The Government says previous concerns over the impact an increase would have on pollution could need revisiting with a rise in electric vehicles (EVs).
The transport secretary Shapps told the Daily Telegraph that “there is an argument” for raising the speed limit on motorways and dual carriageways at the same time as lowering them to 20mph around schools.
He said that concerns over the extra pollution that would accompany increased speeds had previously halted discussions on the matter. However, with the rising number of vehicles with zero tailpipe emissions he argued that the matter should be revisited.
Speaking at a transport debate during the Conservative Party Conference in Manchester, he said: "On 80mph speed limits, I've been thinking about this issue and maybe even sought advice on the subject of late. I think there is an argument for looking at our speed limits, both in terms of higher speed limits and actually lower limits - 20mph outside of schools.
“When it was last looked at in 2011, it was thought the carbon emission addition would be too great. But since I am a driver of an electric car myself I got to thinking about whether that would still be the case. I think there is an argument that once you have increased the level of electrification and therefore decreased or entirely removed carbon, that you might look at those things again."
However, the plan was later abandoned after the independent committee on climate change warned that it would generate an extra 2.2 million tonnes of CO2 each year.
RAC head of policy Nicholas Lyes said the transport secretary raises a “valid point” in relation to the possibility that overall emissions could be lower if a move to an 80mph limit was accompanied by a large increase in EVs.
But, he added: "Any move to raise speed limits on motorways to 80mph is fundamentally an issue of safety. Part of the problem is that at present, there is a high proportion of drivers that break the 70mph limit, and drive nearer to 80mph. If the speed limit were to be changed to 80mph, there is a risk that the new default becomes even higher.”
With motorways currently the safest roads on the entire network, Lyes said he wouldn’t want to see anything happen that changes this.
“Unless there is compelling evidence that a change in the limit on some stretches of road would not adversely affect safety, the current limit should be retained,” he said.