Today, the largest truck in the world is the Liebherr T282B. This 203 tonne beast is 14.5 meters long and 7.4 meters high. It can haul a massive 365 tonnes of material and is propelled by one of the most powerful internal combustion engines in the world, a 90 litre diesel engine weighing 10.5 tonnes. However, unlike a normal combustion engine which mechanically propels the vehicle, the 90 litre engine create 2.6 MW of electrical power which is in turn is used to move the truck using an electric drive. This enables less wear and tear on mechanical parts, such as gearboxes. This not only reduces downtime for maintenance, it also makes the whole drive train much lighter than a mechanical one giving the T282B a greater payload capacity than would otherwise be possible. Similarly, most trains are either directly powered by electricity from overhead lines or more increasingly from large onboard diesel powered engines which also use electric drives. They are the most effective and efficient way to deliver power to the wheels, because the electric drive is more flexible and easier to control than a combustion engine, which also makes accelerating and braking much easier. It also makes the driving experience much more fun which is why the Tesla S is the best selling luxury car in the US. This is also a large part of the reason why electricity will power the automobile of the future.
Unfortunately, using a small combustion engine to generate electricity to drive the wheels of an automobile makes no sense. The efficiency losses and thus the costs are just high. When it comes to burning coal, gas or oil bigger is indeed better. The bigger the plant, the more efficient it runs. The largest diesel engine in the world is the Finnish 80 MW Wartsila-Sulzer RTA 96-C, a turbo charged two-stroke diesel engine that is used to power huge container ships. It is 52% efficient, meaning that the other 48% is lost and not used to power the car. But this is still better than an automobile engine which has efficiencies of circa 30%. An electric motor in contrast can be over 90% efficient.
So why not just go electric without the use of a combustion engine? One way to do that is with fuel cells but we are still at early stages in their commercialization noting that there are only three commercially available fuel cells are on our roads today in the form of Toyota’s Mirai, Hyundai ’s ix35, and the Honda Clarity. And let’s be clear they bring nowhere near the performance that a modern battery powered EV brings. The Honda Clarity takes over 11 seconds to accelerate from 0-100km/h as compared to the BMW i3 with 7 seconds and the Tesla S with 3 seconds!
The big drawback of the battery powered EV is the range but that is improving. The original BMW i3 (launched two years ago) had a range of 190km while the latest release has a range of 300km. And we already have the Tesla Model S which can do up to 510km without recharging. In 2015, it was the best-selling luxury automobile in the US having overtaking all brands of Lexus, BMW, Audi and Mercedes. In addition, it is not that difficult for motorists to connect their vehicles to stationery power stations to fast charge their batteries.
The real challenge for electric vehicles, be they battery or fuel cell powered, is that the developed world has made over a century of investments into a mammoth infrastructure built around the internal combustion engine: gasoline refuelling stations, engine factories, maintenance and repair shops, not to mention oil refineries; and it will cost massive sums of money to convert it for these sleek new electric cars. And let’s be clear there will be continuing resistance from that combustion engine value chain but with automobile manufacturers like Daimler and new entrants such as Apple and Google likely to follow Tesla’s lead into EVs it may be thankless task to prevent the electrification of transport. A better and more sustainable strategy is to embrace the changes going on in transport.