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Latest "Green" Power Generation — Your Feet
gbjbaanb writes "Remember those ideas that suggested hooking gym machines to the power grid? Well, the Times is reporting that something like this to harness free energy is about to become a reality — the footfall of trudging shoppers is to become the latest source of emission-free energy.
'Engineers who have modelled the effects of the technology at Victoria Underground station in central London have calculated that the 34,000 travellers passing through every hour could power 6,500 lightbulbs. ... The plans for heel-strike generation follow successful trials last year at a bridge in the Midlands where generators converted energy from trains passing above into electricity powering a flood detector.'
Possibly the most important thing for the readership is at the end:
'There could also be a range of domestic uses, for example powering iPods by plugging them into batteries placed in the owners' heels, using technology which is already available.' Obviously you'd have to get up and walk around, but, as they say, it's the thought that counts."
Exactly. This article completely ignores the most interesting question -- is it cheaper or more expensive than other zero-emissions sources of energy, like solar? In some specialized applications, human power is nice. But in a supermarket or train station, power is readily available, and this should be compared on even footing in terms of $ per watt of generation capability against other options. Somehow I doubt it beats out solar power. Sure, it may be (*) cleaner than fossil fuels, but what's the point if it costs more than solar?
* Depends whether you count the marginal fossil fuel cost of food calories, which are a very expensive form of energy by the time they reach your plate. There are reasonable arguments both ways.
I would think that piezo-electric mats that absorb sound would create more energy while at the same time reducing the amount of noise would be more practical than collecting potential energy from passing trains.
Vintage computer adverts: http://www.vintageadbrowser.com/computers-and-software-ads
Yes, hence why they're using footfalls in subway lines instead of gyms. The gym analogy was just meant as to describe the "humans produce a lot of wasted energy, why don't we harvest some?" sentiment.
This sounds as practical as trying to harness the 'incredible power' of our stomach acid for energy generation. I'm sure we could power a lot of lightbulbs in a lot of ways - but I think there are better options than relying on extracted energy from human movement. It's like relying on whale and pig fat as a major power source - it just doesn't scale past a small market segment.
What we want is to use something more scalable, like algae-based oils, using arid and other unfarmable land, and not using fresh water sources for production. That, plus increases in solar power efficiency are much more direct ways of gathering usable energy, which could scale far beyond our current needs in a sustainable way. That way, we raise the standard of living of people by increasing energy production, rather than make them stick battery chargers on their feet.
Ultimately, food and fresh water will be bigger concerns going forward - and I don't think we'll be able to grow sustainable crops in our shoes with any toys either.
Ryan Fenton
My son's pc is on an old Singer Sewing Table, complete with the forged Iron foot pump affair that used to run the sewing machine.
At the moment all he does is operate the flywheel while he plays (a little noisy, but better for his legs then just sitting static for ages). I want to set it up with a generator so we can use it to power something, or store the charge in a battery.
Not perhaps the most efficient means of power generation, but a teensy bit cool.
A learning experience is one of those things that say, 'You know that thing you just did? Don't do that.' - D. Adams
Um... in this case, I don't think sunshine is something you can count on. This is true of many places.
In the United Kingdom the frequency of rain driven into the
country by the south-western trade winds following the warm gulfstream
currents. Areas along the western coasts can receive between 1016 mm
(40 inches, at sea-level) and 2540 mm (100 inches, on the mountains) of
rain per year.
I live in the middle of a temperate rainforest right here in Washington state. Solar panels simply would not work very efficiently here either.
Now, if someone wants to put some turbines in my downspouts, I think we've got a plan. But if I buy them, I expect a yearly gutter cleaning to be part of my contract.
But I digress too, to your point. This seems like it would be a maintenance nightmare. And is probably the worst of the parasitic power ideas I've heard to date.
Why can't we go back to using jumpers to configure slot adapter cards? Why? I say!
Take a door in a public place. There's a hydraulic mechanism to make sure it doesn't slam shut. There's a bit of a resistance when you open a door. Think of how many times doors in public places open & close on a given day. Sure, it may not be much per 1 door open/shut, but imagine a shopping mall or office with hundreds of doors.
Take the hydraulic damper and turn it into a generator. Chain together all the doors and have it provide power peak power hours(when the public will be using them). Make them compatible(ie mount-wise) with existing dampers & retrofit them everywhere.
Slap a generator on those revolving doors too. Imagine the power it could make in a busy downtown area.
Dang, I should patent this before.........
Given than a human muscular efficiency is considerably less than most combustion-based engines, and considering the energetic cost of producing then delivering the food in the first place is itself steep, I expect the net energy gain to be gruesomely negative. Most corn-based biofuel plants in the US fail to "get even" right now: this is an even worse bet.
W=f*d
In the case of the shoes, work done compressing the cushion approximately come back on the up-stroke. It's fairly conservative (in the physics sense). You'll find that if the shoes had tiny holes in the cushions, it'd be quite a bit harder to walk in them, especially if they had a lot of vertical play. The difference between a spring and a shock absorber.
Can you be Even More Awesome?!
Well the release of humans' methane, however, happens at much more predictable and organized locations, when compared to livestocks. So the collection and recycling should be easy. Now if only I have a permit and £500,000 to build a special lavatory at Victoria Underground...
It would be nice and all, but if all these people are helping generate the power, how is it being used/sold/distributed? Do they get a discount of tickets/merchandise? Is it required that the power gets freely distributed in some manner? If they are making money off of it (as they no doubt will want to, even if it's only to conserve their own electric bills), I want to be compensated in some fashion.
I will shred my adversaries. Pull their eyes out just enough to turn them towards their mewing, mutilated faces. Illyria
This was brought up in the media last year from the folks at MIT: http://archive.uwire.com/2007/09/11/mit-students-take-step-toward-cleaner-greener-urban-energy/ In fact, I could have sworn I saw the story run here on Slashdot. Can't we just reference the arguments from then so we don't have to rehash them?
It seems that stepping on a tile with pads which push fluid through turbines would have kind of a gel effect or feeling to the people walking on them. This could reduce the impact on the joints and perhaps the fatigue of walking around.
Here's something I've been wondering ever since I found out my body could generate peaks of 400 Watts at the gym. Is human energy really green?
My analogy to the broken window fallacy is based on the fact that this fallacy relies on what we see (the store owner buying services from the glazier) versus what we don't see (the store owner not investing that money for better purposes). Note that the logic also holds for alternative energies such as electric cars (which electricity comes from coal power) or ethanol which has to be processed/transported in a polluting way. So how green is human power? Considered that what powers us is food, we have to look at how much energy is involved in the making (making that cow live, eat and die involves making its food, transportation, etc..), the transformation and the transportation (a lot of the food you eat has travelled thousands of miles). Also it's important to note that just because it's necessary for us to eat food anyways, it doesn't make our energy free. You'll need more food if you produce 100 Watts for 30 minutes (say, if you're jogging) than if you just lay there.
Unfortunately I'm not qualified to estimate how polluting human power actually is, but I'm sure it's far less greener and more expensive than most people would assume. I think it's just yet another of these "feel good" measures that are actually not that good at all. When will we realise that there's no problem that can't be fixed by throwing a few trillion dollars into nuclear power and r&d?
You just got troll'd!