People typically go to gyms to burn off calories they should not have consumed in the first place. Or they seek to put on lean muscle, an undertaking which also burns lots of calories in the process.
From a green perspective, neither proposition is very efficient when you consider all the human energy that simply vanishes (OK, so it’s actually converted to kinetic energy and heat) during exercise. But wouldn’t it be cool if you could make electrons while on the elliptical trainer, and send them to a battery? Or if spinning could spin a turbine that produced useful electric power? If you can do it on a dance floor, why not at the gym as well?
Stop dreaming, because so-called human powered gyms are putting this very concept to the test. For fitness buffs who also possess a serious green streak, it’s an idea that’s been a long time coming. While still an uncommon sight, fitness facilities that run at least partially on human power are growing in number. We looked up a few of these true “powerhouse” gyms to discover just what a visitor might expect, besides an eager personal trainer with a clipboard and a contract.
Green Microgym, Portland, Oregon. Claiming to be the first human-powered gym in the United States, this eco-friendly fitness center was the brainchild of school teacher-turned gym owner Adam Boesel. The already super-efficient gym derives more than a third of its electricity needs from human – and solar – power, which combined save 37,000 kilowatt-hours annually (the typical utility customer in the United States consumes about 11,000 kilowatt-hours annually).
California Fitness, Hong Kong. It may not seem right to utter the words “mega-gym” and “sustainability” in the same sentence, but Hong Kong fitness chain California Fitness was one of the earliest fitness centers to install human activity-charged exercise equipment. As early as 2007, this chain had installed its “Powered by You” cross-trainer machines and stair-steppers that powered individual light fixtures and stored excess human energy in a battery.
University of California, Berkeley. It should come as no surprise that California, which helped give birth to the modern fitness culture several decades ago, also stands at the frontier of people-powered fitness machinery. As a research project, mechanical engineering students have been using a campus fitness facility as a testbed for designing and monitoring people-powered equipment. Having designed retrofit generator hookups for exercise bikes and elliptical trainers, the project team has now taken aim at developing a recumbent bike kiosk that can power a laptop.
(ReRev, a company that retrofits existing exercising machines to return electricity, has units installed at colleges across the United States.)
The Great Outdoor Gym Company, Hull, England. The confines of a gym can be great when it’s too hot, too cold, or generally lousy weather outside. The rest of the time, those walls create an unnatural barrier between you and the fresh air of outdoors. The Great Outdoor Gym Company, as its name implies, attempts to amp up your workouts by letting them take place in the sunshine. As an added bonus, the equipment lets you feed the output of your exertions into the site’s numerous electrical fixtures – including nighttime lights and a large display board that shows the amount of people power generated.
Compared to other machines, we humans are pretty weak: we can generate about 50 watt-hours per half-hour of cycling at a moderate pace. That’s about enough to keep an efficient light bulb illuminated for an hour.
These power-generating exercise machines may not provide a great deal of juice, per person, but even recovering a small amount helps. Multiplied by several gym members, those small electricity savings can over time add up to big bucks … and carbon emissions avoided. Furthermore, if people realize just how much effort goes into something as simple as powering a light bulb, perhaps they’ll be more inclined to conserve electricity at home, when they’re not in human dynamo mode.