Hacker News Board Hacker News, browsed like a classic message board
Live data from Hacker News

Tiny electric motor can produce more than 1,000 horsepower

supercarblondie.com

Post reply on HN
Print view View original

391–400 of 616 posts

Re: Tiny electric motor can produce more than 1,000 horsepower

#391

Post by pwg »

ungreased0675 wrote: post #322
ehnto wrote: post #221

Earlier quoted context omitted.

I agree with you however I believe weight and safety are in a complex relationship right now, which has nothing to do with performance and handling. Unfortunately I feel much less safe in a Fiat 500 when a significant portion of cars in the road weigh nearly 3 tonnes and perhaps can't even see me. I suspect most people are in SUVs because they're the pragmatic trade off between safety and convenience, not because the…

I wonder if larger/heavy non-commercial vehicles were taxed at a very high rate, would more people choose Fiat 500 sized cars?

In reality, any 'vehicle' which does not meet both passenger car safety and passenger car fuel economy standards [1] should only be allowed to be licensed as a "commercial" vehicle and should pay "commercial" rate (higher) taxes (and maybe even require a "commercial" stamp on one's drivers license to operate). If the states had done this when SUV's first appeared on the scene, we might not have nearly every car on the road being a hulking monster SUV today.

[1] which no SUV's nor trucks used as passenger cars, do because they are classed as 'utility vehicles' and have lower safety/fuel economy standards -- which is why the auto-makers went whole-hog on making/selling them, it got their CAFE averages down artificially.

Re: Tiny electric motor can produce more than 1,000 horsepower

#392

Post by hinkley »

catapart wrote: post #261
Aurornis wrote: post #251

Earlier quoted context omitted.

> Could lead to significant efficiency gains for EV's, because 1/4 of the motor weight means better power-to-weight ratio... a lot of things will automatically get better. EV motors are already lightweight. The electric motor in a vehicle like a Tesla Model 3 already weighs less than you do. Reducing that one component by 75% would be a weight savings equivalent to about a half of a passenger. Not a significant effic…

It drops a buck fifty per motor . That IS a game changer. It can make cars cheaper, or longer range, or faster, or any number of other designs based on what the manufacturer is looking for. But to OP's point about flight - stacking 6 Tesla motors is not an option. Stacking 6 of these YASA motors? Much less weight.

Looks like it’s about 45 kg for a Tesla and 13 kg for this one. It at twice the horsepower. So maybe 8-10kg for a down rated model. IIRC, axial motors need their diameter to retain their efficiency advantage so a down rated one would likely be lighter but close to the same external dimensions.

But that’s still a lot less rotating mass, and might make multiple motors attractive again.

Re: Tiny electric motor can produce more than 1,000 horsepower

#393

Post by fukka42 »

RajT88 wrote: post #375
eikenberry wrote: post #363

Earlier quoted context omitted.

What is the issue? I've seen people on those bikes and they look fun to ride.

I see kids blasting around at high speeds without helmets. Kids treat them like fast bikes you do not have to pedal. Wiping out on a bike at 13mph is a very different proposition to wiping out on a bike at higher speeds. I saw just a couple nights ago some kid doing what appeared to be about 40mph on an eBike. Wind in his hair, not pedaling, just blasting it. I am sure new regulations will come to speed limit them, b…

[flagged]

Re: Tiny electric motor can produce more than 1,000 horsepower

#394

Post by mattlutze »

Aurornis wrote: post #251
davedx wrote: post #6

Could lead to significant efficiency gains for EV's, because 1/4 of the motor weight means better power-to-weight ratio... a lot of things will automatically get better. YASA was founded in 2009, a spin out from Oxford University following the PhD of founder and still CTO, Dr Tim Woolmer. "Over the decades that followed both of these technologies were explored. But despite the potential for weight reduction, smaller…

> Could lead to significant efficiency gains for EV's, because 1/4 of the motor weight means better power-to-weight ratio... a lot of things will automatically get better. EV motors are already lightweight. The electric motor in a vehicle like a Tesla Model 3 already weighs less than you do. Reducing that one component by 75% would be a weight savings equivalent to about a half of a passenger. Not a significant effic…

If you're putting motors in wheels, lower weight means reducing the weight/capacity of adjacent systems.

Lighter motors for mobile robots could also be cool.

Re: Tiny electric motor can produce more than 1,000 horsepower

#395

Post by cwmoore »

huijzer wrote: post #389
Aurornis wrote: post #251

Earlier quoted context omitted.

> Could lead to significant efficiency gains for EV's, because 1/4 of the motor weight means better power-to-weight ratio... a lot of things will automatically get better. EV motors are already lightweight. The electric motor in a vehicle like a Tesla Model 3 already weighs less than you do. Reducing that one component by 75% would be a weight savings equivalent to about a half of a passenger. Not a significant effic…

Exactly. Main problem is battery energy density. Cars can drive about 20 kilometers on 1 liter of gasoline. In comparison, Tesla's 4680 cells are at about 272-296 Wh/kg and CATL's Kirin Battery at about 255 Wh/kg. A bit efficient EV often uses 200 Wh/km, so for 1 kg of battery the electric vehicle can only reach 1-2 km. An order of magnitude difference. Theoretically, batteries could go to 1000 Wh/kg some day, which…

Oranges to apples so long as electron mass is fixed and reserve currencies fluctuate.

Re: Tiny electric motor can produce more than 1,000 horsepower

#396

Post by nomel »

iwontberude wrote: post #374

Why do we even need to drive cars, why dont we all just have trailers and then an automated robot could pull it around. Decouple the drive train from the cabin.

With all the extra coupling hardware and surface area required, the reason is performance and weight. Modern cars are all about material minimization. It's easier to add a bump to the cabin and put a motor in that volume than it is to make another mini car.

I think it would only make financial sense if it were like swappable batteries: you rent it all.

Re: Tiny electric motor can produce more than 1,000 horsepower

#397

Post by fukka42 »

floo wrote: post #177
fainpul wrote: post #149

Earlier quoted context omitted.

> 59kW/kg At this point why don't we get rid of the k prefix and write 59W/g? Edit: I was half joking, but various answers mention kW being standard for motors, kg being the SI unit for mass etc. All true, but as used here in a combined unit, which means "power density" it still would make sense IMO. It's not like the "59" tells you that it's a strong motor and hence you want kW to compare it to other motors. You can…

Because kg is the fundamental unit of mass and kW is typically used for electric motors. Same reason you wouldn't use m²/s³ even though that's also technically correct.

You're thinking of grams and watts.

Kilo is an SI prefix.

Re: Tiny electric motor can produce more than 1,000 horsepower

#398

Post by cwmoore »

RajT88 wrote: post #375
eikenberry wrote: post #363

Earlier quoted context omitted.

What is the issue? I've seen people on those bikes and they look fun to ride.

I see kids blasting around at high speeds without helmets. Kids treat them like fast bikes you do not have to pedal. Wiping out on a bike at 13mph is a very different proposition to wiping out on a bike at higher speeds. I saw just a couple nights ago some kid doing what appeared to be about 40mph on an eBike. Wind in his hair, not pedaling, just blasting it. I am sure new regulations will come to speed limit them, b…

Electric bikes offer new opportunities for built-in cigarette lighters in the space. These kids...

Re: Tiny electric motor can produce more than 1,000 horsepower

#399

Post by dafelst »

fukka42 wrote: post #393
RajT88 wrote: post #375

Earlier quoted context omitted.

I see kids blasting around at high speeds without helmets. Kids treat them like fast bikes you do not have to pedal. Wiping out on a bike at 13mph is a very different proposition to wiping out on a bike at higher speeds. I saw just a couple nights ago some kid doing what appeared to be about 40mph on an eBike. Wind in his hair, not pedaling, just blasting it. I am sure new regulations will come to speed limit them, b…

[flagged]

And believe it or not, a good proportion of us are not happy about that either.

Re: Tiny electric motor can produce more than 1,000 horsepower

#400

Post by mattlutze »

huijzer wrote: post #389
Aurornis wrote: post #251

Earlier quoted context omitted.

> Could lead to significant efficiency gains for EV's, because 1/4 of the motor weight means better power-to-weight ratio... a lot of things will automatically get better. EV motors are already lightweight. The electric motor in a vehicle like a Tesla Model 3 already weighs less than you do. Reducing that one component by 75% would be a weight savings equivalent to about a half of a passenger. Not a significant effic…

Exactly. Main problem is battery energy density. Cars can drive about 20 kilometers on 1 liter of gasoline. In comparison, Tesla's 4680 cells are at about 272-296 Wh/kg and CATL's Kirin Battery at about 255 Wh/kg. A bit efficient EV often uses 200 Wh/km, so for 1 kg of battery the electric vehicle can only reach 1-2 km. An order of magnitude difference. Theoretically, batteries could go to 1000 Wh/kg some day, which…

https://ev-database.org/cheatsheet/energy-consumption-electr...

The Model 3 manages < 140 Wh/km, and many seem to be under 150/160/170.

Post reply on HN