Facts on adoption of electric vehicles

[TMac]

If you think of a car as a transportation tool, there is nothing wrong with an EV. If you are a urban or suburban driver who commutes a short distance back and forth to work, it's an ideal machine assuming you have a small battery pack and can plug it in at home or work. Of course, you'd have to rent for the occasional long trip, but how often are you really driving a thousand miles for vacation?

The big problem is that for the most part, that's not the vehicle the car companies are making. They went for the high range, high horsepower vehicles requiring extremely large battery packs they could charge a fortune for and the government- once again putting their fingers on the scale of the market- is helping them out.

I worked as lead engineer to develop a small (1000cc) engine weighing in at 50kg soaking wet and producing 58kw of power. It had very high BSFC numbers with 14:1 compression, a unique bridged intake port, and a novel adjustable cam timing and duration mechanism. That engine was capable of propelling a modern sedan at 70mph at nearly 50mpg. Pair that with the right electric motor(s) and a small battery pack and you have a vehicle that could still commute 30 miles on electric, get 50mpg on cruise control, accelerate from 0-60 in less than 4 seconds and weigh only 200lbs more than a similar gas vehicle with equal performance.

Unfortunately, the investors pulled out of the project when they saw where the "market" and government intervention was leading- an all electric car that had 300miles of range. No ICE allowed.

The problem isn't electric motors, it is the known disadvantages (as @MikeyP wrote) and the unknowns disadvantages of battery technology and the grid to support it.

Don't even get me started about the concept of the US shipping industry moving to electric semi tractors!!!

 

[TMac]

There are some assumptions: First, a modern diesel tractor (per federal law) can weigh 80,000 lbs total. Of that amount, 42-48,000 lbs of cargo. It requires an average of 225 kw to move a full load down the road at 65 mph. So, for an 8 hour driving shift we'd require a battery pack of at least 1800 kwh of battery- since we can't deplete the battery to zero,give ourselves about a 10% safety figure 2000 kwh of battery.

On diesel, we'd require (at 5 mpg) around 120 gallons to achieve the same energy density with about 10% leeway and that "battery" mass at 7 lbs/gallon = 840 lbs.

On electric, (using a 2024 tesla model y battery pack as a benchmark) we have an 81 kwh battery weighing 771 kg. Dividing 2000 kwh by 81 = 24.7 battery packs * 771 kg = 42,000 lbs of battery pack. I think this number speaks for itself- you'd only have about 3,000 kg of available cargo capacity! How many more trucks and drivers would you need on the road to haul the same amount of cargo? Or perhaps the truckers can use a smaller battery pack and stop every 4 hours for the 2 hours to recharge?

Also, that gigantic battery pack for a single truck would require over 500 lbs of lithium, around 770 lbs of cobalt, and around 1100 lbs of manganese.

Now do the math on replacing the over 4 million semis in the US with electric.

 

[TMac]

You can do the math on your own about the amount of lithium, cobalt, and manganese that would be necessary, but think abut this: The entire US grid in 2023 produced around 4.18 trillion kwh. Just those semis on eight hour shift would require over 11.2 billion kwh. Over one year, 11.2B * 365 = 4.08 trillion kwh- or the entire grid as we it exists now would have to be doubled just to operate our electric semis 8 hrs a day for a year. Or, the equivalent of 8.4 BILLION homes.

If we return to our previous example of diesel trucks, we would have 4 million trucks operating an 8 hour shift at 120 gallons per shift or 480 million gallons of diesel. How about how much liquid equivalent would be needed to generate electricity then go to the grid?

If we look at that replacement electricity by fossil fuel we require .08 gallons per khw, meaning that 11.2 billion kwh would require the equivalent of 896 million gallons of diesel. Does this make it clear that given current battery technology that this is a pipe dream?

 

[TMac]

So, if you've done the math, we'd need approximately 5.6 million * 770lbs of cobalt = 4.36 billion pounds. Worldwide cobalt production? 440 million lbs. So only about 10% of the cobalt needed. Manganese- no problem. As discussed, lithium = 5.6 million * 500 lbs = 2.8 billion lbs. World wide lithium production? 330 million lbs. Only about 12% of what's needed.

 

[TMac]

One might argue that in the US, only 65% of electricity is generated by fossil fuel. Even so, if we calculate that percentage by the electricity needed, we'd still be measuring around 580 million gallons of diesel- vs 480 million gallons of diesel in the non battery powered semi trucks. So where is the "green" savings?

I am absolutely not opposed to electric vehicles- as I posted earlier, they are yet another tool and there is absolutely nothing wrong with consumers buying what they want. The problem is with mandated use, especially when that mandated use is not in any way fixing the problem.

There are 281 million personal vehicles registered in the US (in 2022) - 70 TIMES more than the 4 million semis. I'll leave it to you to do the calculations to convert all of those to electric vehicles given the figures I posted earlier. Once again, battery technology is simply no where near where it needs to be to put those on the grid.

BTW, wind turbines are the most effective way to put electricity to the grid, and we'd need 340,000 more of them, all running at the same time, and all in windy areas, and somewhere close to grid access to meet 75% of demand just for the tractor trailers. And just FYI, we average about 3000 wind turbines added per year.

 

[TMac]

For those of you who read my posts earlier, I made a mistake in the first post. I had put the Tesla "Y" battery pack with 81 kwh at 771 lbs. In fact it was 771 kilograms, or 1700 lbs. Makes the point about electric not being remotely useful in long haul trucking even more convincing.

It should be noted that there are different battery technologies that are being used today which use less cobalt and more nickel or aluminum although lithium content remains about the same. Here are breakdowns of various newer technologies for a 60kwh battery pack.