Picking the energy of crowds
When we walk, we produce energy which disappears into the ground. Would it be possible to harvest this wasted energy? According to Discovery News, an architectural firm in the UK wants to use crowds as a source of renewable energy. So far, the company is working on various projects with several universities and expects to "finish two vibration-harvesting prototypes by December." And don't think it's a joke: controlling our indoor environments could save annually $200 billion in energy bills in the US alone. But read more...
Here are the opening paragraphs of the Discovery News article.
The tremors from passing trucks, the rumblings of speeding trains, and even the pitter-patter of little feet could soon be captured and converted into energy to light walkways and buildings.
London-based Facility Architects is working on a project called Pacesetters that aims to literally harness the pulse of a city and reuse it as a renewable energy source.
The Facility Architects web site is based on Macromedia Flash technology, which means it's hard to point you directly to a page explaining their projects. Fortunately, in "Charging up the stairs," BBC News has almost reproduced a text by architectural firm's director, Claire Price, where she gives more details on how much energy could be saved in a London railway station.
The 34,000 commuters who pass through Victoria underground station at rush hour, for example, could theoretically generate enough energy to power 6,500 LED light fittings -- energy that today is disappearing into the ground.
Below is a statement from Facility Architects about the future control of our indoor environments and how this could save annually $200 billion in the US alone (Credit: The Facility Architects)
Claire Denis also describes other efforts to save energy from our footsteps.
There's been a surge of interest over the past 10 years, driven by the search for battery-free techniques for powering wireless sensor networks, laptops and mobile phones.
The concept was pioneered by the military sector, largely bankrolled by the DARPA in the United States (Defense Advanced Research Projects Agency).
Their interest is mainly in reducing the need for soldiers to carry heavy rechargeable batteries that serve essential yet power-hungry communication devices. So they've looked at how "heel-strike" generators, powered through the pumping motion of a footstep, can be embedded within a boot heel. These devices currently achieve upwards of 3 - 6 watts of power output.
Now, let's return to Discovery News to look at the company's projects and learn how we could save energy when climbing stairs.
[The first project] is a staircase that will contain technology -- either hydraulic or piezoelectric -- in the risers to sense the kinetic energy from commuter footfalls and convert them into an electrical current. "To climb stairs you have to apply a bit more force so there may be more energy there," said Jim Hull, a professor of engineering at Hull University.
Hull hopes to develop a system that will convert at least 50 percent of the six to eight watts each person typically generates while walking. The current will be stored in a battery, which can be used to provide energy for lighting or electronic devices.
And Claire Denis said to BBC News that its company also plans a wireless system of lighting -- an LED light fitting with its own micro generator.
This unit will convert vibrations from passing trains, lorries or planes to provide continuous light without the need for wiring into the grid. This could potentially mean considerable savings by omitting the need for the costly digging and laying of cables.
And here is her conclusion: "One day when you use a staircase at a tube station, it might be a step towards saving the planet." I sure agree with her.
Sources: Tracy Staedter, Discovery News, June 26, 2006; Claire Price, for BBC News, May 24, 2006; and various web sites
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