Forgot your password?
typodupeerror
Power United Kingdom Hardware

Pavegen To Tap Pedestrians For Power In the UK 197

Posted by samzenpus
from the electric-slide dept.
An anonymous reader writes "Several years ago Laurence Kembell-Cook unveiled Pavegen floor tiles, which capture kinetic energy from footsteps and convert it to electricity. Now after two years of product testing and picking up a slew of awards across the U.K., Pavegen has received its first commercial order — to light up the new Westfield Stratford City Shopping Centre."
This discussion has been archived. No new comments can be posted.

Pavegen To Tap Pedestrians For Power In the UK

Comments Filter:
  • by niftydude (1745144) on Friday September 30, 2011 @02:26AM (#37563762)
    Energy doesn't appear out of nowhere for free.

    Walking on these floor tiles requires more energy than regular floors.
    So are they going to start paying brits for all the extra food that they need to eat in order to power these things?
    • by onion2k (203094) on Friday September 30, 2011 @02:33AM (#37563800) Homepage

      Perhaps walking on these tiles costs the same amount of energy as regular tiles, but some of the energy that is normally wasted as heat and sound is captured and turned into something useful...

      • Have you ever walked in sand?

        • A 5 millimeter flex is not even remotely comparable to walking in sand.

          • Of course not, but both require a relative amount of extra work. Sand if just a great deal more. An example that someone would surely agree takes more energy to walk on is needed. Then by extrapolation the tiles take more emery too. Albeit less.

          • by paziek (1329929)

            It is. Just look at how much 5mm is. It sounds small, but for walking its pretty annoying.

            • by DrXym (126579)
              It's clear from the photos that these stones are clearly visible (they're green with a light in a middle) so someone could choose to walk around them if they wished. Though anyone landing their foot on one is hardly going to care that their foot sunk a miniscule amount.
              • by delinear (991444)
                Indeed, some amount of flex is actually more comfortable, so long as it's not too deep. This could well be an improvement for some people over a harder alternative (particularly those who have difficulty with high impact surfaces, like the elderly).
                • by Arlet (29997)

                  On the other hand, if you're walking on regular tiles, and step on this flexing tile, without properly anticipating the different feeling, it may throw a person off-balance.

                  • without properly anticipating the different feeling, it may throw a person off-balance.

                    Your mother was a woman who worried alot, wasn't she?

          • by gandhi_2 (1108023) on Friday September 30, 2011 @05:36AM (#37564680) Homepage

            Man this kind of argument pisses me off.

            "5 isn't even remotely comparable to 1000".

            Sure it is. It is 1/200'ths as much. Plenty comparable.

            5 mm flex is not even remotely comparable to world peace, chuck norris, or boreal toads. a flexible floor IS comparable to walking in sand.

            • by mwvdlee (775178)

              It's like comparing apples and oranges.

              Apples are green.
              Oranges are orange.
              Apples are not oranges.

              There; comparison succesfully completed.

            • It's a common turn of phrase by which the writer means the comparison is meaningless due to the extreme difference in magnitude.

              If this was a troll rather than just extreme pedantry, my apologies to the rest of the /. audience for replying.
        • by AI0867 (868277) on Friday September 30, 2011 @09:23AM (#37566090)

          Actually, a softer (energy-absorbing) surface is more comfortable to walk on, provided it doesn't absorb excessive amounts.

          The plastic tracks in stadiums are softer than asphalt, which again is softer than concrete. Guess which one people like to run on best?
          Some athletes from poor countries practice on alphalt and find they run slower in a stadium. Concrete would be even faster, but it tends to wreck your knees unless you have good shoes, which, again, absorb energy.

          • by danlip (737336)

            Rubberized tracks are springy, i.e. they store a little energy and return it to you. Good shoes do the same. This surface would not - I would think it would feel mushy.

      • The Pavegen floor tiles flex a slight 5 millimeters when stepped on

        That's an extra half cm against gravity for each step - so I don't think it is energy that is normally wasted as heat and sound - that is energy that you are being forced to supply.

        • No it isn't. Every time you step, you lift your foot (more than 5mm!), move it, and then place it down. Your weight is transferred to the new tile. If anything, this is going to be better to walk over than a hard floor, because it reduces the amount of stress on your knees from the impacts on the ground. You're not moving another 5mm, you're just encountering resistance 5mm before your foot hits the real ground.
          • You have to push through that resistance. That uses more energy. As to other posts about heat/vibration/sound energy, some of that will be gathered I'm sure but that's a minuscule amount of energy.

            The extra energy may not be noticeable and may result in a more comfortable floor though, like you said. Walking on a thick carpet would probably make you use more energy than these plates and people pay extra for them.

            • You have to push through that resistance

              Have you ever even tried walking? You don't push through resistance on the ground. You place your feed above it and then your weight pushes through the resistance. The energy you put in is in lifting your foot and transferring your weight to it. You push downwards into the foot that you are stepping off, but that one will already be on the solid ground with the switch depressed.

              • by mwvdlee (775178)

                Does climbing stairs require more energy that walking on a flat surface?
                This is like climbing 5mm high stair steps.

                • by danlip (737336)

                  I don't think so. When you climb stairs you are increasing your gravitational potential energy. When walking over these tiles you are not. I think it is more like walking on a thick carpet or sand.

                  • It is like climbing 5 mm high stairs: you step off the tile you are currently standing on (which is 5 mm lower due to your weight) on to the next tile which is up at ground level, 5 mm higher.

                    When you're climbing actual stairs, you gain gravitational potential energy because you're going up, but on this contraption you sink back down 5 mm with each step, and what would have become your potential energy is now harvested to power the lights, or whatever they plug into it.

                  • The tiles are extracting 5mm worth of potential relative to the level of the floor. 5mm that the person has to climb out of to regain what was extracted to be once again level with the floor. 5mm can really add up. Especially when you're a fat, lazy, American. Assume a storey is 5m high, now assume an average human makes two strides for every meter or 10mm climbed for every meter traveled. That means after walking 500m they've climbed the equivalent of a flight of stairs. Are you really telling me tha
            • It doesn't really matter because in the end since humans are trending towards fat, lazy blobs that travel about in Wal-Mart scooters.
    • Even if that were true (instead of the tiles just using the energy already dissipated as waste heat and sound), people in developed countries consume far more energy than they expend. The remainder is stored in fat reserves or excreted as waste. That's where this would come from; it'd be an exercise opportunity.

      (Come to think of it, it would be worth a thought to install generators in gyms for the same effect.)

    • by deek (22697)

      Two thoughts come to mind:
      * This may be a good way to reduce obesity levels in society.
      * Shopping centers with supermarkets and/or food courts will make a killing.

      Rule #1 of supermarket shopping: never shop while you're hungry.

    • by Nursie (632944)

      Think of it as a public service - most tubby city workers could probably do with some more energy expenditure in their day.

      • by xaxa (988988)

        Think of it as a public service - most tubby city workers could probably do with some more energy expenditure in their day.

        People in London are, on average, thinner than the rest of the UK. Although children in London, on average, are more obese.

        Walking to and from a station, somewhere at lunchtime, and maybe somewhere after work on the way home is hardly a lot of walking, but it's more than people who drive to work and park right outside. (Conversely, city children perhaps spend less time outside, but I can't find figures for this.)

        (I'm surprised the official website [westfield.com] for the new shopping centre has "Getting Here by Car" above

    • That it requires more energy is an added upside to the tiles, it's a selling point.

      With the current health issues people have with not enough exercise and hyper-caloric diets, having these is actually a (very mild) health benefit for the people. People who are already getting enough exercise won't mind the tiny bit extra, so the only people left who will complain about this are lazy fucks.

      And I hope you're not telling everyone on slashdot that you're a lazy fuck, are you?

    • by AC-x (735297)

      So are they going to start paying brits for all the extra food that they need to eat in order to power these things

      I don't think there's any problem of people eating too little food over here, in fact it might even help with the current obesity problem...

    • by SeaFox (739806)

      So are they going to start paying brits for all the extra food that they need to eat in order to power these things?

      No, quite the opposite! It is a shopping center, after all.

      Not only will people be providing electricity to help power the area, they'll be forking over more money into the center's restaurants and food stands from working up an appetite.

    • by daem0n1x (748565)
      No, they eat too much anyway.
    • by AJH16 (940784)

      That assumes that there is no waste involved in walking. There is a lot of waste in walking. Notably you land with more force than necessary and usually your body absorbs that energy as shock. If the floor tiles absorb that instead, it actually makes it easier on you to walk on it while harnessing the waste energy. There is no free energy, but there are ways to recover waste energy and sometimes that is a mutually beneficial thing.

    • It's a small shift,just a few millimeters. That's comparable to walking in light snow. A tad more work to be sure, but I can't see most people caring as they get to feel "Green". Also, in case you hadn't read the article they seem to space the tiles fairly widely, so walking around them is an option in light traffic at least.
  • by Zouden (232738) on Friday September 30, 2011 @02:31AM (#37563790)

    I was curious how much energy these things produce:

    The Pavegen floor tiles flex a slight 5 millimeters when stepped on, capturing kinetic energy which is either stored in lithium polymer batteries beneath its surface or converted into 2.1 watts of electricity and distributed throughout surrounding lights.

    It produces 2.1 watts for how long? 1 second? 100ms? I guess it could make some LEDs flash.
    Also:

    Kembell-Cook is now in the running to win the Shell LiveWIRE Young Entrepreneur of 2011 Award which would give him 10,000 lbs to use towards his invention.

    Wow. Will his prize be in the form of a giant cartoon-style weight with "10,000 lbs" written on it? Perhaps they'll drop it on his house.

    • by N Monkey (313423)

      Also:

      Kembell-Cook is now in the running to win the Shell LiveWIRE Young Entrepreneur of 2011 Award which would give him 10,000 lbs to use towards his invention.

      Wow. Will his prize be in the form of a giant cartoon-style weight with "10,000 lbs" written on it? Perhaps they'll drop it on his house.

      You do have to wonder if that journalist has ever been outside of the US.... or maybe he was assuming that the original definition of "pound sterling" [wikimedia.org] was still in use?

    • by dutchd00d (823703) on Friday September 30, 2011 @04:52AM (#37564506) Homepage

      It produces 2.1 watts for how long? 1 second? 100ms?

      For as long as you keep walking, I guess. As long as you produce a Joule each second, you're producing 1 Watt.

      The potential energy in a gravitational field is m * g * h, so if you sink 5 mm with every step, you're producing 9.81 * 0.005 = 0.04905 Joule for every kg of body weight at each step. If you take p(ace) steps per second while walking, you're producing p * m * 0.04905 Joules per second, i.e. Watts, as long as you keep walking. So an 80 kg (~160 lbs) person who walks at 2 steps per second could theoretically (i.e. at 100% efficiency) produce 2 * 80 * 0.04905 = 7.8 Watts. So 2.1 Watts means a 30% efficiency. Doesn't seem unbelievable to me.

    • by thegarbz (1787294)

      It produces 2.1 watts for how long? 1 second? 100ms? I guess it could make some LEDs flash.

      Just as well. It needs some way of powering the light in the middle of the floor tile.

    • It produces 2.1 watts for how long? 1 second? 100ms? I guess it could make some LEDs flash.

      RTFA - it's even better than you think.

      The Pavegen floor tiles flex a slight 5 millimeters when stepped on, capturing kinetic energy which is either stored in lithium polymer batteries beneath its surface or converted into 2.1 watt-hours of electricity and distributed throughout surrounding lights. (emphasis mine)

      TFA says it produces 2.1 Watt hours for every step someone takes on the tike. Since 1 Wh is 3600 J, we can conclude it produces about 7.5 kJ at every step (according to the website)... and it takes this kinetic energy from the human shoppers.

      7.5 kJ of kinetic energy, in a human... hmmm... what are the shoppers doing? Freefalling from 500 m altitude onto those tiles? Jumping off speeding trains into the tiles?

      The problem is that 7.5 kJ of kinetic energy, for a human of

      • by omnichad (1198475)

        Perhaps the number is in aggregate for the whole installation? What would I know, I'm not reading the article.

    • by Timmmm (636430)

      2.1 watts! We could power... a few LEDs! Or... a calculator!

      Seriously, what idiot bought this?

  • "Pavegen To Tap Pedestrians For Power In the UK" I've seen this movie trilogy. It didn't end well. No, seriously, it REALLY didn't end well
  • There have been very few interesting inventions in the UK since the '80s, and when they are the authorities / marketroids / everyone are so keen to say "LOOK BRITAIN ISN'T DEAD YET!" that every so often there's a hilarious amount of hubbub surrounding nothing.

    Thatcher taught the current 30-somethings that there is no personal gain in actually producing anything (and it's still communist to do anything other than for personal gain): if you want to get rich, become a middleman. So that's where most of the int

  • WOW, that's more than four tons! But of what?

    • by Issarlk (1429361)
      Of pounds!
      • a british £1 coin weighs 9.5g (I had to look it up).

        Which is 0.02 lb which means 10000 lbs of £1 is equal to £500,000 which is a very impressive prize fund.

        £1 coin contains 70% copper, 5.5% nickel, 24,5% zinc

        Copper = $3.1640/lb = ~$0.04/coin
        Nickel = $8.3801/lb = ~$0.01/coin
        Zinc = $0.8484/lb = ~$0.005/coin
        Total ~$0.05 of material in a coin
    • Who cares? Just think of all the energy you could produce by dropping it on the tiles!
    • by Syberz (1170343)
      Feathers, it's lighter.
  • so the shopping centre can say "look at what we're doing for the environment"... completely ignoring the energy and pollution costs of making these tiles... we have one of those energy recovery plates in the entrance drive to Sainsbury's [businessgreen.com] in Gloucester... they claim the energy from the cars goes into powering the checkouts.. pure greenwash to make the customers feel slightly happier about the fact they've driven to the store... and effectively they're stealing the energy from the customers as the cars are sl
    • by jo_ham (604554)

      Did you read the article? It talks about the energy cost of making the tiles, and the recycled truck tyres that go into them among other things, as well as keeping the production facilities closer together to minimise transportation costs during construction.

    • by Sockatume (732728)

      Yeah, people always forget to factor in the energy required for manufacturing. It's important to quantify it in all "green" tech, but for energy harvesting applications it can completely outweigh the benefits.

  • Trucks are heavier than Oprah and friends.

    • I believe the problem here is the durability of the materials; (much) heavier loads and resistance to environmental factors (this walkway is in a Mall) would be much more expensive to withstand.
    • Tapping people like this can be spun as a health-benefit, exercise is widely believed to be beneficial for most people. The fact that it is inefficient is of little concern as the source is so cheap.

      Tapping cars on the other hand leads to the consumption of more fuel, increasing carbon emissions, and is basically one of the least efficient ways of generating electricity that anyone takes seriously.

  • ...you've just got to love the US-centric journalist or sub-editor who doesn't know what the UK's currency is.

    Maybe it's time to employ some people who have a little more worldly experience than the dolts they have there right now?

  • by eastlight_jim (1070084) on Friday September 30, 2011 @04:20AM (#37564346)

    Some quick back of the envelope calculations: FTFA, each tile generates "2.1 W" per step. If we assume a typical step time of 500ms based a pace of 120 steps per minute this could be interpreted as about 1.05J captured per step.

    The casing is made from stainless steel which required about 53 MJ/kg [bssa.org.uk] for production in 2004. If we assume a tile casing mass of 2kg that is 106 MJ required for the steel production alone.

    The shopping centre may be open around 10 hours a day with perhaps 20 seconds between each step averaged over a typical day. This is 1800 steps per day at 1.05J per step giving a total of 1890 J captured per day. Assuming 100% efficiency and a never-closing shopping centre, this gives an energy breakeven for the steel alone of around 56000 days or 153 years.

    I know that other factors are in play such as the potential to raise awareness of environmental issues but this is ridiculous. I noticed that the award that the guy is in the running for is sponsored by Shell and part of me suspects that they know that these things are crap but want to be seen to promote something like this which appeals to the public and appears "green".

    • by bruce_the_loon (856617) on Friday September 30, 2011 @04:39AM (#37564440) Homepage

      You also have to take into account the amount of energy taken to make the ceramic floor tile that this replaces. It probably won't zero out the stainless steel energy, but grinding clay and baking it in a kiln uses some energy.

    • You have a huge flaw in your math here:

      "This is 1800 steps per day at 1.05J per step giving a total of 1890 J captured per day."

      Wrong. Depending on what your point of measure is (you don't say really), it is either 1800 steps per day PER FILE, or 1800 steps per day PER PATRON.

      Either of these would multiple the daily output by at least thousands of times.

      • by jimicus (737525)

        If it's per-tile, it'd also multiply the energy involved in manufacturing the things.

    • by Timmmm (636430)

      You can work out the energy like this:

      The height is 5 mm. Weight is, (we'll be generous) 100 kg. So the energy is at most 5 joules per step. Generating 2.1 W therefore needs 1 step every couple of seconds, which sounds like a reasonable maximum. So even the pathetic 2.1W figure is hopelessly optimistic.

  • Unstable sidewalks to go with unstable, convex shoes to shape your butt and break your ankles! I assume these sidewalks will be right in front of hospitals and orthopaedic offices.
  • Yes, the average slashdotter can do the calculations in his head and deduce that this will not produce useful quantities of energy, but that does not make it a bad idea.

    This guy will get millions in venture capital while you guys are still slaving away at the bottom of the R&D department of some big corporation.

    And should the "green" venture capital ever run out, I'm sure he can re-brand this as a military application (power for smart landmines perhaps?) and get another billion from the ministry of defe

  • "If you take a walk I'll tax your feet".

    Prophetic words indeed

  • And that's not to the idea of the tiles, which seems to me to be great and laudable, it's a "wow" to the nit-picky posts that seem to have proliferated about "oh, they're stealing my energy from walking, who will pay for the extra effort" and such like..
    Seriously people! The body is designed to absorb shock from walking (all that cartilage in the joints and such like). Hey, to improve on that, shoes were designed to help absorb impact, and let the joints last even longer. Anyone ever thought of asking Ni

"Now this is a totally brain damaged algorithm. Gag me with a smurfette." -- P. Buhr, Computer Science 354

Working...