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usrusr 24 hours ago [-]
Needs "2011" in the title. For example the section about friction drive hasn't been true for about a decade now
rgmerk 22 hours ago [-]
Not to mention they’re talking about lead-acid batteries, which have been replaced for pretty much every application, except (for now) starter motor batteries for combustion vehicles, by the various lithium batteries.
chihuahua 22 hours ago [-]
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.
Gibbon1 21 hours ago [-]
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.
rgmerk 18 hours ago [-]
I would too...but an off-grid solar and battery setup sufficient to run the induction stove and microwave is still well into four figures - cheap for a developed country resident who wants some basic comforts in their wilderness lodge, but still well out of reach for a subsistence farmer in the poorest parts of the world.
eru 18 hours ago [-]
Increasingly becoming more affordable. Especially as financing becomes easier. And you don't have to buy everything all at once.
Gibbon1 14 hours ago [-]
That's the thing, like the used to be very expensive swing compressor ice chests that you can buy in the US for $150. You'd only need a 100 amp hour battery and a 100W solar panel to power it.
eru 10 hours ago [-]
And you can probably share it between a few families, or even use it to run a small business.
getpokedagain 21 hours ago [-]
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.
> the misses would rather have an induction burner, microwave, and an ice chest running off a solar panel.
Those would definitely be hits.
Also, solar panels are old. Bell Labs demonstrated the first practical silicon solar cell in 1954. At some point, you're just trying to split (possibly nonexistent) hairs for an aesthetic, as opposed to making a principled stand against technology.
even EVs still have lead acid batteries, not all, but most
alex_young 16 hours ago [-]
"have" is doing most of the work here. Most EVs have a small 12v battery to power 12v components. But the driving the car to the store part is done with lithium.
allenrb 22 hours ago [-]
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.
allenrb 21 hours ago [-]
Huh? Was I wrong about something here? If so, please educate me.
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.
sunshinesnacks 20 hours ago [-]
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.
mrob 15 hours ago [-]
For photographic images, dithered PNGs have worse quality:size ratio than JPEGs. If you want small files and are willing to sacrifice quality you can turn the JPEG compression up or reduce the resolution.
physicalecon 21 hours ago [-]
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.
thenthenthen 12 hours ago [-]
It is an experiment, over the years various people have contributed “odd-looking” optimisations, its a great project!
IMO the only optimization they 'missed' is to pre-compress the static files and images on disk, since it's cheaper to decompress on-the-fly if the client doesn't support gzip. The could use zopfli to "extra compress" the most frequently accessed files, and use this as a solar dump load to usefully burn extra power when the batteries are full (perhaps compressing with gzip -1 when Pelican re-builds the static site, or even avoid pre-compression altogether during the build process.
> Our dashboard also includes a 220V circuit. That makes it compatible with grid-powered devices (110V in the US, 240V in the UK).
Retro-look nit: all are outdated nominal voltages. The US is 120 V (since the 1960s), while the UK and EU are 230 V (since the mid-1990s).
bityard 5 hours ago [-]
If we are picking nits, almost every panel in the US and Canada is _both_ 120v and 240v. But even electricians here commonly say "two-twenty" instead of "two-forty."
KennyBlanken 20 hours ago [-]
What do you expect from idiot hipsters incapable of basic math and science, and who generally have no idea what the hell they're talking about, just building stuff well enough to take a few pictures?
Some quotes:
"Off-grid solar PV systems often charge lead-acid batteries."
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.
You lose half the power you put into them, the deeper you discharge them the more you wear them out which means you have to buy far more capacity than you need, whereas LiFePO4 you can discharge down to 10% and charge to 90% and still get thousands of cycles out of them before they degrade to maybe 80% of their nameplate capacity. You also get higher working voltage - 13-13.8v for much of the battery's state of charge. I'm not kidding when I say that from efficiency losses alone you DOUBLE your effective solar generation by switching to LiFePO4 from lead-acid.
"At the other extreme, resistance on the pedals is too high when powering a kettle or a refrigerator."
It would take three hours for the average person to put enough energy into a "perfect" kettle to get it to boil, using a "perfect" bike that could convert the roughly 100W of mechanical effort into 100W of heat in the kettle....
Between mechanical and electrical losses, heat loss in the kettle, and energy inefficiency of the human body, I would rule it nearly impossible for even some of the world's most elite cyclists to power an electric kettle long enough for it to boil.
The handcart article goes to explain at length why a multitude of other options are inferior, but then they act like an electric generator bike would provide any sort of meaningful amount of power compared to just putting a solar panel outside.
Especially if you're willing to buy used, solar is dirt cheap. You can get NEW panels 300-400W panels on clearance for ~$100. You can get a nice-but-cheap 1-1.3kWh 12v battery for about $250. A top-notch solar controller, $75-100. And that battery will fully charge from dead in one day worth of sun in non-ideal conditions...
dendrite9 20 hours ago [-]
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.
pocksuppet 20 hours ago [-]
When did lead-acid stop being cheaper than any version of lithium?
stephen_g 18 hours ago [-]
Pretty recently, maybe in the last year or so?. It's pretty crazy to see it - CATL have started selling LiFePO4 cells as low as US$63/kWh while lead acid tends to cost more than US$100 per kWh! Obviously a finished battery + retail margin is going to cost more than those figures but we're coming to the point where it will just be cheaper than lead acid on an amp-hour to amp-hour basis.
Of course, on a Total Cost of Ownership (TCO) basis, it was already cheaper quite a while ago (for the last 5 years I'd guess). It was a combination of LiFePO4 batteries having such longer cycle lives than any lead-acid chemistry, and the greater depth of discharge meaning you could use a lot more of the energy. So if you build a new lead-acid based system, you'd need almost double the amp-hours of batteries to supply the same amount of energy with a safe depth of discharge, and you'd still have to replace them much sooner. So you'd not only have to factor buying a lot more batteries with lead acid but also replacing all the lead acid batteries at least once while a LiFePO4 system would continue to operate.
emj 16 hours ago [-]
Lead acid is cheaper because they are really easy to recycle so in a low tech env they are preferable.
stephen_g 11 hours ago [-]
I don’t know about that - yes it’s simpler to recycle but the cycle life is at least four times longer (I had accidentally understated in my post, did some more reading and lead acid is worse than I remembered), but apparently advanced LiFePO4 cells are getting potentially more like eight or nine times the cycle count!
So if you think about the amount of materials - lead acid are almost double the weight vs. lithium batteries per amp hour to start with, then multiply by two because of the usable capacity difference, times four to eight for the cycle life… So you’re talking having to recycle something like sixteen to thirty-two times the weight of the lithium batteries in lead, before the LiFePO4 batteries would have even reached their end of life!
It’s really almost unbelievable how much better and cheaper the lithium batteries have become!
idiotsecant 20 hours ago [-]
>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
rgmerk 22 hours ago [-]
This arguably had some relevance in 2011. In 2026, cheap solar and batteries make human-powered static devices that would benefit from the extra power of a stationary cyclist completely redundant.
tocs3 5 days ago [-]
Some things I would like to see are pedal controlled devices. Something like a pedal controlled wheelchair, not powered by the pedals just control the forward and back motion. My mother with sever arthritis can still pedal but has a very hard time walking. It would be a little exercise doing something that needs to be done (getting around). A pedal controlled remote control lawnmower would be nifty also.
Where I used to live an elderly gent rode a very low to ground bike. Looked a lot like the silly motorbikes some peeps do. I imagine they’re out there for sale.
Tanoc 22 hours ago [-]
A recumbent bicycle perhaps? Often has pedals ahead of the front wheel, where you lay down in a hammock or moulded seat?
analog31 21 hours ago [-]
Yes, there are electric recumbent trikes out there, such as the Tadpole. A friend of mine got one after he recovered from a stroke and could no longer balance on a conventional bike. He rode it to work. It got him outdoors, with "anything is better than nothing" level of exercise.
grebc 21 hours ago [-]
That's it!
Sorry I lacked the proper name, but yes they are about. And definitely look like they could help people certain health issues. Although getting down into it would be something to consider for older peeps.
Walf 18 hours ago [-]
Have you seen what people are doing with hoverboards + wheelchairs? Carer- & user-operated variations. Not professional solutions, but certainly fill a need.
micromacrofoot 22 hours ago [-]
many ebikes work this way, pedaling and the chain more or less signal the motor rather than provide meaningful power... though afaik none of them do backwards for obvious reasons
she might enjoy an etrike, though more for recreation than normal day to day
fergie 16 hours ago [-]
I'm suprised that the author didn't consider dynohubs which were also a thing in back in 2011, and are getting slightly better all the time.
lostlogin 16 hours ago [-]
> dynohub
Thanks, I learned something. I’m suprised how little drag they seem to add.
Are there options that don't limit the output power? Typically the light power is limited, so dynamos only provide around 5 W or so, which already makes them not so attractive even for charging your phone on a bike.
Zambyte 10 hours ago [-]
I think the problem with having a higher wattage is that you can't have a substantial amount without introducing what would generally be an undesirable amount of drag. It would certainly be useful to be able to engage / disengage a dynamo hub at a higher wattage though.
Mugshelf 22 hours ago [-]
Tried one at a demo; you put in a ton of work for minimal wattage. Much better off with a decent power bank, honestly.
scotty79 23 hours ago [-]
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.
KennyBlanken 20 hours ago [-]
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.
16 hours ago [-]
scotty79 17 hours ago [-]
You can have a motor with planetary gearbox built in.
mmooss 18 hours ago [-]
> An energy loss of 42 to 67.5 percent of naturally means that it takes 42 to 67.5 percent more effort or time to power a device (say, a blender) via electricity compared to powering the same device mechanically.
Nope. If input is 100W, loss is 60%, and resulting in output of 40W, then to increase output to 100W you don't need 60% more input (which would output 64W) you need 150% more input.
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.
https://solar.lowtechmagazine.com/power/
Those would definitely be hits.
Also, solar panels are old. Bell Labs demonstrated the first practical silicon solar cell in 1954. At some point, you're just trying to split (possibly nonexistent) hairs for an aesthetic, as opposed to making a principled stand against technology.
https://www.aps.org/apsnews/2009/04/bell-labs-silicon-solar-...
Full-cycle efficiency should be higher now. And the inverter. And the generator.
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.
https://solar.lowtechmagazine.com/about/the-solar-website/#h...
https://github.com/lowtechmag/solar/wiki/Solar-Web-Design
https://homebrewserver.club/low-tech-website-howto.html
IMO the only optimization they 'missed' is to pre-compress the static files and images on disk, since it's cheaper to decompress on-the-fly if the client doesn't support gzip. The could use zopfli to "extra compress" the most frequently accessed files, and use this as a solar dump load to usefully burn extra power when the batteries are full (perhaps compressing with gzip -1 when Pelican re-builds the static site, or even avoid pre-compression altogether during the build process.
https://blog.llandsmeer.com/tech/2019/08/29/precompression.h...
https://github.com/google/zopfli
https://github.com/kurtmckee/pelican-precompress
Retro-look nit: all are outdated nominal voltages. The US is 120 V (since the 1960s), while the UK and EU are 230 V (since the mid-1990s).
Some quotes:
"Off-grid solar PV systems often charge lead-acid batteries."
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.
You lose half the power you put into them, the deeper you discharge them the more you wear them out which means you have to buy far more capacity than you need, whereas LiFePO4 you can discharge down to 10% and charge to 90% and still get thousands of cycles out of them before they degrade to maybe 80% of their nameplate capacity. You also get higher working voltage - 13-13.8v for much of the battery's state of charge. I'm not kidding when I say that from efficiency losses alone you DOUBLE your effective solar generation by switching to LiFePO4 from lead-acid.
"At the other extreme, resistance on the pedals is too high when powering a kettle or a refrigerator."
It would take three hours for the average person to put enough energy into a "perfect" kettle to get it to boil, using a "perfect" bike that could convert the roughly 100W of mechanical effort into 100W of heat in the kettle....
Between mechanical and electrical losses, heat loss in the kettle, and energy inefficiency of the human body, I would rule it nearly impossible for even some of the world's most elite cyclists to power an electric kettle long enough for it to boil.
The handcart article goes to explain at length why a multitude of other options are inferior, but then they act like an electric generator bike would provide any sort of meaningful amount of power compared to just putting a solar panel outside.
Especially if you're willing to buy used, solar is dirt cheap. You can get NEW panels 300-400W panels on clearance for ~$100. You can get a nice-but-cheap 1-1.3kWh 12v battery for about $250. A top-notch solar controller, $75-100. And that battery will fully charge from dead in one day worth of sun in non-ideal conditions...
Of course, on a Total Cost of Ownership (TCO) basis, it was already cheaper quite a while ago (for the last 5 years I'd guess). It was a combination of LiFePO4 batteries having such longer cycle lives than any lead-acid chemistry, and the greater depth of discharge meaning you could use a lot more of the energy. So if you build a new lead-acid based system, you'd need almost double the amp-hours of batteries to supply the same amount of energy with a safe depth of discharge, and you'd still have to replace them much sooner. So you'd not only have to factor buying a lot more batteries with lead acid but also replacing all the lead acid batteries at least once while a LiFePO4 system would continue to operate.
So if you think about the amount of materials - lead acid are almost double the weight vs. lithium batteries per amp hour to start with, then multiply by two because of the usable capacity difference, times four to eight for the cycle life… So you’re talking having to recycle something like sixteen to thirty-two times the weight of the lithium batteries in lead, before the LiFePO4 batteries would have even reached their end of life!
It’s really almost unbelievable how much better and cheaper the lithium batteries have become!
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
Sorry I lacked the proper name, but yes they are about. And definitely look like they could help people certain health issues. Although getting down into it would be something to consider for older peeps.
she might enjoy an etrike, though more for recreation than normal day to day
Thanks, I learned something. I’m suprised how little drag they seem to add.
https://www.cyclingabout.com/dynamo-hub-power-drag-testing-s...
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.
Nope. If input is 100W, loss is 60%, and resulting in output of 40W, then to increase output to 100W you don't need 60% more input (which would output 64W) you need 150% more input.