The Power of Kinetic Energy
Alternative energy has come a long way in the past 20 years. Solar energy especially has seen improvements in efficiency and costs in the last couple of years, and will continue to see more. It’s a great reminder that when a concept just makes sense, it’s worth the R&D to keep improving the technology until it can be widely adapted. It’s something we’ve seen happen with phones, computers, and now energy.
If you haven’t had the chance to make it over to the Burns &McDonnell Science City exhibit, the Science of Energy, at Kansas City’s Union Station, we highly recommend you go explore it one day. While intended for kids, the terrific thing about Science City is that at any age, you can generally learn (or relearn) something new. And have fun doing it.
Their signature component at the Science of Energy is the giant Power Wheel, which you can jump on and spin, and try to light up a sign with the power of your own human energy. A digital display tracks your speed, distance, calories burned and the watts of energy you generate.
And for those who don’t want to jump on the Power Wheel, you can also grab a seat on one of two bicycles, and pedal away to light up a light bulb. Smaller visitors can try the Electric Hand Crank Generator, spinning the crank to power a fan and small lights.
Just like electricity can be taken for granted that it’s there, I think we often forget those science class lessons about kinetic energy, and calories as measurements of energy. Which is why Science City is so great.
Paris Marathoners create power with each step
In terms of real world applications, the 37th Paris Marathon turned into a historic event this past spring when marathon organizers laid down 176 special tiles over 25 meters. As the feet of thousands of athletes pounded those tiles, they generated 4.7 kilowatt-hours of energy.
How much energy is that? 4.7 kWh of energy is enough to power a five-watt LED bulb for 940 hours – or 40 days – or enough to power a laptop for more than two days.
In comparison, a typical 25 kilowatt solar-energy system in Missouri generates approximately 33,000 kilowatt hours a year – depending on the solar irradiation in your area and other factors, like the placement of you system. That’s around 90 kilowatt hours a day (though it does vary, weather-dependent).
The tiles used at the Paris Marathon were created by London-based company, Pavagen, who says that technology like theirs can be used to easily collect power created by footsteps – one footstep that depresses the tile by five millimeters generates between one and seven watts – to power low-voltage equipment, like streetlights and vending machines.
In an article for Scientific American, Pavagen founder Laurence Kemball-Cook said, “The Paris Marathon is the first of many such projects that will enable us to realize our goal of taking this technology to retail sites, transport hubs, office blocks and infrastructure spaces.”
One could easily imagine lights in heavily trafficked public spaces being powered by that foot traffic itself. It’s almost a no-brainer. Kemball-Cook acknowledges the great promise of the technology, but also notes that implementation can be challenging, as the tiles must be highly durable, weather resistant, and – most importantly – stand up to heavy foot traffic with high fatigue resistance.
But in a couple of years, there’s a great chance you may be walking somewhere, powering your surroundings with each step you take. And that’s pretty cool.
Can you think of more applications for this technology? What about ways to collect and use kinetic energy? Please share with us in the comments section.