Circular’s editor Ian Farrell explores how hydrogen-powered refuse collection vehicles could play an important part in lowering the sector’s carbon footprint – not just in the future, but right now.
The topic of hydrogen comes up often in Circular. In past issues, we’ve discussed its role as a clean, sustainable energy source and written about how the waste sector can help with its production, from sources such as biomass.
But our industry’s involvement with hydrogen isn’t limited to its production, we’re expected to benefit as consumers too.
Hydrogen is a key piece in the net-zero jigsaw because it can decarbonise activities that electrification cannot. Think shipping, air travel and HGVs. In the waste sector, hydrogen is increasingly emerging as a fuel for refuse-gathering vehicles (RGVs), which are notoriously power hungry.
An RGV can be thought of as a very heavy lorry with plant machinery fixed to the top of it. It might be expected to visit 2,000 homes on a 50-mile round trip, bringing 10 tonnes of waste back to a depot. That all requires a great deal more power than your typical Tesla, limiting what can be achieved in a day.
Nevertheless, motivated by emissions targets, electric vehicle (EV) technology has been applied to RGVs – in locations such as Cambridge, for instance, where hills are few and far between and the city itself is relatively compact.
Bringing hydrogen power to local authorities
One of the local authority professionals who brought EVs to Cambridge’s RGV fleet is former CIWM president Trevor Nichol, who currently works for St Helens Council. He’s now considering hydrogen power, motivated by the promise of increased performance and reduced greenhouse gas emissions.
“When I joined St Helens, there was already discussion about replacing our RGV fleet,” he says. “A climate emergency had been declared and an action plan for achieving net zero had been published, so there was a real incentive for change. About 14% of our carbon emissions come from our fleet, and a large chunk of that is RGVs.”
Initially, Nichol considered EVs, but he found the St Helens depot would have needed an extensive electricity upgrade. That’s when he turned to hydrogen power.
“I’d looked at hydrogen back in Cambridge. It actually works very well in the Merseyside areas because there is more of a hydrogen economy already existing here in the first place,” he says.
A climate emergency had been declared and an action plan for achieving net zero had been published, so there was a real incentive for change.
The extensive chemical industry in the north-west, which uses hydrogen as a feedstock, means that production and transportation infrastructure already exists in the area. It’s a massive bonus.
“There is also discussion about tidal energy on the Mersey, which could be used to make clean hydrogen locally,” Nichol adds.
St Helens has recently secured funding for a number of hydrogen-powered buses, whose depot is just across the road from the RGV fleet, and that also helps. It means the two fleets can eventually share fuelling facilities.
St Helens has just taken delivery of its first hydrogen-powered RGV, which is expected to go into service almost immediately. It was designed and produced by FAUN Zoeller – part of the German-owned Kirchhoff group.
“We recognised that refuse trucks use a lot of energy,” says FAUN Zoeller’s CEO, Simon Hyde. “That’s a language we like to use; it’s not just about tailpipe emissions, it’s about energy.
“We are an agnostic company, meaning we can offer you a diesel RGV, an electric RGV and now a hybrid hydrogen-electric RGV too,” he says.
The benefits of hydrogen
FAUN Zoeller’s approach has been to use hydrogen fuel cells as a “battery charger”, keeping the RGV’s 85 kW Li-ion battery topped up as it powers its electric propulsion and waste compacting facilities. The vehicle can be configured with between 1-4 hydrogen fuel tanks and 1-3 fuel cells, depending on the range required and how much extra “oomph” is needed.
“The ultimate is four tanks and three fuel cells, which gives you a 500km range,” Hyde says, adding that helping a local authority to decide on its needs is all part of the service.
“We can study a local authority’s existing RGV rounds and measure the energy being expended with our data loggers. We give each a flag – green, amber or red – that indicates whether a 300kW battery-powered EV would be suitable or if a hydrogen vehicle would be better,” he says.
While recharging an RGV can take hours, topping up with hydrogen is much faster – less than 10 minutes.
But range is not the only factor driving an interest in hydrogen; it can also work out cheaper overall.
“In London, I’ve talked with local authorities that want to replace 24 diesel RGVs with a low-carbon alternative. They calculate they’ll need 48 EVs to do the same thing, but I’m able to say ‘with hydrogen you could do it with 18’,” Hyde says.
He adds: “While recharging an RGV can take hours, topping up with hydrogen is much faster – less than 10 minutes. That lets you double shift with the same vehicle.
“Whether you buy EV or hydrogen, the cost is going to be high anyway, so why not rethink how you do things? In the morning you go out and collect 10 tonnes of waste.
“Then you go back to the depot, unload and top up with hydrogen, then get out and collect another 10 tonnes on the second round. You could even do one in the afternoon, and one in the evening with other crews,” Hyde says.
The future of the hydrogen collection vehicles
In St Helens, Nichol describes his fleet’s newest addition as having “all the bells and whistles” – in other words, four hydrogen tanks and three fuel cells.
“In some regards it is over-specified, but we wanted to evaluate what the vehicle can do, then move down from that, removing tanks and cells to reduce the price of subsequent RGV purchases.
“We need to replace two more RGVs in the near future and we want to wait until we can see how this hydrogen one is performing. That said, we have committed to moving to a hydrogen fleet within the next 10 years, but this has to be up and running alongside other front-line services,” he says.
The future of hydrogen-powered RGVs may well lie in the fuel-cell approach, but hydrogen can also help reduce the carbon footprint of diesel-fuelled vehicles that still have years of life in them.
We have committed to moving to a hydrogen fleet within the next 10 years, but this has to be up and running alongside other front-line services.
“We are also looking at retro-fitting recently purchased diesel vehicles to turn them into hydrogen-diesel hybrids,” says Nicholl, who is partnering with engineering company ULEMCo to modify some of St Helens’ existing vehicles.
ULEMCo’s solution involves mixing diesel with hydrogen from on-board tanks. The mixture is then fed into a conventional diesel engine with a resulting drop in tailpipe emissions of up to 40%.
“We don’t change the base engine, so both performance and operational reliability of a converted vehicle is assured,’ says Nicola Jones, ULEMCo’s business development manager.
“It will continue to run on diesel if no hydrogen is available, and the engine calibration is set so that, when using dual fuel, the driver doesn’t notice any difference. This bridging technology is a practical route that can begin the decarbonisation of fleets using hydrogen today.”
While hydrogen has long been touted as a fuel of the future, it’s clear that its time has now come – powering the vehicles that deliver essential public services and lowering the carbon footprint of the waste and resources sector too.
