Lingering questions about battery EVs signal that having a backup technology isn’t as crazy as it might sound
By Stephen Wilmot, The Wall Street Journal, July 16, 2023
…
This has become a consensus view: Fuel cell EVs, which are more energy-dense, are needed for long-distance trucking, buses and the odd niche light-vehicle application, while battery EVs, which are more energy-efficient, are the better solution for decarbonizing your typical family car…
…But behind the consensus linger questions, too, about battery technology—notably how fast it can realistically take over the family-car market. One well-documented worry focuses on limited supplies of battery metals such as lithium, and another concerns the impact of battery EV charging on the power grid. Hydrogen EVs, with their completely different supply chain, could ease these scalability problems, which have a sharp geopolitical edge given China’s dominance of battery supplies…
A virtuous cycle might finally be under way in heavy trucks. In time, this could in turn bring down the cost of fuel cells and hydrogen to the point that the technology becomes competitive with battery EVs in the car market, too — though this is still an outside bet given the potential of battery innovations…[end quote]
Of course, EV technology is only “green” if the manufacture of the batteries or hydrogen uses non-greenhouse gas releasing processes.
I think this is why Tesla delayed its Cybertruck production years after it was launched. I know TSLA is aiming to own the whole rails by exploring production setup in Indonesia to securing metals needed for batteries all around the world.
I’ve long thought that hydrogen fuel cell vehicles make a lot of sense. They most closely resemble our existing way of using cars, just with a different fuel.
My understanding is that the hydrogen itself is the big problem. It’s the most abundant element in the universe, but not easily accessible. While there is a really nice pool of the stuff 1 AU away, it’s kind of hot there.
Getting large quantities of hydrogen require prying it out of stuff like water (or fossil fuels - there we go again). This is more in your wheelhouse than mine, but I think it takes quite a bit of energy to break the chemical bonds holding hydrogen to other elements. More than you can get back by oxidizing the hydrogen. Hence it’s a net loss of energy to extract and then burn hydrogen.
Unless that problem can be solved (perhaps solar electricity to desalinize sea water followed by electrolysis to split the hydrogen and oxygen out) hydrogen as a fuel is probably limited to niche applications.
It is actually a bit worse than that. Because not only do you need electricity to make the hydrogen, hydrogen vehicles then use a fuel cell to convert the hydrogen back into electricity. So that never going to be more efficient than simply using electricity directly in the first place.
Hydrogen vehicles of course help solve the range problem of EVs. But another way to solve the range problem is a plug-in hybrid.
Plug-in hybrids solve another problem in that everybody wants range, but that requires a bigger, heavier battery which requires more energy to propel the vehicle. Some of that energy is generated by fossil fuels and will be for a long time to come. You also need more rare earth metals which are in short supply, and of course require energy to extract and refine.
Although you can’t 100% decarbonize with a plug-in hybrid, because most trips are short, you can mostly decarbonize and then have a high efficiency engine for the remainder.
For me, it’s not entirely about the efficiency. It’s about having enough stored energy with you to accomplish the trip, or being easily able to get more along the way. Hydrogen as a fuel accomplishes that reasonably well. Maybe not the “get more” part yet, as hydrogen stations are far rarer than EV chargers. But just like EV chargers, there’s no new tech we need to figure out. It’s just a matter of demand rising enough to encourage supply to be provided.
Or shorter: some loss of efficiency is fine if you get usefulness in exchange. And especially if you get the real prize - less CO2 and other harmful emissions.
Beats me. I’m an accountant, not a chemist. I have only an interested lay person’s understanding of chemistry.
However, as a guess, a fuel cell is a chemical reaction that produces electricity, whereas an ICE is basically a contained explosion. So the efficiency is probably a function of the machine. With all of the moving bits and pieces and the accompanying friction of an ICE, I suspect the fuel cell is more efficient in turning hydrogen into forward motion of a car.
A conventional combustion-based power plant typically generates electricity at efficiencies of 33 to 35%, while fuel cell systems can generate electricity at ef- ficiencies up to 60%
So, at first glance, appears the fuel cell has the advantage, once you have the H2 in hand.
Imagine some wheelbarrows filled with rocks. The rocks contain lithium, cobalt, manganese, nickel, graphite and other materials for lithium-ion batteries. By Toyota’s calculation, the amount of rocks needed for one long-range electric vehicle would be enough for either six plug-in hybrids or 90 of the type of hybrid that can’t be plugged in for a recharge. (Namely, the type whose batteries are recharged from the engine or from braking.)
“The overall carbon reduction of those 90 hybrids over their lifetimes is 37 times as much as a single battery electric vehicle,” Toyota argues. That’s a stunning statistic if true.
“Toyota’s claim is accurate. We’ve crunched the numbers on this,” Ashley Nunes told me. He is a senior research associate at Harvard Law School and the director for federal policy, climate and energy at the Breakthrough Institute, a think tank. He [testified] on the topic in April before the House Subcommittee on Environment, Manufacturing and Critical Materials.
Abundance (in the wrong chemical state ) isn’t a big advantage. And there are more electrons than hydrogen atoms…and we still have to generate electricity.
Hydrogen has some real advantages though. You can generate it multiple ways, though it seems only via electrolysis it is “clean,” and you can opportunistically generate when there is excess electricity available (i.e. wind and solar). But I would think that if its use was widespread no one would want their expensive electrolyzers sitting idle or underused for a good part of each day.
But the disadvantages are many. Much lower efficiency (thus higher cost) than electricity. You also need to compress and liquefy it which is a significant energy cost. You need high pressure tanks to store it. Look at the trunk space available in a Toyota Mirai and compare it to any EV.
So there is probably an opportunity for larger vehicles (semi trucks, industrial equipment) where size constraints aren’t as important and refuel time (compared to batteries) is important.
Efficiency
electrolysis: typically ~60%
compress and liquefy: 70%
fuel cell (H2 to electricity): 60%
net: 25% (not counting any storage losses or H2 delivery costs)
some sources say overall 25%-35%
It should be noted that currently 95% of H2 for industrial use and the few cars is produced via natural gas reformation. So I suspect that much fuel cell promotion comes from the obvious suspects.
battery
L2 charge: 90%
DOE says grid to wheels is about 60% counting all losses)
These are rough numbers. Find any better numbers via google. But you can see that it is at least 2x and maybe 3x worse than charging a battery.
Last time I heard this nonsense, John Petersen was writing articles over at Seeking Alpha pumping his own battery company while attacking Tesla. That didn’t work out well for him, lol. And, I’m betting it’s not going to work out well for Toyota, either. If Clayton Christensen were alive, he’d be working on yet another chapter about a hugely successful company that failed to adapt to disruption.
I’m not about to go point by point through Coy’s/Nunes’ arguments - their citing of 200kWh of batteries in cars for instance (only the outrageous Hummer EV has that much and GM only makes a few a week). My point is that looking at this in terms of rocks isn’t the correct approach. The issue is that after you’ve converted every car to a Prius, you’ve still got hundreds of millions of cars that pollute.
Let’s do some math of our own, shall we:
From the article’s data (which I doubt, but we’ll skip that for now), 90 Priuses save as much carbon as 37 BEVs. Do the simple math and that means it takes 2.43 Priuses to save as much carbon as a single BEV.
Let’s call the single BEV carbon savings “X.”
Now imagine a small town with 90,000 cars. Let’s say they replaced all of them to Prius-like vehicles, as proposed in the article. They would have saved 37,000 X of carbon.
Now imagine that only half the cars are replaced with BEVs. They would have saved 45,000 X of carbon. And more importantly, can still make progress towards replacing the other half of cars in the town!
And all this is even before analyzing the probably bad data that these number are based on, and that the electrical grid is getting cleaner every day.
That’s not quite what it said. It said that 90 hybrids save 37 times more carbon than a single BEV. So it takes 2.43 BEVs to save as much as one hybrid.
That’s quite a difference. Now, these lifetime carbon estimates vary wildly depending on who is doing the estimating. I don’t know how to even attempt to do it myself. So it is one of those things we just have to sort of trust (I’m totally open to hearing other estimates).
But one thing we know for sure is that BEV owner drive their vehicles quite a bit less than ICE owners. Which makes sense, because you won’t buy a BEV if you think range will be an issue. To combat this, BEVs need bigger, heavier batteries that require more materials processing and increase costs.
But to decarbonize, we need to decrease costs. PHEVs have lower upfront costs than BEVs. PHEVs also fix the range problem, so they are attractive to more buyers. But PHEVs don’t get as big a tax credit under the IRA because their batteries are smaller.
I’m just throwing spaghetti, but it appears PHEVs might be a faster approach to decarbonization than emphasizing BEVs. For now, anyway.
IMO, certainly if you do the math on miles typically driven PHEV would win. I owned a Prius plug-in for 11 years. (I’d still have it if the catalytic converter hadn’t been stolen a few months ago.) But I charged it almost every day. ~65% of miles were in EV mode.
But the problem is that it is difficult for subsidies to help sell PHEVs and achieve EV usage, in general. Lots of people bought PHEVs for the subsidies and/or the car pool stickers and did not provide the goal of lower CO2/smog since they just refuel with gas.
I couldn’t begin to make an estimate, but I will make the following points.
I believe Toyota’s estimate is correct, except it’s possibly quite wrong. I would find it easy to believe if it hadn’t used the word “lifetime.’ It’s obviously far more carbon intensive to produce a single 12v battery for a true hybrid than for a Plug In which requires several, and especially for a pure EV which requires a ton of them. So on the “1=6=90” equation from Toyota, easy to buy except for that word “lifetime” [“ The overall carbon reduction of those 90 hybrids over their lifetimes is 37 times as much as a single battery electric vehicle,” Toyota argues.”]
Still, most experts agree that you have to drive an EV 60,000-80,000 miles to get to “carbon neutral” compared to an ICE because of the relative difference in producing batteries which require lots of exotic minerals and an internal combustion engine which is pretty much a single, widely available metal (with a 150 year infrastructure producing ginormous quantities of it. Or aluminum, 75 year history.) I note that even that estimate ignores the pollution caused by tire degradation due to heavier cars, and road re-construction requiring infinite truckloads of asphalt, but that would be hard to guesstimate at this stage, I suppose. That’s not all due to EVs, of course, but it’s hard to see the chart going the other way anytime soon.
Likewise, the carbon savings of an EV depend greatly on how/where the electricity is produced. In Kentucky it’s likely coal, in Texas maybe wind/solar/nuclear. I have read that in coal country any carbon savings are a wash, possibly even slightly negative. (Not trying to be contentious, just stating some analyses I have read.)
In any event, your math is way wrong. The article may also be wrong, or it may be slanted by a clever parsing of facts from a company which finds itself late to the game and which would like to capitalize on the technology they’ve had in-house for 20 years in the face of a stunning revolution, at this point I don’t know.
I am not, however, going to discount the various arguments based on my personal wants (I’d like all cars to be EV, to have charging stations everywhere, for battery technology to be 100% better, for all power to come directly from the sun, and for rainbows and unicorns in every garage. But that’s not gonna happen, is it.)
Other funny factors include that EVs seem to be driven fewer miles (per capita) than ICE cars, so the carbon savings come slower. This may be a range anxiety issue (when taking long trips EV owners still use the ICE car), or it could be that EVs sell to mostly wealthy people who have access to more expensive transportation options (airlines) and don’t take long road trips, and so on. This is a complicated machine with lots of moving parts - but one thing I try not to do is have a visceral reaction when somebody says “it’s all good” or “it’s all bad”. I’d rather read a bunch of try to suss out the answer for myself. That’s why I posted the article, I thought it an interesting counterpoint to the reams of happy EV talk hereabouts.
CleanTechnica just did a response to a few nonsense articles on hybrids vs EVs, including the one linked above:
Which is obvious nonsense; no wonder I read it wrong.
As for the electrical grid, while the US isn’t uniform, the trend is unmistakable:
Even there, studies have shown that even when powered by coal, EVs are cleaner than ICE vehicles:
From Reuters:
For a Tesla, the carbon neutral point is 13,500 miles, according to Argonne National Lab’s published model.
The Tesla 3 scenario above was for driving in the United States, where 23% of electricity comes from coal-fired plants, with a 54 kilowatt-hour (kWh) battery and a cathode made of nickel, cobalt and aluminum, among other variables.
It was up against a gasoline-fueled Toyota Corolla weighing 2,955 pounds with a fuel efficiency of 33 miles per gallon. It was assumed both vehicles would travel 173,151 miles during their lifetimes.
and
Even in the worst case scenario where an EV is charged only from a coal-fired grid, it would generate an extra 4.1 million grams of carbon a year while a comparable gasoline car would produce over 4.6 million grams, the Reuters analysis showed.
and finally:
The results of the Reuters analysis are similar to those in a life-cycle assessment of electric and combustion-engine vehicles in Europe by research group IHS Markit.
Its “well-to-wheel” study showed the typical break-even point in carbon emissions for EVs was about 15,000 to 20,000 miles, depending on the country, according to Vijay Subramanian, IHS Markit’s global director of carbon dioxide (CO2) compliance.
So, most people break even during the second year of driving, and then it’s all savings for the remaining lifetime of the vehicle - with savings increasing as the grid gets cleaner and clearer each subsequent year.
But they didn’t rebutt any of those data. The just made some ad homenims. Like I said, I’d like to hear some more analysis. But they didn’t provide that. Which makes me think they might not have much…
While this is still true to some extent, it has been rapidly changing over the last 2 years. Tesla owners, for example, are much more willing to take long road trips now that the charging infrastructure has been developed. And, most tellingly, uberlyft drivers are choosing EVs in a much higher proportion than general use cars (this was quite surprising), and it all boils down to economics; at their very high miles driven, any EV is far more economical for them to operate, which means more net profit for them. Personally, in our family, we take the EVs over our ICE any time possible. It’s simply much less expensive to operate the EVs so why on earth would we want to take the ICE???
As far as my personal energy efficiency, I usually measure it in cost (money is a rough measurement of energy), and my EVs cost me a lot less than my ICEs did. And as far as overall cost in energy, look at it this way - today 2% of electricity comes from solar (call it “free fuel” as opposed to feeding gas into a burner to generate electricity), so let’s say 2% of the electricity used for EVs comes from solar. Use that in your comparisons, and of course wou will say that 98% comes from “other” (fossil fuels, hydro, nuclear, etc). BUT that 2% is growing, next year it’ll be 3%, and in 10 years it’ll be 15%, and hopefully in 20 years it’ll be 35%. So that EV, whatever the numbers are today, will inherently improve next year, and in 5 years, and so on. The ICE vehicle (which includes PHEV since a substantial number of PHEV owners rarely or never P it) will not. In fact, depending how difficult it is to extract oil, they will likely get less efficient over time.
I’m with you, but there is a perception problem. You’re not the one who needs to be converted, it is the people who don’t have EVs who are worried about range. And that’s why people who don’t drive a lot are the ones mostly buying the EVs.
