It isn't a new concept but now it is official -- speed bumps are bad for the environment.
According to an AA-sponsored study, the traffic 'calming' measure doubles the amount of CO2 emissions from cars because they force drivers to brake and accelerate, often many times on a short stretch of road.
Constant speeds are better for reducing emissions.
A car that achieves 58.15 mpg travelling at a steady 30mph (48 km/h) will deliver only 30.85 mpg when going over humps, according to tests carried out on a small and a medium-sized car at the Millbrook Proving Ground in England.
The study also showed that reducing the speed limit to 20mph (32 km/h) resulted in 10 percent higher emissions. This is because car engines are designed to be most efficient at speeds above 30mph (48 km/h). BB
