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A $5 Lamp Powered Solely by Gravity

by TannerLD on 12/21/12, 7:21 PM with 88 comments

• by ColinWright on 12/21/12, 7:24 PM

  Previously submitted and seriously doubted:

  http://news.ycombinator.com/item?id=4889266

  In that thread[0] revelation[1] said:

      At perfect efficiency, this seems to give you about
      55mW for a hour, if I asked Wolfram correctly (for
      20kg lifted one meter) - [2] - So probably a hoax.
  

  [0] http://news.ycombinator.com/item?id=4889426

  [1] http://news.ycombinator.com/user?id=revelation

  [2] http://www.wolframalpha.com/input/?i=20+kilogram%E2%80%90for...

• by dsl on 12/21/12, 7:49 PM

  Not to nitpick, bit it's not powered by gravity, it is powered by people going over every 30 minutes and lifting a weight back up to its top position.

  EDIT: Apparently people don't understand that using gravity to generate energy is a thing, and the title "Powered Solely" suggested someone found a way to do that.

• by Lagged2Death on 12/21/12, 8:11 PM

  Some people get excited by F1 racing, the Bugatti Veyron, or stuff like the latest iPhone, telling you they are technology enthusiasts or engineering fans.

  But if you ask me, it's always at the low end of things - like this project - where the really inventive, exciting engineering happening.

  Sure, something like an F1 car is impressive after a fashion, but considering the price, yeah, well, it better knock my damn socks off or it just looks stupid. Unlimited budgets do not make for impressive engineering, really.

  Making something that is truly, spectacularly useful like this for $5 ot $10? That is genuinely impressive.

• by NathanKP on 12/21/12, 8:49 PM

  Maybe I'm stupid for asking but what is the advantage of this over a spring powered wound clock? My wristwatch can tick for two days on a wind, and while it isn't as cheap as this gravity powered wound clock I'm sure it could be made cheaper. There is nothing special about this invention; purely mechanical "gravity powered" clocks have existed for centuries in the form of old grandfather clocks etc.

• by joeyh on 12/21/12, 9:01 PM

  I use kerosene lights by choice in the winter in weeks like this one when there is no sunshine. So, here's my firstish world problems take on it. May not apply to people for whom a gallon of kerosine is a significant fraction of their monthly income.

  I have a hard time seeing myself using something like this, except as task lighting. I'd be fine to have to lift a weight if I was only going to be using the kitchen for 30 minutes (it could even serve as a useful timer), or similar. But getting up every 30 minutes rules out using it anywhere I need longer duration light for eg, reading.

  Also, anywhere I could use this, I could use any of the many inexpensive crank LED lamps available everywhere, which run for similar amounts of time.

  The pity is that, with the right design, this could support a longer cord for a further lift distance, so it'd run an hour. Or multiple weights used in sequence or parallel so it can be primed for even longer (iirc that's how my grandparent's cuckoo clock worked). From what I can see, it's not designed to be very hackable, and something like this needs hackability.

  The LED light is the other problem with it; I'd much rather have a well ventilated kerosine light than blue tinged LED for almost any task. (I'm curious to see studies about kerosine health risks however.) Since this light cannot be moved, it has to illuminate the whole area, and its light doesn't seem up to it, so I'd be doubtful about eg, reading by it either.

• by obilgic on 12/21/12, 8:13 PM

  First thing I thought when I saw the title was: Linux, apache, mysql, php...

• by degobah on 12/21/12, 7:49 PM

  Technically powered by the effort of lifting it.

• by jstsch on 12/21/12, 8:57 PM

  Similar in concept to the Waka Waka light, except that's powered by a solar panel (and some quite nifty electronics):

  http://www.wakawakalight.com/

• by eliben on 12/21/12, 10:10 PM

  As always, the devil is in the details here. Does this lamp produce enough light for a family to be motivated to actually lift it every N minutes (e.g. does it produce enough light to read comfortably, or to cook a meal)? Is it durable enough to survive in essentially outdoors conditions in terms of heat and humidity? If the answers to these questions are positive, it's certainly a great invention. If not, back to the drawing board.

• by antidoh on 12/22/12, 5:04 PM

  As we all argue over whether this is powered by gravity, or food, or nuclear fusion, somewhere in a dark hut someone is lifting a weight to attend to the baby that just woke up in the middle of the night.

• by praveenhm on 12/22/12, 1:50 AM

  This is not a new idea. Cuckoo clocks, which is common in germany, works without a battery. we need to pull up the weights everyday.

• by tessellated on 12/22/12, 1:12 PM

  I don't seem to be in the target audience but the first question that came up is: How much noise does it make?

• by cr1st1an on 12/21/12, 10:38 PM

  I don't quite understand HOW does it turn the weight into energy. Could someone enlighten me?

• by lttlrck on 12/22/12, 3:13 PM

  It's not powered 'solely by gravity'

  It's powered by a human lifting the weight.

• by bobowzki on 12/22/12, 10:39 AM

  If it's real, I wonder if the gears are noisy...

• by chrisringrose on 12/22/12, 12:06 AM

  Pretty cool idea.