Tag: external costs

If it costs to dispose of waste, there is the danger that people may resort to fly-tipping – the illegal dumping of waste in the countryside or on the streets. But several local authorities have indeed been charging for the disposal of building/DIY waste, with the inevitable consequences of huge quantities of dumped rubbish.

Apart from being an eyesore and damaging the environment, fly-tipped waste can be a health hazard, often containing toxic materials, such as asbestos and chemicals. According to the UK government, in 2020/21 there were over 60 000 incidents of fly-tipping of construction, demolition and excavation material, costing an estimated £392 million. In addition, people leave black bags of household waste and single items, such as mattresses, on the roadside.

The external costs are considerably greater than the benefits to those doing the dumping, but because the costs are largely external, people are encouraged to fly-tip, especially if they think that they are unlikely to be caught. Many householders are happy to pay low rates to have their DIY waste disposed of and ‘ask no questions’ about what will happen to it.

It is clearly socially efficient to stop fly-tipping. One solution is to enforce the law more rigorously and to introduce stiffer penalties. Increasingly, local authorities and private landowners are installing CCTV cameras to identify people doing the tipping. To be effective, the cameras must be out of reach. Also, the police must then follow up any cases and arrest and charge the culprits.

An alternative is to provide free disposal at council tips. The UK government has launched a consultation on a proposal to prevent local authorities from charging for the disposal of DIY waste. This still involves an externality in that the costs of disposal are not being borne by the person creating the waste, but clearly the size of the negative externality is considerably less than if the waste had been fly-tipped.

Selected local authorities can apply for new grants totalling £450 000 to help fund the provision of free DIY waste disposal and to install systems, such as CCTV and automatic number-plate recognition, to catch fly-tippers in action.

Devising policies to reduce externalities often involves understanding the incentive mechanisms which encourage people to engage in such activities in the first place and then making it in people’s interests not to engage in them in the future.



Government publications


  1. Draw a diagram to illustrate how the consumption of products with large negative externalities is considerably above the socially efficient level.
  2. Compare the relative advantages and disadvantages of the various policy alternatives to tackle fly-tipping that are discussed in the articles.
  3. Are there any ‘nudges’ that could be used to prevent fly-tipping?

Do you want to get drunk this festive season in the most tax efficient way: i.e. minimise the amount of tax you pay for the volume of alcohol that you drink? Do tax rates vary or are all alcoholic drinks taxed in the same or similar way?

The UK government imposes two different types of tax on alcohol. One is a specific or fixed tax per unit, referred to as excise duty or excise tax. This varies depending on the type of alcohol and is the focus of this blog. The other is VAT, which is 20% of the price for all alcoholic drinks. The price on which VAT is based includes the impact of the excise tax.

How does the implementation of excise tax differ between alcoholic drinks? Both the tax rate itself and the unit of output on which it is based vary: i.e. the volume of liquid vs the volume of pure alcohol within the liquid.

For example, with lager, beer and spirits the excise tax depends on the units of alcohol in the drink rather than the number of litres. The tax works in the following way. It is based on the alcohol by volume or ABV of the lager, beer or spirit. This is often displayed on the bottle or can. ABV is the percentage of the drink that is pure alcohol. Therefore, if a one-litre bottle of lager has an ABV of 1%, then 10ml of the bottle contains pure alcohol. Ten millilitres of pure alcohol is one unit of alcohol. If a one litre bottle of lager had an ABV of 5% it contains 5 units of alcohol.

Excise duties on spirits are the simplest of all the alcohol taxes. The rate for 2017/18 is 28.74p for each percentage of ABV or unit of alcohol in a one-litre bottle. Most spirits have an ABV of 40%. This means that there are 40 units of alcohol in a litre bottle and the excise tax payable on that bottle is £11.50 (40 × 28.74p). If a litre bottle had an ABV of 57%, such as Woods Navy Rum, then the excise tax would be or £16.38 (57 × 28.74p). Although the volume of liquid is the same in each case, the excise tax has increased by £4.88 because the alcohol content has increased.

For cider and wine the system is quite different. Within certain bands of alcoholic strength, the excise duty is based on the volume of the drink rather than by its ABV. For example, the excise tax on a litre of cider with an ABV of between 1.2% and 7.5% is 40.38p. This has the effect of reducing the tax rate per unit of alcohol as the alcoholic content of the cider increases (up to a limit of 7.5%). For example, the rate of excise tax per unit of alcohol for a litre bottle of cider with an ABV of 2% is 20.19p (40.38/2) whereas for a litre bottle of cider with an ABV of 7.5% it is just 5.39p (40.38/7.5). Wine is taxed in a similar way. A litre of wine with an ABV of between 5.5% and 15% is taxed at 288.65p per litre.

The excise tax rates per unit of alcohol for different drinks are illustrated below.

Excise tax per
unit of alcohol

The table clearly shows that cider with an ABV of 7.5 per cent is by far the most tax effective way of consuming alcohol.

Although this blog is a rather light-hearted look at excise tax, it does help to illustrate the strange anomalies of the system used in the UK. Research by the Institute for Fiscal Studies (IFS) has indicated that heavier drinkers are more likely to switch between different alcoholic products in response to price changes. They also tend to drink products with more units of alcohol in them: i.e. spirits such as whisky and gin. For these reasons, the IFS has suggested that the excise tax rates on cider and spirits should be increased.

In the November budget, the Chancellor announced plans to introduce a new excise tax rate on still cider with an ABV of between 6.9% and 7.5%.

The excise taxes on cider and wine are based on the volume of liquid because of the European Community Directive 92/84/EEC. It will be interesting to see if the government changes this system to one based on alcohol content once the UK had left the European Union.


Budget 2017 – Why is white cider being taxed more? BBC News (22/11/17)
Is it time for a flat tax on alcohol – health campaigners can drink to that The Telegraph, Christopher Snowdon (15/2/17)
Traditional cider makers say tax on strong brands will hurt their business The Guardian, Rob Davies (22/11/17)
Minimum price would increase cost of 70% of alcohol BBC News (15/12/17)
Designing alcohol taxes IFS, Kate Smith (24/4/17) .


  1. Explain the difference between an ad valorem tax and a specific tax.
  2. Illustrate the impact of an ad valorem tax and a specific tax on a demand and supply diagram.
  3. What is the excise tax rate per unit of alcohol on a litre bottle of cider with an ABV of 6%?
  4. What is the economic rationale for imposing excise tax on alcohol?
  5. How will the external costs of consuming alcohol differ from those of smoking cigarettes? Draw a marginal external cost of consumption curve for both products to illustrate the difference.
  6. Compare the impact of increasing excise tax rates on cider and spirits with introducing a minimum unit price for alcohol.
  7. In April 2012 the government in England and Wales imposed a ban on ‘below cost’ pricing of alcohol. Explain how this policy works and what impact you think it has had.

Many politicians throughout the world,
not just on the centre and left, are arguing for increased spending on infrastructure. This was one of the key proposals of Donald Trump during his election campaign. In his election manifesto he pledged to “Transform America’s crumbling infrastructure into a golden opportunity for accelerated economic growth and more rapid productivity gains”.

Increased spending on inffrastructure has both demand- and supply-side effects.

Unless matched by cuts elsewhere, such spending will increase aggregate demand and could have a high multiplier effect if most of the inputs are domestic. Also there could be accelerator effects as the projects may stimulate private investment.

On the supply side, well-targeted infrastructure spending can directly increase productivity and cut costs of logistics and communications.

The combination of the demand- and supply-side effects could increase both potential and actual output and reduce unemployment.

So, if infrastructure projects can have such beneficial effects, why are politicians often so reluctant to give them the go-ahead?

Part of the problem is one of timing. The costs occur in the short run. These include demolition, construction and disruption. The direct benefits occur in the longer term, once the project is complete. And for complex projects this may be many years hence. It is true that demand-side benefits start to occur once construction has begun, but these benefits are widely dispersed and not easy to identify directly with the project.

Then there is the problem of externalities. The external costs of projects may include environmental costs and costs to local residents. This can lead to protests, public hearings and the need for detailed cost–benefit analysis. This can delay or even prevent projects from occurring.

The external benefits are to non-users of the project, such as a new bridge or bypass reducing congestion for users of existing routes. These make the private construction of many projects unprofitable, except with public subsidies or with public–private partnerships. So there does need to be a macroeconomic policy that favours publicly-funded infrastructure projects.

One type of investment that is less disruptive and can have shorter-term benefits is maintenance investment. Maintenance expenditure can avoid much more costly rebuilding expenditure later on. But this is often the first type of expenditure to be cut when public-sector budgets as squeezed, whether at the local or national level.

The problem of lack of infrastructure investment is very much a political problem. The politicians who give the go-ahead to such projects, such as high-speed rail, come in for criticisms from those bearing the short-run costs but they are gone from office once the benefits start to occur. They get the criticism but not the praise.


Are big infrastructure projects castles in the air or bridges to nowhere? The Economist, Buttonwood’s notebook (16/1/17)
Trump’s plans to rebuild America are misguided and harmful. This is how we should do it. The Washington Post, Lawrence H. Summers (17/1/17)


  1. Identify the types of externality from (a) a new high-speed rail line, (b) new hospitals.
  2. How is discounting relevant to decisions about public-sector projects?
  3. Why are governments often unwilling to undertake (a) new infrastructure projects, (b) maintenance projects?
  4. Is a programme of infrastructure investment necessarily a Keynesian policy?
  5. What accelerator effects would you expect from infrastructure investment?
  6. Explain the difference between the ‘spill-out’ and ‘pull-in’ effects of different types of public investments in a specific location. Is it possible for a project to have both effects?
  7. What answer would you give to the teacher who asked the following question of US Treasury Secretary, Larry Summers? “The paint is chipping off the walls of this school, not off the walls at McDonald’s or the movie theatre. So why should the kids believe this society thinks their education is the most important thing?”
  8. What is the ‘bridge to nowhere’ problem? Why does it occur and what are the solutions to it?
  9. Why is the ‘castles in the air’ element of private projects during a boom an example of the fallacy of composition?

Australia held a general election on 2 July 2016. The Liberal/National coalition narrowly won in the House of Representatives, gaining a substantially reduced majority of 77 of the 150 seats, to Labor’s 68 and other parties’ 5 seats. One campaign issue for all parties was the destruction of the Great Barrier Reef, which is seen as an environmental disaster. Each party had proposals for tackling the problem and we examine some of them here.

The Great Barrier Reef is the largest coral reef in the world. As the BBC’s iWonder guide states:

One of the world’s seven natural wonders, the Great Barrier Reef contains some 900 islands and 3000 smaller reefs. It is larger than the UK, the Netherlands and Switzerland combined, home to around 10% of the world’s marine fish, over 200 bird species and countless other animals, including turtles and dolphins.

But this iconic Reef system is facing unprecedented threats. Together with governments, scientists are playing a key role in the battle to preserve this vulnerable ecosystem before it’s too late.

The Reef is 2300km long. In the northern third, around half of the coral is dead. Few tourists see this, as they tend to dive in the southern third, which, being cooler, is less affected.

The bleaching and destruction of coral reefs has a number of causes. These include: rising water temperatures, generally from global warming and more extreme El Niño events (rising warm waters that periodically spread across the Pacific); pollution, including that from coal mining, industrial effluent and run-off of pesticides, herbicides, fertilisers and sediment from farming, leading to acidification of waters; more frequent and more violent cyclones; rapidly expanding numbers of coral-eating Crown of Thorns starfish; and over fishing of some species of fish, leading to knock-on effects on ecosystems.

The Barrier Reef and the oceans and atmosphere around it can be regarded as a common resource. The warming of the atmosphere and the oceans, and the destruction of the reef and the wildlife on it, are examples of the ‘tragedy of the commons’. With no-one owning these resources, they are likely to be overused and abused. Put another way, these activities cause negative externalities, which do not appear as costs to the polluters and despoilers, but are still costs to all who treasure the reef. And, from a non-human perspective, it is a cost to the planet and its biodiversity. What is in the private interests of the abusers is not in the social or environmental interest.

The Australian government had sought to downplay the extent of the problem, afraid of deterring tourists – a valuable source of revenue – and under pressure from the coal and farming industries. Nevertheless, in the run-up to the election, the destruction of the Reef and what to do about it became a major debating point between the parties.

The Coalition government has pledged A$1bn for a new Reef fund, which will be dedicated to tackling climate change and water quality.

The fund will also help coastal sewage treatment plants to reduce ocean outfalls with efficient pumps, biogas electricity generation and next-generation waste water treatment. Improving water quality will enhance the Reef’s resilience to climate change, coral bleaching and outbreaks of the destructive crown of thorns starfish.

But how much difference the fund can make with the money it will have is not clear.

The Labor Party pledged to follow every recommendation in the Great Barrier Reef Water Science Taskforce’s Final Report, released in May, and to pass laws to prevent farm pollution flowing into the waters around the Reef and to have a more rapid shift towards renewable energy.

The Green Party goes the furthest. In addition to the Labor Party’s proposals, it wants to impose taxes on coal firms equal to the cost of the damage they are causing. The tax revenues would be paid into a multi-billion dollar fund. This would then be spent on measures to rescue the Reef, invest in clean energy projects, stop damaging industrial development, improve farm management and stop polluted run-off into the Reef catchment area by investing in water systems.

Promises at the time of an election are all well and good. Just how much will be done by the re-elected Coalition government remains to be seen.

Interactive Videos and presentations
David Attenborough’s Great Barrier Reef: an Interactive Journey, Atlantic Productions, David Attenborough (2015)
Global Warming – the greatest market failure Prezi, Yvonne Cheng (5/12/12)


The Great Barrier Reef: a catastrophe laid bare The Guardian, Michael Slezak (7/6/16)
The Guardian view on the Great Barrier Reef: the crisis they prefer to downplay The Guardian (7/6/16)
Fight to save Great Barrier Reef could cost billions, secret government modelling estimates ABC News, Mark Willacy (2/6/16)
Great Barrier Reef: government must choose which parts to save, says expert The Guardian, Joshua Robertson (8/7/16)
This election, what hope is there for the Great Barrier Reef? The Guardian, Michael Slezak (1/7/16)
Coalition will protect Great Barrier Reef with $1bn fund, says PM The Guardian, Gareth Hutchens (12/6/16)
Great Barrier Reef election explainer: how do the parties compare? The Guardian, Michael Slezak (2/6/16)
Five things we can do right now to save the Great Barrier Reef The Guardian, John Pandolfi (13/6/16)
We’ve scored the parties on the Reef My Sunshine Coast, Australian Marine Conservation Society (29/6/16)
Our Most Iconic Places Are Under Dire Threat From Climate Change Huffington Post, Nick Visser (26/5/16)
There are bright spots among the world’s coral reefs – the challenge is to learn from them The Conversation, Australia, Joshua Cinner (21/7/16)


  1. Explain what is meant by the Tragedy of the Commons. Is all pollution damage an example of this?
  2. What can the Australian government do to internalise the external costs to the Great Barrier Reef from (a) farming; (b) mining; (c) global warming?
  3. Why is it difficult to reach international agreement on tackling climte change? What insights can game theory provide for understanding the difficulties?
  4. What are the recommendations in the Final Report of the Great Barrier Reef Water Science Taskforce? What mix of tools does it suggest?
  5. What are the relative advantages and disadvantages of taxation, laws and regulations, public investment, education and international negotiation as policy instruments to protect the Reef?