this post was submitted on 22 Oct 2023
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micromobility - Ebikes, scooters, longboards: Whatever floats your goat, this is micromobility

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Ebikes, bicycles, scooters, skateboards, longboards, eboards, motorcycles, skates, unicycles: Whatever floats your goat, this is all things micromobility!

"Transportation using lightweight vehicles such as bicycles or scooters, especially electric ones that may be borrowed as part of a self-service rental program in which people rent vehicles for short-term use within a town or city.

micromobility is seen as a potential solution to moving people more efficiently around cities"

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[–] EdibleFriend 21 points 1 year ago (3 children)

It'll be amazing if it works but I really want to see this in action. Last time I saw anything like this in person you had to pedal like fuck to power a light bulb.

[–] [email protected] 8 points 1 year ago* (last edited 1 year ago) (2 children)

If it was really to power the fridge then it would be better to turn the compressor directly rather than with electricity?

[–] [email protected] 7 points 1 year ago

From an efficiency standpoint sure, but then a person has to be able to consistently put out the amount of power the compressor is designed for at the times the compressor needs to run. At least with a storage system the work doesn’t have to be done at the same time it needs to be used.

[–] [email protected] 2 points 1 year ago

That's an interesting thought. You could store pressure in a tank. I wonder how efficient that would be?

[–] [email protected] 4 points 1 year ago (1 children)

These sorts of things can definitely work but you can also make one at home without a ton of trouble. Basically all generators/motors are is some magnets and coiled up wire. There are kits you can use to regulate the voltage and hook them up to battery banks.

[–] [email protected] 9 points 1 year ago (1 children)

There is no way most people can easily make this at home without a ton of trouble.

[–] [email protected] 3 points 1 year ago

If.you have the idea test it at home first, instead of some artists concept. With a working modle you can see what the real issues are.

[–] [email protected] 2 points 1 year ago

I've used stuff like that in airport amdntrain stations to charge phone. I've also tried to plug my laptop in it but it was way to hard, I could not do more than 10 min for my laptop but I could probably keep it running with a bit more practice.

[–] [email protected] 10 points 1 year ago (1 children)

There's efficiency losses in order to store it, and humans don't put out a whole lot of power anyway.

[–] [email protected] 3 points 1 year ago (1 children)

Yeah. but if you're doing it anyways for exercise, might as well use the energy.

[–] Alexstarfire 6 points 1 year ago (1 children)

Ehh, not necessarily. Would you even recoup the energy and materials needed for such a bike? Would be a bit different if the energy was stored in something other than a battery.

[–] sizzler 1 points 1 year ago (1 children)

You're already going to have the exercise bike if that's what you want so now we are only recouping the generator and parts. Why do you hate progress?

[–] Alexstarfire 1 points 1 year ago* (last edited 1 year ago)

Because if you can't recoup the energy cost then it's just more waste. I'm just saying it's not straightforward.

[–] Nouveau_Burnswick 9 points 1 year ago (2 children)

This is just solar power with extra steps.

On a more serious note, if you're spinning for exercise anyways, this is a great concept. Unfortunately, the people who I know who do it, usually use their road bikes on a static converter; so I'd like to see this as a converter rather than a full rig.

[–] [email protected] 4 points 1 year ago

extra steps

lol, that's close enough to be a pun

[–] [email protected] 2 points 1 year ago

I mean, quite a few ways we generate energy are solar with extra steps.

[–] coco 7 points 1 year ago (1 children)

Remind me of that one black miror episode !

Gotta pedal to see the girl of your dream being 🤫

[–] sizzler 1 points 1 year ago

They really went with the blacked ending.

[–] [email protected] 6 points 1 year ago (2 children)

My (relatively small) refrigerator consumes around 170kWh annually.

According to another commenter further down, a pro cyclist can put out 300W continually. That works out to about 566.6 hours, or 23.6 days of continuous cycling just to power the refrigerator for a year.

I am not a pro. The last time I seriously tried to use an exercise bike, I was able to keep a steady ~110W over 45 minutes (which left me drenched in sweat and feeling jittery for quite a few hours after the fact). That works out to 1417 hours, almost exactly 2 months, which I would need to spend on the bike at my absolute limit per year to keep my refrigerator running.

And of course, none of this is taking losses in energy transmission/storage into account. In short, I don't see this catching on any time soon.

[–] [email protected] 2 points 1 year ago (1 children)

That wouldn't be your limit for long though, if you did it regularly.

[–] [email protected] 2 points 1 year ago (1 children)

Maybe, but thet would approach the pro level, which still is not acceptable for refrigerator use. Good for their health, but not useful work

[–] [email protected] 4 points 1 year ago (1 children)

Yeah I think the electricity thing is supposed to just be a bonus.

[–] [email protected] 1 points 1 year ago

Is it? Others have questioned if the total electric gain makes up for the extra costs (which an be $$ or just environmental)

[–] extant 1 points 1 year ago (1 children)

So what you're saying is I need a very tiny refrigerator.

[–] gac11 1 points 1 year ago (1 children)

Or you could hook an electric motor up to the bike to turn the pedals

[–] extant 2 points 1 year ago

Wouldn't I need to buy two more bikes and people to pedal them to power the first bike? What if I start a gym that's only focus is cardio and then resell that energy the people nearby.

[–] Usernameblankface 1 points 1 year ago (1 children)

Looks neat, and having everything fully enclosed is a good idea. If someone is already in the habit of exercising on a stationary bike (I'm not) it could be a great way to have a backup battery or create power savings

[–] [email protected] 6 points 1 year ago (2 children)

I heard about a concept like those for a gym powered by their stationary bikes, but the math just doesn’t work. A pro rider can put out about 2000 W for a short sprint, but about 300 W for an extended time. That 300 W works out to about 5¢ worth of electricity per hour of working out, or about $20 if a person averages that for an hour per day for a year. That $20/year has to be able to cover the cost of the added generator system in the bike, whatever battery/inverter system that’s storing the energy, and/or the interlock system to put that power into one’s electrical service.

It’s great if you want to power the electronics of the stationary bike, maybe with a USB port to power one’s phone/music player. Trying to offset electrical costs with human/animal labour is not going to be net positive except in very niche situations.

[–] Starbuck 2 points 1 year ago

Bingo.

I feel like these are usually put out by some kind of art or design student who hasn’t taken enough physics courses. Sure it’s easy to say “well, you’re peddling anyways so why does it matter?” But at the end of the day making this bike over some simpler bike is never going to recoup the cost or energy required.

[–] Usernameblankface 1 points 1 year ago (1 children)

Hmm. That math sounds like it would be pretty okay for charging a phone, or saving up the energy over time to use as an emergency backup - assuming you are in an area with usually reliable power and short outages.

[–] [email protected] 1 points 1 year ago (1 children)

What’s the actual benefit there though? It costs about $0.001 to charge a cell phone, or about 10 charges per penny(if you’re somewhere that has pennies). UPS, and portable battery packs are already a thing, and the cost to charge them is a heck of a lot less than the cost of adding a dynamo to an exercise bike.

Honestly, even if the argument is some niche case like being able to power some emergency system in an off-grid setup or power outage, you’re probably much better off just putting up a small scale solar system. Another way to look at it: a food calorie costs about $0.05 on average, or $43/kWh, compared to $0.15/kWh for electricity through a utility. That’s a lot of food that needs to be stored to give a person the energy to run that bike.

This kind of thing just doesn’t make sense financially or environmentally. If the idea is to promote sustainability, this has the exact opposite effect of using resources to build something that’s never going to produce as much energy as it took to build in the first place. Even if a person is going to be using a stationary bike either way, the system needed to capture and store that energy isn’t going to ever going to capture as much energy as was spent to make it.

[–] Usernameblankface 1 points 1 year ago

I don't think there is a financial, environmental, or logical reason for this thing to exist. It would come down to "it's neat" or "it motivates me" or some excuse like that. I would not advocate for people to get one, I can just see how someone would smugly refer to it as an upgrade from their Peleton.