By Design March 2013

Bright Idea

More
Sam Armstrong

Problem: Many of the 1.4 billion people who lack electricity use kerosene lamps for lighting, despite their myriad dangers. They cause millions of severe burns each year. Kerosene fumes contribute to lung cancer. The fuel is ruinously expensive, and it’s a major carbon emitter. But oft-proposed alternatives, like solar-powered lamps, require expensive batteries.

Solution: “We reckoned, ‘Why not use gravity?’ ” says Martin Riddiford, a co-founder and director of Therefore, a London design consultancy. One of Therefore’s early prototypes involved a steel drum and a bicycle wheel; the final product, GravityLight, uses dirt and a bit of muscle power. Mount the lamp from a wall or ceiling, fill the attached fabric bag with 20 pounds of dirt, and hoist the bag up. As the bag descends, gears turn inside the lamp, generating enough light to read by for up to 30 minutes—no batteries needed. One thousand GravityLights arrive in Asia, Africa, and South America for a trial run this spring, and a model selling for less than $10 is slated to hit the market next year.

Jump to comments
Presented by

Malcolm Burnley does story research for The Atlantic.

Get Today's Top Stories in Your Inbox (preview)

What's the Number One Thing We Could Do to Improve City Life?

A group of journalists, professors, and non-profit leaders predict the future of livable, walkable cities


Elsewhere on the web

Join the Discussion

After you comment, click Post. If you’re not already logged in you will be asked to log in or register. blog comments powered by Disqus

Video

Adventures in Legal Weed

Colorado is now well into its first year as the first state to legalize recreational marijuana. How's it going? James Hamblin visits Aspen.

Video

What Makes a Story Great?

The storytellers behind House of CardsandThis American Life reflect on the creative process.

Video

Tracing Sriracha's Origin to Thailand

Ever wonder how the wildly popular hot sauce got its name? It all started in Si Racha.

Video

Where Confiscated Wildlife Ends Up

A government facility outside of Denver houses more than a million products of the illegal wildlife trade, from tigers and bears to bald eagles.

Video

Is Wine Healthy?

James Hamblin prepares to impress his date with knowledge about the health benefits of wine.

Video

The World's Largest Balloon Festival

Nine days, more than 700 balloons, and a whole lot of hot air

Writers

Up
Down

More in Technology

More back issues, Sept 1995 to present.

Just In