Apple rival Microsoft is one of the largest purchasers of green power in the U.S. The EPA recently recognized it as the third largest purchaser of green power in the U.S., buying up more than 1.1 billion kilowatt-hours of green power a year.
Microsoft has been dabbling in renewable energy for more than a decade.
In 2004, it installed what at the time was Silicon Valley's largest solar power system, which produced 480 kilowatts at peak capacity. The solar farm was composed of 2,288 tiles, and today offsets as much as 15% of Microsoft's energy needs at a five-building campus with about 1,800 workers, according to Microsoft spokesman Doug Free.
An engineer inspects solar panels in Apple's Maiden, N.C. solar power array (source: Apple)
The company is now exploring using biogas from landfills to power its facilities. Last fall, Microsoft's Global Foundation Services Group, which runs the company's cloud services and data centers, unveiled a data center that will run on biogas produced by a local Wyoming landfill and water treatment facility. The "mini-data center" will use 200 kilowatts coming from the biogas facilities, said Henretig.
But Microsoft's largest investment has been in hydroelectric energy because the company's headquarters, and 60% of its operations, is located in the Puget Sound region of Washington state.
About 46% of the energy used by Microsoft's Redmond, Wash., campus comes from hydroelectricity, and most of the power for its data center in Quincy, Wash. is from hydropower generated in the Columbia River Basin. That alone put Microsoft in the No. 3 spot on the EPA's top 50 green companies in 2012.
At the top of the list was Intel. Officials there declined to speak about Intel's renewable energy program.
The carrot and the stick
Microsoft said what really sets it apart is its carbon fee. The fee, implemented last July, is a charge-back model to business divisions that use energy that produces carbon emissions.
Microsoft's business groups were told they must build into their budgets the price of carbon emissions for the energy they use.
The business divisions pay a carbon fee for each metric ton of carbon emissions associated with the operation of data centers, software development labs, office buildings and employee air travel. The carbon fee goes into a central fund used to purchase renewable energy and carbon offsets to achieve net carbon neutrality.
The charge-back model makes the company's business divisions responsible for the cost of offsetting the carbon emissions, Henretig said.