British motorists face permanent 60mph speed limits on up to 250 miles of the freeway (or “motorway,” as they are called in the UK) network under a little-known government scheme for the introduction of “controlled motorways.”
To be rolled out over the next five years, controlled speed limits could be pushed down to 50mph and 40mph at the busiest times of the day, according to UK government documents. The scheme will deploy an enormous array of new technology, including average speed cameras and sensors buried in the road surface, and will usually be introduced alongside “hard shoulder” running, where the hard shoulder is used as a fourth lane on very busy stretches of road.
According to a British Department for Transport report, “The system is designed to minimize the risk of flow breakdown and reduce accidents, thereby producing more reliable journey times.” However, it goes on to say, “Mandatory speed limits are set automatically… 60mph and 50mph speed limits are displayed on the overhead gantries to address congestion. When necessary to protect traffic from queues, 40mph limits can also be set.”
In a surprise move, the country's Highways Agency has also been given its own Digital Enforcement Camera System, which downloads information about speeding cars directly to “a secure police office.”
According to research conducted on Britain's M42 motorway, speed limits between 40mph and 60mph are now regarded as ideal for minimizing CO2 emissions.
“Emissions per mile fall as average speed increases to 40-50mph, where the fuel efficiency of the engine is greatest, and then rises as the average speed increases toward 70mph and fuel efficiency falls,” the report states.Source: Autocar