Feeds

Brit inventors' GRAVITY POWERED LIGHT ships out after just 1 year

Lift a sandbag and light up your home - all for $10

Seven Steps to Software Security

Pics The British-designed Deciwatt gravity-powered lamp is now in production and shipping, a year after the project went public.

It was conceived by Martin Riddiford and Jim Reeves of industrial design outfit Therefore, which is best known for clever mechanical designs including the Psion computer keyboard. Therefore invited The Register to see the contraption at work this week.

The GravityLight is intended to provide a less damaging and dangerous* alternative to burning kerosene or biomass in the world's poorest countries - but it has also captured the imagination of Western hobbyists.

The user fills a bag with debris – sand, rocks, whatever comes to hand – which is threaded through a proprietary electricity-generating device (see sketch below right). Each hoist of the weight provides 30 minutes of low power LED lighting. A power out socket allows other devices to be charged and GravityLights can be daisy-chained together. In keeping with its Third World target market, it costs just $10.

Riddiford and Reeves set up a venture, Deciwatt, to put the idea into practice. The unit provides just a tenth of a watt of power - hence the name. They bypassed the waffle shops of the UK innovation sector and went straight to the public for funds, initially seeking $55,000 to build prototypes. It got better. Putting the idea in front of the largely US audience of fundraiser Indiegogo, the team raised just under $400,000 from more than 6,000 pledgers. A year on, every backer who pledged over $50 is receiving a sample of the GravityLight.

What's new?

Well, the initial GravityLight was just a prototype - it wouldn't hoist more than 10kg, and it wasn't really safe to use. It broke easily. The team has also made it more compliant with safety regulations - and it now gives unmissable visual feedback if it's overloaded or tugged, by flashing red. Bearings were stripped out, and it's now a robust piece of kit, capable of holding 7.5kg to 12.5kg of weight. And it now contains gears - so you can run an LED for 30 minutes at lower power, or 15 minutes of higher power, with an intermediate setting giving 22 minutes of light.

Kits are going out to Guatemala, the Philippines and Bangladesh to gauge real user feedback. The proposition, Riddiford explained, is: do you want to save a few cents a day in fuel by lifting a weight? If people find that acceptable, then it's likely to go to the next stage. The economics, Riddiford told us, are compelling. Each hoist saves about 1 cent's worth of kerosene. Over two years this adds up to a saving of $100 - so the device pays for itself quite rapidly.

Some guinea pigs have baulked at paying the $10 upfront cost - which is understandable in markets where wages are $1 or $2 a day and credit is hard to find. This could be solved by providing the GravityLight under a hire-purchase or loan agreement; a common model in under-developed economies.

Lifting 20lbs of weight up to six feet in the air every few minutes isn't something everyone would want to do. But in poor parts of the world the standard fuel, kerosene, is a carcinogen that can cause skin damage and breathing problems.

"Cases of accidental poisoning by children are still relatively common," notes the World Health Organisation (pdf).

"When some people see [the GravityLight] they think they can light their whole house from it, forgetting that it's only a tenth of a watt," Riddiford told us. "But it's really a first step out of poverty."

Other uses for the GravityLight include charging radios or phone batteries. The battery must be removed from the phone, though. Here's where the team hopes the Indiegogo side of the experiment bears fruit - with the Western users encouraged to tinker. One official accessory, the SatLight, is already available for supporters. This distributes the power to lights around the room.

Two daisychained GravityLights powering a string of LEDs

At this stage it's all about refinement and feedback. If all goes well then real production runs will follow. The state of LED tech is constantly improving, with advances in surface mount technology, and is increasing in efficiency.

For more on the GravityLight, try the website at http://deciwatt.org. ®

* Kerosene/paraffin-related injuries including burns and paediatric poisonings run into the thousands over the course of a year in Kenya alone. In rural areas in Africa and Asia, where some parts are completely cut off from the electricity grid and whose inhabitants are poor, kerosene-triggered shack fires that kill hundreds at a time are very common, especially during the dry season.

The Power of One eBook: Top reasons to choose HP BladeSystem

More from The Register

next story
Bad back? Show some spine and stop popping paracetamol
Study finds common pain-killer doesn't reduce pain or shorten recovery
Malaysian Airlines flight MH17 claimed lives of HIV/AIDS cure scientists
Researchers, advocates, health workers among those on shot-down plane
World Solar Challenge contender claims new speed record
One charge sees Sunswift travel 500kms at over 100 km/h
SMELL YOU LATER, LOSERS – Dumbo tells rats, dogs... humans
Junk in the trunk? That's what people have
All those new '5G standards'? Here's the science they rely on
Radio professor tells us how wireless will get faster in the real world
The Sun took a day off last week and made NO sunspots
Someone needs to get that lazy star cooking again before things get cold around here
Boffins discuss AI space program at hush-hush IARPA confab
IBM, MIT, plenty of others invited to fill Uncle Sam's spy toolchest, but where's Google?
prev story

Whitepapers

Top three mobile application threats
Prevent sensitive data leakage over insecure channels or stolen mobile devices.
Implementing global e-invoicing with guaranteed legal certainty
Explaining the role local tax compliance plays in successful supply chain management and e-business and how leading global brands are addressing this.
Top 8 considerations to enable and simplify mobility
In this whitepaper learn how to successfully add mobile capabilities simply and cost effectively.
Application security programs and practises
Follow a few strategies and your organization can gain the full benefits of open source and the cloud without compromising the security of your applications.
The Essential Guide to IT Transformation
ServiceNow discusses three IT transformations that can help CIO's automate IT services to transform IT and the enterprise.