Doesn’t it use more fuel to drive at 20mph?

NO!

This is a common myth. However unsurprisingly the main factor that affects your fuel consumption in built-up areas the most isn’t the number on the speed limit sign, it is your driving style and the amount of stopping and starting during your journey.

The Department for Transport recently issued revised guidance about 20mph limits which states “driving more slowly at a steady pace will save fuel and carbon dioxide emissions, unless an unnecessarily low gear is used”.

Even if you look at steady-state speed tests (which do not accurately reflect real world driving conditions) What Car found that ‘the slower you go with the vehicle running smoothly, the less fuel you will use.’

What they all forgot to mention is that making the roads safer will encourage more people to leave their car at home when they don’t need it and walk or cycle instead, meaning a 100% reduction in fuel consumption!!!