Driver behaviour can have a huge impact on the environment - and this also applies to electric vehicles
Internal combustion engines are a massive contributor to carbon dioxide emissions through the burning of fossil fuels. The US government reports that fossil fuels were the source of almost three-quarters (74%) of total US human-caused greenhouse gas emissions in 2019. Reducing traffic emissions is also the frontline in the battle against air pollution.
In the UK, according to the Royal College of Physicians, 40,000 people die each year from air-pollution-related illnesses, largely due to nitrogen dioxide (NO2) and particles below 2.5 micrometres (PM2.5). More than 80% of both NO2 and PM2.5 within cities comes from vehicle exhausts.
The UK is therefore set to end the sale of new petrol and diesel cars by 2030 and a second deadline of 2035 has been set for when all new cars and vans need to be zero emission at the tailpipe. The resulting switch to electric vehicles will help the country to comply with the Paris Climate Agreement.
But an important point is being overlooked. In many companies, fleet is the biggest contributor to their carbon footprint and while every fleet is under pressure to ‘decarbonise’ by going electric, this is not a perfect solution. Sourcing the minerals used for batteries, dismantling batteries that have deteriorated, and building and delivering vehicles to customers worldwide all involve substantial CO2 emissions.
What’s more, an important factor is being overlooked. Improving how fleet vehicles are driven is vital if you want to do more than pay lip service to sustainability. Smoother and safer driving is greener driving.
The value of coaching drivers to stick to the limit
Strictly enforcing the 70mph motorway speed limit in the UK would generate ‘meaningful’ improvements in air quality, according to Richard Cuerden, director of TRL Academy. He has referred to it as the ‘elephant in the room’ when talking about reducing emissions. He said: “If we were brave enough to say ‘70mph means 70mph’ we’d see a massive step change.
This is backed up by European research which says there’s between a 12-20 per cent reduction in fuel use when travelling at 70mph compared with 80mph.”
The twin benefits of smooth driving
Cars have an optimal speed range that results in minimum fuel consumption, but the range differs between vehicle types, design and age. But, as New Zealand Energywise rallies made clear, speed is only one factor. No matter what car you are driving, you can reduce fuel consumption (and therefore emissions) by driving more smoothly.
This includes anticipating corners and avoiding sudden braking, along with taking the foot off the accelerator just before reaching the peak of a hill and cruising over it. The optimum average speed (for both professional and average drivers) was typically around 80km/h (50mph) but the key to saving fuel was driving smoothly. Regardless of the car, it was found that drivers can reduce fuel consumption by 15-20% by improving driving habits alone – reducing emissions and operational costs at the same time.
Why harsh braking is bad for the environment
UK scientists have found that metal particles from the abrasion of brake pads have a similar impact to diesel exhausts in the way they cause inflammation and reduce the ability of immune cells to kill bacteria. Dr Ian Mudway, from the MRC Centre for Environment and Health at King’s College London, said: “The focus on diesel exhaust emissions is completely justified, but we should not forget, or discount, the importance of other components, such as metals from mechanical abrasion, especially from brakes. And, as regulations to reduce exhaust emissions kick in, the contribution from these sources is likely to become more significant.” Dr Mudway’s research builds on work by scientists at the University of Bern in Switzerland which found that the harsher the braking, the more particles are released.
The importance of the UN’s Sustainable Development Goals
In September 2017, UN member nations agreed to work towards 17 ‘Global Goals for Sustainable Development by 2030’. Fleets can contribute to these in several ways. The most obvious is the contribution to ‘Climate action’, but there’s also ‘Good health and wellbeing’, ‘Life on Land’, ‘Responsible consumption and production’ and ‘Sustainable cities and communities’.
It’s worth remembering, particularly for quoted companies, as they are required to produce a strategic report that includes information on annual greenhouse gas (GHG) emissions under the Companies Act 2006 (Strategic and Directors’ Reports) Regulations 2013.
Contribute to sustainability targets
Motoring services group RAC has summed up how making small changes to driving style can have a significant impact on the level of emissions. It reports: “Changing gear earlier, not exploring the upper reaches of the rev range, braking sooner and slowing down will all reduce wear and tear, while maintaining efficiency.” It also highlights the benefits of driver monitoring and feedback.
Brightmile has been shown to reduce fuel consumption by 10% at companies like DHL when drivers reduce their speeding and harsh acceleration.
Such results are common. Brightmile customer Avner Weiss of Hanson Israel can testify to this. He says: “Since I implemented app I have observed a 10% drop in fuel consumption as a result of a reduction in speeding and harsh acceleration. This huge saving has been achieved in just two months. Brightmile will really help us meet our sustainability targets.”
Expert analysis
Brightmile asked Tim Smedley, author of Clearing the Air: the Beginning and the End of Air Pollution, whether smoother driving equals greener driving. He told us that there’s lots of evidence that slower and smoother driving produces less air pollution. “Back in the 1990s, research in Germany found that the greater the speed of vehicles in built-up areas, the higher the incidence of acceleration, deceleration, and braking, all of which increase air pollution.
You can probably picture older cars producing a blast of black smoke out of their exhaust pipes? This happens with newer cars, except the efficiency of modern engines means the smoke particles are too small to see.
“Braking also causes abrasion leading to metal particle pollution, and similarly tyre abrasion – the lower the speed, the lower all of this becomes.”
Does this also apply to electric cars? In short, yes, says Tim:
“When Kings College modelled what an all-electric fleet in London would look like, particle pollution only dropped by half. They may not have exhaust pipes, but resuspended solids, brake and tyre wear are still churned up, especially as they tend to be heavier than traditional cars. Slower and smoother is better for all vehicles.”
