Harnessing the Power of Sitting Down at a Desk. Seriously.

July 2nd, 2012 by Joshua S Hill

“Human nature is above all things lazy,” said Harriet Beecher Stowes, and that was the catalyst behind Swedish design student Eddi Törnberg’s “Unplugged” desk.

I sit at a desk all day, every day, writing. Needless to say, it would be nice to switch up what that means, and Törnberg’s design is all about switching up. Instead of trying to revolutionise the way humanity works — which, we have to acknowledge, is very sedentary — Törnberg has designed a desk that fits in with our current way of life, and still produces energy from that existence.

The “Unplugged” desk generates energy using three different techniques:

So-called piezo-elements are woven into the carpet, which means that whoever walks on the carpet [exposes] the crystal in the elements to mechanical stress and the elements then emit energy.

The flower is a plant-microbial fuel cell, which means that the natural sugars and enzymes help to extract energy through photosynthesis.

The seat of the chair is based on the Seebeck effect, which means that the metal on the upper surface becomes warm, in this case from the body heat, while the underside is kept cold by metal fins. The difference between these temperatures emits energy.

Source: Eddi Tornberg (.se)

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Tags: desk, energy producing desk, invention, piezo-elements, plant-microbial fuel cell, power generation, Seebeck Effect, unplugged

About the Author

Joshua S Hill I'm a Christian, a nerd, a geek, and I believe that we're pretty quickly directing planet-Earth into hell in a handbasket! I also write for Fantasy Book Review (.co.uk), and can be found writing articles for a variety of other sites. Check me out at about.me for more.

John Smith

This is pure fantasy.
Created by a design student. It looks
like an Ikea desk and pot plant plus a silly daydream.

A negligible amount of energy is dissipated from walking on
a carpet, and for this reason the piezo fibres would not be able to generate much
power, even if they were to exist.

When a usable ‘plant-microbial fuel cell’ exists, we can
discuss how much energy it can capture from indoor ambient light. I’m guessing less than a PV cell. That’s because photosynthesis reactions are fine
for capturing electrons for slowly building plant material, but are not as good
as semiconductors at outputting electricity (and there’s a reason why we put these
on roofs).

The Seebeck effect creates a voltage proportional to temperature
difference. The difference between body
temperature and ambient is small, less than about 20C, so negligible power can
be generated. If thermal energy could be
extracted, it would make the seat feel very cold.

And before energy can be captured from the heat of the
electronics on the desk (see http://www.edditornberg.se)
something has to power the electronics. Something
other than perpetual motion.

Before hypothesizing energy harvesting, check how much energy
there actually is in the environment that can be captured. Do the arithmetic. Think about it.

Please don’t just label a carpet, pot plant, chair and desk as
magic energy generators and imagine that our problems are solved.
- Bob_Wallace
  
  Wonder what the carbon footprint is for growing food -> human energy production -> harvesting butt heat?
  - John Smith
    
    As the thermodynamic efficiency of the last step is close to
    zero, and the other two steps are not too good either, I’d estimate that its carbon footprint approaches
    infinity!
    
    Low-grade heat is the devil for harvesting energy, and that’s
    not through lack of trying.
    
    Seebert devices are spec’ed in miilivolts or microvolts per
    degree, and 20C goes nowhere. A 300
    degree temperature difference is needed to do something useful. Still not much power in them though. That’s got to come from somewhere.
    
    If it worked, it would be like sitting on a block of ice.
    
    Just be thankful he didn’t put a biogas generator in the
    seat!
    - Bob_Wallace
      
      A biogas generator in the seat.
      
      Look for someone to patent that idea….
      - John Smith
        
        Too late. It’s been disclosed.