Computers

Technology

Computers, used everywhere, have become the keystone of all working activities, from calculations to farming!

Early electronic computers were the size of a large room, consuming as much power as several hundred modern personal computers (85-100 W for a typical one). Notebooks, on the other hand, consume as little as 15 W and do not require the use of an Uninterruptible Power Supply (UPS), thanks to batteries.

Enhancements

Think clients are one way of sharing power: each user is connected through the simplest interface to a central server that provides calculation power and data storage. Computers acting as a minimal interface to the web could be the next stage: as internet aims to provide word-processing, spreadsheet and collaborative tools, they should be almost sufficient for any office purpose.

Improving efficiency of computer parts is another path to low energy consumption, through miniaturization and better assembling. Low power modes and advanced power managers (like ACPI) enhance electrical use during absence periods. Most people indeed do not like to turn off their computers, because they have to re-open any needed document in the morning, which takes time.

Future

Despite the ongoing trend of increasing frequency and computing power (for instance, quad-core CPUs will be launched soon,) manufacturers are becoming aware of lower computer consumption issues.

Powerful computers consuming 20 W or less are on their way, and LED technology for display purposes should contribute to this evolution. The graph below shows the energy efficiency improvement in computers.

Left to right

• ENIAC, one of the first ‘computers’, was weighting 30 tons and consuming 150 kW
• Multi-station system requiring only a computer for 10 users (source: Userful Desktop Multiplier)
• The OLPC (One Laptop Per Child) designed for the emerging world, should be supplied with a hand crank
• Linutop, a small ‘computer’ running from an usb key, that acts as the simplest web interface