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What I don't understand is how we didn't have these efficiency numbers in terms of kwatts/mile with an ICE/EV hybrid drivetrain, and why we haven't had them for

What I don't understand is how we didn't have these efficiency numbers in terms of kwatts/mile with an ICE/EV hybrid drivetrain, and why we haven't had them for decades already. Why aren't hybrid drivetrains in Semis, RVs ... everything. Within 5 years of the Prius there should have been legislation mandating PHEVs for practically all consumer transport. With a hybrid you can run an engine in the Atkinson cycle which (apparently) enables diesel-level mileage out of gasoline. You get the regen braking that dramatically improves city driving. Every five years after the Prius is another travesty that we didn't have this legislation coming down the pipe. By now in 2022, 25 years after the Prius and Insight, we should have had 50% or more of new cars being PHEV hybrids with 50+ mile all-electric range. It would have brought Russia to its knees, the Saudis would be an afterthought in policy, and we'd be so much more resilient. And hybrids in addition to atkinson should enable other tricks for efficiency gains besides carnot output to reclaim heat from the engine and exhaust, like turbochargers do. Gas turbines at the utlity scale are at 60% efficiency. Oh well.

josephcsible 4y ago
> By now in 2022, 25 years after the Prius and Insight, we should have had 50% or more of new cars being PHEV hybrids with 50+ mile all-electric range. The problem with PHEVs is that so many people never plug them in, unless the automaker does something to them like with the BMW i3 REx, in which case said people wouldn't want them.
- AtlasBarfed 4y ago
  This is education and habits. And when gas is at $5.00, an economic incentive.
  - pornel 4y ago
    It's also a practical difficulty. Small batteries in PHEV mean they charge slowly (makes public chargers less useful, EV road trips impossible). Their tiny EV range requires them to be charged daily, which makes at-home charging a necessity in practice. But having such a good access to charging is also a thing that makes BEVs convenient. From this perspective PHEV a poorly-performing BEV with a baggage that reduces its performance, range, and efficiency, and occasionally is a less-efficient ICE to potentially save 20 minutes of time after 2-3 hours of driving at highway speeds.
    - AtlasBarfed 4y ago
      I agree that PHEVs are fundamentally a flawed BEV. I was pretty strident in the belief, until someone pointed out that when you consider the scale of moving consumer transportation to batteries with current battery production scale (even with the scaling of battery production over the next five years) is SO BIG... The best use of available battery supply is to do PHEVs. For city traffic you get a huge gain in all-electric driving. But really, this would have required forethought about 10 years ago to push car makers to have the scaled production ready for hybrid drivetrains. They don't, and so what I think is that all-BEVs will transition in. What really sucks is that if we had hybrid drivetrains in mass production ten years ago in most consumer transport, then the used car market would now be full of them. As it stands, BEVs will come in the new cars, but dirty ICEs will stick around for a decade at least. It would have been so nice for that used car market to be PHEVs.
mhh__ 4y ago
Hybrids are really complicated to build. F1 engines have something called an MGU-H which recovers thermal energy from the engine (turbocharging) but can also spool up electronically etc. They can reach something like 50% thermal efficiency, but these are truly complicated machines.
- AtlasBarfed 4y ago
  I'm obviously not an automotive engineer... but... 1) electric motors are very high torque 2) electric drivetrains aren't really that complicated. 3) the hybrid battery isn't that large, so it's not the space for that 4) all the engine has to do is recharge the battery. Mazda could have probably done a rotary or honda done a miraculous small engine to do the recharging. Sure I get that the early hybrids were complicated, they probably had both the electric drive and the engine delivering power and balancing things. But with skateboard design EV platforms (and that is over 10 years old at this point), the industry would have produced a very efficient and likely cheaper than a traditional big engine ICE platform with incentives and regulations by now. It probably is moot now. 200 wh/kg at pack level LFP is coming into mass production, and 150 wh/kg sodium ion is coming next year. But for midwesterners, long haul truckers, RV drivers, and other long distance frequent drivers, the 50 mile PHEV with 200 wh/kg LFP should have a ten year lifespan and deliver carbon emissions savings. But... oh well.
_ph_ 4y ago
You are completely right, for 20 years most of the automobile industry built cars that used more energy and especially polluted more than it would have been necessary if they had copied the technology of the Prius. Our environment would look much better now, if they had. But in my eyes, the time for hybrids is over, any new car should be pure electric as it is simpler and way more efficient.
deleted 4y ago
[deleted]

josephcsible 4y ago

> By now in 2022, 25 years after the Prius and Insight, we should have had 50% or more of new cars being PHEV hybrids with 50+ mile all-electric range. The problem with PHEVs is that so many people never plug them in, unless the automaker does something to them like with the BMW i3 REx, in which case said people wouldn't want them.

AtlasBarfed 4y ago
This is education and habits. And when gas is at $5.00, an economic incentive.
- pornel 4y ago
  It's also a practical difficulty. Small batteries in PHEV mean they charge slowly (makes public chargers less useful, EV road trips impossible). Their tiny EV range requires them to be charged daily, which makes at-home charging a necessity in practice. But having such a good access to charging is also a thing that makes BEVs convenient. From this perspective PHEV a poorly-performing BEV with a baggage that reduces its performance, range, and efficiency, and occasionally is a less-efficient ICE to potentially save 20 minutes of time after 2-3 hours of driving at highway speeds.
  - AtlasBarfed 4y ago
    I agree that PHEVs are fundamentally a flawed BEV. I was pretty strident in the belief, until someone pointed out that when you consider the scale of moving consumer transportation to batteries with current battery production scale (even with the scaling of battery production over the next five years) is SO BIG... The best use of available battery supply is to do PHEVs. For city traffic you get a huge gain in all-electric driving. But really, this would have required forethought about 10 years ago to push car makers to have the scaled production ready for hybrid drivetrains. They don't, and so what I think is that all-BEVs will transition in. What really sucks is that if we had hybrid drivetrains in mass production ten years ago in most consumer transport, then the used car market would now be full of them. As it stands, BEVs will come in the new cars, but dirty ICEs will stick around for a decade at least. It would have been so nice for that used car market to be PHEVs.

mhh__ 4y ago

Hybrids are really complicated to build. F1 engines have something called an MGU-H which recovers thermal energy from the engine (turbocharging) but can also spool up electronically etc. They can reach something like 50% thermal efficiency, but these are truly complicated machines.

AtlasBarfed 4y ago
I'm obviously not an automotive engineer... but... 1) electric motors are very high torque 2) electric drivetrains aren't really that complicated. 3) the hybrid battery isn't that large, so it's not the space for that 4) all the engine has to do is recharge the battery. Mazda could have probably done a rotary or honda done a miraculous small engine to do the recharging. Sure I get that the early hybrids were complicated, they probably had both the electric drive and the engine delivering power and balancing things. But with skateboard design EV platforms (and that is over 10 years old at this point), the industry would have produced a very efficient and likely cheaper than a traditional big engine ICE platform with incentives and regulations by now. It probably is moot now. 200 wh/kg at pack level LFP is coming into mass production, and 150 wh/kg sodium ion is coming next year. But for midwesterners, long haul truckers, RV drivers, and other long distance frequent drivers, the 50 mile PHEV with 200 wh/kg LFP should have a ten year lifespan and deliver carbon emissions savings. But... oh well.

_ph_ 4y ago

You are completely right, for 20 years most of the automobile industry built cars that used more energy and especially polluted more than it would have been necessary if they had copied the technology of the Prius. Our environment would look much better now, if they had. But in my eyes, the time for hybrids is over, any new car should be pure electric as it is simpler and way more efficient.

deleted 4y ago

[deleted]