Imagine that you’re on a plane.
It’s been an uneventful flight and the pilot just announced he’s starting the descent from the cruising altitude of 35,000 ft.
Then, disaster strikes.
As the plane begins its initial descent, a freak storm comes out of nowhere and drives visibility down to zero. To make matters even worse, the pilot loses altitude data in the cockpit. Is the plane at 29,000 ft? 25,000 ft? Who knows!!
Given this scenario, who would you want flying the plane…
A pilot that uses every tool in the toolbox to understand how close the plane is to the ground, even if he doesn’t have perfect information.
OR
A pilot that descends with reckless abandon with no regard for how close he is to the ground.
Hopefully the answer is obvious.
Now, consider a second scenario.
You’re trying to predict the pace and scale of EV adoption. To do so, you can enlist the help of one expert. Who would you choose…
An expert who works carefully and methodically to understand the theoretical and practical limits of battery technology.
OR
An expert that assumes EV batteries are on a never-ending path of exponential improvements.
Is the answer obvious here, too?? If it is, then why do so many people listen to the second expert?
When it comes to projecting EV adoption, listening to mainstream environmental advocates masquerading as “energy transition experts” is like putting trust in a pilot that assumes they can descend in perpetuity without crashing into the ground.
We don’t doubt that environmentalists intuitively know that there has to be a limit. However, their ignore-the-ground advocacy is convincing the general public that the ground doesn’t exist.
For instance, consider Rocky Mountain Insitute’s (RMI) recent report, The Battery Domino Effect (emphasis added).
Rising energy density keeps unlocking new uses while declining costs enhance affordability and accelerate market uptake. This uptake, in turn, drives further cost reductions and continuous innovation — a cycle of self-perpetuating progress. The result is a domino effect, whereby batteries enter new markets, from country to country and from one sector to the next. Geopolitical tension has brought new players into the markets, speeding up the race to the top.
The pace of change keeps confounding experts, who consistently underestimate the potential and exponential growth of batteries.
You don’t think batteries will continue exponential improvements? You fool! As often happens, this non-thinking hype is reinforced by mainstream environmental advocates. Here’s Bill McKibben:
…the point of the RMI report is that this kind of progress is only going to continue
Let’s keep descending! There’s no way we’ll ever hit the ground.
If we ignore the limits of battery tech, we’ll eventually crash into the ground in a fiery explosion of excessive government spending and bankrupt companies.
Where’s the “ground?” To answer that question, you have to understand energy density. Let’s explore…
By definition, energy is the capacity to do work. What is work? A pain in the ass. Besides that, it’s also known as a job. Energy does a job. You can’t choose what energy source to use unless you understand what job it has to do. Just like you can’t choose an employee without understanding what job they have to do.
The “job” to be done in transportation is moving people and things, where the energy needed is governed by the fixed laws of inertia and friction. This is a fundamentally different job than, say, powering a flashlight.
When it comes to transportation, energy density is critically important - particularly energy per unit mass (aka specific energy). Moving heavy, physical objects is hard. You can’t afford to have your energy source weighing you down.
The fundamental constraint of energy density is why it’s so difficult for batteries to usurp the dominance of gasoline and diesel fuel in transportation. Let’s put some numbers on it…
The lithium-ion batteries used in today’s EVs have a specific energy of ~250 wh/kg while the specific energy of gasoline is ~12,888 wh/kg. Said another way, a kg of gasoline contains ~52x more energy than a kg of lithium-ion batteries!
But wait! The process of converting the energy contained within the battery to useful work is more efficient than the process of combusting gasoline — much of the chemical energy stored in gasoline is lost to heat when it’s burned. This is true! How does it change our calculus?
Here’s a rough way to look at it. 15.8 gallons of gasoline in a Toyota Camry can power the car for ~612 miles. If we assume the tank itself weighs ~30 lbs, the fuel + tank system weighs ~126 lbs. That means the Camry can travel ~4.9 miles for every pound of its fuel system.
On the other hand, a battery weighing ~1,060 lbs can power a long-range Tesla Model 3 for ~335 miles. That’s ~0.3 miles for every pound of fuel.
The Toyota Camry gets 16x more mileage per pound of fuel than a Tesla Model 3. The conversion efficiency of the EV drivetrain reduced gasoline’s advantage from 51x better to 16x better.
Will 16x eventually become 0x?
If not, why do so many people believe in 100% EV adoption?
In large part, our mass dissonance comes from environmental advocacy like that of RMI and McKibben that generalizes EVs as “tech.” Mark Mills explains the key difference between the energy industry and computing technology:
“The challenge in storing and processing information using the smallest possible amount of energy is distinct from the challenge of producing energy, or moving or reshaping physical objects. The two domains entail different laws of physics.
Batteries will improve, sure, but there are limits. Different battery chemistries are like landing in Miami vs Denver from the same starting point in the air. It might take you longer to reach the ground, but that doesn’t mean the ground isn’t there.
If we look to the future, solid-state and lithium metal batteries are said to potentially possess energy density 3x more than that of today’s EVs. So even IF these batteries-of-the-future take over, they’d still have an energy density 5x less than the fuel in ICE vehicles!
And to be clear, this is based on the incorrect assumption that gasoline vehicles see zero improvements in how efficiently the energy in gasoline is converted into motion.
We don’t say all of this to make the point that EVs are dumb. Far from it. EVs are pretty sweet. They work in some applications for some people. They reduce local air and noise pollution. They’re fun to drive. They’ll continue to improve. If you can afford a pricier car, can charge at home overnight, and do the vast majority of your driving in quick jaunts around town, you should definitely consider going electric.
We say all of this to make the point that EV adoption has a limit. If you want to take a stab at predicting that limit, you need to understand energy density. It’s not that hard grasp, it just might be inconvenient.
Don’t be dense, like this post!
This is such an important concept that is NEVER talked about in government/NGO circles when discussing the energy transition. In nearly 20 years of public service, never once had it considered when developing policy prescriptions by senior leadership. And don't get me started with McKibben...here is the substack I wrote about him a while ago.
https://energydiplomat.substack.com/p/the-shallowness-of-experts. It also happens to be my most read publication to date.
Nice piece. I've discussed some of the RMI work myself recently. It's clear that they are possessed with the exuberant energy transition ideology. They also believe wind and solar are on an S-curve to make fossil fuels obsolete in short order as well. It's nice to see others with a balanced approach who aren't dissmissive of batteries and their utility, but also understand the energy density (in your nice comparisons) and practical limitations. I look forward to more of your articles in the future!