Google starts its energy push with designing better servers, which typically waste a third of the energy they consume before any of it reaches the components. The company uses highly efficient power supplies for the servers and efficient voltage regulators on the motherboards. It said it also strips out components that it doesn't need, like graphics chips, and designs computers and server racks to use as little fan power as possible.
The company says it saves US$30 and 500kWh per year for each server, and puts 300kg less carbon dioxide into the atmosphere.
For its data centers it focused on cooling, which can account for up to 70 percent of the overhead in energy use. It uses water evaporation to minimize the use of its chiller equipment, which is basically a large air conditioner for the data center. It showed a photograph of a large cooling tower in Oregon that it uses for water evaporation.
"With cooling towers, our data centers spend most of their time running in a mode called 'free cooling.' This means the chillers are off. Free cooling isn't technically free, but it is really inexpensive and really efficient," the company said.
The company is also using recycled water for its cooling to relieve the strain on the environment. A data center it is building in Belgium will use only recycled water, pulled from a nearby canal and run through a filtration system. By 2010 it hopes that 80 percent of all the water it uses will be recycled.
"Sustainability is good for the environment, but it makes good business sense too," the company said. "Most of our work is focused on saving resources such as electricity and water, and more often than not, we find that these actions lead to reduced operating costs."