Note - this is talking about the PSU's that most OEMs use. Most people on the forum have PSU's with better efficiency
Google, Intel and a host of PC and component companies on Tuesday unfurled the Climate Savers Computing Initiative, an effort to increase energy efficiency in PCs.
At the heart of the initiative is a push to get PC makers and consumers to adopt more efficient power supplies and voltage regulators. These two components, working together, convert AC power from a wall socket to 12-volt DC power that a computer uses.
Roughly 50 percent of the power delivered from a wall socket to a PC never actually performs any work, according to Urs HÃ¶lzle, Google fellow and senior vice president of operations. Half the energy gets converted to heat or is dissipated in some other manner in the AC-to-DC conversion. Around 30 percent of the power delivered to the average server gets lost, he added. The power in both cases is lost before any work is accomplished by a computer: later, even more energy is lost by PCs sitting idle, or as heat dissipated by other components.
By adopting more energy-efficient components, PCs and servers can utilize 90 percent or more of the electricity delivered to them. Google's own servers, in fact, are already 90 to 93 percent efficient.
Under Climate Savers' wish list, generic PCs and servers will be at least 90 percent efficient by 2010. If that goal can be met, these power-efficient servers and PCs will save 71.6 billion kilowatts of electricity in that year, said Gelsinger. The amount of electricity saved would result in 54 million tons of carbon dioxide not being put into the air that year.