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Posts Tagged ‘congestion’

Do bus lanes increase congestion?

Demand and supply analysis can be applied to a multitude of markets. When there is a disequilibrium in a market, prices will tend to adjust to eliminate any shortage or surplus. But, what of road space? There is a demand and a supply of road space and when there are too many cars for the road space available, congestion is the consequence.

When an additional car enters the road network, there is a cost and a benefit to the driver. However, there are not only costs/benefits to the driver, but there are also costs/benefits to other road-users. When one car drives on the M25 it adds to the number of cars on the road. Once we reach the point where there are too many cars given the road space and thus the flow of cars per minute begins to fall, congestion starts to build up. There is a negative externality involved here – the actions of one person (the driver) impose an additional cost on other drivers (the congestion). It takes every other road user a little bit of extra time to get from A to B the more cars there are on the road.

Congestion is a problem in many parts of the country and various solutions have been suggested. Policies to reduce demand will help the congestion problem by reducing the number of cars on the road. Numerous strategies have been tried, such as restrictions on parking; improvements in public transport; an integrated transport policy; higher parking charges; work place parking levies; higher taxes on petrol, higher car taxes and congestion charging schemes.

Alternatively, building more roads will directly increase the supply of road space, but this can (and has) simply led to more cars using the additional road space and thus the problem of congestion remains. Bus/taxi lanes are in use across the country and allow the users of public transport to benefit from faster journey times, thus encouraging them to forgo their cars and use buses. However, does this add to the congestion for other people?

In Liverpool, a nine month trial is taking place, where bus lanes will be removed to find out if they have a positive effect on reducing congestion. By increasing the amount of road space available to all road users, Liverpool City Council will be able to see if directly increasing the supply of road space will help to meet the existing demand. The possibility, however, is that by increasing the supply of road space, more individuals will choose to use their cars, thus fuelling demand. Many argue that this trial is a step backwards and will add to congestion, reduce the appeal of travelling by bus and impose further costs on the environment. The following articles consider the debate surrounding congestion.

Liverpool City Council will scrap bus lanes for nine months BBC News (27/9/13)
Liverpool bus lanes plan criticised by government Liverpool Daily Post (9/10/13)
Calls for single 30% income tax rate BBC News (21/5/12)
Liverpool scraps bus lanes in trial BBC News (including video) (21/10/13)
Government warning over Liverpool council plans to axe bus lanes in the city Liverpool Echo (9/10/13)


  1. Explain why congestion is a negative externality. What other externalities exist with regard to car usage?
  2. Using a diagram, show the point at which congestion occurs and explain why there is a difference between the marginal private and marginal social cost.
  3. What will happen to the difference between the marginal private and social cost curves before and after congestion sets in?
  4. Think about the different solutions to the problem of congestion. In each case, explain whether it is a demand-side or supply-side solution and how it will aim to combat congestion. You should also consider whether it is a short or long term solution and how feasible it actually is.
  5. How will the abolition of bus lanes aim to reduce congestion?
  6. There are supporters for bus lanes and supporters for the abolition of them. Justify the arguments on each side of the debate. You should consider the wider implications as well as the impact on congestion.
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The road ahead

The Office for Budget Responsibility has said that the UK Treasury will face a shortfall of £13bn in motoring taxes within a decade. Although car usage continues to rise putting increasing pressure on the road infrastructure, the greener and more fuel efficient cars being produced are driving down the tax revenues generated from motoring.

A report by the IFS has put forward the case for replacing the existing system of taxes on cars and fuel by a new road charging system. If no such change occurs, the IFS has forecast that with more electric cars and hence lower revenues raised from fuel and vehicle excise duties, the shortfall facing the Treasury would require an increase in fuel duty of some 50%. Instead of this, the solution could be to charge individuals for every mile of road they use, with the ‘price’ varying depending on the degree of congestion. For example, at peak times the price would be higher, where as for those in the countryside where roads are traditionally much quieter, charges would be lower. The IFS said:

‘Such a move would generate substantial economic efficiency gains from reduced congestion, reduce the tax levied on the majority of miles driven, leave many (particularly rural) motorists better off, and provide a stable long-term footing for motoring taxes without necessarily raising net additional revenue from drivers.’

Government policy across the world has been increasingly focused on climate change, with targets for emissions reductions being somewhat ambitious. However, many car manufactures who were told to reduce emissions significantly are on the way to meeting these targets and this success is a key factor contributing towards this new road ‘crisis’ that could soon be facing the government. The following articles consider the possibility of a road charging scheme.

The road ahead for motoring taxes? Institute of Fiscal Studies (link to full report at the bottom of the page) (May 2012)

Compelling case for UK road charging, IFS study says BBC News (15/5/12)
Fears tax shortfall may lead to road tolls Sky News (15/5/12)
Who’s going to pay to update Britain’s infrastructure? Guardian Business Blog (15/5/12)
Motoring taxes: a future headache for the Chancellor Channel 4 News (15/5/12)
For whom the toll bills – less traffic hurts M6 toll road owner Guardian, Ian Griffiths and Dan Milmo (14/5/12)
Charge motorists per mile, says IFS Independent, Nigel Morris (15/5/12)
Green cars to drive down tax receipts Financial Times, Mark Odell and John Reed (15/5/12)


  1. Illustrate the effect of a tax being imposed on petrol. What happens to the equilibrium price and quantity?
  2. Despite fuel duty pushing up the price of petrol, why has there been such a small decline in the quantity of petrol individuals use?
  3. Evaluate the case for and against a road charging scheme.
  4. Why are tax revenues from motoring expected to decline over the next decade?
  5. Climate change has become an increasingly important focus of government policy. To what extent is the current road ‘crisis’ a positive sign that policies to tackle climate change are working?
  6. If a road charging scheme went ahead and prices were varied depending on traffic, time etc, what name would you give to this strategy?
  7. Why would it be possible to charge a higher price at peak times and a lower price for cars using country roads?
  8. Is there an argument for privatising the road network? Is it even possible?
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The car of the future?

Market failure occurs when the free market fails to deliver an efficient allocation of resources. Pollution by cars is a prime example of a negative externality or an external cost. We pay road tax and face high tax rates on petrol, but another form of government intervention is due to come into effect. From the 1st January 2011, nine models of electric car will be eligible for grants of up to £5000 (although only three models will be immediately available). By subsidising certain electric cars, the government is aiming to give people an incentive to switch to these so-called more environmentally friendly cars, as they will now be cheaper.

There are concerns, however, that generating the electricity to charge these cars still emits carbon dioxide. The Transport Secretary, Philip Hammond, said:

There’s no point in switching the car fleet to running on electricity if the electricity emits vast amounts of carbon dioxide.

So is the electric car the car of the future?

Nine electric cars will be eligible for subsidies BBC News (14/120/10)
Cash grants for environmentally friendly cars announced Telegraph (14/12/10)
£850,000 to kickstart use of electric cars in NI BBC News (14/12/10)
UK names nine electric cars eligible for subsidy Reuters (14/20/10)


  1. What is the purpose of a subsidy? Using a diagram explain how it will work and what the impact should be.
  2. Why is pollution an example of a market failure? Illustrate this on a diagram.
  3. Why could electric cars also be an example of a market failure? Illustrate this on a diagram.
  4. How will the subsidy aim to encourage more firms to produce electric cars and also more consumers to buy them?
  5. Is there an argument for increased investment in technology to produce electric cars more cheaply and more effectively?
  6. Why is there such a high demand for car usage?
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Pay-as-you-drive moves a step closer

The issue of road pricing has been simmering in the background of the environmental debate for many years and has, this month, gained greater prominence with the publication of a draft version of the Road Transport Bill that will allow local authorities to run pay-as-you-drive trials in their local areas. A number of local authorities will be interested, though all will be wary of the policy given the recent petition on the Downing Street website against road pricing that got nearly two million signatures! London Mayor, Ken Livingstone, has meanwhile extended the reach of the London congestion charge with his plans to create a low emission zone (LEZ) in the capital and charge more for older, and therefore dirtier, vehicles to enter the zone.

Draft bill starts Britain down the road to pay as you drive Guardian (21/5/06)
Livingstone to charge older, dirtier lorries £200 per day Guardian (8/5/06)

1. What are the external costs and benefits resulting from increased use of the roads?
2. Discuss the extent to which the policy of charging more for older, dirtier vehicles is likely to reduce the external costs of driving.
3. Using diagrams as appropriate, show the likely impact of pay-as-you-drive schemes on the social equilibrium in the transport market.
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