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Could We Run Modern Society on Human Power Alone? (lowtechmagazine.com)
69 points by MaurizioPz on May 29, 2017 | hide | past | web | favorite | 100 comments

This will never, ever make economic sense. Human labor is orders of magnitude too valuable to waste on power generation. A fit man can, in an hour, produce about 400 watt-hours of electricity, worth about $0.05; his labor would be worth at least $10 in a developed country. In the unlikely event that all modern technology ceased to exist, we would revert to using animals and wood for power, like they did in the 1700s.

> A fit man can, in an hour, produce about 400 watt-hours of electricity

That's not "a fit man" that's a trained and fit cyclist, good marathon runners (2h15) were measured at an average 300W over the run[0], a fit adult might reach 200W.h over an hour or two, over long periods of time (e.g. an entire workday) you won't get much more than 100W.h if even that, an average fit labourer would be around 75W.h.

And that's mechanical in all cases, not electrical, you then have to factor in conversion losses. While a large rotary generator is ridiculously efficient (98~99%) it doesn't scale down that well (you'll be at about 80~90% at the generator output) following which you still need to remove the losses from the voltage regulator, battery, and possibly AC converter.

And then you still have the issue that your base energy sources (people) is not really efficient at converting food to mechanical energy in the first place.

Frankly, you'd be better off with a team of draft animals powering a big crank/wheel (with a flywheel for regulation), the average draft horse can produce ~740W (1hp) sustained. There's a reason why they (and oxen and other beasts of burden) have been used until engines became a thing.

[0] http://running.competitor.com/2016/11/photos/understanding-r...

Yeah, I was humbled by the claim that a fit man can produce 400 watt hours in an hour. I was recently struggling to hit 550 watts PEAK doing row machine intervals for 10 minutes.

That's not surprising. If you do 550W consistently during 6 minutes, you do 500m splits of 1:26 (http://www.concept2.com/indoor-rowers/training/calculators/w...), or a 2000m in 5:44, which is 'only' 6 seconds from the world record (http://www.concept2.com/indoor-rowers/racing/records/world/2...), and would probably draw the attention of most Olympic rowing teams, even if you can't row at all currently (for the larger boats, it is easier to learn a strong man who is willing to do a 2k that fast to row than to make someone who can row that strong and/or that motivated to compete)

('Only' because you need to do 580W to gain those six seconds. 2% faster = 6% more power)

I can hold over a HP for a minute, and that's it, I need to go throw up. But it was a fun goal.

Someone producing 400W for an hour is not a fit man, it's a star endurance athlete. It's the kind of power top performer in tour de France can provide.

Indeed. At a local nuclear power station there's a visitor center where one can experiment how to generate electricity with an exercise bike. With moderate power you can power a tablet computer or an incandescent light bulb, but the water kettle comes on only with actual athletes, and even then, the small light bulb goes off, and even a professional cyclist can't sustain that power for longer than a brief moment.

It's just pointless to generate electricity by human power. It's not pointless to ride a bike.

Yes, as a benchmark an 80kg male rider that's an athlete but not a pro (say cat1 or cat2) can produce maybe 1200-1300 watts for 10 seconds, and maybe 400 watts or so for 5 minutes.

Not to mention that a Tour de France Athlete is consumed during the Tour. You need to accumulate reserves for at least three months in order to last 23 days of effort.

they could do 400 watts for one hour a day indefinitely though.

Bradley Wiggins in the most recent hour record attempt averaged 440 for an hour.

440 watts for a world hour record.

350 watts for one hour, once a day, would be challenging to maintain for one week.

It takes an Olympic Cyclist mashing until he has to lie down just to make a piece of toast.


On a good day my house uses 8kwh, I suppose I'd qualify as an endurance athelete after pedaling 20hrs a day for a bit.

You're right that it doesn't make economic sense. It also doesn't make scientific sense.

First of all, human power releases tons of carbon dioxide just like burning fossil fuels does [0].

Second of all, modern society currently depends on burning millions of years of stored sunlight energy in a matter of centuries (i.e. fossil fuels). Human power doesn't begin to compare. Bang Goes The Theory (BBC show) did an entire episode on this. It's shocking how many bicyclists were needed to run a tiny household [1].


[0] http://www.livestrong.com/article/402142-how-does-exercise-a...

[1] https://m.youtube.com/watch?v=vPxuuB_ZBuk

> First of all, human power releases tons of carbon dioxide just like burning fossil fuels does

I was disappointed that for all its calculations, the article completely avoided the question of "How green is human power?" Instead, it just repeated "could become one of the cleanest energy forms available".

But they had to, of course - answering that would have destroyed the entire idea. Fueling humans burns a huge amount of carbon, and neither the food > muscle conversion or the muscle > electricity conversion is even passably efficient.

The carbon that humans exhale is already part of the carbon cycle. So equilibrium CO2 concentrations don't change, so it's not an issue pollution wise.

(This is assuming you didn't use a bunch of fossil fuels to create and transport food in the first place, and you're instead using human/animal power to do that.)

However, using humans as power source would increase the amount of food consumed, and co2 exhaled, so this analysis would need to take at least that incremental co2 into account.

Challenge accepted.

On a bike I can do around 220W for an hour, and 160W for an indefinite period (have done up to 12 hours before).

Biking is known to be 20-25% efficient from calories burned to power at the wheel, so that's ~700 kCal/h for an hour at 160W. My idle consumption is ~1600 kCal/day, or roughly 70 kCal per hour, so riding on the bike uses 10x as much; therefore I'm going to be producing 10x as much CO2 (obviously).

It takes ~140 L of oxygen to burn those ~700 calories, resulting in ~110 L of CO2.

So if I do a 4 hour ride at 160W to produce maybe 600Wh of energy after conversion inefficiencies, that's 2800 kCal just for the ride and 4400 kCal for the whole day, around 2.75x my idle consumption.

Disclaimer: I've done this quickly. Feel free to point out any errors.

> Whether a human eats the plant or it decomposes naturally, the same amount of carbon dioxide is released.

Yes, but we produce agricultural crops to meet demand. If as per the calculations above, every human suddenly started consuming 2.5x as much food, we'd have to grow more.

And yes, this is part of the carbon cycle. The problem is that we use fossil fuels and release CO2 above and beyond what's part of the normal cycle.

Whether a human eats the plant or it decomposes naturally, the same amount of carbon dioxide is released.

That would be fine if humans simply walked around consuming plants that would have otherwise decomposed and there were no other resources associated with food production.

Unfortunately, agriculture is a major driver of deforestation (and forests are excellent at actually sequestering carbon in the ground). It also requires trucks, boats, and planes to haul supplies to farms, work the land, move water around, and transport the produce to stores. You have processing and packaging that rely on fossil resources (paper, plastic, metal cans...)

That doesn't even touch on the impact of meat production, which is several times worse for the environment.

Food consumption is absolutely not carbon neutral. You're far better off taking public transportation to work (if available) than walking or riding a bike, if you care about the environment.

Not to mention that muscle is really really bad at energy conversion. We would be better off designing bacteria to turn plant matter into gas.

This is True, but just for genetating and selling electricity on a market. By contrast, Cycling or taking stairs can still make great economic sense, or even much better sense, than driving, when deciding to produce or purchase energy.

I sold our 2nd car, and just ride to work now. But if we just compare human fuel aka food with vehicle fuel, it's actually more expensive to ride!

But it's all the other costs of owning a car that make it so much more expensive: depreciation, licensing, registration, maintenance, blah, blah.

Hmm depends on which fuel you choose to fill up with. Assuming we choose the cheapest option, a litre of clean burning canola oil can carry you 91km assuming 30 calories/km and 2750 calories/litre @ <$2/L that's a lot better than a car even before ownership and other per mile costs.

But most people are in an unwanted caloric surplus so it's really even better than this for those people.

I'm in Australia, and in our car it works out to about A$0.13/km in fuel. So yeah, you're right there.

I choose not to drink pure canola oil because reasons. But if I did, my ride to work would be fueled by 30mL - so I could maybe just start taking a shot in the morning and a shot in the evening. Yummy.

Haha - well if we're going to talk about practicality - it doesn't need to be as tasteless as that - it reminds me of the ultra endurance swimmers sucking hot oil through a tube.

You can just make some delicious fried or oily snack, like crisps or chips or sauteed spinach, or fried what-have-you.

...but even a shot of oil is more healthy, pleasurable and hygenic (assuming you burn it all) than filling your tank with petrol :)

I love endurance; riding and running. But even an hour swimmingly bores me to death, can't imagine doing those 10km+ swims. Hot oil through a tube... TIL and ewww.

Note that people pay to waste their energy in gyms.

you can pay obese people to lose weight, but you can't have something like that everywhere.

Stairs on one side and something like a waterwheel on the other. Charge less than a gym and sell it as partially powering whatever local association/charity could do with a break. Credit me when it's a thing heh

Proceeding along this train of thought, they've already made a TV show episode out of it : https://en.wikipedia.org/wiki/Fifteen_Million_Merits

I know this is a joke, but I wonder if this concept - a gym where the machines generate power - actually could be a thing.

It's greener in a pleasantly 'immediate' way - i.e. you could quite literally be keeping the lights, music system, etc on at the gym :-) And what's more, assuming power costs are a non-trivial overhead, it could even result in lower membership fees.

If somebody opens a gym like this, sign me up!

The gym that I go has machines that are almost all self-powered, with the exception of things like thread mils for obvious reasons. So if you jump on a stationary bike none of the electronics will turn on unless you start pedaling, and to get the fan going you have to pedal for a minute or so first.

that would be cool, you power the batteries and those batteries light up the gym and power the usb sockets the the user's phones.

I think people are missing the fact this is being run by an art collective. It is trying to ask questions and show what sort of compromises people might need to make if/when other energy sources are off the table. I love it.

As an art project, it's neat. But when it starts to sound like it actually believes its claims that human power can provide the energy needed for modern society, then you can't help but roll your eyes.

Right off the bat, the sentence "Unlike fossil fuels, human power can be a clean energy source, and its potential increases as the human population grows." This is utter bullshit. The modern food supply is dependent on huge amounts of fossil fuels and mined minerals to create fertilizer. Much more oil just goes into feeding a human than you'd ever get out of him.

> when other energy sources are off the table

Hu? Where do you [they] think the human power comes from? It comes from food - you could just burn those plants for fuel, and skip the useless multiple conversion.

What does flowing the energy through a human accomplish? It certainly doesn't change the energy source.

I understand the Haber process. I don't think most people know of or care about it. The point their making here is without the magic of current energy supplies things get very weird and difficult, even then you try really hard.

"Most work, however, we carried out ourselves."

"a human needs to be motivated in order to produce energy."

Historically, "ourselves" was equivalent to "members of a disfavored ethnic group and/or social class" and the "motivation" was provided by guys with swords, whips, pistols, etc.

I'd rather not see routine slavery/serfdom come back, thanks.

They specifically address your point; you didn't read it.

But they don't, unless I missed it, address the death toll of large-scale, human-powered construction projects like the Panama Canal (5,609 dead). To me it reads like a romanticization of brutal working conditions, and waving aside the issue of slavery by saying "but we can make it fun!" doesn't really help.

No, they don't, and yes, I did. Bikini babes aren't going to make someone pick cotton by hand in the Alabama sun for 12 hours a day. That job won't ever be "fun" and "exciting". To be blunt, it sucks major ass.

Handwaving doesn't count as "specifically addressing". Sorry.

>If students have to generate their own power, they are much less likely to waste it. How far would students go to reduce their efforts? Would hot showers go out of fashion?

The article's discussion of human power and incentives to use it beg the point to be made about the right way to fix the tragedy of the commons market failure with atmospheric pollution (and all the other problems with fossil fuels as well).

There are so many ways to reduce energy consumption that government regulation can't possibly legislate and adequately regulate (and it's barely even trying at the moment).

For example, I try to make a point to bike, walk, take the stairs, use efficient driving habits, and try to often take cold showers. I admittedly do this primarily because I like the exercise, the cold water is more refreshing and better for my skin, I save money, but as as an added bonus I feel some satisfaction that I consume less fossil fuels. But I would do all these things more if I saved more money from it.

And taxing bad things is better than taxing good things (like income and investment).

I think this is one of the things we will look back from the future and think, what were people thinking--they taxed jobs when they could have taxed something like environmental destruction? What?

But American politics are what they are. Our public transport across the country varies, but generally it is laughably bad, and that's just another example of an extremely low hanging fruit to grab.

The tragedy of taxing bad things is that if the taxation works, and the bad things (e.g. pollution) start to go away, then the government loses tax revenue. And for the government, that's worse than any pollution.

So we see all governments going through loops and hoops to tax something bad, and at the same time regulate so that a sufficient amount of that bad thing still happens so they wouldn't lose the tax money.

Of course, this can be limited by requiring funds for a specific purpose, such as mitigating pollution. While far from perfect, gas tax going to pay for roads is a decent feedback loop.

Tax 'bad' thing, to pay for education about or mitigation of 'bad' thing. the feedback loop solves itself.

>then the government loses tax revenue.

Actually, this would not always be true. Yes, in many cases would, but it would depend on the elasticity of supply and demand. The total size of the tax incidence would be government revenue from the tax.

The idea is not necessarily to outlaw carbon emissions, but to set a tax equal to the economic burden the emissions place on the global economy.

But a tax such as this should be designed to be revenue neutral--which we as humans are capable of doing.

Even though these things are possible, economic policy is so filled with politics, and politics is so filled with corruption, that I have little to no hope it will change.

gov can just keep finding new things to tax.

Pff, "modern society". Most hunting populations have been calculated to yield 10kcals of food for every 1kcal of expenditure --- our fancy modern fuels OTOH result in more like 1kcal food yield per (non-edible of course) 10kcal expenditure. Not exact figures of course but the difference is that profound. "Human power" thus "wins", then --- but not to "run modern society", of course.

Here is a guy who has experimented living 'energy positive' for many years[1]. Meaning he tries to get more energy out of farming that he puts into it. In his calculations it does not make sense even to use a horse. Seems pretty tough, I think hunting and gathering would be easier way to go if you had access to the land.

Good writeup, but unfortunately in finnish.


(google translate) https://translate.googleusercontent.com/translate_c?depth=2&...

How is this a useful comparison? It's 10kcals of ingested food per 1kcal of energy the hunter expends (not including e.g. the energy of the game). By that measure, I'm super efficient cause I buy food at the supermarket, and don't really expend any energy for it. That number has nothing to do with the second 1kcal/10kcal modern figure.

You're not wrong, it "doesn't really matter" as long as our fuels do keep up with our species' (consumption, production & reproduction) growth.

Exactly. Going back to hunter-gatherer and living off the land like that is hardly sustainable with the current population: Earth has 5.7e7 sq mi surface, but 7e9 people, i.e. 8.1e-3 sq mi/person. Hunter/gathers seem to need (after a short google session) need around 1e-2 (Tropical) to 1e2 sq mi (Savannah) per person.

This might be more accessible if you weren't using scientific notation. They aren't exactly astronomical numbers

That doesn't seem right - surely a modern animal farm yields more food per energy expended than a group of hunters?

Anthropology classes teach that the parent comment is true: hunter-gatherer societies are much more energy efficient. Every step of modernization, from animal to machine power, decreases energy efficiency but increases intensity: food can be made more quickly and in less space. Consider that animals are more powerful, but require food and water of their own. Tractors are more powerful still, but require fuel, steel, and huge industries that bring those two together.

The best citation I have off hand is this https://anthropology.artsci.wustl.edu/courses/wucrsl/L48/361...

It does make sense when you consider where the energy all comes from: the sun.

Plants absorb solar energy and store it as chemical energy. Animals roam far and wide to eat those plants, collecting the chemical energy in one place- themselves. Then human hunters come along and simply 'pick' the energy from the dense source that is the animal.

Now, the humans don't need to do much work because the energy is all in one place (they just need to find that one place). But the energy itself was collected over a huge area.

Tractors and fertilizer inputs to the feed, of which only a fraction ends up in the meat (https://en.wikipedia.org/wiki/Feed_conversion_ratio). Things like eggs and crickets are very efficient, with about 1/2 the feed energy ending up in the product.

For beef it is more like 10-15% of the feed energy.

Interesting stuff.

I guess the advantage is that you don't have to rely on nature and chance to get that food, since you literally create it from scratch.

citation needed

I think the fatal flaw in the argument here is that the hunted animals are seen as a magic free resource; in reality of course they're a limited resource taking up valuable land, and we could never sustain 7bn people or anything like it in this way.

How's that a "flaw", I wasn't advocating one thing or another. Of course 7.4 billion and growing cannot feasibly all enjoy the bountyful abundance of game and leisurely pace of our pre-neolithic ancestors (or North-American natives etc) =)

It's still a plus to acquire just another added perspective on fuel yields for different types of human societies and lifestyles

I don't think so. Only 10-20% of the energy we get from food can be used for manual labour, and that's neglecting rest and sleeping periods. If what GP is saying wasn't true, hunter populations wouldn't be able to survive.

This is also why reduced calorie intake is much more effective than increased activity if you want to lose weight.

Yes of course.

Rick and Morty covered that in this episode.


IIRC Soylent Green had the characters cycling a stationary bike to generate power for their living space.

And Black Mirror too.

Referring to the episode "Fifteen Million Merits". IMO it's one of the greatest dystopian works ever.

And the Flintstones.

...and it's blocked.

> For extra motivation, all exercise machines in our prototype human power plant are facing a jacuzzi & shower where girls are invited to encourage the boys to flex their muscles and generate more power. Of course, the gender roles could be reversed, but during the first experiments we discovered that this is less energy-efficient. Girls don't seem to get motivated by guys in jacuzzis, at least not to the extent that guys get motivated by girls in jacuzzis.

Clever, but I'm guessing many will find this creepy or 'problematic'.

I don't see how acknowledging and using differences in psychology between men and women would be problematic. Could you please explain why you believe it would be?

To the extent they are describing observed behavior, it's not problematic. However, stating generalizations in a flip, cliche-confirming way _can_ be problematic, inasmuch as it reinforces the negative stereotypes.

In this particular example, I certainly have no problem believing that it's true that among contemporary college-aged individuals from American and European cultural traditions, that on average the men would be more motivated to work out harder by the chance to see scantily clad women in a jacuzzi than the reverse. But that's extremely unlikely to be true for _all_ men or _all_ women. I would doubt that it's true for homosexual individuals. I would doubt that it's true for people raised in cultures that aren't so open to the display and ogling of near-naked humans, or contrariwise, cultures wherein the display of near-naked human form is not so sexualized.

This statement would be a cute aside between two people who share a similar cultural background. But in a semi-scientific article describing a utopian vision of power generation, it feels out of place to me.

From a global point of view, it's narrow-minded. The generalization given is not true of all cultures. From an individual point of view, generalizations about men and women who do share our culture tell us nothing about the individual in front of our face, who may or may not personally fit in with the profile. From a camaraderie-building point of view for residents of the building, making decisions about how to run the residents' responsibilities based on sexual objectification of other residents is probably not going to build a healthy local culture. And from a purely practical point of view, ignoring individual preferences and motivations is a great way to get substandard performance from everyone. Maybe the chance to see the girls in the jacuzzi would motivate the guys more than the girls, but I am betting it's unlikely to be the best strategy to get the best performance out of each individual man and woman.

The point is, it's a mistake to embrace these generalizations as universal truisms. They are anything but. And relying on them leads you to make poor and sometimes hurtful assumptions about other people.

The poster isn't talking about absolute truisms, but generalities. And generally, men tend to be less selective towards their mates than women due to sexual dimorphism. And yes, those differences extend into psychology[1]. Acting like there are no norms between the sexes in an attempt to placate those outside the norm goes too far. Yes, we need to be accepting of those who aren't normal, but that doesn't mean we need to ostracize the majority of normal people in the process.

[1] https://en.wikipedia.org/wiki/Sex_differences_in_psychology

Because it's adversarial? Because not all men want to flex their muscles for women? Because it makes assumptions about group psychology that don't hold true? Because it turns an entire gender into a carrot on the end of a stick? Because people can be lazy or tired? Because you can get laid easier without expending energy? Jesus christ this is a stupid thread.

You wouldn't - men can only see in black and white.

I hope you are kidding. If you aren't, then you're falling into the same us-vs-them mentality that led to the persecution of Jews during WWII and racism against blacks in America. This method of pushing against literally half of the entire population will lead to backlash against those who think like you, distracting from real social problems that could actually be addressed.

My statement was exaggerated to make it obvious that I was employing humor. I'm doing exactly the thing that you are claiming isn't problematic, and yet you somehow don't like it.

And now you are complaining about people falling into an us-vs-then mentality while at simultaneously falling into an us-vs-them mentality yourself.

What I actually think is that current social justice thinking is as harmful as you seem to imply but that the way you are responding to it is literally just as bad.

We need an advance in our ways of thinking about this - not just un-thought-out reaction.

I see. Just so you know, it's tough to portray subtle humor like that while being so succinct. There are many people who legitimately feel that way.

I would like to point out that what I said and what you said were different. I spoke of norms and tendencies, while you took a black-and-white approach. I agree that there needs to be a middle ground found. Extremists on both sides make progress difficult.

What I did was to use a difference in psychology based on gender. Sure it was blunt and inaccurate, but psychology is generally pretty weak like this - see the replication crisis - so it is important to be careful not to use it out of context. You didn't speak of norms and tendencies.

I'd like to point out that you have doubled down on the us-vs-them mentality.

Extremists are doing absolutely nothing to prevent you from coming up with a better way of looking at this problem.

Very likely. So?

> Each student in the human powered Van Unnik student building is responsible for generating the electricity that’s used in his or her individual room.

No elderly or physically disabled students need apply.

You think it's eevil for people to generate their own power, because not everyone can do it?

Makes sense that they'd try this in the Netherlands. The Netherlands has a very high mode share of active transportation (walk/bike). For example, the walk+bike mode share in Amsterdam is 56% (chart includes other cities in Europe): https://charts.datawrapper.de/JsIir/index.html#embed

By contrast, most US cities are well under 10%. Even LA, which has pretty excellent weather overall, is only at 4%: https://en.wikipedia.org/wiki/Modal_share

LA is a bad example, as it's also notoriously a car-centric city that is unfriendly to walkers/bikers. Better example would be something like Portland.

> a car-centric city that is unfriendly to walkers/bikers

1. This is true of nearly all cities in the US, and

2. This feeds into my point about cultures favoring physical activity or not. LA's geography/weather is great for walking and biking. What holds it back are intentional design decisions borne out of culture.

But it's cheap to build bicycle infrastructure so LA can get there too.

The post-global-warmjng sci fi novel The Windup Girl by Paolo Bacigalupi deals with this scenario: all energy is measured in calories and workers prepare clockwork springs that store energy to power devices. It's a great novel, too.

Which is wildly unrealistic of course. There’s no material that can take the tension such springs would have to cope with. Lots of SF books ask you to take one or two impossible things as givens in order to tell the story of course, but this one pushed things a little far for me.

The repeated "lets rape the sex bot again" scenes didn't help either. Funny how when she gets her revenge, that’s not described at all, just the aftermath. But we get page after page of lascivious detail on her abuse. Frankly, it left a really bad taste & I didn’t want to read anything by the author in question ever again.

The very technology of the spring winding is a McGuffin in the story.

well, no: unless the whole campus is also built without machinery, you're trading upfront energy (building with more insulation, building the additional power storage retrieval distribution system etc) with the ability to sustain the building with low energy later on

also, James May tried to plug gym machinery to an electric car, the human output is just too low for electrical appliances - think not laptops, but washing machines, vacuum cleaners etc.

Once you get past the point of "energy I would have expended anyway for exercise/to relieve boredom" you run into the fact that humans just aren't a very good way of converting resources (food and the energy/minerals needed to grow it) into mechanical energy.

The modern food system is woefully inefficient at converting primary energy into food calories and the human body isn't all that great at it converting food into mechanical work. Useful amounts of heat are even more elusive. Toasting a slice of bread might take a half hour of vigorous exercise.

I'm pretty sure it would take more energy to heat a jacuzzi than one could extract from a dozen people showing off in front of it.

What this misses is that we don't really have any way of "generating" power aside from nuclear reactions.

It's all converting from one form to another. In the case of "human power" it's extracting energy from plants and animals that we kill.

Wait but Why has an excellent deep dive on this: http://waitbutwhy.com/2015/06/how-tesla-will-change-your-lif...

from the perspective of an engineer this is stupid. humans can not generate anywhere near the power we consume currently. if you want to experience life as a 5th century serf go ahead

You can motivate people to do manual labor a lot of ways, but this does not mean they will like it. Fear of death is a good motivator. "Hey, let's have fun working out!" is not a good motivator.

On top of this, the premise is crazy. They want to have two societies: one that produces technology with non-human-generated power so the other society can use that technology to live on human-generated power.

One of the more thought-provoking articles I've read in a long time.

If you think they're dreaming, I suggest reading it nor for engineering detail, but to try out their perspective. Most people would answer 'no,' leave it at that, and not reach some interesting perspectives they did.

Not that it goes into engineering detail, but for the creativity, thoughtfulness, and, most importantly, change in perspective from the predominant views of: we must produce more power! ... we must not change our way of looking at things!

I use my rowing machine regularly, which creates resistance through a fan and wind resistance. If it used a generator, I could power most of my apartment's electrical needs. Maybe not my refrigerator, which I shouldn't use when it's cold outside. Most of my electrical bill is fixed costs and taxes, not my electrical use, so a little less power and I could drop my contract. Articles like this one get me thinking that way.

If you keep extending how little you can use and what the world would be like if we had to work for our power instead of lazily flicking a switch and not caring about externalities, it's very interesting. Not to mention what it would do to our declining physical fitness, growing obesity, increasing disconnect from nature, and probably mental fitness too.

I bought a hand-powered washing machine a while ago and it did the job fine until it broke. Sadly, our culture doesn't promote great solutions that reduce consumption. I'd be happy to wash my clothes under my own power and other things like that if well-built ones were available. I can solve some things myself, but it's a lot easier when solutions are on sale. There are thousands of options for plug-in washing machines and only one or two hand or foot powered.

I'd love to see people engineer solutions that work and endure. This article isn't trying to solve all global power problems, but I bet its authors feel something like Stallman when he started writing GNU utilities, which people probably saw as tilting at windmills. Or even Torvalds writing the kernel, though Stallman's platform made his project more plausible to help. By the time people started Wikipedia, they could look back and build on several successful models. Or maybe like Feynman considering how much room there was at the bottom. Contemporaries probably said they were crazy and didn't see the point.

I, for one, support people thinking along these lines and seeing how far they can take us -- beyond engineering solutions to new ways of thinking about ourselves in the context of nature. I bet a lot further than most of us suspect.

if you keep extending how little you can use the answer is obviously yes, but then it isn't modern society. you could.more efficiently harness the sun than growomg plants and eating them then working out anyway, so this whole approach fails to make sense at any level.

How much energy would that same human provide when dried, burned and used as heat energy to power a turbine?

I mean, I ask for no other reason than curiosity.

About 70 kWh.


(Hey, you're the one that asked)

There truly is an XKCD for everything


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