When it comes to fuel, there’s no right answer

The electric transportation revolution is upon us. Out of the 110,000 cars sold in Australia in September 2023, 10.6 per cent came with a plug, and around eight per cent were pure battery electric, the remainder being plug-in hybrids.

While increasing numbers of Australians are buying EVs for personal transportation, electric power isn’t always the right answer for everyone and their individual needs. Considerations such as range anxiety and the availability of fast chargers across this broad country come into play for personal use. People prone to making regular, long freeway journeys may find a low-consumption combustion engine fits their needs better. And for heavy vehicles, electricity or fuel cell hydrogen isn’t yet a viable alternative to diesel.

Let’s dive in and look at some of these factors and consider that fuels for purpose will drive the mix of vehicles on Australian roads for a long time to come.

Case study: The Tesla Semi

Tesla, the leading producer of consumer-focused EVs, unveiled its battery-powered Tesla Semi in 2017, and despite several high-profile early adopters, including PepsiCo, the vehicle remains in development as full production hasn’t yet been underway.

While the Tesla Semi has all the usual advantages of an EV, including zero emissions (depending on the power source used for charging), along with motors that generate maximum torque from zero RPM, it has several major limitations that apply to rivals in the EV truck market. These include limited range and a lack of dedicated truck charging infrastructure.

Image Source: Tesla.com

With how large Australia is and how long a heavy-vehicle can travel on the long haul, the Tesla Semi’s estimated 800km falls short of the thousand-plus kilometres operators expect to get from their diesel-powered fleet. It has a 900-kWh battery – the longest-range EV cars have between 80-100 kWh – so charging it to full capacity will be time-consuming, presuming the charging infrastructure exists for trucks, which it doesn’t. Operators will be forced to charge their electric trucks at their bases, but again, this means having megawatt chargers installed with the right power sources available at all times.

Overall, the Tesla Semi – and trucks from rivals including Daimler Benz, Volvo, BYD and others – won’t be able to replace long-haul heavy vehicle fleets for a long time, if ever. Their uses will be restricted to relatively short-distance routes, with charging facilities needing to be available at both ends of their journey.

​Where electricity in transportation has a role to play

While it will be a long time before electricity replaces diesel in long haul fleets, it does have a role to play in short-distance trucking and light commercial vehicles – think inner city and suburban deliveries, mail, and couriers.

For these roles, range and charging times are less of an issue. Vehicles can be charged overnight at the base, negating the need to use public charging infrastructure when they're not being used. It’s also important to consider many cities are introducing, or have already introduced, either zero or ultra-low emissions zones in their centres.

In Europe, Amsterdam, Barcelona, Berlin and London are all in the process of rolling out zero emissions zones (ZEZs), while in the US, Los Angeles introduced such a zone for the Port of Los Angeles and surrounding industrial areas in 2020. New York will do the same for lower Manhattan in 2024.

In Asia, Beijing implemented a ZEZ for the city centre in 2019, and a similar program is in place for Shenzhen. In Japan, a ZEZ zone is being introduced for some parts of Tokyo this year.

Several Australian cities have already expressed their interest in implementing zero-emissions zones, and some have already taken steps to do so.

• Melbourne: The City of Melbourne aims to achieve a net zero emissions target by 2040.  The city is considering implementing a ZEZ in the central business district (CBD) as part of this goal.
• Sydney: The New South Wales government has announced plans to introduce ZEZs in Sydney as part of its Net Zero Plan. The government is currently consulting with stakeholders on the design and implementation of the ZEZs.
• Brisbane: The City of Brisbane aims to become a carbon-neutral city by 2030 and is considering implementing a ZEZ in the CBD as part of this goal.
• Adelaide: The South Australian government has announced plans to introduce ZEZs in Adelaide as part of its Climate Action Plan. The government is currently working on a feasibility study for the ZEZs.
• Perth: The City of Perth aims to become by 2050. The city is considering implementing a ZEZ in the CBD as part of this goal.

Infographic: Electric Vehicle Adoption Around The World

Hydrogen: the elephant in the room

With electricity ruling the short distance for heavy vehicles tasks, where does this leave hydrogen? Hydrogen has been mooted as the perfect power source for trucks; it’s the most abundant element in the universe, and when it’s converted to power, either through a fuel cell or combustion, the only by-product is water. So, it’s clean and, in theory, readily available.

Again, hydrogen falls when it comes to fuelling infrastructure and producing the raw material. While the Australian government has a hydrogen plan and aims to make the nation into a ‘hydrogen superpower,’ the element isn’t found in isolation. This means industrial processes are needed to separate it from the compounds it’s found in, and those processes tend to be energy intensive. 

Hydrogen has an energy density of approximately 120 MJ/kg, which is almost three times more than diesel or gasoline. In electrical terms, the energy density of hydrogen is equal to 33.6 kWh of usable energy per kg, versus diesel which only holds about 12–14 kWh per kg. This means that 1 kg of hydrogen, used in a fuel cell to power an electric motor, contains approximately the same energy as a gallon of diesel.

Environmentally friendly fuels are only as clean as the ways they’re produced, and right now, it’s not possible to make hydrogen using sustainable methods at the scale needed to replace diesel. And then there’s the problem of fuelling infrastructure, which is essentially non-existent in Australia.

Once these significant hurdles are overcome in supply, demand for these vehicles would dominate the short to medium distance space, where light trucks or a simple semi can be used over their ICE-based cousins. You would have fewer complaints from the community around emissions and get what you need to get done on time. Hydrogen is a great fuel for its purpose, and it is a great choice where it is applicable.

The upshot is diesel will be a component of the fuels mix for Australian vehicles well into the future. While electricity has promise for cars and light commercial trucks, there’s no technology on the horizon to replace diesel for long-haul fleets.