Net Zero is a journey

11th Nov 2019


This week Bristol City Council voted to ban diesel cars from driving in some parts of their city. Not just old, dirty diesels but all diesel cars (even those with Euro6 engines). Now to still allow diesel taxis, vans and HGVs to drive on the same roads may be a little daft – but this decision is a signal that firstly diesel engines, regardless of their actual environmental impact, are seen as the problem. So what do the good drivers of Bristol do?

Turn to petrol, with the higher carbon emissions? Not a great direction of travel. Turn to EVs? The same week saw the Department of Transport publish their EV charging point league table. Bristol has a total of, wait for it, 14 public fast charging points. That’s a total of 672 cars that can be fast-charged over a 24 hour period. It doesn’t even scratch the surface. Nor does it tackle the biggest polluter, the one that disproportionately emits carbon and NOx, diesel HGVs.

Comprising just 2 per cent of vehicles on our roads, they cover 6 per cent of the miles travelled across the UK but produce17 per cent of transport carbon emissions and release 48 per cent of roadside nitrogen oxides. So to make the biggest impact, tackling HGVs first would have been the best step on the journey to both clean air and NetZero. 

But HGVs can’t be battery-powered. That’s correct, the weight of batteries required to actually power the vehicle would be so great as to reduce the actual payload carried. Totally uneconomic. So let’s turn to a viable alternative.  

Natural gas HGVs offer well-to-wheel carbon savings of around 20 per cent, according to Element Energy, over diesel. That’s ok, part of the journey, but not good enough on its own to meet Net Zero. If that gas vehicle used biomethane, then the carbon savings rocket to around 85 per cent. Now we’re cooking. Going further, well that looks like hydrogen, emitting zero carbon. 

Fleet managers wanting to get their goods into towns and cities need to act fast. If they don’t switch from diesel to cleaner gas, they will simply go out of business. Whether this is fair to diesel or not, really has become immaterial. In the battle for public opinion, diesel is bad so the most viable alternative, a cleaner gas, must be good.

Best wishes

Mike Foster, CEO