Natural choice

News stories are free to read. Click here for full access to all the features, articles and archive from only £8.99.

Electric power is by no means the only option for bus operators looking to slash emissions. For First West of England, biogas was the perfect solution. Peter Jackson reports on the unveiling of its first batch of gas buses

When it comes to environmentally-friendly buses, electric power usually takes centre stage. It’s not hard to see why; battery-powered buses are almost totally silent, don’t produce any ‘tailpipe’ emissions and, although they don’t have the range of an equivalent diesel bus, the technology has come so far in recent years that they can now cover a multitude of services with ease.

However, they’re not a ‘one size fits all’ solution by any means. And while they’re clean once they’re out on the road, there are still question marks over battery disposal and manufacture, as well as the sustainability of the electricity used to charge them.

Are you enjoying this feature? Why not subscribe to continue reading?

Subscribe for 4 issues/weeks from only £2.99
Or login if you are already a subscriber

By subscribing you will benefit from:

  • Operator & Supplier Profiles
  • Face-to-Face Interviews
  • Latest News
  • Test Drives and Reviews
  • Legal Updates
  • Route Focus
  • Industry Insider Opinions
  • Passenger Perspective
  • Vehicle Launches
  • and much more!
[/wlm_nonmember] [wlm_ismember]

With all of that in mind, biogas remains an option well worth considering. Nottingham City Transport has led the way here in the UK in adopting the fuel, and currently operates 120 ADL Enviro400CBG City-bodied Scania buses just like First’s new arrivals. Though they may not be zero-emission, the vehicles emit 85% less CO2 than their diesel equivalents – an enormous reduction. For First West of England, biogas made perfect sense. “When people think green, they say electric – at First West of England we’re doing something different,” said Managing Director James Freeman.

Confident in gas
First West of England welcomed stakeholders and media to its Lawrence Hill depot last Monday (10 February) to unveil the first batch of its gas-powered ‘deckers, and show off the newly-installed fuelling infrastructure.

The first 10 of the 77-vehicle order were delivered in early January and began operating on the metrobus m3 service, refuelling temporarily at Bristol Community Transport’s Parson Street facility. Now the Lawrence Hill refuelling station is up and running, they will now return there at the end of the day for a ‘fresh’ tank of recycled food waste.

Joining them this week will be a further 27 buses, which are to operate on a revitalised Citylines service in the east of the city. It was these vehicles – painted in a sophisticated shade of red and sporting a new livery – which were on display at the launch event. The 69-platers are replacing all of the current diesel vehicles running on routes 42 to 45, demonstrating First’s confidence in them and the gas infrastructure.

Speaking of infrastructure, the Lawrence Hill gas filling station was designed and installed by Gas Bus Alliance (which also supplies the gas itself) at a cost of over £2m. Built over a period of nine months, the facility can provide 100% compressed biomethane for up to 100 buses, giving First plenty of headroom to expand its gas fleet in future. Better still, the station can be expanded further if required to cater for yet more buses – the depot has plenty of room to spare. The environmental benefits of the buses are further enhanced as the gas is taken directly from the mains, eliminating the need for tanks of gas to be delivered by diesel-powered lorries.

The Parson Street, Bedminster facility – which was only opened last summer – will continue to operate alongside the new Lawrence Hill station. By April, First says that 99 biogas buses will be in operation in Bristol.

In total, the scheme has cost £28m to deliver over a three-year period, £4.79m of which came from a government grant through the Low Emission Bus Scheme (LEBS).

Waste not want not

Tony Griffiths, Sales Director at Gas Bus Alliance

Tony Griffiths, Sales Director at Gas Bus Alliance, gave a presentation on how biomethane refuelling infrastructure works, and why electric isn’t always the ‘perfect’ solution for emissions reduction. “Biomethane is the cleanest burning fuel that’s available at the moment; until hydrogen eventually gets there, this is the best option. Our gas stations in the UK have effectively removed 30 million kg of CO2 from the atmosphere since we started,” he began.

“Biomethane can be classed as a carbon neutral fuel because all of it is produced from waste food here in the UK. We want all councils to embrace waste food collection; otherwise, it’s not only a terrible waste but all of the methane produced by the waste goes into the atmosphere and creates even more carbon dioxide. We can also collect methane from manure and human waste; the ‘poo bus’ which ran here in Bristol previously was an example of that.

“By the time our biomethane is injected into the grid, it’s exactly the same specification as natural gas – but natural gas is a fossil fuel. Because biomethane is produced from waste, it’s a carbon neutral fuel – that’s the differentiation.

“When the gas is in the grid it’s pressurised to about 2 bar; when it reaches the filling station, it’s then compressed to about 300 bar, stored, then put into a dispenser and finally into the bus.

“Refuelling is ultra-safe. When the dispenser is connected to the bus, it squirts some gas in to check the pressure; if it is less than 250 bar (indicating a leak), it won’t then allow you to put any more gas in. Refuelling takes approximately 4-5 minutes from empty to full.

“When we compare carbon neutral biomethane to electric, we’re then looking at lithium and cobalt mining, quarries, shipping to China for battery manufacture… then in terms of the power to charge them, it could be gas, wind, nuclear or coal. We still use coal, and we have to bring power in from Europe to supplement the power that we need in the UK. That power does come from coal power stations.

“We also need to understand battery disposal. Only 5% of batteries in Europe are recycled at the end of their lives; the rest are either going into landfill or elsewhere. The reason for this is that it’s cheaper to buy the materials used in batteries (mainly lithium and cobalt) as virgin materials than to recycle it.

“So there’s a huge question mark over recycling batteries, and an electric bus will need at least two batteries in its lifetime. People tend to ignore some of these things.”

James Freeman explained that the process of installing the facilities at Lawrence Hill involved an unforeseen risk of explosion! “One of the worries we had was that, because the Second World War did so much damage to the buildings here, there was a risk that when we started opening up the yard we would come across an unexploded ordnance. So we had to have an expert standing beside the shovel at all times to say, ‘that’s a bomb, stop.’ Fortunately he never said anything!”

A win-win for Bristol

The interior of the new vehicles was impressive

James is understandably proud of the new fleet. “This second and larger-capacity facility is a crucial next stage in our bio-methane journey: it means we can roll out cleaner, greener vehicles and contribute substantially to help clean up the local air,” he said.

“As we are now able to fuel more bio-methane powered gas vehicles than we currently have in our fleets, we are looking to open the facility up to other, third party commercial operations in the future. Indeed, we are already in negotiation with one organisation already. We’re really putting the West of England at the forefront of clean commercial fleets.

“Meanwhile, I am also delighted that we have been able to deploy this next batch of buses – 40 in all on routes in the East of the city and into South Gloucestershire, bringing the very latest equipment to many thousands of our customers each week from next week.”

West of England Mayor Tim Bowles added: “It’s fantastic to see even more biogas buses getting out and about and the infrastructure to support them. These brand new, low-emission buses not only make customers’ journeys better, but also dramatically improve air quality and cut carbon emissions compared to diesel buses. They support my ambition to improve public transport and give people more sustainable ways to travel to keep our region moving.

“We’re already seeing more than 100,000 passenger journeys being made by metrobus every week, with the latest passenger survey showing that it has taken 19,000 car journeys off the road. I want to build on that success with more services and better connections as part of my wider objective of getting more people to switch to using public transport across the West of England.”

Bristol Mayor Marvin Rees said: “We welcome this significant investment in new, cleaner buses and infrastructure as part of our drive to reduce air pollution and achieve carbon neutrality.

“As we plan how we transform Bristol’s transport, through modernising the network, launching the bus deal and mass transit, we want to encourage partners to take these important steps to make Bristol better for everyone. “

Kerry McCarthy MP for East Bristol concluded: “This announcement is a win-win for communities in the east of Bristol, and the city as a whole. With these new buses running on local routes, we can help improve air quality – and quality of travel for local residents. It shows that taking steps to protect the environment needn’t come at a cost to passengers, with the new state-of-the-art bus fleet a real improvement on the diesel buses currently in service. I was pleased to get a preview when I visited the depot recently with Keir Starmer, and to speak to some of the drivers.

“Investment in the new biogas station is also a positive step forward, putting East Bristol at the forefront of efforts to make Bristol a cleaner, greener city. There is still a long way to go, but investments like this will make a real difference.”

The vehicles
Underpinning the Enviro400CBG City is Scania’s Euro VI gas chassis. The OC09 101 9.3-litre, five-cylinder engine mounted in the rear produces 280hp at 1,900rpm and 1,350 Nm of torque between 1,000 and 1,400 rpm – comparable figures to the diesel-powered DC09. Two 515-litre fuel tanks provide enough gas for a 250-mile range.

Besides being significantly cleaner than the vehicles that they replace, the new buses feature comfortable high-back seats (with USB ports fitted) and a second wheelchair space – a first for the operator. The wood-effect floor is also completely flat, making it easier to clean. As is to be expected from Scania and ADL, build quality was impressive. On our short ride around the depot – which included traversing a few speedbumps – the bus we travelled on was pleasingly rattle-free, comfortable and smooth.