For both short and long term? An electric chair is 24 volts the charger takes 4-6 hours to fully charge the unit. Charger has specs listed of 120 v and 3.8 amps so by my math that should be a draw of 456 watts.

Short term you have
Generator- loud, uses gas, extra bulk to haul a gen set yet it can power more than a single device
Power inverter off truck- small, easy to pack, quiet, would drain truck battery so you'd have to use gas to keep alternator running.

Long term
Solar- shorter time to generate power vs wind
Wind- higher the better-24 hours a day


How would you do it?

I have a brother that uses a power wheel chair. Generator is really the only way to do it. With solar you are going to be wanting to use it during the day. Wind isn't going to do enough during the night. You could use an inverter but you are just draining one battery to charge another (or using a vehicle's gas). Plus, sometimes the chargers don't like the power inverters put out.

Best option is to get a small honda gen IMHO.

Won't have to worry about it for long. Batteries only last a few years in that type of usage. Might be best to get them a manual wheel chair for a backup.

ETA - Get a honda generator and a 120vac -> 24vdc power supply @ 100 amps and replace the batteries with that setup :D

Some types of sealed batteries are capable of being safely recharged at very high rates - Which can greatly reduce generator run-time.

For example, some of the AGM batteries made by Concorde and Odyssey are rated for 3C recharge rates (i.e., 105 amps for a 35 AH wheelchair battery).

So, with the right battery choice and a charger upgrade, using a generator as the power source becomes a lot more practical.

3.8 amps@120v is certainly a short surge when first plugged in. Measure actual draw under use, I'll bet it's 1-2a.

If you want to charge it with solar or wind, you needed yet another battery bank.  Let your solar panels/turbine charge their own batteries all day, then (with an inverter) use those to charge the wheelchair at night, or whenever needed.  If one of these were in my plans long term, i'd probably do that.  A pair of 6v golf cart batteries in series, a hundred watts of panels, and a charge controller.  It would be quite useful for a lot of other things as well.

You *could* hack a 24v solar panel directly to the chair batteries, and let that charge them whenever they can be in the sun, but that makes you keep it outdoors a lot during the day.

Now, that's all long term and solar.  Short term, I'd use a small generator, and call it good.

How good would a waterwheel turning like a crank generator be? If you were near a steady flowing river, might be a thought?

I am completely ignorant when it comes to this stuff, I'm just spit balling.

How about a gas powered wheelchair

https://www.youtube.com/watch?v=-duZOgoTyW8

Are you able to use a conventional wheelchair in a pinch? If not it would be awesome to be able to have some batteries charging while the others are used. I suspect they aren't designed to be quickly changed.

short term, there are a number of solutions, as mentioned above.  Long term?  No real solutions at all.  Best get a good manual chair, and call it good.

But......

What is the charger inside putting out? I doubt the batteries are 120 V DC with a huge rectifier/converter inline. So find out if the batteries are wired for 12/24/36/48 VDC. Find out if SLA or AGM. Then we can find options.

Edit: I read again, 24V. Look at the Norco Genius chargers. They work great for all types, have delsulfacation, power supply mode, etc. Also a two bank charger and a extra set of batteries would be ideal. And find out what AH rating, as in amp hours. A step up in AH will yield more runtime and time between charging.

Having a manual chair needs to be an option.

Your absolute best bet for the chair isn't going to be figuring out how to just charge the onboard batteries, but figuring out how to swap the batteries.  Charging the batteries from just about any source is going to be wasteful, especially if it's from another stored power source.   Need to find an alternate system, for instance golf cart or marine batteries, that you can charge and then swap out. 4 6v batteriEs in series, or 2 12v batteries.  Ideally you are going to want to cut out your source of power loss/inefficiency, and the source of the greatest loss here is converting DC to AC and then back to DC.  So find a solar setup, and directly charge your batteries off of that.  Maybe 2 spare sets of batteries in a constant rotation, where 1 set is  always full, 1 always charging, and 1 in the chair.  As soon as the set on the charger is full, Batteries come out of the chair and go on the charger, and you swap the reserve set in.  This system would really help rationing in a shtf situation.