this post was submitted on 20 Feb 2024
141 points (90.3% liked)
Technology
59174 readers
2161 users here now
This is a most excellent place for technology news and articles.
Our Rules
- Follow the lemmy.world rules.
- Only tech related content.
- Be excellent to each another!
- Mod approved content bots can post up to 10 articles per day.
- Threads asking for personal tech support may be deleted.
- Politics threads may be removed.
- No memes allowed as posts, OK to post as comments.
- Only approved bots from the list below, to ask if your bot can be added please contact us.
- Check for duplicates before posting, duplicates may be removed
Approved Bots
founded 1 year ago
MODERATORS
you are viewing a single comment's thread
view the rest of the comments
view the rest of the comments
This is actually one of the reasons why I push PHEV right now.
Note that PHEV has roughly 1/5th to 1/10th the battery size of a full EV. While every PHEV is different (do your research), the Prius Prime 2024 is perhaps the most practical. The new model has ~40ish miles of all electric range, and a button that can put you in 100% EV mode even at highway driving (at severe costs to your acceleration however: 0-60 in 11+ seconds in pure EV mode, while 6.5 seconds in EV+ICE mode). Still, the "pure EV" mode works on the Prius Prime, as crappy an experience as it is. This isn't true for all cars (ex: Honda Accord 2014 PHEV switches to 100% ICE on highway driving).
In any case, the Prius Prime proves that a 13.6kW-hr battery pack is sufficient to cover a daily commute up to 44mi (EPA rating all-electric range). No need to buy a 5x larger pack like a Tesla (78kW-hr) or a 18x larger pack like a Hummer EV (260+ Kw-hr).
All PHEVs have an effective "generator" that converts gasoline into electric charge for your battery pack, and operates at far greater efficiencies than a regular car (gasoline -> motion is less consistent than gasoline -> tuned-generator -> electricity). Furthermore, most PHEVs (though not all) rely upon Atkinson cycle, meaning the engine is more efficient to begin with. (less fuel is injected per cycle, losing low-end torque. But the low-end torque is supplemented with EV engines so its a fine tradeoff for far greater efficiencies). So even in 100% gasoline mode, a PHEV offers substantial emissions savings off of a regular car.
Ex: Most cars waste their energy at idle. PHEVs instead run the generator to charge up the battery pack, so that your car has "effective work to do" rather than wasting fuel at a red-light. When the batteries are full, PHEVs and Hybrids can shutoff the engine entirely at each Red-light (0rpm electric engines are powerful enough to start the car / accelerate inside a city without any ICE assistance), so all the idle-fuel waste of a traditional ICE in stop-and-go traffic is eliminated. Etc. etc. etc.
I agree with you that PHEV is the sweet spot for some people like me. I go on road trips multiple times a year and until I can charge up in 5-10 minutes, I don't see full EV as an option for my family. Also the lifespan of the batteries is a concern. You can have maintenance done on an engine to make it last as long as you want but batteries just need to be replaced at the end of their life. Eventually you reach the point where the battery replacement cost exceeds the cars value.
Yes. Fortunately, the cost of this is predictable.(Capacity of the true battery x durability) / kwh-per-mile == miles of durability.
Different batteries have different durabilities: anywhere from 800 cycles to 3500 cycles is a reasonable guess.
Wth the new crop of 3000-cycle LiFePO4 cells at lower costs, the estimated cost per mile of electric driving is reasonable today IMO. But run your calculations and make your own decision. Different vehicles have larger true battery sizes than advertised as well, so finding the 'True Battery Capacity's is harder than expected, but assume a 10% bonus or so if you don't know
Especially run this math on solar battery systems, where it's obviously not worth it to me at least. But electric cars are competing vs more expensive gasoline prices, so it's actually a reasonable cost in this more expensive use case.