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Wild Green

Former Utne Reader senior editor Keith Goetzman on environmental issues from climate change to composting.


Exercise Machines Will Not Power the World

 by Keith Goetzman


Tags: green energy, renewable energy, power, exercise, electricity generation, environment, IEEE Spectrum, Keith Goetzman,

Treadmill runner 

It seems like a brilliant green-power scheme: Capture the unharnessed energy created by people working out in health clubs. But there’s a problem with this plan, contends IEEE Spectrum’s Tom Gibson after crunching the numbers: The actual energy gains are small, especially in relation to the cost of retrofitting existing gym equipment.

Consider, for instance, how long you’d need to pedal a stationary bike to power a clothes drier for an hour, for instance: About 40 hours. You could power a coffee maker with 10 hours of riding, or a laptop computer with about 30 minutes of bike time. Ultimately, Gibson concludes, exercise-generated power wouldn’t offset much of a health club’s energy use, and its long payback time doesn’t make much economic sense either:

Gibson goes a bit overboard in his zeal to debunk the green-gym folks—did he really need to include charts showing that exercise bikes cannot in fact power the nation?—but at least he lets supporters have their say. Three U.S. companies are working to market the technology, and to defend themselves from doubters like Gibson:

Source: IEEE Spectrum 

Image by maHidoodi, licensed under Creative Commons.