Weight Matters

The saying goes that size matters – but weight matters more. If you want to go far. This is why EVs don’t. Even the really little ones – like Chevy’s Bolt, which is even smaller than a subcompact car like the Hyundai Accent – only go about half as far as their size-equivalents. Viz, 259 miles for the 3,589 lb. Bolt vs. 487 (on the highway) for the 2,679 lb. Accent.

That’s because a gallon of gas weighs about six pounds, which means a full tank of gas (12 gallons) in the Accent weighs 72 pounds. A great deal of energy is stored in those 72 gallons of gasoline – or even just six pounds. One gallon will power a car like the Accent some 40 miles down the highway and part of the reason for that is that as you burn it, there is less of it – and so, less weight to keep moving. After a car like the Accent has used up half a tank – about six gallons – it is carrying around half the fuel weight it began the trip with.

It takes a great deal more weight – that is never shed – to power an EV the same distance. A small EV like the Bolt is weighed down by the gas tank equivalent of about 1,000 pounds of battery pack – and in fact, it’s not equivalent, because the Bolt would probably need another several hundred pounds of battery pack to be capable of powering its electric motor for nearly 500 highway miles.

But for the sake of this discussion, let’s assume an equivalence.

It takes 1,000 pounds of battery to propel the Bolt the same 40 miles, because whether it’s fully charged or just barely, with the electric equivalent of only 40 miles of range remaining – it is always lugging around every ounce of that 1,000 pounds. An EV battery pack does not get lighter as it is discharged even though electricity is essentially weightless. But the storage medium – the battery – is not. No matter how much electricity you burn, the weight of the battery remains the same.

And that weight is always a literal drag on how far the EV can go.

To fully appreciate just how weight-wasteful EV battery packs are, let’s consider an equivalence. How far down the road would 1,000 pounds of gasoline take a car like the Hyundai Accent? Well, 1,000 pounds of gas at about six pounds per gallon works out to about 160 gallons of gas, or about 14 full tanks.

The Accent is rated by the EPA as being able to travel about 41 highway miles on a gallon of gas. Thus, the Accent could be driven some 6,560 miles on a “tank-equivalent” of one Bolt-sized EV battery pack.

This is why the Accent only needs to carry about 72 pounds (or 12 gallons) of gas to be able to travel almost twice as far as the Bolt. Put another way, the latter must lug around the energy equivalent of about 13 times the weight to be able to go about half as far.

If this is “efficient” – which we’re told EVs are – I’d hate to think what an inefficient EV would look like.

The usual retort is that EVs use less energy – i.e., electricity – to travel a given distance but this evades the issued of the weight needed to store that energy. Not to mention the quantity – of materials that go into every EV battery – as well as into producing the power for EV batteries – a subject this column has addressed previously. But the point as regards this topic is that weight is the natural enemy of efficiency and that is why EVs aren’t efficient. It is why it will be hard for them to ever be efficient.

It is the same reason why you do not see heavyweight athletes winning marathons. The latter are sometimes capable of explosive quickness, but only briefly. Just like EVs.

Long-distance runners – whether they are bipedal or mechanical – are always light.

But the dilemma as regards EVs is that they are all very heavy. And so always inefficient. This will remain the case absent an as-yet-unknown alternative way to store enough electricity to propel an EV even half as far as any non-EV that weighs 1,000 pounds less can go.

If a way could be found to store the energy equivalent of 72 pounds of gasoline in a 100 pound battery pack, then you’d have something very different. An EV like the Bolt would then weigh the same or even less than a non-electric equivalent like the Accent. It would not need a motor as powerful – and heavy – as the one that currently propels it in order to deliver the same performance, because it would be almost 1,000 pounds lighter. And for that reason, it would be vastly more efficient. It would probably be able to travel at least as far as the Accent can and perhaps even farther on less electricity than the current Bolt burns up to travel about half as far.

But there is no indication that such a “breakthrough” is imminent. Instead, EV batteries are being made even larger – and heavier – in order to store enough power to propel electric trucks and SUVs rather than cars, because cars have only so much room for batteries and so only have so much range. You can put more battery in a big truck. But then it is a heavier truck – viz, the three-ton half-ton pick-up, Ford’s F-150 Lightning – and it doesn’t go very far, either. But it can tout quickness (briefly) and capability (also briefly) so as to distract attention – look! a squirrel! – from its built-in inefficiency.

It’s like expecting someone to win the Boston Marathon with a 100 pound plate from the gym strapped to his back.

Worse, it’s like pretending such a thing is even possible.

Eric Peters lives in Virginia and enjoys driving cars and motorcycles. In the past, Eric worked as a car journalist for many prominent mainstream media outlets. Currently, he focuses his time writing auto history books, reviewing cars, and blogging about cars+ for his website EricPetersAutos.com.

Editor’s Note: The opinions expressed in this article are those of the author.

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