I've been watching the Long Way Up motorcycle travelogue series with Ewan McGregor and Charlie Borman on AppleTV+.
They're doing the trip from the tip of South America all the way to Los Angeles on a pair of prototype electric Harley Davidsons. The support crew is in a pair of prototype Rivian pickup trucks.
The Rivians have a "tow to recharge" mode that they've used several times already in the first half dozen episodes.
The show is great and I'm as fascinated by their dedication to do the trip on electric bikes (the first parts of the trip were in freezing and sub-freezing temps in areas with long distances between grid electricity availability) as I am by the scenery and their narration.
Anyway, sorry for the tangent, but the title reminded me of the series. I hope it escapes AppleTV+ so that non-Apple folks can watch it at some point.
I've actually considered this many times, but the math never works out. I ride 50KM 3 times a week, Strava's "estimated power rating" is all over the place, given i ride the same trail every time i would think it should not be like this.
Lets be reasonable and say 160W (somewhere between all the ratings strava gave) avg for my 2 hour trip.
I think I am a pretty strong rider, at the peak of the season I can beat electric bikes on flat ground as my top speed is higher then theirs (I dont have a speed limiter, they do)
I can tell you this is NOT easy and once you realize how much physical effort it is you appreciate being able to plug things into the wall.
it is the sustained power output that will kill you.. You can probably dump 10w of power for a long time, but putting out serious power for extended periods of time isnt easy.
The math never works out, by a long stretch. Electricity is just too cheap and humans too weak.
“One kWh” sounds like a tiny amount, but it is 3,600,000 joules. If you want to store that as potential energy, you must (taking g=10m/s²) lift a mass of 360,000 kilograms by a meter.
Another way to see how large a kWh is: a human body, ballpark, needs 3kWh per day (125W an hour)
⇒ If you want to produce 3kWh a day, you’d have to eat twice what you normally eat.
And that, even ignoring heating and airconditioning, doesn’t power an average household in the western world.
I actually built a bicycle generator (an AC motor with a belt around the rear wheel) and would sell organic smoothies at music festivals. The fun part was the buyer had to pedal the bike to generate the electricty to power the blender to make the smoothie.
Even with only a 150w blender, fit adults had to work HARD to get the smoothie.. well.. smooth.
Kids basically couldn't do it, or not well enough.
A lot more efficient. This sounds like a novelty, but in reality, bicycles are for endurance more than sprint. Using a battery as a buffer would enable a customer to pedal until the battery is charged enough to blend a smoothy. That could be a slow 20 minutes cycle out a 5 minutes sprint.
A lot. In fact most "pedal smoothie machines" you see work that way.
But I wanted to build it the way I did to be educational as well. When kids struggle after 15 seconds I say "You'd have to pedal a LOT harder continuously to power your xbox. That really gets them thinking.
There was a video of an Olympic cyclist powering a toaster with a bike. He wan't able to keep it up enough to toast one piece properly.
I was super in to cycling a while ago and I was only able to average 200w over an hour but thats not quite accurate because I was going super hard and then taking rests every 20mins which stops the clock.
That’s a bad demo, as toast takes high power for a very short time.
Just about any human in decent health could probably cycle long enough (with effort) to charge a battery to provide the requisite energy (over the course of, say, 30 minutes) and then output that energy at high power to toast over 3-4 minutes.
As someone that bikes with a power meter, looking at my power curve for some rides: I've held 300W avg for 20 minutes, 200W avg for 3 hours and 160W avg for 9 hours. These are from races, a steady state effort could probably be a bit higher.
I think that may be some usable numbers for what an avid amateur cyclist can achieve (ftp ~4Ws/kg). And then one will have to take into account that the body efficiency of cycling is about 25%, so one will have to eat 4x that amount in calories...
Indeed. To put some numbers to this, here's an account of a 90 km ride I did several years ago:
I was roped into a team entry for a Half Ironman. Despite being more of a runner, I did the 90 km bike leg which was effectively a solo "time trial" (no drafting allowed) on a standard road bike with clip on aerobars. After averaging 35.0 km/h on the mostly flat (~600m elevation gain) course, I was exhausted. The SRM Powermeter I borrowed for the race said I had averaged a "measly" 215 W!
I haven't done the maths but I have a feeling the jellys you need to eat to sustain that power output marginally cost more than the electricity you would consume otherwise.
Sure, a battery does that. You could charge a battery slowly with 60 W for an hour and then discharge it quickly, powering a 1000 W device... but it would run out in a couple minutes.
e.g. USB phone charger rated for 5V/2A = 10W, laptop adapter for 19V/65A = 1.2kW, electric heater rated 110V/15A = 1650W
Voltage and current are like height and width of a 2D box named wattage or energy, and you can stretch or shrink the height thus changing width, but not the total area
yea, mobile devices are limited by the ammount of thermal energy they can dissipate. most laptop cooling systems top out at around 30W, anything more is peak load or charging.
When rowing I can throw down a significantly larger amount of power than when I'm cycling (almost a kilowatt in a short sprint), but ultimately my average sustainable power in both sports is about between 150w-250w. This article got me thinking about calculating the amount of LED bulbs someone could power given a certain V02 Max... hmm.
Very interesting to know roughly how much energy one can create doing this! Being part of the current trend of people riding at home on Wahoo Kickrs/Zwift and other turbo trainers, I do feel like that energy could be put to use somehow! Even if it were just to power a fan to cool myself down whilst riding, it would be nice to think the energy was being put to good use!
I think once you do the math, and realize how incredibly little power a human can generate compared to modern electricity, you realize it's not really worth it. Literally forgetting to turn the light off in your bathroom twice a month would probably waste more power than a super-committed, hour-every-day stationary-bike-using person would generate.
I don't mind these kinds of "solutions", but I do object when they go in the "make me feel guiltless about everything else I do because I hooked my bike up to a generator" bucket.
You’re correct on the side of power generation, it’s a tiny amount. On the other side, we have come a long long way when it comes to efficiently using power. The combined power usage of my bathrooms lights is probably less than 60W. The largest MacBook uses less than a moderately trained human can produce. On average, fridges need paltry amounts, compared to what they needed a decade ago.
Certainly, running a vacuum or boiling water won’t work with human power generation, but if you want that as a backup, you probably can fall back to a broom and use a gas/multifuel cooker in the meantime.
> Literally forgetting to turn the light off in your bathroom twice a month
8h * 5W * 2 = 80Wh per month
(Unless you're talking about using incandescent light bulbs, which would be like using a 4mpg vehicle in a discussion about average vehicle efficiency. Personally I think a 3W LED is better than a 5W, but I know most people disagree.)
Our main bathroom light draws, I'd guess, 0.1W. It shows up as 0.0 with a kill-a-watt so I don't really know. And it's only used for about half an hour a day at most.
> a super-committed, hour-every-day stationary-bike-using person
60W * 1 * 30 = 1800Wh per month
So no, forgetting to turn a light bulb off for an entire night, twice a month, does not waste more electricity than that gained by a cyclist who is capturing their electricity.
I think it's a great hack to turn this machine into an electrical generator.
Come on, this is "missing the forest for the trees" pedantics. I think you will find that the average bathroom in the US uses way above 5W.
Regardless, it's just an example. The DoE says the average US residential customer uses 909 kilowatt hours per month. Using your math of a committed cyclist that generates 1.8 kwh per month, you're still looking at under .2% of energy replacement. Which, again, even the smallest efficiency improvements in a house would completely dwarf what a human could produce.
I can only respond to your words. If you don't like my choice of bulb, then do your own math and show it like I did. See what watt bulb (not bulbs plural, or moving the goalposts even further, an entire bathroom) it takes for your assertion to be true. Actually I'll just do that myself because it's easy.
Now, we already discussed generating 1800Wh per month using this bike. So:
1800 / (8 * 2) = 112.5
Or in other words:
112.5W * 8h * 2 = 1800Wh
So you'd need to run a 112.5W light bulb for 8 hours per night, twice per month, just to equal the amount of electricity produced by the article author. Although you said that leaving the light on wasted more, so, let's just go with a 113W bulb. I'm old enough to remember 100W incandescent light bulbs, but even then, they were rarely bought and used because that's an insane amount of electricity for indoor lighting.
Now where I live I can't even buy incandescent bulbs because they're not for sale. For 112.5W to be average, there would need to be millions of Americans using stadium lighting just to take a shit.
I think you should take a step back and reflect on why you're so quick to attack someone for doing a cool hack (this is Hacker News) that reduces their electrical usage (in the time of climate change).
1800 watt-hours, or 1.8 kilowatt-hours, is 20 cents worth of electricity. Using a cycle to power things makes for a neat demo, and might be good for educating people about electricity and suchlike, but anyone who expects to notice it on their energy bill or carbon footprint, or even for the installation to pay for itself, is off by a few orders of magnitude.
Yeah, the thing is, the by far best use for "bike power" is actual transportation. 0.15kWh of pedaling power can get you surprisingly far (one hour of moderate effort cycling), but would be rather unimpressive for the usual electrical applications. Apparently, almost two centuries of doing that have lead us to some very clever and pragmatic efficiency tweaks, probably because the effort-motion feedback loop is so extremely compelling to the human mind (evolution has made us brains on an endurance locomotion machine, everything else is rather unimpressive compared to peer mammals).
Not to mention bicycles are designed for converting rotary motion into, well still rotary motion, but forwards travel; not electrical potential.
I haven't done any research or taken measurements, but particularly the low-end style tyre-on-roller that I have must be awfully inefficient.
It's been briefly popular (to some extent) a couple of times to power a light while cycling. These things don't typically have large capacitors or batteries to store surplus charge, because powering the light is about all you can do! (Ok not totally fair since you're also cycling, but still.)
The author of the article is using the bike as a back up to his solar panels when the power is out. He isn't going to be running AC and arc welders off the power generated from his bike. More likely some lights and phone/laptop charging.
The power from the bike is likely to be more than sufficient for those use cases.
I really think room lights are approaching 5W/bulb. I have a 3x5w bulb setup and keep 2 unscrewed just because it’s too bright when I have to go in at night.
Incandescents are a hard sell when LED bulbs are $1-$2 and pretty reliable.
Question - where did you get 5W from? a LED nightlight?
More realistic, a washroom is using 60W MINIMUM.. most have those light bars above the mirror and they are closer to 300W.
I recently replaced my Halogen lights with LED and cut the kithen lights from 600W to ~60W. Substantial savings, but how many people replaced everything with LEDs?
Color reproduction sucks in LED though. So if they do more than brushing teeth with bathroom mirrors they could be still rocking good old incandescent.
People that apply cosmetics need proper color representation. There’s even dedicated mirrors with built-in lights for that.
However, on average, that will not be a primary driver of energy usage in the average since most people don’t spend a substantial chunk of their time painting their face.
I am very sensitive to color temperature at night, and it really affects my sleep. E.g. Night Shift on OSX isn't enough for me so I still have the reddest possible setting for f.lux set on my computer.
I hate the light that LED bulbs give when I'm getting ready for bed. Thus, I have LEDs in most places in my house except for my bathroom and bedroom where I have incandescents.
Just as a quick example: Bringing a pot with 1 litre of regular room temperature water to boiling temperature takes about 0.1 kWh. A regular person produces about 100W during strenuous but still aerobic exercise so you'd need about an hour of cycling to generate enough energy. This doesn't include heating the pot itself btw.
Not disagreeing, but just wanted to point out that if the goal was to generate heat then humans could potentially be more efficient because of internal efficiency. The ballpark number I often see is 25% efficiency, so if you were able to somehow capture the waste heat they'd be able to heat up the water 3x as fast.
This would probably work better when heating up rooms rather than water. The benefit of using electricity as an intermediate form of power is that it becomes possible to heat water up to boiling temperature. Exercising humans never reach boiling temperature no matter how hard they try.
Fair point, though that is arguably the only situation involving electricity (besides heating the room itself which doesn't involve heat capture) in which you're actually trying to generate heat.
A single square meter solar panel which costs on the order of $100 will outproduce a human. If you're camping or in a power outage and want to charge your phone or some led lights, sure, a bike charger makes sense, but you'll never be net positive with the energy you create vs. the energy needed to produce the generator.
Solar panels only outperform a human when the sun is shining. From the article:
"But what if skies remained gray for many days in a row? Rather than trying to purchase enough battery storage to cover all reasonable eventualities, I decided that my backup source of electricity needed a backup itself, one that I could use to charge that battery during times when my photovoltaic panels won’t function"
As a primary source of energy a cycle generator doesn't make a lot of sense. But as an on demand source to cover occasional periods of low solar generation it's a great hack.
Not only that, but human power is incredibly inefficient, especially if the food you are converting into that power is not plant-based. It's significantly better if you eat plant-based, but nowhere near a bunch of solar panels covering the same area that the plants did.
Even though it won't run your refrigerator, I would have been pleased to be able to plug an external mobile device battery into a smart trainer during a recent power outage so i could continue to work on a book manuscript while power was out.
There might be a handful of time trialists here in the UK with day jobs that could do that, but yeah no one is doing that without dedicating a huge part of their life to training.
Apparently the original story had the AI use the network of human brains as a giant neural network.
As the story goes, the movie executives thought this would be too difficult for most people to understand, so they switched it out and used the thermodynamically unviable power source motive instead.
I wish The Matrix had humans in virtual reality cages because the AI had a mandate to keep them alive and well, and this was simply the most efficient mechanism for doing this. This would have made the resistance far more ambiguous as they would actually be fighting for freedom but against the well-being of humanity.
>I wish The Matrix had humans in virtual reality cages because the AI had a mandate to keep them alive and well
Humans have finite lifespans, right? So all the AI has to do "relieve" itself of the burden of keeping humans alive would be to not let them reproduce. This would be pretty easy considering that it's pretty hard for people to spontaneously become pregnant while hooked up to those pods.
It's even crazier if you start comparing the energy used for training massive AI models vs. the paltry wattage required to keep a human brain operating.
> What I really don’t relish, though, is losing Internet access
In my experience with Comcast Business Internet, their upstream equipment goes offline a few minutes after a power outage. So regardless of how you're powering your own equipment, it's hopeless.
The cell network appears to persist through power outages, but bandwidth, packet loss, and jitter aren't ideal in the best of circumstances. When it's the only Internet access for the whole neighborhood, you should probably just give up on your videochat meetings...
A little while ago we had a state wide power outage and after a few hours even the cell towers were gone (there may have been some reserve for emergency calls on other networks). I can't remember if it was this incident or another one short after that left me without power for 3 days in a first world country that wasn't hit with a large natural disaster. After this the local government quickly made changes so these days it isn't so bad. One of the improvements is a massive battery backup system owned by Tesla which is able to smooth power supply when there are unexpected spikes in demand or a power station goes offline.
Its kind of weird sitting in the dark with absolutely no communication ability.
That's really interesting. It seems like in my area their system stays up and running but that's probably because lots of people have their home phone service running through Comcast.
Rowing machines are in my experience much more efficient. 200W is maintainable for an hour or more with some experience. (2 minute split, for any rowers out there). 60W (3:00/500m) is genuinely difficult to pull - any effort at all will exceed that.
Moderately well trained (based on 8-10hr/wk cycling specific training year round) older (40+) cyclist here... 260w average for an hour is pretty reasonable... 300w for an hour for hard a effort is possible for me when measured at the crank with a power meter.
One thing to keep in mind about power numbers vs pro cyclists is that they can churn out these kinds of watts at significantly lower body weights than a recreational cyclist. For output into electricity though it doesn't matter if I’m 35lbs heavier than a pro because watts are watts.
Regardless it seems to me that these levels of output using a full body motion of a rowing machine would be exceedingly difficult for a one hour period compared to cycling that leaves most of your muscle groups relaxed.
The past paragraph is funny to me - in my experience the same wattage is much easier on a rowing machine exactly because it uses more muscles. Sure I’m primarily using my legs, but they get a slight rest each cycle when I’m at the tail end of the stroke and using arms/back.
For 1 hour FTP in heavy trading training, I did about 250 watts rowing and 300 watts cycling. I did 250 watts on the bike for about 6 hours, and I don’t think I could have done 200 watts for 3 hours rowing for several reasons.
I think the best multi-hour total energy yield efforts are from recumbent bicycles.
For a 160lb rider, that’s only somewhere in the range of 14mph sustained on flat ground. That is incredibly low for a regular cyclist. Frankly, that power is just far lower than what most people can put out. My assumption here is that Strava has very poor estimation for riders without power meters. Or your route has many stoplights and stop signs, which is difficult to account for when calculating average power.
Regular recreational cyclists can generally put out 200-250W for well over an hour depending on weight.
The question here is how hard do you ride (given by the heart rate). Do you ride at 120bpm or 160bpm? If it's 120bpm, you can probably increase the output with little training or just by accepting a higher heart rate. If it's 160bpm, something seems wrong.
how do you want strava estimates to be reliable? they can't take wind into account they can't take the efficiency of your bike, they can't take your shape (which influence the air resistance) into account that can't be reliable at all. 89w is nothing
That seems odd to me - sure in the water rowing is slower (friction is way higher), but in terms of muscle use and energy output, rowing uses way more muscles and gets better range of motion in the legs.
I think it's that the cycling movement is just more efficient for sustained efforts, possibly because it uses less muscles. For sustained efforts, I don't think being able to use more muscles is an advantage, since you're going to be limited by your cardiovascular system. If you created a bike that you could also generate power with your arms, i woudln't expect to be able to put out more power because muscles are the limiter.
The muscle fiber distribution might be in favor of only using your legs as well (eg. fast vs slow twitch)
I'm not much of a rower, but after your pull, pulling your body forward for the next row is all wasted effort as far as producing mechanical work. Cycling doesn't really have any wasted phase like this.
What I'm not sure is if you were to measure total energy expenditure at the human (as opposed to the spinning wheel), then cycling/rowing might be closer.
The reported 1 hour power seem to be on a low side. Average untrained male should not have much troubles generating 100W. Reasonably fit male that cycles regularly should be able to put about 200W. For longer intervals the power will of course decrease.
Still of course the power is low comparatively to traditional sources.
Is there a good way to put a generator on the bike itself? To say charge a powerbank/phone? I have a crappy bike (no gears, tons of rust) and I have a bad habit of going as fast as it lets me good. However I honestly don't really want to go faster than 15mph or so b/c it's generally unsafe. The problem is I have some mental block of making myself go slower. I guess I enjoy the workout. So I want to put in a resistance in somehow that I can crank up to make myself go slower. Does anyone have an ideas?
The generators I've found online seem kinda whimpy and just slide on the exterior of the tire/rim. Is there is something more hardcore I can put on the chain or something?
I wonder how much more efficient the generation could be? 60Watts is still somewhat impressive in the rig mentioned, but I wonder if maybe better control of the rpms of the generator (through gearing) could give more efficient generation. I feel like at the gym, the workout bikes (which I think are generally powered by pedaling), will give you a wattage output that seemed higher than than 60 watts, but again, that's about resistance (and not taking into account the inefficiencies of power generation). Seems like it could be made usable for a daily power generation machine (reminds me of "Oxygen Not Included", where you have the person run on a hamster wheel to generate power).
Pro cyclists can sustain 300W for an hour or more, and even trained amateurs can break 200W pretty happily, so 60W sounds like a lot is being left on the table, yes.
The hour record is held by Bradley Wiggins, and it's estimated he averaged 440 watts.
For comparison, I'm reasonably trained, and could maybe hold that for 4 minutes. I'm also considerably heavier!
I would guess that a random average adult male who doesn't neglect general fitness, but doesn't necessarily cycle, could put out 160w-220w for an hour if they were forced to.
60W is insanely easy tho, pretty much anyone without some sort of extreme physical limitation would be able to do that.
Indeed. Thomas De Gentd averaged 298w for 6hr on stage 17 of the Giro d’italia a few days ago according to his strava feed (measured off his SRM powermeter).
Great idea! We could also add some AI and then connect it to the power grid, and people could earn something while watching virtual worlds on their screens and providing baseload generation to power all the machines.
Magnetic resistance bikes should be good for this cause, just make use of the induced current and don't turn it into heat (which I presume is what they do).
> Actually, generating power with their muscles provides a valuable lesson for kids, whether or not the power goes out.
The article ends on this point about parenting philosophy, but I think the author does not set up or discuss it enough.
What I don’t exactly understand is the underlying suggestion to manufacture this project as a “hard lesson” for the children.
I believe it is widely understood that children learn very much by emulating their parents. So what the parent regards as important, their children will see, and internalize those behaviors.
When I see parents worry about children taking something for granted, it can look like parents feel regret about parts of them that they see mirrored in their children.
How cloudy does it have to be for a 3rd <$100 solar panel to provide less than 0.06 kWh of charge over 1 day? Clear skies are of course always better but I don't think I've ever heard just how bad it is when they aren't.
Depending on your latitude, in the winter on a cloudy day a small DIY system might be near useless. The panels might have a voltage when short circuited, but getting enough power through the DC-to-DC converter with enough leftover to overcome the internal resistance in the battery would be a tough. At best, it might trickle charge the battery and keep it from losing charge from self-discharge.
The advantage to the bike is that it not only covers the days where the solar is falling a little short (and where an extra panel would also work), but also on the days where the solar is failing to produce anything of significance (at which point you would either need a ton of extra panels, but even then you still might not be covered).
From my experiments making my own, got around 100W of power.
For reference, a laptop is around 30watts, charging a cell phone around 5w, electric shavers, fans for air circulation, small monitors are also game, so there are things you can power.
Storage can be achieved with a blocking diode and a supercap, or more conventional easily obtainable battery charging circuitry.
The article wanted to use these as supplementary power, and so during an emergency wouldn't be far fetched for bike-power to be useful.
That being said, for sustaining refridgerators (always on), or for using large power draw of washing machines, dryers, and microwaves, one would definitely need to rely on more than just biking (e.g. stored wind or solar as you pointed out).
But again, bike power can be useful as a backup or for emergencies.
I think the novelty here that justifies the article is that this article challenges the oversimplification of "unsustainable" into "useless".
This is an argument that bicycle generators can have value in some specific, non-critical instances, like when you already cycle daily and aren't very familiar with how to build and maintain a wind or water turbine (as you suggest).
The author claims to have 200 watts of solar panels but only 420 Wh of battery, and because it's lead-acid only half of that is really usable. Unless they live somewhere that only gets 1-2 hours of insolation per day [0] that is nowhere near enough to store an average day's generation. Likely most of the energy is likely being wasted.
When energy gets dug or pumped out of the ground so cheap, you forget how hard it is to generate 100W, and what you're calling on in resources every time you turn on lights or drive a car.
If you want a sustainable intermittent power source and you don't have a stream nearby, you can't do better than a solar panel. They're ridiculously cheap these days and, with a bit of battery backup, are a far more practical electricity source than human muscle power.
The game features "duplicants" in a futuristic scenario trying to survive in deep space.
The first technology to produce power is a sort-of hamster wheelie that one of them has to cycle on to generate power.
You could try to somehow attach the generator directly to the pedals/crank, that way you won't lose energy to the chain and the bearings on the rear wheel.
It's probably not a meaningful improvement if the bike is well-kept and the rear wheel is lifted from the ground.
They're doing the trip from the tip of South America all the way to Los Angeles on a pair of prototype electric Harley Davidsons. The support crew is in a pair of prototype Rivian pickup trucks.
The Rivians have a "tow to recharge" mode that they've used several times already in the first half dozen episodes.
The show is great and I'm as fascinated by their dedication to do the trip on electric bikes (the first parts of the trip were in freezing and sub-freezing temps in areas with long distances between grid electricity availability) as I am by the scenery and their narration.
Anyway, sorry for the tangent, but the title reminded me of the series. I hope it escapes AppleTV+ so that non-Apple folks can watch it at some point.
Lets be reasonable and say 160W (somewhere between all the ratings strava gave) avg for my 2 hour trip.
I think I am a pretty strong rider, at the peak of the season I can beat electric bikes on flat ground as my top speed is higher then theirs (I dont have a speed limiter, they do)
I can tell you this is NOT easy and once you realize how much physical effort it is you appreciate being able to plug things into the wall.
it is the sustained power output that will kill you.. You can probably dump 10w of power for a long time, but putting out serious power for extended periods of time isnt easy.
“One kWh” sounds like a tiny amount, but it is 3,600,000 joules. If you want to store that as potential energy, you must (taking g=10m/s²) lift a mass of 360,000 kilograms by a meter.
Another way to see how large a kWh is: a human body, ballpark, needs 3kWh per day (125W an hour)
⇒ If you want to produce 3kWh a day, you’d have to eat twice what you normally eat.
And that, even ignoring heating and airconditioning, doesn’t power an average household in the western world.
(Primary power consumption in the US is about 10^20 Joules per year, that's around 9.7kW/person).
I actually built a bicycle generator (an AC motor with a belt around the rear wheel) and would sell organic smoothies at music festivals. The fun part was the buyer had to pedal the bike to generate the electricty to power the blender to make the smoothie.
Even with only a 150w blender, fit adults had to work HARD to get the smoothie.. well.. smooth.
Kids basically couldn't do it, or not well enough.
And that was about 20-30 seconds of pedalling.
But I wanted to build it the way I did to be educational as well. When kids struggle after 15 seconds I say "You'd have to pedal a LOT harder continuously to power your xbox. That really gets them thinking.
I was super in to cycling a while ago and I was only able to average 200w over an hour but thats not quite accurate because I was going super hard and then taking rests every 20mins which stops the clock.
Just about any human in decent health could probably cycle long enough (with effort) to charge a battery to provide the requisite energy (over the course of, say, 30 minutes) and then output that energy at high power to toast over 3-4 minutes.
I think that may be some usable numbers for what an avid amateur cyclist can achieve (ftp ~4Ws/kg). And then one will have to take into account that the body efficiency of cycling is about 25%, so one will have to eat 4x that amount in calories...
I was roped into a team entry for a Half Ironman. Despite being more of a runner, I did the 90 km bike leg which was effectively a solo "time trial" (no drafting allowed) on a standard road bike with clip on aerobars. After averaging 35.0 km/h on the mostly flat (~600m elevation gain) course, I was exhausted. The SRM Powermeter I borrowed for the race said I had averaged a "measly" 215 W!
e.g. USB phone charger rated for 5V/2A = 10W, laptop adapter for 19V/65A = 1.2kW, electric heater rated 110V/15A = 1650W
Voltage and current are like height and width of a 2D box named wattage or energy, and you can stretch or shrink the height thus changing width, but not the total area
my i7-6600u idles at around 3W
Check this out: olympic (cyclist) sprinter powering a toaster! it's intense.
https://www.youtube.com/watch?v=S4O5voOCqAQ
I don't mind these kinds of "solutions", but I do object when they go in the "make me feel guiltless about everything else I do because I hooked my bike up to a generator" bucket.
Certainly, running a vacuum or boiling water won’t work with human power generation, but if you want that as a backup, you probably can fall back to a broom and use a gas/multifuel cooker in the meantime.
> Literally forgetting to turn the light off in your bathroom twice a month
8h * 5W * 2 = 80Wh per month
(Unless you're talking about using incandescent light bulbs, which would be like using a 4mpg vehicle in a discussion about average vehicle efficiency. Personally I think a 3W LED is better than a 5W, but I know most people disagree.)
Our main bathroom light draws, I'd guess, 0.1W. It shows up as 0.0 with a kill-a-watt so I don't really know. And it's only used for about half an hour a day at most.
> a super-committed, hour-every-day stationary-bike-using person
60W * 1 * 30 = 1800Wh per month
So no, forgetting to turn a light bulb off for an entire night, twice a month, does not waste more electricity than that gained by a cyclist who is capturing their electricity.
I think it's a great hack to turn this machine into an electrical generator.
Regardless, it's just an example. The DoE says the average US residential customer uses 909 kilowatt hours per month. Using your math of a committed cyclist that generates 1.8 kwh per month, you're still looking at under .2% of energy replacement. Which, again, even the smallest efficiency improvements in a house would completely dwarf what a human could produce.
Now, we already discussed generating 1800Wh per month using this bike. So:
1800 / (8 * 2) = 112.5
Or in other words:
112.5W * 8h * 2 = 1800Wh
So you'd need to run a 112.5W light bulb for 8 hours per night, twice per month, just to equal the amount of electricity produced by the article author. Although you said that leaving the light on wasted more, so, let's just go with a 113W bulb. I'm old enough to remember 100W incandescent light bulbs, but even then, they were rarely bought and used because that's an insane amount of electricity for indoor lighting.
Now where I live I can't even buy incandescent bulbs because they're not for sale. For 112.5W to be average, there would need to be millions of Americans using stadium lighting just to take a shit.
I think you should take a step back and reflect on why you're so quick to attack someone for doing a cool hack (this is Hacker News) that reduces their electrical usage (in the time of climate change).
1800 watt-hours, or 1.8 kilowatt-hours, is 20 cents worth of electricity. Using a cycle to power things makes for a neat demo, and might be good for educating people about electricity and suchlike, but anyone who expects to notice it on their energy bill or carbon footprint, or even for the installation to pay for itself, is off by a few orders of magnitude.
I haven't done any research or taken measurements, but particularly the low-end style tyre-on-roller that I have must be awfully inefficient.
It's been briefly popular (to some extent) a couple of times to power a light while cycling. These things don't typically have large capacitors or batteries to store surplus charge, because powering the light is about all you can do! (Ok not totally fair since you're also cycling, but still.)
The power from the bike is likely to be more than sufficient for those use cases.
Incandescents are a hard sell when LED bulbs are $1-$2 and pretty reliable.
Question - where did you get 5W from? a LED nightlight?
More realistic, a washroom is using 60W MINIMUM.. most have those light bars above the mirror and they are closer to 300W.
I recently replaced my Halogen lights with LED and cut the kithen lights from 600W to ~60W. Substantial savings, but how many people replaced everything with LEDs?
5W.
Above the mirror we have three huge bright bulbs we only use when brushing teeth.
5W each, or 15W total.
I literally don't think I've been in a house in the past 3-4 years that isn't 90-100% LED bulbs.
However, on average, that will not be a primary driver of energy usage in the average since most people don’t spend a substantial chunk of their time painting their face.
I hate the light that LED bulbs give when I'm getting ready for bed. Thus, I have LEDs in most places in my house except for my bathroom and bedroom where I have incandescents.
"But what if skies remained gray for many days in a row? Rather than trying to purchase enough battery storage to cover all reasonable eventualities, I decided that my backup source of electricity needed a backup itself, one that I could use to charge that battery during times when my photovoltaic panels won’t function"
As a primary source of energy a cycle generator doesn't make a lot of sense. But as an on demand source to cover occasional periods of low solar generation it's a great hack.
Even though it won't run your refrigerator, I would have been pleased to be able to plug an external mobile device battery into a smart trainer during a recent power outage so i could continue to work on a book manuscript while power was out.
;-)
As the story goes, the movie executives thought this would be too difficult for most people to understand, so they switched it out and used the thermodynamically unviable power source motive instead.
Humans have finite lifespans, right? So all the AI has to do "relieve" itself of the burden of keeping humans alive would be to not let them reproduce. This would be pretty easy considering that it's pretty hard for people to spontaneously become pregnant while hooked up to those pods.
(For mere mortals, it will be indeed closer to 100W.)
In my experience with Comcast Business Internet, their upstream equipment goes offline a few minutes after a power outage. So regardless of how you're powering your own equipment, it's hopeless.
The cell network appears to persist through power outages, but bandwidth, packet loss, and jitter aren't ideal in the best of circumstances. When it's the only Internet access for the whole neighborhood, you should probably just give up on your videochat meetings...
Its kind of weird sitting in the dark with absolutely no communication ability.
https://en.wikipedia.org/wiki/2016_South_Australian_blackout
Unfortunately, since late September, solar can't keep up. (Not a surprise given my suboptimal conditions.)
A bicycle as a generator would probably allow me to have a bit of exercise and easily provide enough power to get my blog through the day.
1: https://louwrentius.com/this-blog-is-now-running-on-solar-po... 2: https://louwrentius.com/solar/solar.png
One thing to keep in mind about power numbers vs pro cyclists is that they can churn out these kinds of watts at significantly lower body weights than a recreational cyclist. For output into electricity though it doesn't matter if I’m 35lbs heavier than a pro because watts are watts.
Regardless it seems to me that these levels of output using a full body motion of a rowing machine would be exceedingly difficult for a one hour period compared to cycling that leaves most of your muscle groups relaxed.
I think the best multi-hour total energy yield efforts are from recumbent bicycles.
Regular recreational cyclists can generally put out 200-250W for well over an hour depending on weight.
I'm not much of a rower, but after your pull, pulling your body forward for the next row is all wasted effort as far as producing mechanical work. Cycling doesn't really have any wasted phase like this.
Here's a bunch of rowers comparing their cycling/rowing watts: https://www.c2forum.com/viewtopic.php?f=31&t=186612
What I'm not sure is if you were to measure total energy expenditure at the human (as opposed to the spinning wheel), then cycling/rowing might be closer.
Still of course the power is low comparatively to traditional sources.
The generators I've found online seem kinda whimpy and just slide on the exterior of the tire/rim. Is there is something more hardcore I can put on the chain or something?
https://hollandbikeshop.com/en-gb/bicycle-wheels/front-hub/d...
For comparison, I'm reasonably trained, and could maybe hold that for 4 minutes. I'm also considerably heavier!
I would guess that a random average adult male who doesn't neglect general fitness, but doesn't necessarily cycle, could put out 160w-220w for an hour if they were forced to.
60W is insanely easy tho, pretty much anyone without some sort of extreme physical limitation would be able to do that.
be sure to note the size of his thighs
https://www.youtube.com/watch?v=aoQnTypHbYk
333w for 6.5h, 460w for the first climb (35 minutes).
https://en.wikipedia.org/wiki/Maximum_power_point_tracking
https://en.wikipedia.org/wiki/Continuously_variable_transmis...
What could go wrong?
The article ends on this point about parenting philosophy, but I think the author does not set up or discuss it enough.
What I don’t exactly understand is the underlying suggestion to manufacture this project as a “hard lesson” for the children.
I believe it is widely understood that children learn very much by emulating their parents. So what the parent regards as important, their children will see, and internalize those behaviors.
When I see parents worry about children taking something for granted, it can look like parents feel regret about parts of them that they see mirrored in their children.
The advantage to the bike is that it not only covers the days where the solar is falling a little short (and where an extra panel would also work), but also on the days where the solar is failing to produce anything of significance (at which point you would either need a ton of extra panels, but even then you still might not be covered).
https://www.youtube.com/watch?v=SsmQaVSYx-c&t=555
The Nissan Leaf can be used to power your home. Useful if you want to keep your fridge running in an extended power outage:
https://www.youtube.com/watch?v=x78XGElU2I0
https://thedriven.io/2020/07/09/nissan-leaf-owners-should-be...
I think more could be gained by a small wind turbine or even a small water turbine, although those are definitely more complicated.
For reference, a laptop is around 30watts, charging a cell phone around 5w, electric shavers, fans for air circulation, small monitors are also game, so there are things you can power.
Storage can be achieved with a blocking diode and a supercap, or more conventional easily obtainable battery charging circuitry.
The article wanted to use these as supplementary power, and so during an emergency wouldn't be far fetched for bike-power to be useful.
That being said, for sustaining refridgerators (always on), or for using large power draw of washing machines, dryers, and microwaves, one would definitely need to rely on more than just biking (e.g. stored wind or solar as you pointed out).
But again, bike power can be useful as a backup or for emergencies.
This is an argument that bicycle generators can have value in some specific, non-critical instances, like when you already cycle daily and aren't very familiar with how to build and maintain a wind or water turbine (as you suggest).
http://www.bigfrogmountain.com/SunHoursPerDay.html
The game features "duplicants" in a futuristic scenario trying to survive in deep space. The first technology to produce power is a sort-of hamster wheelie that one of them has to cycle on to generate power.
Very funny game.
It's probably not a meaningful improvement if the bike is well-kept and the rear wheel is lifted from the ground.