Many drivers believe that switching on the cruise control will save them fuel during a journey. And generally that tends to be the case, but not always, according to motoring experts. They say drivers shouldn't always assume cruise control is the most efficient option.
When Cruise Control Helps
Cruise control is most beneficial on flat, open stretches of road like motorways. This is usually the most cost-effective way to use the feature. It also tends to be most beneficial in terms of savings over longer journeys.
A motoring expert at Interfuels explained: "Cruise control does exactly what it promises on flat, open stretches of road. It holds a consistent speed and stops the small unconscious variations in acceleration that most drivers do not even notice. On those conditions, it can make a measurable difference to how much fuel you use over a long journey."
The Problem with Hills
However, this isn't the case on hills. The expert added: "On hills, it's a different story. When coming down a hill, a driver naturally eases off the accelerator, using the momentum built up on the descent to carry them forward without burning extra fuel. Cruise control doesn't take these gradient changes into consideration, often braking when going downhill to stick to the same speed. This just ends up wasting the momentum that a driver would use, and makes the engine work harder on the climb back up."
Expert Advice
The spokesperson continued: "The studies that show cruise control saving fuel are mostly conducted on flat roads in ideal conditions. The moment you introduce hills, which is almost everywhere in the UK outside of certain motorway stretches, an experienced driver who reads the road ahead will generally do better than the system. The car cannot see what is coming. The driver can."
Therefore, drivers should consider turning off cruise control when driving on hilly terrain to maximize fuel efficiency.
