In a few decades the internal combustion engine will be to transportation what the typewriter is to typing today. It’s kind of mind boggling, but there is really no alternative if we want to stop increasing the CO2 concentration in our atmosphere.
Currently gasoline has about 50x more energy per unit weight than a tesla battery pack.
Battery energy densities have tripled in the past 10 years. Keeping on that pace, it would take over 30 years for batteries to be competitive with gas.
When you account for the astoundingly bad efficiency of ICE, though, the gap in usable energy decreases. This is why a tesla can go 300+ miles with a battery that can only store the same energy as 2.4 gallons of gas.
You're likely to hit a hard limit to what battery energy density can reach. The next step will be fuel cells which don't have the efficiency limits of traditional internal combustion.
The Tesla can go 300 miles by making it light, aerodynamic, brakes that recharge the battery, not turning on the heater, etc. Yes, it's a significant engineering accomplishment, but in the heavy long haul world when analyzing break-even points what matters is range improvements due to an increasing energy/weight ratio, not range improvements due to reducing air resistance and inertia. This is because the form factors of the boxcar are basically set by shipping container needs and the weight is going to be determined by the load you are carrying. Munro is advocating for hydrogen powered trucks and planes as hydrogen has similar power/weight characteristics to gas -- electrification of these is going to be a challenge.
If there's one thing that EVs are not, is "light". Model S ranges from 4,561 to 4,941 lbs. A model 3, 3,648 to 4,250 lbs. A Nissan Leaf - 3,538 to 3,946 lbs.
In comparison, a Honda Civic weights 2,771 to 3,012 lbs.
Regenerative breaking is nice but it's very dependent on the particular drive and terrain. Heaters are power hungry as there is very little waste heat that can be used (again, due to the high efficiency), unless they are heat pumps.
The main reason they can go so far with so little energy is the efficiency of electric motors.
> as hydrogen has similar power/weight characteristics to gas
No it doesn't! It has horrible energy density per volume, compared to any gas or liquid fuels. You can improve this by using high pressures (energy loss) or cryogenics (even more energy loss). But it's pretty bad to begin with. Turns out that the best way to store hydrogen is by adding some carbon atoms to it.
> If there's one thing that EVs are not, is "light".
sigh
Obviously we are not comparing about the weight of an EV compared to an apple or vehicle that doesn't require a battery. We are talking about extreme measures taken to make the car lighter so it can improve range. Replacing cheaper steel with more expensive aluminum, reducing even surface area of plastics, reducing wires. Truly amazing steps were taken to reduce weight.
> No it doesn't! It has horrible energy density per volume,
volume? Seriously?
"The energy in 2.2 pounds (1 kilogram) of hydrogen gas is about the same as the energy in 1 gallon (6.2 pounds, 2.8 kilograms) of gasoline."
https://afdc.energy.gov/fuels/hydrogen_basics.html
You're comparing mass to volume in that last paragraph there. Based on a quick google search, that 1 kilogram of hydrogen is going to take up 3.4 gallons as a cryogenic liquid—so even more as a compressed gas.
> Obviously we are not comparing about the weight of an EV compared to an apple or vehicle that doesn't require a battery.
Well, yeah that was my original intention. Teslas get comparable range to ICE vehicles while using less than 3 gallons of gas. That comparison to ICE vehicles demonstrates the efficiency of electric vehicles.
People have hard time grasping how much energy chemical bonds can hold. 15 gallons of gasoline store 500kWh of energy. That is 5 tesla model s worth of energy.
Efficiency plays role for our day to day car tasks, but when you have to deal with external forces or higher requirements of momentum, then you need more energy period. Towing, beating high-speed drag / waves, climbing high, cannot be addressed with smarter design. You need to be able to store somehow enough energy to deal with these external forces / additional required momentum
>Hydrogen works fine in ICEs with modest modifications.
Just that they get lower efficiency than a fuel cell version, and apparently are sensitive to load, so mostly suited to constant-load applications, which a car typically isn't. Otherwise it'd have been interesting as fuel cells also have some serious drawbacks and seem to develop very slowly.
> Hydrogen can be created with nearly any energy source: renewable, natural gas, etc.
Yes. Although efficiency is kind of bad, so it doesn't make sense to use fossil fuels to make H2 for cars - we'd just be increasing emissions as opposed to generating electricity for use in BEVs. H2 has its place as intermediate term (before batteries get cheap enough) energy storage of surplus wind and solar power. It makes more sense to use the H2 for other things than cars though - ships, trains, long-haul trucks, possibly planes.
>There is a large infrastructure for moving fuels.
Which I bet has to be seriously adapted to handle hydrogen. You wouldn't be able to move syrup with the existing infrastructure, because it's very different to gasoline. H2 is probably a lot more different - it needs much tighter seals, it embrittles materials such as steel, which is used everywhere for e.g. gasoline storage. It is cryogenic and under high pressure. Finally, it'd be stupid to lock ourselves into an energy storage tech that relies on a physical fuel that has to be transported around, when electricity is right there, partly built out already and requiring no physical trucks, trains, boats etc to get to the consumer. It's just stone age and the only reasons people think it sounds like a good idea is that they're so used to it working that way.
Pure EVs will reach a fundamental peak percentage similar to any other car class... Hybrid powertrains are really where the next 20-30 years are headed for the bulk of vehicles. Automotive racing and supercars have demonstrated hybrids are the most effective setup for the past decade, and barring some major breakthrough in battery tech that will all trickle down into consumer cars over the next 0-20 years.
> Hybrid powertrains are really where the next 20-30 years are headed for the bulk of vehicles
It depends what you mean by 'bulk'. I see a major future here for big trucks-- right now, 99%+ of our long-haul tractor trailer semis are pure ICE. There is no way to fully electrify that fleet quickly, so I believe hybrid tech is being seriously underestimated in this space (especially for retrofitting).
I've been expecting to see this emerge for over 5 years, I'm not sure what's taking so long. Likely it's a catch-22 of the industry being resistant to change, while large chunks of (reluctant) investor funded R&D are necessary to make it viable. In any case, I think some larger scale tests are finally being run this year, so I'm looking forward to the results of that.
As far as consumer vehicles go, well... we should electrify almost all of it. Simply the best choice for the majority of use cases. But that's going to take a while, and will affect battery availability, which is all the more reason why big trucks will need a longer transition phase that hybrids are perfect for.
Not sure I agree with that. I don't think you realize how many cars have switched over to hybrid powertrains, but are not advertised as a main selling point like the Prius or Volt. Volvo's entire lineup is now hybrid or electric along with their new performance brand Polestar. Mercedes is switching over to hybrid powertrains even on their AMG models. Audi's using hybrid powertrains even on their highest performance models like the RS6 and their ultra luxury vehicles like the A8. Hybrid technology is great for sports cars and offers many advantages over fully electric, most importantly being the weight savings.
I think the thinking on hybrids will shift from "smaller gas engine with an electric boost to help with merging on the highway" to "range extension option for the electric car." They'll be configured to not even fire up the gas engine until the battery pack is run down enough.
Hybrids are facing real challengers from a combination of PHEV, synfuel, hydrogen combustion and hydrogen fuel cell. While it is the ideal car of today I wouldn't be so sure about the next 20-30 years.
