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points by tarpitt 1 day ago | 0 comments

I own a pretty typical phev sedan (Gen 2. Volt), and I use more electricity on my 20 mile commute than the rest of my power usage combined.

All cars just use a ton of power moving a lot of mass. It is actually impressive, it's like 100KW at full tilt. I think i saw someone do the math for how much power transfer you would need to get EV charging as fast as gasoline refuelling: It's in the megawatts.

The only way you could signifigantly reduce power usage of vehicles is to reduce mass dramaticially with a motorcyle or autocycle. The Aptera is an interesting autocycle design based on this line of reasoning, but we are also seeing the emergence of a lot of electric motorcycles.

[–] spaceywilly 1 day ago

Yep, having each individual person commuting in their own car is just not that efficient in general. Another data point that amazes me is the NYC subway uses 4-5 million kWh per day. Sounds like a lot until you realize that around 4 million people ride it every day, that’s about 1kWh, or maybe like 20 cents of electricity, per rider. A person commuting 35 miles in an EV would take about 10 kWh daily. They’re never going to beat the efficiency of public transportation.

Also regarding filling up an EV as fast as gasoline, there’s a company in China that has demonstrated charging from 20-80% in 5 minutes. They’re using 3MW charging.

It makes you realize why gasoline has been so popular for so long, you can stop for 5 minutes and dump 500 kWh of energy into your tank. Unfortunately most of that is wasted as heat during the combustion process.

[–] scottyah 1 day ago

The subway has some great efficiency gains because it's use is so narrow. It can only transport humans and small amounts of luggage, and only goes from point to point with no variability or any real use for transporting any of the materials those people need to survive. You're just dumping the costs off to other areas.

Also, if you factor in the construction, idk what the timeline to pay that off would be.

[–] eldaisfish 1 day ago

ok, so then you should also factor in the environmental destruction cause by building roads, the cost of the roads, the environmental cost of burning petrol, the environmental damage of extracting and refining petroleum, and so on.

[–] NetMageSCW 1 day ago

I thought the comparison was to a BEV, not ICE.

[–] tarpitt 1 day ago

>Also regarding filling up an EV as fast as gasoline, there’s a company in China that has demonstrated charging from 20-80% in 5 minutes. They’re using 3MW charging.

Yeah that's the exact post I saw. I didn't believe the video at the time but I suppose it's possible with enough battery paralellism and cooling.

https://www.thecooldown.com/green-tech/new-ev-technology-cha...

[–] sourweasel 1 day ago

In addition to the Aptera, I think there's a potential market for the enclosed 2-wheel vehicles also like the MonoRacer. The aerodynamic efficiency gains of enclosed cabin motorcycles is huge and greatly improves range, especially at highway speeds. I'd like to see something similar at a lower price range and produced in greater volume.

https://www.peravescz.com/electric-version/