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Why the EV charger in the Nullarbor makes a lot of sense

Doing the viral rounds is a short video by Macca showing the EV charger in the Nullarbor, which runs on diesel.

The posts sharing the video most follow this logic:

“You’re powering an EV by diesel, therefore there’s no point to the EV, may as well have a diesel car”

Then add a few lolz, and commentary on general stupidity of EVs.

That’s incorrect for a few reasons:

Diesel-electric-EV power is more efficient than diesel

So let’s say we have 20L of diesel. We can take that 20L and put it into a diesel car, or we can put that same 20l into a diesel generator, generate electricity, and charge an EV. Could the EV drive further than the diesel car?

Maybe yes.

Sounds odd, but it’s true. A diesel car is energy-inefficient; it only converts around 20% of the energy in its fuel tank to moving the car. The rest is lost is heat (that’s why we have radiators), friction with all those gears, valves and the like, not to mention noise – yes, generating noise costs you fuel. On the other hand, an electric car converts around 85%+ of its energy into motion because there are far fewer moving parts, and much less heat to manage. So for say X units of energy, the EV will go a lot further than the diesel. There’s a zillion links with evidence for this, or just ask any mechanical engineer.

OK, but hang on, we’ve got a diesel generator, so that cancels out, right?

Maybe. A generator is a very efficient diesel. It runs at around 35-40% efficiency (source and source) because it is designed to run at a constant RPM. The designer of a generator engine also need not be concerned with many compromises the car engine designer needs to worry about such as the revving up and down of a car engine, less trade efficiency for noise, vibration and harshness, less concern about engine weight or size, and it doesn’t need to be designed for all the rigours of a moving car. There are energy conversion losses to account for too which need to be factored in which are significant.

So what we end up with is a litre of diesel consumed by the generator may be able to push an EV further down the road than that same litre used in a diesel car. Or it may not. Now you can of course choose examples that skew the results either way; use an old, inefficient generator and a high-consumption electric car vs a very efficient small diesel for example, and the rate of charge is a factor too, the use the cars are put to etc etc etc. But the general point is that charging an EV off diesel isn’t necessarily the environmental disaster it appears to be, but neither it is as good for the environment as some would suggest. If you’re interested in the actual numbers, read this.

The Nullabor generator runs on biodiesel

The original diesel engine first ran in 1893 using peanut oil as a fuel. It was only later we started to use oil-based diesel. Today, many people run their diesels on biodiesel which can be partially or completely made from used cooking oil.

I used to have a mate who’d do the rounds in his Defender 130 collecting barrels of used cooking oil which he got for free, then he’d take them to his shed and do some magic involving various chemicals, and shortly thereafter he’d pour the concoction into his TD5 engine and motor away. Extremely cheap, and environmentally friendly fuelling as not only is it not fossil fuel, disposal of cooking oil is a problem anyway.

So yes, it’s important to note the fuel used for the generator. Not only does biodiesel not require mining or much transportation, the refinement process is simpler, and the exhaust is less polluting. Why haven’t you heard of it before? Excellent question, glad you asked, please go back in time and enquire with the governments of the last many decades. My mate hid his operation as he didn’t feel like paying a lot of excise on it, and when I wrote it up for a magazine I anonymised him.

The generator is a one-off, short-term solution

Crossing the Nullarbor in an EV is difficult as there’s so few chargers. That’s why that one exists. It’s a short-term, one-off solution and in time will be replaced with a conventional charger. The fact that it exists does not invalidate the entire argument for EVs which, over their life, will probably be charged off diesel for what, 0.01% of their total mileage.

The title image is a Hyundai Kona EV I drove from Melbourne to Adelaide and back in 2019. At the time there were no fast chargers, so I used a 3-phase outlet in a showgrounds. Took ages to charge, total trip time around 18 hours. In 2022 I did the same trip again and used fast chargers – a very different result. Read more about that here.

But what about….?

Now while I have defended the use of the biodiesel charger, let’s be clear – there are very real problems with EVs when it comes to 4X4 touring and towing. Simply, no EV on the planet can do the sort of job we need it to do, and won’t until there’s a step-change advance in battery tech, and I’m talking double the energy density at least – so we get twice the range from a battery of a given size and weight. Hopefully solid-state batteries will provide that leap.

There is also the very significant problem of infrastructure in remote areas, particularly at peak times for touring. The pro-EV people need to understand these problems and help address them, not dismiss those that tour as “idiots who tow a block of flats over the Nullarbor” – the current favourite put-down and limit their thinking to the inner city and suburbs, or at best capital-to-capital freeway runs. Similarly, the EV sceptics need to look at the actual facts not rely on semi-informed scaremongering.

More to read:

Now I’ve upset both sides of the argument, if you want to see some actual facts and figures around towing with an EV watch this:

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