Electric vehicles – an overview

Electric vehicles of all shapes and sizes have been developing so quickly over the last few years that it’s hard to keep up with the changes. This survey pulls together information on the current state of play of all sorts of EVs, from bikes and scooters to freight trains and ships. But first, a quick look at three technological issues common to all of them.

Basics

Batteries

Batteries are crucial, and development is still pushing ahead quite quickly.

Lithium-ion batteries are now the standard technology but the older lead-acid batteries are still installed where price is more important than performance, while newer technologies, e.g. sodium-potassium and lithium-sulphur, are showing promise.

Lithium-ion batteries are still improving (e.g. researchers tweak charging cycle to extend battery life) and getting much cheaper. (The price drop has in fact paralleled the falling cost of solar panels, doubling the good news for the environment.)

There is a trade-off, in all categories of EV, between range on the one hand and battery weight and cost on the other. The result is that EVs are most cost-effective in high-mileage urban roles, where distances are small so batteries can be smaller and cheaper, recharging is easy and substantial fuel savings repay the upfront cost more quickly.

Hydrogen

Hydrogen power has been developing alongside battery technology, and competing with it. Briefly, “Hydrogen stored in the hydrogen fuel tank reacts with oxygen in the fuel-cell stack and produces electrical energy, heat and water. The heat and water goes out the exhaust pipe as water vapour … and the electricity either goes straight to the electric motor or to a [small] battery that stores the electricity for when the vehicle requires it.” (That’s from a good introduction to hydrogen fuel cell vehicles on CarsGuide.)

There is still a possibility that hydrogen fuel-cell technology will out-compete battery electric tech at the heavy-vehicle end of the market but it seems to be losing at present.

That is probably a good thing. The fuel has significant inherent drawbacks which will limit its usefulness except in specific applications (there’s a good overview here). Also, and perhaps more troublingly, promotion of hydrogen seems to have been a greenwashing strategy of fossil fuel producers (those three links go to three quite different perspectives on the issue) and its environmental benefits have been widely and systematically over-hyped.

Conversions

Enthusiasts have been converting ICE (internal combustion engine) vehicles to EVs for years but it’s now going almost mainstream. For instance, Forbes reports that retrofitting is about to take off in France, driven by car owners caught between clean air regulations and the shortage of cheap electric cars.

And it’s not just cars. In their article about New York City repowering a few diesel buses, CleanTechnica notes that, “These repowered school buses in New York also might be the first of an oncoming tidal wave of repowered diesel to electric buses. The companies SEA Electric and Midwest Transit Equipment just announced an effort to repower 10,000 buses over the next five years,” and that, “Lightning E-motors, for example, takes brand new Ford Transits and converts them to electric transit vans.” (Links are CleanTechnica’s.)

Light vehicles

bicycles and step scooters

Electric bikes now make up a large percentage of the market. Among the torrent of stats on eBicycles.com are, “In 2018, more than half of all adult bikes sold in the Netherlands were electric [and] Spain witnessed a 55% annual increase in e-bike sales.”

Bike Exchange advertises a broad range of current and second-hand e-bikes (this is not an endorsement – it’s just an easy site to browse). Configurations? Anything you can think of: mountain, touring, road, city, cargo, folding, men’s, women’s and unisex. Prices range from around $1 200 to $10 000 and above; bottom of that range is a no-name basic bike with a 250W motor and 7 Ah battery, while fancier bikes offer gears, suspension, more powerful batteries and motors, lighter frames, better brakes, etc.

E-bike in Hobart
Everyday transport – an e-bike, no longer new

Is a scooter a vehicle? A lot of (mostly young) people use them in the same way we have always used bikes. And with a top speed of 50 kmh, capable of carrying 100kg, some of them need to be taken somewhat seriously. One with a 48V lead-acid battery and 1000 W motor (and a pop-up seat, which almost makes it a bike) will cost you $800 – $900, while one with half the specs will be half the price. Tech Radar has a ’10 best’ list here to inspire you.

Motorbikes and scooters

Electric motorbikes have been around for ten years or more but they are still struggling to compete with ICE bikes.

Plug in, ride out: Best electric motorbikes of 2021 comes from Motorcycle News and I’ve chosen it because its benchmarks are the ICE equivalents of the e-bikes it liked, rather than other e-bikes. Reading the article and browsing the linked reviews (this one is especially relevant), it becomes clear that battery weight, capacity and cost are problematic at the sport-touring end of the market.

However, electric bikes and scooters are already  highly competitive for urban commuting, especially as daily mileage increases. Scooters are used as taxis in Bangkok so a trial switching the fleet to battery power is a smart idea.

Small batteries limit a scooter’s range but they can be removed for charging in any convenient location, something that’s particularly useful where owners have to park on the street. They also make a commercial battery-swap scheme practicable.

Ultra-light cars

Most of the electric cars we read about (or see) are relatively large, powerful and luxurious. This intriguing article argues, however, that globally the future is going to be dominated by tiny cars – essentially street-legal golf buggies, or motorbikes with bodywork. It’s probably correct, too, since most people in developing nations (i.e., most people in the world) simply can’t afford the kinds of personal transport we take for granted in Australia. (The world really can’t afford it, either, even if the ‘fuel’ is renewable, since the embodied energy is unsustainable. But that’s a different and much larger question.)

Passenger cars, 4WDs and utilities

The global picture is very positive. The IEA’s Global EV Outlook 2021 notes that, “Electric car registrations increased by 41% in 2020, despite the pandemic-related worldwide downturn in car sales in which global car sales dropped 16%. Around 3 million electric cars were sold globally (a 4.6% sales share), and Europe overtook the People’s Republic of China as the world’s largest electric vehicle (EV) market for the first time.”

However, both this ABC overview (January 2022) and this article on The Conversation (March 2022) suggest that most Australians won’t be buying EVs this year or even next, primarily because of a lack of coherent government policies encouraging uptake. Most manufacturers are not moving very quickly either. This survey (late 2021) shows many of them planning for 2030 – 2040, with Toyota, the laggard, planning for 2050; and they are starting with their biggest markets, so Australia may end up with the last of their ICE vehicles.

Bonuses

One bright spot is that fleet owners have noticed that high-mileage roles favour EVs, e.g. Prius Taxi Belts Out Half a Million Klicks and Ride-share fleet to go electric.

Thinking of an electric car as a big battery on wheels leads to thinking of other uses for it. ‘Vehicle to load‘ capability is very simple and allows the owner to use the car or van as a mobile power supply (tradies will love it, and it’s what I suggested for electric camper vans recently). ‘Vehicle to Grid‘ uses the car battery as storage for a PV system. Typical home batteries have capcities from 4 – 16 kWh while most car batteries are over 20 kWh, so capacity is more than adequate (even a 6.5 kWh motorcycle battery would do the job).

Part 2 of this survey (to come) will look at heavier vehicles, from delivery vans up to semi-trailers, trains and ships. Yes, they are all going electric – as indeed they must if we are to reduce our CO2 emissions to net zero.

A glimpse of the future

But I will finish for now with the first commercial next-generation electric car, one that may only need a charger every few months because solar panels cover its roof, bonnet and tail and can harvest up to 12km of range per hour. It has just been previewed on Drive and I have swiped their photo because I couldn’t resist it.

Dutch EV showing solar panels
More than a daydream

One thought on “Electric vehicles – an overview”

Leave a Reply

This site uses Akismet to reduce spam. Learn how your comment data is processed.