Practical and theoretic electric bus conversions...

[peteg59]

As a follow on to an earlier thread that was driven astray, I'm opening a new thread for the sole purpose of discussing the upcoming future of school bus transformation to electric power.

Here's an article on a Canadian company already producing school busses for the commercial market:
https://www.foxnews.com/tech/school-...ctric-facelift

https://thelionelectric.com/en/

Sorry I don't have any real experience in electrical engineering, but await any comments and additions to keep the discussion "alive"...

[Mark_In_MA]

I think the real question is just the batteries. Electric motors aren't new, the technology has been around for almost 130 years. The only problem is that you need a set of wires following you around to provide power. . . .




Source : Pullmans 8535, 8514 and 8537 at the North Cambridge car house on October 10, 1967

They were quiet, didn't pollute from the tailpipe (yes, there are still emissions from the power plant), and they handled pretty well. With a single electric motor,maintenance was pretty simple. Plus, there's no combustion engine - so no oil changes. If you can design regenerative braking system, that saves on brakes too. Electric heat is a no-brainer.

All of those things should still be true today, we just need to build a battery system that can power them. A school bus is a good candidate for an all-electric - you've got a known route distance, plus a safety factor, so you know how big of a battery you should need. You've also got a solid 8 hours for the bus to sit and charge all night between runs. (While it might not take 8 hours to charge an individual bus, if you need to charge a fleet of 20 buses, and you have enough power to charge 5 at a time. . .)

I think the real issue is how well the batteries hold up. How many charge-discharge cycles can they take, and how much will capacity degrade over time? The electric drivetrain works and ages decently with smaller vehicles - as hybrids with the Prius, and as all-electric with the Tesla, Bolt, etc.


Maybe it's possible that wheel-based motors will allow all-wheel-drive models in the future.

[Sehnsucht]

I agree that battery capacity-to-weight ratio is the weakest link in the all-electric equation. Until there's some unprecedented evolutionary leap forward in battery technology that can bring it to parity with fossil fuels then electric will be only moderately adaptable to meet a broad spectrum of logistics needs. This mystical battery evolution will need to be well nigh magical as well because the demand for rare earth elements is as self-defeating as the fossil fuel equation in terms of demanding energy intensive mining for a non-renewing limited resource.

[HazMatt]

Pete: Thanx for jump starting this electrifyingly exciting topic on a new thread. One that is dedicated to exploring and expounding upon the topic. Pure research and think-tanking, without the fetters of brand-bias or impracticable parameters... Well done, sir!
I believe one of the reasons many of us love our Skoolie is that it is analogous to a military APC. Comparatively over-engineered, with safety in mind, beyond that of the majority of civilian conveyances.
That strength comes with a hefty price tag attached. Weight. Lots and lots of weight.
Skoolies are simply massive! Any attempt to move all that mass from a dead stop and maintain momentum requires considerable motive power. At present EV technology levels, the weight-to-thrust ratio makes Skoolies impractical for an EV retrofit conversion.
Currently, it is still a dream to design a system that may operate for reasonably protracted distances, has an infrastructure in place for recharging, and has an acceptable useage cost/benefit lifespan.
If we remove trying to hammer the round peg of a Skoolie into the square hole of large EV feasibility from the equation, the problem becomes less insurmountable.
Lightweight construction becomes the Grail for transforming the dream into reality.
Pultruded fiber reinforced plastic (FRP) is lightweight (up to 75% lighter than steel), similar in strength horizontally, is corrosion resistant, has high impact strength, is electrically non-conductive, possesses low thermal conductivity, and, as an added benny, is EM/RF transparent.
Not only will 4G and cell signal strength be unimpeded, that last characteristic would give low-tech stealth camping a high-tech aspect...