One of Google’s greatest expenses is electricity. Well, on Tuesday, they called for vastly more efficient PC power supplies– in partnership with Intel. The power supply is often the component that consumes the most energy in current PCs.

Google says it’s increased the efficiency of power supplies from 60-70% to 90%, and the same efficiency is within reach for consumer PCs. At the Intel Developer’s Forum in San Francisco on Tuesday, Intel CTO Justin Rattner invited Google engineer Luiz Barroso on stage to call for more efficient PC power supplies. Barroso highlighted findings from a newly published Google white paper. The paper, “High-efficiency power supplies for home computers and servers,” by Google engineers Urs Holzle and Bill Weihl, states that Google has managed to increase the typical efficiency of power supplies from 60-70% to at least 90% efficiency, reducing lost energy by a factor of four.
Barroso and other Google engineers believe that home computers can be made just as efficient as Google servers. Toward that end, Google, Intel, and other partners are proposing a new power supply standard. Assuming the new power supply design gets deployed across 100 million PCs running an average of eight hours a day, Google estimates a savings of 40 billion kilowatt-hours over three years, which translates to $5 billion at current California energy rates.

The problem with today’s power supplies, according to the paper, is that they were designed to provide multiple output voltages. In 1981, chips needed this, but not today. Yet because power supply designs have not changed, power supplies continue to be over-provisioned and inefficient.

Google servers, and the new PC standard Google is proposing, use a simplified 12V power supply that generates a single voltage. When certain motherboard components require something different, the power can be modulated using voltage regulator modules.

Google estimates 85% energy efficiency can be achieved at virtually no cost, while spending about $20 more for higher quality components can lead to over 90% efficiency.