Pedal powered farms and factories: forgotten future of stationary bicycle (2011)
lowtechmagazine.com
lowtechmagazine.com
It's like we all have our own army of personal slaves by the thousands that run on ancient sun light to power our excessive needs..
I might not be able to power a kettle, keep the fridge on and all those things that take 10-20 x 1hup but, most of the time I don't need those things.
What I would like on the bicycle is a general purpose recharegeable battery that works off a dynamo and powers the lights on the bike. If it can charge for free on re-gen braking and give a feeble power assist if need be then that would be helpful. But not something actually heavy.
The problem with batteries is they always come in boxes that need other containers that need housings and brackets and even more mounting hardware.
I would like a battery to be practically structural, so, in the bicycle implementation the battery would use the frame tubes, to be more like an internal layer of paint than something big and heavy.
Anyway, it would be great if a bicycle could harvest electricity and store it in a way the EV cars are talking about, but to return electricity to one's personal grid of USB powered devices so, even if you did not have mains power you could always get everything charged.
An alternator gets surprisingly hard to turn when it actually has a full load connected to it. I'd compare it to biking uphill.
Still useful for getting a laptop and two smartphones fully charged when you exercise, though.
I think 150W for an hour would be more reasonable for a typical person, even then you're going to get pretty sweaty.
There's a pair of issues with that plan:
* 75w is mechanical, factor in the converter and you end up with quite a bit less.
* 75w is what you can produce doing nothing else, you're not really able to use that computer while you're doing that. It's not strenuous exercise, but it's continuous work.
> I might not be able to power a kettle, keep the fridge on and all those things that take 10-20 x 1hup but, most of the time I don't need those things.
OTOH you can't really need a fridge only some of the time. At that point you're better off with some sort of evaporating cooler or (dry-)ice box.
> What I would like on the bicycle is a general purpose recharegeable battery that works off a dynamo and powers the lights on the bike.
… buy one? Get a dynamo-charged buffer battery and plug a USB headlight in it or whatever.
> I would like a battery to be practically structural, so, in the bicycle implementation the battery would use the frame tubes, to be more like an internal layer of paint than something big and heavy.
A battery is big and heavy by definition. And will remain thus until we get an absolute breakthrough.
> to be more like an internal layer of paint than something big and heavy.
Magic, got it.
Even more so if you factor in the entire human biological system. Humans are pretty shit at converting food to mechanical energy, to say nothing of considering the entire chain from sunlight on. And our average power output is nothing worth speaking about either.
A pedal-powered work bench of some sort (where the pedalling is an ancillary activity to the primary work e.g. pottery wheel or loom or whatever) can make sense, the mechanical energy requirement are limited and most of the work is relevant to human skills. But for primary power production it makes limited sense, at least in developed countries.
> Just stick a solar panel array on your factory and be done with it.
For factories sure but there is a huge advantage to pedal-powered prime movers: they're very easy to slap together and maintain. Solar panels are not always easy to have in low-infrastructure / developing country environments, slapping belts and rods onto a bicycle frame is much more accessible.
1. The tendency to have electric appliances for every thinkable mundane task does our bodies no good (nor the environment). While we can go to the gym once in a while to alleviate some of the ill effects, it is much better to incorporate some physical exercise into our daily routines.
2. To be totally dependent on a centralized grid is a recipe for disaster. Many million can be put at risk by a single hacker in a basement as it stands, not to mention when state actors are involved. Electricity should really be supplied by local semi-independent grids fed by local renewable energy sources that are resilient to a collapse of the centralized system. Pedal power could play one (minor) part in such resiliency.
And they're pretty good at scaling human activity since they can route/draw power from other places.
About pedal power, it's nice to look for alternatives but if there's one thing I learned, convenience trumps everything else. We literally die for convenience (drugs, alcohol, being overweight, not exercising, etc.).
It's less "minor" and more "insignificant". A healthy and motivated laborer can sustain ~75W mechanical over a continuous work day, that's an entry mat worth of solar cells, or a small turbine / windmill.
You can derive some productivity from your exercise, but humans as power source is inane unless you have literally no infrastructure worth speaking of and no other options (e.g. no wind or water streams).
But, unfortunately, some quick sums suggest this might not be particularly economically viable:
- 75W sustainable energy output per person, i.e. 0.075kWh
- 33% efficiency of energy conversion, i.e. 0.025kWh
- GBP0.05 per kWh to sell back to grid, i.e. GBP0.00125 per person per hour
- 8 hour day = GBP0.01 (i.e. 1p) per person per day
- 100 people in a gym, or prison, or whatever = GBP1 per group per day
i.e. unlikely to cover the cost of lighting and heating. Even if you could improve to 100% efficiency, and offset against electricity purchased rather than reselling back to the grid, you'd still only be looking at increasing that by a factor of 10.
You forgot the most important factor in this - extra food.
Those people will burn a lot of calories, and surely enough compensate for it with a snack or maybe an extra meal. That alone makes any sort of human electricity generation scheme generally not viable.
It didn't do too well.
https://www.gardeners.com/buy/extra-large-compost-tumbler/36...
These are easy enough to hand crank and you don't need to tumble them a great deal each time.
Maybe if you had a hobby farm and many such tumblers, adding some sort of pedal drive you could temporarily attach to each tumbler might make sense.
Only half joking, because bulls and donkeys were used to power a lot of machinery and still are, and even dogs were used on hamster wheels to power rotisseries (their depictions were sad, indeed).
But I would like, and have thought about, a treadmill or stationary bike to exercise and recharge a power bank or two, for example. It wouldn't be much, but it's not hard to implement and I'd rather have several smartphone charges than just excess motion/heat.
On that note, it would probably be more efficient to grow crops, distill alcohol, quit drinking and use that to power a generator... That or compost it to gas, biofuel :D
I’d prefer to take my renewable energy with no quality of living sacrifice, thanks.
I'm fortunate enough to be able to afford to pay twice as much for the electricity we consume and not have to sacrifice anything. I'd guess, based on your comment, you are on the same, privileged, boat. Others are not so lucky, which means that they will need some sort of help, which might not be politically palatable because, mainly shortsightedness.
Removing fossil fuel subsidies and setting up meaningful carbon taxes are steps in the right direction, but this means that the price the consumer pays will, ultimately, be higher, which is the point I was trying to make.
FWIW, it's something that I strongly believe we should be doing but through a combination of circumstances will only very slowly happen.