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Commercially Available Bike Generators Are Not Sustainable (2011)

solar.lowtechmagazine.com

21–30 of 56 posts

Re: Commercially Available Bike Generators Are Not Sustainable (2011)

#21
post #12
post #4

Needs "2011" in the title. For example the section about friction drive hasn't been true for about a decade now

Nobody would (or should, at least) be using a lead-acid battery for this in 2026, either. Full-cycle efficiency should be higher now. And the inverter. And the generator.

Huh? Was I wrong about something here? If so, please educate me.

Re: Commercially Available Bike Generators Are Not Sustainable (2011)

#22
post #19

Might have changed their attitude since then as they posted in 2022 about a DIY guide on making a bike generator: https://solar.lowtechmagazine.com/2022/03/how-to-build-a-pra...

I thought he was posting about some retro product until I saw the USB ports in the energy delivery. Weird that he edited his photos to look like that, and used retro components otherwise.

Re: Commercially Available Bike Generators Are Not Sustainable (2011)

#23
post #18

Earlier quoted context omitted.

To be fair (as a joke), it's from Low Tech Magazine. Lithium batteries are too high-tech for them. They want you to power your mechanical blender, mixer, and other machines with a drive belt. Turn the drum of your washing machine with a wood fire heating the water.

Solar panels I think are too high tech for them. I remember reading about low tech efficient cook stoves for poor countries and thinking the misses would rather have an induction burner, microwave, and an ice chest running off a solar panel.

The server the article is being hosted on is battery powered via solar. You can see it's charge percent on any page the server sends back to you.

https://solar.lowtechmagazine.com/power/

Re: Commercially Available Bike Generators Are Not Sustainable (2011)

#24
post #19

Might have changed their attitude since then as they posted in 2022 about a DIY guide on making a bike generator: https://solar.lowtechmagazine.com/2022/03/how-to-build-a-pra...

I thought he was posting about some retro product until I saw the USB ports in the energy delivery. Weird that he edited his photos to look like that, and used retro components otherwise.

The author does all sorts of odd-looking optimizations in order to make the web page run on a single host of cheap battery/solar powered compute.

It does seem a bit extreme, but the proof of the pudding is in the eating: this website has been featured on the HN front page many times and I’ve not seen it ever falter. The same cannot be said for the many run of the mill “infinite scalability” cloud based SPA’s that make the front page – even those maintained by sizable organizations with hefty cloud budgets.

Re: Commercially Available Bike Generators Are Not Sustainable (2011)

#26
post #19

Might have changed their attitude since then as they posted in 2022 about a DIY guide on making a bike generator: https://solar.lowtechmagazine.com/2022/03/how-to-build-a-pra...

I thought he was posting about some retro product until I saw the USB ports in the energy delivery. Weird that he edited his photos to look like that, and used retro components otherwise.

I think the photos look like that to achieve a very small file size. The whole site is hosted and a small solar and battery powered server, so every MB matters.

Re: Commercially Available Bike Generators Are Not Sustainable (2011)

#27
post #19

Might have changed their attitude since then as they posted in 2022 about a DIY guide on making a bike generator: https://solar.lowtechmagazine.com/2022/03/how-to-build-a-pra...

[flagged]

>Nobody is using lead-acid anymore, which shows how out of touch these idiots are with reality. For 5, if not 10 years LiFePO4 batteries have been the best option even for DIY systems

Ok, but they often are lead acid batteries. I just bought an inverter off a guy with lead acid batteries. They exist like crazy all over the place because lead acid can be reconditioned effectively forever with proper equalization. If you have lots of solar and you value repairability with simple tools and simple skills lead acid still has a niche

Re: Commercially Available Bike Generators Are Not Sustainable (2011)

#28
post #5

You could attach pedals directly to motor axle and control charging power drawn precisely to ensure smooth rotation in absence of the flywheel. It could be really small.

No, you can't. Most generators have to be spun at a thousand or several thousand RPMs to put out any sort of amount of power.

Your average inexperienced person can pedal at maybe 80rpm comfortably, but probably considers even that to be "fast."

A road cyclist with a year or so under their belt will do 100rpm if they put their mind to it and are positioned well biomechanically. Above that, to do it and be smooth and efficient, especially for any sort of sustained effort, you have to have a decent amount of experience/training.

That's well over 10x too slow.

And there's still the issue of your average person only being able to put out 100-200W past about 1-3 minutes.

Re: Commercially Available Bike Generators Are Not Sustainable (2011)

#29
post #19

Might have changed their attitude since then as they posted in 2022 about a DIY guide on making a bike generator: https://solar.lowtechmagazine.com/2022/03/how-to-build-a-pra...

[flagged]

When did lead-acid stop being cheaper than any version of lithium?

Re: Commercially Available Bike Generators Are Not Sustainable (2011)

#30
post #19

Might have changed their attitude since then as they posted in 2022 about a DIY guide on making a bike generator: https://solar.lowtechmagazine.com/2022/03/how-to-build-a-pra...

[flagged]

Were people doing much with Li in 2011? I don't remember them being all that accessible until a few years later but maybe that's just when they filtered into the worlds I was in at the time.
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