Advanced Invention

Will the Japanese be the first to elevate to space?

One of the most promising technologies for the aspiring outer-space commuter is the space elevator. The concept, like quite a few others, was pressed into the public imagination by Arthur C. Clarke, who in his 1979 novel The Fountains of Paradise described a incredibly thin, incredibly strong carbon filament with one end anchored on Earth and the other extending up to a satellite in geostationary orbit. Now, a group of Japanese scientists are convinced that they can build a space elevator more quickly and cheaply than has been believed possible.

Who knew that providing energy and water for all could be a matter of foot cranks and dirt power?

A garden hose, a tin can, duct tape, metal piping, kitchen cleaner, and gasoline: That is all television icon MacGyver needed to make a flame-thrower to ward off a swarm of killer ants. In the real world, technologies that are affordable and practical are not so simple to create, but they can make a huge impact on people’s lives. Instead of calling on complex solutions (reliant on engines and imported resources) for low-tech problems (such as cooking and lighting), some researchers are now developing what they call "confluent" technologies—ones that are effective, affordable, and sustainable for use in the developing world. Here’s a look at the latest breakthroughs:

1  Energy in a Bucket of Dirt
Who needs nickel cadmium batteries or coal plants for electricity when you have soil? A Harvard team of faculty and African students have tapped into soil-dwelling microbes in order to provide electricity for families in Tanzania. When the microbes found in the soil digest organic materials, they naturally produce a small current, which can be harnessed with a simple device consisting of two electrodes and a small circuit board. One trash-barrel-sized unit filled with soil can produce enough electricity to light two bedrooms for a decade or more, says Harvard biology professor Peter Girguis. While each unit currently costs about $50, the team is testing new materials that would drive the price down to $7.

2  Micro-Hydroelectric Power
Hilly land streaked with small streams makes an ideal spot for micro-hydroelectric power generators, each of which requires a meager water flow of just three gallons per second to turn. (To put this in perspective, the Mississippi’s average flow at New Orleans is about 4.4 million gallons per second.) The Appropriate Infrastructure Development Group (AIDG) has helped to build three systems in Guatemala, and more communities are now saving up money for local installations.

Swifter suits, shoes that lean and gaming the pistol are just the beginning of the tech innovations giving track the runaround this summer

Every four years, we watch. We marvel at badminton, wonder about the modern decathlon and proudly pause for synchronized swimming. With more than 300 gold medals awarded across 37 disciplines, the next two weeks of our lives should be impressively unproductive. To aid in your immersion, we continue with our new series: “know your Olympic sport.” It’s part reminder that people actually get medals for this stuff (see: trampoline gymnastics) and part introduction to the science behind the sports.

The Pentagon investigates the use of a new type of airless tire designed to get troop-carrying Humvees through hot spots without stopping

In Iraq and elsewhere, improvised explosive devices (IEDs) pack a double-deadly whammy: They can kill when they explode, and then they turn surviving soldiers into sitting ducks when Humvee tires blow out. Conventional Humvee tires need a certain amount of air pressure, but also may include so-called “run-flat” inserts that wrap around the tire’s rim to keep it from going completely flat when the tire’s surface is ruptured. The U.S. Army, however, is looking for an alternative that can keep its vehicles running faster and farther than a run-flat donut after an attack.

Plans are afoot to reuse spent reactor fuel in the U.S. But the advantages of the scheme pale in comparison with its dangers

• Spent nuclear fuel contains plutonium, which can be extracted and used in new fuel.
• To reduce the amount of long-lived radioactive waste, the U.S. Department of Energy has proposed reprocessing spent fuel in this way and then “burning” the plutonium in special reactors.
• But reprocessing is very expensive. Also, spent fuel emits lethal radiation, whereas separated plutonium can be handled easily. So reprocessing invites the possibility that terrorists might steal plutonium and construct an atom bomb.
• The author argues against reprocessing and for storing the waste in casks until an underground repository is ready.