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Comment by samstave | Hacker News Reader

I always thought it would be cool if they did in-road charging, like a slot car.

Or, at least have this feature at the charging stations - instead aof a group of ~8 pods with typical cable connection trope like that of a gas-line seems like it could have been improved upon? How complex are the actual charging "pumps"?

Finally, It would be really interesting if some scrappy engineer in a city with overhead MUNI power lines to add a pole to a tesla to slurp power off those line (although clearly they would be fined - but it would be a cool PoC-hack.

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> How complex are the actual charging "pumps"?

150 kW per supercharger.

So your typical 8-pod supercharger needs to supply 1.2 MW, or roughly the same amount of power as 1000-typical US homes. EDIT: And now to build a thick enough cable that is weather-proofed and idiot-proof, so that no one kills themselves touching that wire... in all weather conditions (hot, cold, rain, snow, sleet), and... yeah... its actually kinda scary if you think about it.

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Yeah, in terms of "MW of fuel delivered per second", a gas station pumping gasoline is surprisingly efficient and simple. Doing it purely electrically, even at a much slower rate (30 minute charge times) is surprisingly complex.

I think most stalls are actually shared so when your neighboring stall is occupied you'll get less power. Stations are more crowded these days so it's getting common. Anyway, it doesn't actually diminish your argument, especially as 16-pod+ supercharging stations exist.

https://en.wikipedia.org/wiki/Tesla_Supercharger "When both pairs of Tesla Supercharger station stalls (A and B) are occupied, they share the available power of up to 150 kW."

Wow! 150kW. The chargers I use now are 7kW max. I wonder what kind of stress that puts on the batteries.

It's definitely harder on the batteries than regular L1/L2 charging, but it looks like maybe a low single digit difference in capacity after 50K miles, at least per https://www.energy.gov/sites/prod/files/2015/01/f19/dcfc_stu...

> I always thought it would be cool if they did in-road charging, like a slot car.

There do seem to be people working towards it, or at least giving it some serious thought [1], and there's at least one proposed pilot/experimental scheme, such as [2] in Indiana.

[1] https://news.cornell.edu/stories/2021/04/research-paves-way-...

[2] https://www.greencarreports.com/news/1132979_wireless-ev-cha...

https://www.youtube.com/watch?v=27100u7IcII like this for trucks in Sweden?

I've often wondered how effective a large induction loop would be in tapping power off of transmisison lines.

The transmission lines are designed to minimize the H-field radiation, so they're actively working against you trying to couple via the H-field.

Apparently people just do not understand how much power a car uses.

Bro you just need some solar panels on top all this charging stuff is for the birds.

I swear I’ve seen photos of an EV that was hacked that way like 5 years ago. Maybe an early model S?

It was a Prius. https://thebolditalic.com/hacked-prius-running-on-muni-power...

Fantastic! Thanks!

I am surprised there hasnt been more power-pirates in SF - like to power your home server rack...

But if the FN buses cant eat 400A all the time - Maybe start Muni-Hosting ;-)

I wonder what Muni's power bill is (and their rate)

Thank you!

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