In The News > New Scientist:Clockwork is Making a Comeback

2001-08-09
2001-09-08
New Scientist

Clockwork is Making a Comeback
It sounds like a step backwards, a return to the sepia-tinted days of the Model T Ford and the crank-handle gramaphone. But clockwork is making a comeback. Everybody knows about wind-up radios and torches, but they're just the start. A wind-up charger for mobile phones should be on the market by the end of the year. If that takes off you could soon be cranking your Discman, MP3 player, pager, laptop computer-or any other battery-powered device you care to mention. Wind-up electricity has obvious advantages. It's free, if you don't count the cost of the energy your arm burns as it cranks the handle. And it's always there. You'll never need to buy another battery or curse yourself for forgetting to charge up your phone or laptop. More importantly, wind-up electronics has the power to transform lives. Two billion people in the developing world have no mains electricity and cannot afford batteries. Wind-up power can give them access to modern information technology. And according to the UN, that technology helps banish poverty (New scientist, 14 July, p 17). The wind-up revolution began ten years ago when British inventor Trevor Baylis saw a BBC television documentary about AIDS in rural Africa. He realised that a radio that didn't need mains electricity or batteries would help battle the ignorance that hastened the spread of the disease. So off he went to tinker in his shed. He emerged with a clockwork radio that played for 14 minutes after 30 seconds of winding. It was a beautifully simple, failsafe idea. Turning the hand crank coiled a thick steel spring from one spool to another. As the spring slowly unwound, a system of gears drove a generator that produced electricity to power the radio. All it took was a little elbow grease. Baylis's invention was aimed at Africa but it became a surprise hit in the developed world. Despite being written off as a gimmick, wind-up radios acquired a sort of "lo-fi" cool. Freeplay Energy, the company that bought Baylis's idea and turned it into a commercial product, played up to the image by making the cases out of transparent plastic so you could see the innards clunking around. People found the radios useful for camping and gardening. They put them in their bathrooms and sheds. Since 1996, Freeplay has sold more than a million wind-up radios to Western consumers. European and Japanese electronic giants quickly jumped on the bandwagon. Sony, Philips and Aiwa now sell wind-up radios. Clockwork torches soon followed, and Freeplay started talking about other windup gadgets, including CD players, mobile phones and laptop computers. But they never emerged. The problem is you only get out of a wind-up device what you put in. Crank one of the radios for a minute or sound you're rewarded with 30 minutes of play. Well worth the effort, but bear in mind that radios do not consume much power. The more power hungry the contraption, the less operating time you get for your effort. A 1-minute wind on a torch gives you just 6 minutes of light- and torches are hardly energy guzzlers. Freeplay uses light-emitting diodes that consume just 24 milliwatts. For anything much bigger, this makes wind-up technology impractical. An average laptop, for example, consumes about 35 watts. For an hour's computing time you'd need to crank in at least 126,000 joules. That's roughly equivalent to 3 vigorous minutes on an exercise bike assuming an impossible 100 percent efficient energy conversion. And nobody wants a bicycle-powered computer. Mobile phones consume about 2 watts when they're beaming information to a base station. Less demanding, but you'll still have to put in a lot of physical grind for a decent conversation. However, this problem is slowly going away. Manufacturers of mobile phones and laptop's, well aware that the battery life is the biggest bugbear for consumers, are making their devices ever more efficient. The target in computing is to reduce power consumption by a factor of ten (New Scientist, 3 March, p 32). Once that happens your 3-minute workout drops to 20 seconds or so. In other words, mainstream consumer electronics are entering the purview of wind-up power. By the end of this year you should be able to buy the first "next generation" wind-up product-a hand-cranked charger for mobile phones. Developed by Freeplay and marketed by Motorola, the unit works with any mobile phone currently on the market. Winding the palm-sized generator for 30 seconds gives you 6 minutes of talk time or 2 hours on standby. Not a lot, but enough for emergency back up. The phone charger's wind-up mechanism has been upgraded to make it lighter, smaller and more convenient then Baylis's original spring-driven unit, which stored energy in mechanical form and converted it to electricity on the fly. In place of the steel spring the Motorola charger has a dynamo, a current converter and a rechargeable lithium ion battery. The dynamo converts your elbow grease into an alternating current, the AC-to-DC converter turns that to direct current, and this is stored in the battery for later use. That means you can charge up at your convenience rather than just before you want to use it. Recent models of the Freeplay radios and torches use a similar system, as do the Aiwa, Sony and Philips radios. The charger has some obvious drawbacks. You'll have to leave your mobile plugged into the unit-it doesn't charge the battery inside the phone. You can't crank very quickly because the lithium-ion battery only recharges at a leisurely pace. The optimum input power is 8 to 10 watts, which is frustratingly sedate. Freeplay says the chargers will retail for up to £45. That's a lot more than battery powered emergency chargers, but with no outlay on batteries they eventually pay for themselves. Another British inventor is pushing wind-ups even harder. Howard Atkin, head of Atkin Design and Development in Harrogate, North Yorkshire, has prototype wind-up units to power anything from electric razors to laptops. His systems also use a hand-cranked generator, but instead of a rechargeable battery they have an energy storage device called a super capacitor. Atkin claims his set-up is more efficient than Freeplay's. To prove it he bought a radio from his local shop and modified it to draw power from one of his packs. It played for 90 minutes on a 1-minute wind. Battery Beater Super-capacitors-also called ultra-capacitors-area cross between a regular capacitor and a rechargeable battery. Like normal capacitors they store electrical charge. But their capacity is a billion times higher. That's because the electrodes are made from carbon powder, giving them a huge surface area to store charge. One big plus for wind-up applications is that supercapacitors can absorb large amounts of charge in seconds. That means you can crank away as vigorously as you like. Supercapacitors can also be charged and discharged many more times than a rechargeable battery. They cost about the same and they're more efficient, releasing 92 per cent of the energy you put in compared with 85 per cent for a nickel metal hydride battery. The downside is that supercapacitors discharge quickly, so they are good for pulses of power but not a steady stream. Atkin, however, is planning to use a new type that discharges gradually. Just about any gadget that currently uses a battery can be wound up instead, says Atkin. He aims to have radios and torches on the market by this time next year. After that will come all sorts of devices with built-in crank handles: mobile phones, personal stereos, pagers and GOS receivers. So what about wind-up computers? In 1997, in front of the conference of Commonwealth Education Ministers in Botswana, Baylis attached one of his spring generators to a small portable computer called the Apple Newton eMate 300. From 1 minute of winding he generated 14 minutes of computing power. The eMate has since been phased out but it was designed for low power consumption, which suggests a bright future. And the market is there: how many times has your laptop battery fizzled out after 2 hours even though you charged it up all night? Once wind-up gadgets make it onto the market their success is in the hands of consumers. But one day soon, people cranking furiously at their MP3 players might be a common sight. That's all well and good for Western gadget-buyers. But what of Baylis's vision for the developing world? At first glance it seems the next generation of wind-ups have been designed exclusively with rich consumers in mind. Sony, Philips and Aiwa don't sell their radios in developing countries and have no plans to do so. The Motorola phone charger will be launched in Europe and North America. And Atkin's target will be the kind of electrical boutique where he bought his prototype radio, not the street of vendors of downtown Lagos. It would be a tragedy if the wind-up revolution bypassed the developing world. "One of the greatest barriers to alleviation of poverty is information," says Kristine Pearson, executive director of the Freeplay Foundation, a development trust founded by Freeplay in 1998. "But the biggest limitation is power; it's about a regular electricity supply". Kate Raworth, co-author of this year's UN Human Development Report, agrees. She says the principal need is for wireless communications such as mobile phones. "Access to communications can have far-reaching effects on people's lives," she says. "And wind-up technology offers the possibility of moving forward without having to supply electricity to rural areas." To get some idea of the technology's potential, consider what the original Freeplay radio has done for rural Africa. In 1997, the African Centre of Meteorological Applications for Development began broadcasting weather forecasts to farmers in its native Niger. With the help of Freeplay radios it now reaches 49 countries. And after last year's floods the Freeplay Foundation distributed more than 7,000 radios to destitute people in Mozambique. A daily programme called Ndhambi broadcast information on health, hygiene, sanitation, locating landmines and contacting lost family members. Mobile phones also change lives, as the "village phone" initiative in Bangladesh has shown. Members of the Grameen Bank, which operates a bit like a credit union, can take out loans to rent a mobile, which then becomes the payphone for their village. When villagers use the phone, they pay the operator, who can then payback the loan and start making a profit. Muhammad Yunus, managing director of Grameen, says that the scheme is having a real impact on poverty. People use the phone to buy and sell goods and keep track of market prices. And the villagers can keep in touch with relatives working in the Gulf and Singapore. But electricity is a problem. Many of the 30,000 subscribers in rural Bangladesh are in the paradoxical situation of having network coverage but no mains electricity. The situation worsens s the further you move out from Dhaka. It's a common problem all over the developing world. At the moment, Yunus says, villagers use solar panels to power the phone batteries, but these are expensive, intermittent and fragile. Imagine the impact a wind-up charger would have. Yet Grameen has no plans to use wind-up electronics. And how could it, when the charger costs £45? "It is too expensive for a true developing country market, we know that," admits John Hutchinson, Freeplay's technical director. He says the company is working on a cheaper alternative, although it will take time to get the price down and the distribution network in place. The main problem is the cost of the components. Rechargeable lithium-ion batteries are expensive, and the "handshake" between the phone and the charger-the signals that they send to recognise one another so they can exchange information-requires sophisticated microelectronics. Freeplay engineers are trying to halve the cost by cutting corners in the generator. "In the developing market, you're not trying to sell it on efficiency," says Hutchinson. "People are prepared to put in more effort." Ultimately, the aid and donor communities want to get computers with Internet access into the developing world. "Our big turn-on, eventually, is that the third or fourth generation of the Internet will be wireless. That's where we want to be," says Hutchinson. And he says the best way to power these computers is with wind-up generators. "I don't know how to do it yet, but I think it's the next thing." The real problem is that there is no money to be made in developing countries, and hence no market for wind-up electronics. In Africa, Freeplay radios sell for £26 to £36, depending on the model and the size of the order. This is about half the retail price in Europe, but still beyond the means of poverty-stricken people. Freeplay has sold 170,000 radios in developing countries, but almost all have been paid for by aid organisations or government grants. Freeplay thinks the phone charger will be distributed by mobile phone companies, whose expansion plans are frustrated by the lack of mains electricity in parts of the developing world. But perhaps the best hope is that the new generation of wind-up devices catch on in Europe and North America. After all, without those million or so consumers in the developed world, Freeplay would not have been able to improve it's technology or distribute radios to needy people in Africa. The same scenario could play out with the newer technologies. So if you want a wind-up revolution, go and buy the first wind-up device you see. The gadget will pay for itself anyway, and you could be helping make life in the developing world run more smoothly than clockwork.

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