Food Scraps Fuel These UK Supermarket Trucks

Eco-friendly retailer Waitrose has introduced a fleet of delivery vehicles that run entirely on biomethane gas.

Gentle irony alert! A major U.K. supermarket chain has deployed a new fleet of trucks powered entirely by fuel made from food scraps. It has a certain cyclical elegance, don't you think?

The British chain Waitrose - similar in scale and vibe to the U.S. chain Whole Foods - has partnered with CNG Fuels, a European provider of renewable biomethane gas. CNG stands for compressed natural gas, although in this case the natural gas is biomethane that's derived entirely from food waste.

On average, biomethane is 35 to 40 percent cheaper than traditional diesel fuel and emits 70 percent less carbon dioxide, according to numbers from CNG Fuels. It's a fundamentally different system than biodiesel or liquefied natural gas, and potentially much more cost effective.

So why isn't everyone fueling up with compressed biomethane? Well, trucks with the modified engines are more expensive, for one thing. Also, there is the matter of infrastructure - biomethane gas stations can be tricky to find.

But as the new Waitrose deal suggests, the math is starting to change - especially in regard to heavy goods vehicles (HGV). With biomethane costs coming down, the extra cost of the trucks is increasingly offset by improved fuel mileage. Biomethane HGVs also run quieter than standard fossil-fuel trucks. And of course, for a company like Waitrose, the PR benefit of running green energy trucks is a kind of currency in itself.

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But the major reason that the new delivery system is commercially viable has to do with range. Previously, dedicated biomethane trucks only had a range of around 300 miles. In cooperation with other U.K. and U.S. companies, CNG Fuels has developed a new kind of engine that stores biomethane fuel at optimized pressure, effectively increasing the range for each truck to upwards of 500 miles.

That improvement, combined with more refueling stations and better pipeline infrastructure, means that biomethane trucks are now genuinely competitive. In fact, according to a recent report in The Sunday Times, other U.K. retailers and municipal agencies are already placing purchase orders for new trucks.

One final note concerning pleasant irony and food waste: Apparently, the city of Leeds is exploring biomethane for its new fleet of refuse lorries. Translation for Yanks: garbage trucks.

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