HandsOn: Computing in the dark

Compared to the hundreds of lives and billions of dollars of property lost in the catastrophe of Hurricane Katrina, it is rather petty to gripe about computer downtime. Still, Katrina-caused disruptions highlight our growing dependence on connectivity and electricity.

You know that sinking feeling — you're working on your notebook computer on an airplane, and your screen starts to go dim as your battery runs down. How much more dire would your problem become if you couldn't plug it in when the plane landed?

Perhaps it is our assumption that power will always be conveniently available that accounts for what seems like painfully slow progress in increasing battery life for notebook computers. In the past several years, hardware and operating system power-saving strategies, such as lower-voltage processors and hibernation schemes, have extended battery life more than improvements in battery technologies have.

Despite this, new notebooks with standard lithium ion batteries still can only reliably deliver two to three hours of use on a full charge. Most notebooks also come with larger, heavier extended-life batteries that promise to keep the machine running for at least another hour. This is an improvement on the previous standard battery for notebook computers — nickel hydride — but only a marginal one. Nickel hydride batteries provided 1.5 to 2.5 hours of use.

Still, nothing on the market promises to give users a full day of computing. Fortunately, a few improvements are on the horizon.

Last April, IBM and Sanyo announced they had produced a prototype of a Direct Methanol Fuel Cell battery, which works by mixing methanol with air and water. The fuel cell can provide power for up to eight hours. The downside? The prototype weighs 4.4 pounds. But the companies expect to have lighter versions ready in 2007.

Toshiba has developed prototype batteries that can be recharged about 60 times faster than lithium ion batteries, and the company said those may be available as soon as three years from now.

For example, in 1999 Compaq Computer, now a Hewlett-Packard company, was awarded a patent for a keyboard-driven power generator. The idea, which has not yet developed into a product, uses tiny magnets that are charged when users press the keys. The current generated by each keystroke goes to a charge pump that increases its voltage and then to a trickle charger, which continuously charges a battery, for the computer's battery.

Sometimes the best answers, however, are the simplest ones. The Massachusetts Institute of Technology's Media Laboratory is developing a $100 notebook computer for use in developing countries. The Linux-based machines will incorporate, among other innovations, a manual wind-up generator so that people can use them where power is not available.

It's difficult to figure out why such hand-crank generators are not already available because they are available for emergency radios and cell phones.