With recent announcements from state governments such as Victoria regarding a transition towards electric bus fleets, many companies are now operating with a mix of hydrogen and electric buses. ABC delves into how the two differ.
The bus industry is leading the way in many respects, as the world shifts to greener modes of transportation.
It should not come as a surprise to those who work in the industry – buses often operate in city centres, around pedestrians and alfresco dining spaces, so quickly transitioning fleets to zero emissions will help governments clean up cities.
A number of governments are electing to go electric but many fleets are also utilising hydrogen, so which is better?
ENERGY STORAGE
A hydrogen engine works in a similar way to an electric bus but the way the energy is stored and harnessed is where the two differ.
Hydrogen is a clear gas that can be harnessed in a number of ways, including using fossil fuels, but when produced utilising renewable energy, it is green energy source.
Once produced it can be transported similarly to petrol and pumped into tanks on the bus to then be converted into electrical energy in a fuel cell.
This is where the two types become similar – the energy is then either utilised to power the bus or stored in a battery for later use.
An electric bus stores energy from an energy source such as renewable energy or a mains power supply in a battery that powers the driveline.
Both types of buses have similar drive trains or an ‘electric engine’ that powers the vehicle.
THE SET UP
The transition for bus operators to a greener fleet requires a drastic change of the infrastructure within depots.
Where a driver traditionally left a depot to fill up at a fuel station, now much of the refuelling will be done on site, either through hydrogen pumps or battery charging.
Volvo National Engineering and Bodybuild manager Mark Fryer explains some of the challenges companies face when making the move to renewable.
“Hydrogen requires a bigger set up cost for infrastructure due the nature of the gas,” Fryer says.
“There are many additional safety standards and requirements that have to be met in order for this solution to be used in-depot. Also, a lot of training for operators, as this solution is so foreign to most.”
The electric solution requires a battery charger to complete the set up. There is also a number of kilowatts required to charge all vehicles that needs to be considered, the question being has the grid got enough power?
“How can we best use solar power to charge the vehicles? Does the depot need storage batteries? These are all questions operators have to ask,” Fryer says.
For operators completing long range trips such as Melbourne to Canberra they have to make a number of considerations when looking to move to a green bus fleet.
A recent announcement from the Queensland, New South Wales and Victorian state governments may provide a solution for this issue.
In March, the three state governments announced a landmark memorandum of understanding that would see a hydrogen refuelling network installed along the eastern seaboard.
Australian Hydrogen Council (AHC) CEO Dr Fiona Simon says the announcement was an exciting moment for the AHC.
“The collaboration between these three states will facilitate the uptake and use of hydrogen as a fuel for heavy transport along the Eastern highways,” she says.
While charging an electric bus can have a lot of downtime, especially on a long journey, the network or hydrogen pumps along the east coast may solve this problem.
The challenge that operators are faced with is range for each vehicle as more time spent charging and not ferrying customers will increase costs.
Mark Fryer explains some of the challenges that each form of renewable energy has for those considering utilising them.
“Hydrogen allows you to carry more useable energy than an electric but, in electric, 25 per cent of energy is wasted while, in hydrogen, 75 per cent of energy is wasted,” he says.
ELECTRIC ATTRACTION
It appears that state governments are turning to electric buses for inner city bus routes with a number of recent announcements demonstrating where governments view the future of buses for inner city routes.
The Victorian government will roll out 41 buses across five different networks in the state to help Victoria reach its target of net zero emissions by 2050 in a landmark trial.
Minister for public transport Ben Carroll spoke of the importance of the electric bus rollout.
“The electric bus trial will be pivotal in our transition to a more environmentally friendly and sustainable transport network.
“Creating a greener fleet is part of our Bus Plan to develop a more modern and reliable network that will attract more people to the convenience of buses,” Carroll says.
The Queensland government recently opened the first all-electric bus depot on the Gold Coast with 100 per cent of the energy used to charge the buses coming from renewable sources.
The use of solar panels at depots appears to be an effective way to make the fleets as green as possible.
Electric bus fleets are pivotal for governments who aim to reach targets of either zero or net zero emissions.
Transport and Main Roads Minister for Queensland’s state government Mark Bailey says it builds on the state government’s recently released Zero Emissions Vehicle strategy.
“We’ve made a commitment that every new bus in southeast Queensland would be zero emission from 2025, so to see it happening now is a fantastic achievement,” Bailey says.
Mark Fryer explains that, for operators, it is not a simple either/or decision but something where they must establish the needs of the business.
“I think each operator will have to make the choice based on their local factors, including available power to charge batteries, cost of infrastructure and route requirements including range,” he says.
For Volvo, when helping a customer decide what option suits them best, they take a hands-on approach.
“It’s always ultimately the customer’s choice but we can do full simulations on the route to ensure if the electric product is suitable for that route,” Fryer says.
‘We also have the ability to increase or decrease the number of batteries for the customer to ensure their route demands can be met.”
While the move to renewable energy on routes is an exciting moment for the industry, it presents a number of challenges and the coming years will important for the survival of these energy sources.