|Using steam to cool computers|
By Michael Kanellos, CNET News.com
Wednesday, March 21 2007 11:35 AM
You can hold Celsia's new cooling component for about three seconds. Then your fingers start to feel as if they're getting burned.
It's part of a new line of components from the San Jose, Calif.-based company that it says will cool off torrid hotspots inside computers and light fixtures running light emitting diodes (LEDs) better than conventional heat pipes or fans.
Feeling is believing. In the corporate demonstration, a person stirs a cup of hot water with a stick of copper. It takes about five seconds or so to feel a gradual warming sensation. The human guinea pig then stirs with one of the company's heat spreaders: the rapid rise in temperature is noticeable before two seconds elapse. Holding the NanoSpreader for five seconds is nearly impossible.
The sudden rush of heat occurs because steam is being created inside the NanoSpreader, said George Meyer, director of development at the company, which was re-launched in 2006. The exterior of the device is a copper sleeve that absorbs heat from a processor or a hard drive.
The interior consists of a series of vacuum-sealed chambers and channels containing small amounts of water. The water turns to steam, which then conducts the heat from the source to another component, such as an aluminum heat sink, that can dissipate the heat into the ambient atmosphere.
"Steam conducts heat better than almost any substance out there," he said.
Testers often don't believe that. "There's got to be some sort of chemical in there," one observer said, though Meyer affirmed that the active ingredients are copper and water.
Heat is one of the primary obstacles for industrial designers and consumer electronics manufacturers these days. Consumers want small, quiet devices. Unfortunately, components like processors and hard drives generate a lot of heat and often require fans or heat pipes, tubes of metal that conduct heat away, to keep them cool.
"The digital video recorder is one of the most strenuous applications for a hard drive there is," said Meyer. Blade server manufacturers and makers of telecommunications equipment are also shopping for new components to remove heat.
The company is also targeting LED lights. Although LEDs can produce a significant amount of light per watt of power, LEDs also generate a significant amount of heat. Thus, LED arrays often need cooling components.
IBM and other companies have created water or oil-filled components for cooling internal computer components for years. But many of these devices contained relatively large amounts of water and are therefore physically large.
Shrinking the size of these components so they won't add bulk in smaller computers has been a bit of a challenge. Cooligy has developed a liquid cooling system, but it requires a mechanical pump. Other companies working on products in this market include Nanocoolers and Cool Chips. None of these companies has experienced broad adoption yet.
For its part, Celsia asserts that it has an advantage in that its components are fairly small, measuring only a few millimeters thick, and are made out of fairly basic materials. It has also teamed up with Taiwan's Yeh-Chiang Technology, one of the largest manufacturers of heat pipes.
Getting this far hasn't been easy. The company emerged from South Korea as iCurie in 2001. In 2005, a new management team was installed and an additional US$20 million in funding was raised from various sources.
Celsia's components cost more than ordinary heat pipes or cooling technologies, but fewer cooling components are needed. In the end, the company says using its components versus ordinary ones should be cost-neutral.
The smaller number of components also frees up designers.
"If you are looking at an ultralight portable, you could build it without a fan," he said.