When it first caught public attention in 1994, Trevor Baylis's windup radio seemed the perfect solution for poor people in electricity-deprived countries where few can afford pricey batteries.
Twenty seconds of cranking the fold-out arm of the shoebox-size radio stored enough energy for an hour of listening. In rural areas, especially, where any sort of media are hard to come by, cheap radios would make a big difference by spreading basic information on everything from elections to health.
Unfortunately, the $79 price of the "people-powered" radio that Mr. Baylis invented in his London potting shed proved too high. That's close to a year's wages in Mozambique, for example. But new technology has reduced the price to $29, enabling the radio to reach its intended market.
Embarrassingly, the first market for products powered by Baylis's "Freeplay" technology turned out to be more the leisure crowd of the industrial world. Radios and flashlights in cottages and boats need never run out of steam, and Freeplay appliances are the answer to power-outages in hurricane belts.
These gadgets appeal because they are more eco-friendly than using batteries, and are made by ex-prisoners, battered women, and the handicapped in South Africa, who own a stake in the manufacturing end of the business.
BayGen Power Group, an R&D company that is developing Baylis's invention into an array of products, has cut the size of its 5-1/2 pound radios to less than 2-1/4 pounds. The price reduction is also impressive: BayGen executive Rob Packham expects the less-jazzy version of the new radio, destined for Africa, Asia, and Latin America, to sell for $29.
"At $29, it's within the reach of individuals in some, although not all developing countries," Mr. Packham says.
The company improved the technology by using new radio circuits that require just one-third the power normally needed for radio play - and by using thinner steel to make the windup coil, which remains 27 feet long but is now smaller than a roll of film.
Freeplay products continue to appeal in the developed world as well: The new lighter radio debuted at the Consumer Electronics Show in Las Vegas last week.
The range of applications for windup technology is growing thanks to the decreasing energy requirements for each new generation of electronic equipment arriving on the market.
Both developed and developing nations could benefit from BayGen's emerging line of human-powered generators for everything from computers and cell phones to land-mine detectors. The UN's World Health Organization is currently testing a BayGen product that uses a windup generator to convert salt to chlorine in a simple, inexpensive water-purification system.
The company is working with General Electric, one of its investors, to replace the 27-foot-long spring. In the future, "we will convert the manual wind directly into electricity that can be stored" in a rechargeable battery, says Packham.
Another investor, the South African insurance firm Liberty Life Association, brought the company's manufacturing arm to South Africa and ensured jobs went to disadvantaged groups. About 1.5 million Freeplay radios and flashlights have been sold around the world since 1994, 300,000 of them to aid agencies.