become a clear and present threat. Actions and commitments to date have fallen short. The longer we wait, the greater the loss of life and damage to the world economy. Finance ministers must play a central role to champion and implement fiscal policies to curb climate change. To do so, they should reshape the tax system and fiscal policies to discourage carbon emissions from coal and other polluting fossil fuels.
The effect of a carbon tax on production
The argument is that carbon emissions represent a massive negative externality, where the costs are borne largely by people other than the emitters. Taxes can internalise these externalities. The effect would be to raise the price of carbon-emitting activities and reduce the quantity consumed and hence produced.
The diagram illustrates the argument. It takes the case of carbon emissions from coal-fired electricity generation in a large country. To keep the analysis simple, it is assumed that all electricity in the country is generated from coal-fired power stations and that there are many such power stations, making the market perfectly competitive.
It is assumed that all the benefits from electricity production accrue solely to the consumers of electricity (i.e. there are no external benefits from consumption). Marginal private and marginal social benefits of the production of electricity are thus the same (MPB = MSB). The curve slopes downwards because, with a downward-sloping demand for electricity, higher output results in a lower marginal benefit (diminishing marginal utility).
Competitive market forces, with producers and consumers responding only to private costs and benefits, will result in a market equilibrium at point a in the diagram: i.e. where demand equals supply. The market equilibrium price is P0 while the market equilibrium quantity is Q0. However the presence of external costs in production means that MSC > MPC. In other words, MEC = b – a.
The socially optimal output would be Q* where P = MSB = MSC, achieved at the socially optimal price of P*. This is illustrated at point d and clearly shows how external costs of production in a perfectly competitive market result in overproduction: i.e. Q0 > Q*. From society’s point of view, too much electricity is being produced and consumed.
If a carbon tax of d – c is imposed on the electricity producers, it will now be in producers’ interests to produce at Q*, where their new private marginal costs (including tax) equals their marginal private benefit.
Assessing the benefits of carbon taxes
The diagram shows the direct effect on production of electricity. With widespread carbon taxes, there would be similar direct effects on other industries that emit carbon, and also on consumers, faced with higher fuel prices. In the UK, for example, there are currently higher taxes on high-emissions vehicles than on low-emissions ones.
However, there are other effects of carbon taxes which contribute to the reduction in carbon emissions over the longer term. First, firms will have an incentive to invest in green energy production, such as wind, solar and hydro. Second, it will encourage R&D in green energy technology. Third, consumers will have an incentive to use less electricity by investing in more efficient appliances and home insulation and making an effort to turn off lights, the TV, computers and so on.
People may object to paying more for electricity, gas and motor fuel, but the tax revenues could be invested in cheaper clean public transport, home insulation and public services generally, such as health and education. This could be part of a policy of redistribution, with the tax revenues being spent on alleviating poverty. Alternatively, other taxes could be cut.
The IMF estimates that to restrict global warming to 2°C (a target seen as too modest by many environmentalists), large emitting countries ‘should introduce a carbon tax set to rise quickly to $75 a ton in 2030’.
This would mean household electric bills would go up by 43 per cent cumulatively over the next decade on average – more in countries that still rely heavily on coal in electricity generation, less elsewhere. Gasoline would cost 14 percent more on average.
It gives the example of Sweden, which has a carbon tax of $127 per ton. This has resulted in a 25% reduction in emissions since 1995, while the economy has expanded 75% since then.
Limits of carbon taxes
Although carbon taxes can make a significant contribution to combatting global warming, there are problems with their use.
First, it may be politically popular for governments not to impose them, or raise them, with politicians arguing that they are keen to help ‘struggling motorists’ or poor people ‘struggling to keep their homes warm’. In the UK, successive governments year after year have chosen not to raise road fuel taxes, despite a Fuel Price Escalator (replaced in 2011 by a Fuel Duty Stabiliser) designed to raise fuel taxes each year by more than inflation. Also, governments fear that higher energy prices would raise costs for their country’s industries, thereby damaging exports.
Second, it is difficult to measure the marginal external costs of CO2 emissions, which gives ammunition to those arguing to keep taxes low. In such cases it may be prudent, if politically possible, to set carbon taxes quite high.
Third, they should not be seen as a sufficient policy on their own, but as just part of the solution to global warming. Legislation to prevent high emissions can be another powerful tool to prevent activities that have high carbon emissions. Examples include banning high-emission vehicles; a requirement for coal-fired power stations and carbon emitting factories to install CO2 scrubbers (filters); and tougher planning regulations for factories that emit carbon. Education to encourage people to cut their own personal use of fossil fuels is another powerful means of influencing behaviour.
A cap-and-trade system, such as the European Emissions Trading Scheme would be an alternative means of cutting carbon efficiently. It involves setting quotas for emissions and allowing firms which manage to cut emissions to sell their surplus permits to less efficient firms. This puts a price pressure on firms to be more efficient. But the quotas (the ‘cap’) must be sufficiently tight if emissions are going to be cut to desired levels.
But, despite being just one possible policy, carbon taxes can make a significant contribution to combatting global warming.
- Fiscal Policies to Curb Climate Change
IMF blog, Vitor Gaspar, Paolo Mauro, Ian Parry and Catherine Pattillo (10/10/19)
- Energy bills will have to rise sharply to avoid climate crisis, says IMF
The Guardian, Larry Elliott (10/10/19)
- Huge global carbon tax hike needed in next 10 years to head off climate disaster, says IMF
Independent, Chris Mooney and Andrew Freedman (11/10/19)
- World urgently needs to quicken steps to reduce global warming – IMF
Reuters, Lindsay Dunsmuir (10/10/19)
- The Case for a Goldilocks Carbon Tax
Forbes, Roger Pielke (13/9/19)
- The world needs a massive carbon tax in just 10 years to limit climate change, IMF says
Washington Post, Chris Mooney and Andrew Freedman (10/10/19)
- People like the idea of a carbon tax – if the money is put to good use
New Scientist, Michael Le Page (18/9/19)
- The IMF thinks carbon taxes will stop the climate crisis. That’s a terrible idea.
The Guardian, Kate Aronoff (12/10/19)
- Firms ignoring climate crisis will go bankrupt, says Mark Carney
The Guardian, Damian Carrington (13/10/19)
- How central banks can tackle climate change
Financial Times, The editorial board (31/10/19)
- World Economic Forum: Climate change action needed to avoid societal ‘collapse’ says minister
The National, UAE, Anna Zacharias (3/11/19)
- Riots and trade wars: Why carbon taxes will not solve climate crisis
Recharge, Leigh Collins (31/10/19) (Part 1)
- The plethora of effective alternatives to carbon pricing
Recharge, Leigh Collins (31/10/19) (Part 2)
- Are these the real reasons why Big Oil wants a carbon tax?
Recharge, Leigh Collins (31/10/19) (Part 3)
- Do we need carbon taxes in an era of cheap renewables?
Recharge, Leigh Collins (31/10/19) (Part 4)
- How to Mitigate Climate Change
IMF Fiscal Monitor, Ian Parry (team leader), Thomas Baunsgaard, William Gbohoui, Raphael Lam, Victor Mylonas, Mehdi Raissi, Alpa Shah and Baoping Shang (October 2019)
- Draw a diagram to show how subsidies can lead to the optimum output of green energy.
- What are the political problems in introducing or raising carbon taxes? Examine possible solutions to these problems
- Choose two policies for reducing carbon emissions other than using carbon taxes? Compare their effectiveness with carbon taxes.
- How is game theory relevant to getting international agreement on cutting greenhouse gas emissions? Why is there likely to be a prisoners’ dilemma problem in reaching and sticking to such agreements? How might the problem of a prisoners’ dilemma be overcome in such circumstances?
The Governor of California, Jerry Brown, has issued an executive order to cut greenhouse gas emissions 40% from 1990 levels by 2030 (a 44% cut on 2012 levels). This matches the target set by the EU. It is tougher than that of the US administration, which has set a target of reducing emissions in the range of 26 to 28 percent below 2005 levels by 2025.
The former Governor of California, Arnold Schwarzenegger, had previously set a target of reducing emissions 80% below 1990 levels by 2050. Brown’s new target can be seen as an interim step toward meeting that longer-term goal.
There are several means by which it is planned to meet the Californian targets. These include:
a focus on zero- and near-zero technologies for moving freight, continued investment in renewables including solar roofs and distributed generation, greater use of low-carbon fuels including electricity and hydrogen, stronger efforts to reduce emissions of short-lived climate pollutants (methane, black carbon and fluorinated gases), and further efforts to create liveable, walkable communities and expansion of mass transit and other alternatives to travelling by car.
Some of these will be achieved through legislation, after consultations with various stakeholders. But a crucial element in driving down emissions is the California’s carbon trading scheme. This is a cap-and-trade system, similar to the EU’s Emissions Trading Scheme.
The cap-and-trade rules came into effect on January 1, 2013 and apply to large electric power plants and large industrial plants. In 2015, they will extend to fuel distributors (including distributors of heating and transportation fuels). At that stage, the program will encompass around 360 businesses throughout California and nearly 85 percent of the state’s total greenhouse gas emissions.
Under a cap-and-trade system, companies must hold enough emission allowances to cover their emissions, and are free to buy and sell allowances on the open market. California held its first auction of greenhouse gas allowances on November 14, 2012. This marked the beginning of the first greenhouse gas cap-and-trade program in the United States since the group of nine Northeastern states in the Regional Greenhouse Gas Initiative (RGGI), a greenhouse gas cap-and-trade program for power plants, held its first auction in 2008.
Since January 2014, the Californian cap-and-trade scheme has been linked to that of Quebec in Canada and discussions are under way to link it with Ontario too. Also California is working with other west-coast states/provinces, Oregon, Washington and British Columbia, to develop a co-ordinated approach to greenhouse gas reductions
To achieve sufficient reductions in emissions, it is not enough merely to have a cap-and-trade system which, through trading, encourages an efficient reduction in emissions. It is important to set the cap tight enough to achieve the targeted reductions and to ensure that the cap is enforced.
In California, emissions allowances are distributed by a mix of free allocation and quarterly auctions. Free allocations account for around 90% of the allocations, but this percentage will decrease over time. The total allowances will decline (i.e. the cap will be tightened) by 3% per year from 2015 to 2020.
At present the system applies to electric power plants, industrial plants and fuel distributors that emit, or are responsible for emissions of, 25,000 metric tons of carbon dioxide equivalent (CO2e) per year or more. The greenhouse gases covered are the six covered by the Kyoto Protocol ((CO2, CH4, N2O, HFCs, PFCs, SF6), plus NF3 and other fluoridated greenhouse gases.
California governor orders aggressive greenhouse gas cuts by 2030 Reuters. Rory Carroll (29/4/15)
California’s greenhouse gas emission targets are getting tougher Los Angeles Times, Chris Megerian and Michael Finnegan (29/4/15)
Jerry Brown sets aggressive California climate goal The Desert Sun, Sammy Roth (29/4/15)
California’s Brown Seeks Nation-Leading Greenhouse Gas Cuts Bloomberg, Michael B Marois (29/4/15)
California sets tough new targets to cut emissions BBC News, (29/4/15)
California’s New Greenhouse Gas Emissions Target Puts Obama’s To Shame New Republic, Rebecca Leber (29/4/15)
Governor Brown Announces New Statewide Climate Pollution Limit in 2030 Switchboard, Alex Jackson (29/4/15)
Cap-and-trade comes to Orego Watchdog, Chana Cox (29/4/15)
Cap and trade explained: What Ontario’s shift on emissions will mean The Globe and Mail, Adrian Morrow (13/4/15)
California’s Forests Have Become Climate Polluters Climate Central, John Upton (29/4/15)
States Can Learn from Each Other On Carbon Pricing The Energy Collective, Kyle Aarons (28/4/15)
Governor Brown Establishes Most Ambitious Greenhouse Gas Reduction Target in North America Office of Edmund G. Brown Jr. (29/4/15)
Frequently Asked Questions about Executive Order B-30-15: 2030 Carbon Target and Adaptation California Environmental Protection Agency: Air Resources Board (29/4/15)
Californian cap-and-trade scheme
Cap-and-Trade Program California Environmental Protection Agency: Air Resources Board (29/4/15)
California Cap and Trade Center for Climate and Energy Solutions (January 2014)
- Explain how a system of cap-and-trade, such as the Californian system and the ETS in the EU, works.
- Why does a cap-and-trade system lead to an efficient level of emissions reduction?
- How can a joint system, such as that between California and Quebec, work? Is it important to achieve the same percentage pollution reduction in both countries?
- What are countries coming to the United Nations Climate Change conference in Paris in November 2015 required to have communicated in advance?
- How might game theory be relevant to the negotiations in Paris? Are the pre-requirements on countries a good idea to tackle some of the ‘gaming’ problems that could occur?
- Why is a cap-and-trade system insufficient to tackle climate change? What other measures are required?
At the end of two weeks of often acrimonious wrangling between representatives from 193 countries, an agreement – of sorts – was reached at the climate change summit in Copenhagen. What was this agreement? It was an ‘accord’ brokered by the USA, China, India, Brazil and South Africa.
This Copenhagen Accord contains three elements. The first is a recognition of the need to prevent global temperatures rising by more than 2 degrees Celsius above pre-industrial levels. The second is a commitment by developed countries to give $30bn of aid between 2010 and 2012 to developing countries for investment in green technology and to mitigate the effects of climate change. In addition, a goal was set of providing $100bn a year by 2020. The third is for rich countries to give pledges on emissions reductions and for developing countries to give pledges on reducing emissions increases. Developed countries’ pledges will be scrutinised by the UN Framework Convention on Climate Change, while developing countries will merely be required to submit reports on their progress in meeting their pledges.
But this is only an accord. It has no legal status and was merely ‘recognised’ by the countries at the conference. What is more, the target of limiting temperature rises to 2C does not contain a date by which temperature rises should peak. Also, as countries are not required to submit targets for emissions until February 2010, it is not clear how these targets will be kept low enough to meet the temperature target and there is no identification of penalites that would apply to countries not meeting their pledges.
Not surprisingly, reactions around the world have been mixed. The following podcasts and articles look at these reactions and at the economic mechanisms that will be required to meet the 2C limit
Podcasts and videos
Recriminations after Copenhagen summit (video) BBC News, David Loyn (21/12/09)
Copenhagen special: Climate change talks end in failure Guardian podcast (19/12/09)
Where do we go after Copenhagen? BBC Today Programme (21/12/09)
What was agreed and left unfinished in U.N. climate deal Reuters of India Factbox (20/12/09)
Copenhagen deal: Key points BBC News (19/12/09)
Copenhagen deal reaction in quotes BBC News (19/12/09)
Copenhagen climate summit fails green investors BBC News, Damian Kahya (22/12/09)
Why did Copenhagen fail to deliver a climate deal? BBC News (22/12/09)
Copenhagen climate accord: Key issues BBC News (19/12/09)
Harrabin’s Notes: After Copenhagen BBC News, Roger Harrabin (19/12/09)
Copenhagen climate conference: Who is going to save the planet now? Telegraph, Louise Gray (21/12/09)
Copenhagen’s One Real Accomplishment: Getting Some Money Flowing New York Times, James Kanter (20/12/09)
Copenhagen climate summit: plan for EU to police countries’ emissions (including video) Telegraph, James Kirkup, and Louise Gray (19/12/09)
The road from Copenhagen Guardian, Ed Miliband (UK Secretary of State for Energy and Climate Change) (20/12/09)
Carbon Prices Tumble After ‘Modest’ Climate Deal Bloomberg, Mathew Carr and Ewa Krukowska (21/12/09)
Copenhagen deal causes EU carbon price fall BBC News (21/12/09)
Have the hopes of environmentalists been dashed? Financial Times, Clive Cookson (21/12/09)
EU reflects on climate ‘disaster’ Financial Times, Joshua Chaffinin (22/12/09)
China not to blame on climate China Daily, Zhang Jin (23/12/09)
Selling a low-carbon life just got harder Times Online, Jonathon Porritt (21/12/09)
Better than nothing The Economist (19/12/09)
Copenhagen has given us the chance to face climate change with honesty Observer, James Hansen (27/12/09)
- What incentives exist for countries to agree to tough pledges to reduce emissions?
- Was the very limited nature of the Copenhagen Accord a Nash equilibrium? Explain.
- Is the carbon price a good indicator of the effectiveness of measures to curb emissions?
- Must any agreement have verifiable targets for each country of the world if it is to be successful in curbing carbon emissions?
- Is a cap-and-trade system the best means of achieving emissions reductions? Explain.
In the run-up to the United Nations climate Change conference in Copenhagen from 7 to 18 December, many countries have been setting out their preliminary positions. The conference aims to set the terms for the agreement that will succeed the Kyoto Protocol in 2012.
Senior scientists, economists and politicians have been warning about the dire necessity of reaching a comprehensive agreement. One such economist is Sir Nicholas Stern. He argues that the EU should impose a unilateral cut in greenhouse gas emissions of 30% from 1990 levels by 2020, irrespective of the any agreement in Copenhagen. The EU has pledged to increase its targeted cut from 20% to 30% only if substantive progress is made at the talks.
Other countries have set out their preliminary positions. China has offered to reduce its carbon intensity by 40% (i.e. the proportion of carbon emissions to GDP); the USA has offered to reduce emissions by 17% by 2020 compared with 2005 levels; and India has offered to reduce its carbon intensity by 24% over the same period.
However, as the Washington Post article below states, “During a weekend meeting, India, along with China, Brazil, South Africa and Sudan, decided it would not agree to legally binding emission cuts, international verification of reductions without foreign funding and technology, and imposition of trade barriers in the name of climate change.”
Meanwhile the news from Australia has come as a blow to those seeking to extend tradable permit schemes around the world. The Australian senate has rejected a bill to set up an Emissions Trading Scheme (ETS), designed to cut Australia’s carbon emissions by up to 25% below 2000 levels by 2020.
Copenhagen climate talks: Main issues Independent (30/11/09)
Factfile on UNFCCC, Kyoto Protocol, Copenhagen talks Independent (30/11/09)
Copenhagen summit: Is there any real chance of averting the climate crisis? Observer, James Hansen (29/11/09)
A heated debate Economist (26/11/09)
Getting warmer Economist (3/12/09)
Is it worth it? Economist (3/12/09)
Good policy, and bad Economist (3/12/09)
The Carbon Economy Economist (3/12/09)
Copenhagen climate summit: 50/50 chance of stopping catastrophe, Lord Stern says Telegraph (1/12/09)
UK Economist: Climate Skeptics are Confused U.S.News, Meera Selva (1/12/09)
Growing Scientific Consensus on Climate Change Ahead of Copenhagen Conference Voice of America, Michael Bowman (1/12/09)
EU ‘should cut emissions by 30%’ BBC News, Roger Harrabin (1/12/09)
Stern says Copenhagen could still save world Environmental Data Interactive Exchange (1/12/09)
Moves by U.S., China induce India to do its bit on climate Washington Post, Rama Lakshmi (2/12/09)
Why do climate deniers hold sway in Australia? Guardian, Fred Pearce (1/12/09)
Australian Senate defeats carbon trading bill Guardian, Toni O’Loughlin (2/12/09)
Failed CPRS ‘may lead to better plan’ Sydney Morning Herald (2/12/09)
Australia carbon laws fail, election possible Reuters, Rob Taylor (2/12/09)
Australian Senate rejects Kevin Rudd’s climate plan BBC News (2/12/09)
The following is the official conference site:
United Nations Climate Change Conference Dec 7–Dec 18 2009
- Why cannot tackling global warming be left totally to the market?
- To what extent can the market provide part of the solution to global warming?
- How can a cap-and-trade system (i.e. tradable permits) be used to achieve (a) emissions reductions; (b) an efficient way of achieving such reductions?
- Why could the atmosphere be described as a ‘global commons’? Does it have either or both of the features of non-excludability and non-rivalry (which are both features of a public good)?
- To what extent are climate change talks a prisoner’s dilemma game? How may the Nash equilibrium of no deal, or an unenforceable deal, be avoided?