In a white paper to be presented Tuesday on the opening day of the Intel Developer Forum in San Francisco, two leading data center designers at Google will argue thatfor historical reasons, dating to the introduction of the first IBM PC in 1981.
At that time,, which convert high-voltage alternating current to low-voltage direct current, were required to provide multiple output voltage, which is no longer necessary in today's PCs.
The Google plan calls for a shift from multivoltage power supplies to a single 12-volt standard. Although voltage conversion would still take place on the PC motherboard, the simpler design of the new power supply would make it easier to.
The Google proposal is similar in its intent to an existing effort by the electric utility industry to offer computer makers financial incentives for designing more efficient power supplies for personal computers. Existing PC power supplies vary widely in efficiency, from as high as 90 percent to as low as 20 percent.
The existing effort, 80 Plus, sets an 80 percent efficiency standard as a goal. It is a partnership between Ecos Consulting, an environmental consulting firm, and a group of electric utility companies. Ecos began measuring the efficiency of computer power supplies in 2003 and found that none of them met the efficiency standard.
But a technical adviser for the utility project said in a telephone interview Monday that since the program began last year, the industry has begun to move toward more efficient designs.
"We now have 70 compliant designs from 15 to 20 manufacturers," said the adviser, Chris Calwell, vice president and director for policy and research at Ecos Consulting. The new designs are just becoming available in commercial products, he said.
Modern PC designs shift the control of voltage to the motherboards, making the multiple voltage requirements of industry standard power supplies unnecessary, wrote Urs Hölzle and William Weihl, the authors of the Google paper, "High-Efficiency Power Supplies for Home Computers and Servers."
Google executives said Monday that they were not familiar with the existing effort. They said the project was complementary with their plan and that they were trying to start an industry discussion of the issue.
The overall Google goal is to be applauded, Calwell said, but by redesigning and simplifying power supply design, he worries that it is possible that overall efficiency may not be improved significantly.
Both the Google engineers and Calwell agreed that there was a significant design flaw, which they described as "overprovisioning," in today's PC power supplies. "It's like putting a 400-horsepower engine in every car, just because some cars have to tow large trailers every once in a while," Calwell said.
The Google white paper argues that the opportunity for power savings is immense--by deploying the new power supplies in 100 million desktop PCs running eight hours a day, it will be possible to save 40 billion kilowatt-hours over three years, or more than $5 billion at California's energy rates.
Although Google does not plan to enter the personal computer market, the company is a large purchaser of microprocessors and has evolved a highly energy-efficient.
It is not the first time Google has entered into an industry debate over efficiency. At the Consumer Electronics Show in January, its co-founder, Larry Page, called on the industry to adopt a single power supply standard for portable devices.
"I'm going to just plead with all of you, let's get the power supply problems fixed, or let's get all these devices talking together," he said during a keynote address.
According to EPRI Solutions, an energy research and consulting firm, over 2.5 billion AC/DC power supplies are used in the United States and 6 billion to 10 billion worldwide.
Currently, EPRI said, power supplies account for more than 2 percent of the nation's electricity consumption and that more efficient design could cut use in half, saving nearly $3 billion in electricity costs.
One personal computer industry pioneer said he believed that the Google proposal might have important indirect benefits.
"I imagine a standard low-voltage distribution system inside buildings having alternate energy supplies like solar," said Lee Felsenstein, the designer of the Osborne 1 and Sol personal computers. "Google's proposal would make that a practicality."