David Cameron orders his new policy unit to examine options to introduce more transparency to fuel pricing

Motorway service stations may be forced to advertise the price of petrol sold by rival companies on roadside hoardings as the government moves to bring down the cost of fuel by introducing a French-style system of transparency.

David Cameron has ordered his new Downing Street policy unit to examine options to allow Britain to follow the example of French autoroutes, where service stations have to advertise the price of petrol at subsequent stations.

The prime minister, who has asked the head of the new No 10 policy unit, Jo Johnson, to prioritise cost-of-living issues, has asked him to examine a recent OFT report on motorway fuel prices. The report, highlighted by George Osborne in his budget this year, said that petrol bought on motorways is on average 7.5p a litre more expensive than fuel bought elsewhere. Motorway diesel is 8p more expensive.

The policy unit is examining three options in which motorway service stations would:

• Advertise the price of their petrol on their motorway signposts. At the moment motorists only learn the cost of petrol once they have pulled off the motorway and see the prices displayed by the forecourt.

• Add the price of petrol for subsequent service stations to existing Highways Agency signposts.

• Follow the French example and require motorway service stations to advertise the price of petrol for subsequent outlets even if they are run by different companies.

A No 10 source said: "The prime minister has asked the policy unit to prioritise cost-of-living issues. This is one area where we believe transparency can drive down prices and give motorists a better deal.

"The problem on the motorway is that fuel prices are only ever advertised on the forecourt. That is the legal requirement. But by the time you have pulled off the motorway and stopped it is often more trouble than it is worth to go onto the next service station in particular as you have no idea whether it will be any cheaper."

The prime minister's decision to ask his policy unit to focus on cost-of-living issues shows Cameron has heeded the advice of his pollsters and his general election campaign director, Lynton Crosby. They have said that Downing Street must provide tangible proof that it is focusing on the rising cost of living, which has been blamed for voters' disaffection with the main parties.

The OFT report said higher fuel prices may be caused by the higher costs of running motorway forecourts. But it added: "Motorway prices may also be higher because consumers are less likely to shop around. Drivers who buy fuel on the motorway may have little choice but to pay a higher price if they are running low on fuel and most drivers are unlikely to want to leave the motorway to search for cheaper fuel. The fact that drivers are not able to view prices until they have pulled into the service station makes it particularly difficult for drivers to decide where to buy."

Germany are once again debating a speed limit for the autobahn system but does it really help? And what is happening to motorway deaths across Europe?
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Once again the debate on whether German autobahns ought to have a speed limit has resurfaced. German Chancellor Angela Merkel's challenger, Peer Steinbrueck has been trying to halt a debate set off by a Social Democrat colleague about whether to introduce speed limits on all German highways.

The chairman of his party was quoted last Wednesday as saying that a 75 mph (120 kph) autobahn limit would make sense because statistics suggest it would reduce serious accidents, according to Associated Press (AP).

Stretches of the motorway, most famously referenced by Top Gear, currently have no speed limit although the advisory limit stands at 81mph. The autobahn system, with a total length of 12,845km, has often been the topic of debate in the past and is a guaranteed catalyst for road safety groups, environmentalists and politicians.

But do speed limits affect the number of deaths on motorways? A 2008 report by the European Transport Safety Council (ETSC) found that of the 645 road deaths in Germany in 2006, 67% occurred on on motorway sections without limits and 33% on stretches with a permanent limit. The fact that 33% of German motorways have a permanent limit and 67% have either a temporary limit or none means that these figures, at first glance, show that having a speed limit does not the lower the number of fatalities on motorways. But as ETSC note: 'this similarity of percentages takes no account of traffic volumes on different sections.'

The report stresses though that:

"the relationship between speed and road accidents has been studied extensively and is very clear: the higher the speed, the greater the probability of a crash and the severity of the crashes."

The relationship between speed and the increase in the number of deaths and injuries has lead to some interesting academic research. Writing about the 'power model' devised by Rune Elvik, from Norway's Institute of Transport Economics, Peter Walker explains what insights it can offer:

Using the most widely accepted statistical model, drawn up by a Norwegian academic using data from 100 studies in more than a dozen countries, an increase in average traffic speeds of just 3mph – a typical change for a 10mph rise – would be expected to cause more than 25 extra deaths a year on motorways and more than 100 serious injuries.

But of course, countries differ. Not only in their standard of driving but in the total lengths of motorway, average flows of vehicles, geographical situation (i.e many use Germany's autobahns to cross over into other countries) and their overall transport infrastructure.

For many countries rural road fatalities account for the highest proportion of road deaths. Rural roads killed five times more people than motorways in Germany between 2007-9, accounting for 60% for road deaths, versus 12% for motorways.

A 1991 case study used in the ETSC report illustrates the results of introducing a speed limit. A 130km speed limit was introduced on a 167km section of the A61 in Rheinland-Pfalz combined with a ban on overtaking heavy good vehicles. The result of both these measures was a 30% reduction in fatal and severe injury accidents.

Professor Benjamin Heydecker, the Head of the Centre for Transport Studies at University College London also found that 'during the 45 years since the current motorway speed limit of 70mph was first implemented, the risk of road accident fatality per vehicle-km of travel has fallen to less than 1/13 of what it was'. But as Heydecker explains in his piece for the London School of Economics (LSE), roads have become safer over that period of time due to a variety of factors including road and vehicle development and not just the introduction of the speed limit.

In their 2008 report, the ETSC were firm and clear in their overall conclusion:

empirical evidence indicates that all instances' of introduced speed limits on German motorways have caused very large casualty reductions.

Do you think a speed limit should be introduced on Germany's autobahns? What other factors could we look at? and is there another way to reduce motorway deaths? Comment in the thread below.

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Insurer cancelled my policy but is still chasing me for outstanding premium

My car insurance was with One Call Direct until October 2012. When my car failed its MOT, I purchased another vehicle. I telephoned One Call and it gave me a fair quote and I was happy to proceed. However, when I mentioned the car was dual fuel, One Call said that it would have to investigate.

I was then told it would not be able to insure my vehicle. In effect, it cancelled the policy. Since then the company has been chasing me for the outstanding premium, in excess of £200. It is refusing to confirm my no-claims discount with my new insurer until this is paid. Understandably, my new insurer is now threatening to cancel my insurance. TW, Bournemouth

One Call Direct said they could not issue us with a statement on the grounds that this would breach data protection laws (despite having your permission to do so). The good news is it was very quick to resolve this. It called you within minutes of our call and said you owed nothing, and that it would issue the no-claims certificate to your new insurer pronto.

A spokesperson apologised and said the company would ensure its staff were trained properly to prevent this type of error in the future.

We welcome letters but cannot answer individually. Email us at This e-mail address is being protected from spambots. You need JavaScript enabled to view it or write to Bachelor & Brignall, Money, the Guardian, 90 York Way, London N1 9GU. Please include a daytime phone number

Hyundai claims the black box installed as part of a young driver policy has invalidated my five-year warranty

I took delivery of a brand new Hyundai in March this year. We then took out a young driver insurance policy with the Co-op. The black box that came with it was fitted behind the dashboard. After installation, there was a rattle. I took the car to my local Hyundai garage and was told it was a faulty instrument cluster and that I needed a new panel at a cost of £533.86. Hyundai refused to cover me under its warranty as it claimed the tracker box installer invalidated it.

I've spoken to the Co-op and they sent out an installer to check the work and say it was done correctly. Neither side will budge but I don't want to pay for damage I didn't cause. EE, Slough, Berks

Hyundai and the Co-op have continued to fight among themselves over who is responsible for this – but either way you should not have to foot the bill. Normally, the installation of any device in a car after manufacture (an "after-market device") such as a stereo or, as in this case, a black box, does not invalidate the car manufacturer's warranty.

However, Hyundai claims that the security tags on the back of the instrument cluster had been broken during installation and that the security tag clearly states "warranty void if removed".

If the Co-op had been at fault it should cover the costs. However, it sent out two separate engineers to check the work and both stated that the rattle in your car was not caused by the box. It maintains this position but has agreed, as a gesture of goodwill, to arrange and pay for the repairs to be carried out for you so you are not stuck with the bill. In a final blow from Hyundai, when you booked in for the repairs, it told you your warranty would now only be valid for two years. We queried this and it says the information it gave you was wrong – you now have the repair paid for and your full five-year warranty intact.

We welcome letters but cannot answer individually. Email us at This e-mail address is being protected from spambots. You need JavaScript enabled to view it or write to Bachelor & Brignall, Money, the Guardian, 90 York Way, London N1 9GU. Please include a daytime phone number