Microsoft on Tuesday vowed it would be carbon neutral in the fiscal year starting July.

The plan to zero-out the overall amount of climate-changing gas spewed while running data centers, software labs, and offices and even during work-related travel included charging departments a fee for carbon produced.

"The goal is to make our business divisions responsible for the cost of offsetting their own carbon emissions," Microsoft chief operating officer Kevin Turner said in a release.

Turner added that while Microsoft is not the first company to go carbon-neutral he hoped the move would encourage other businesses to follow suit.

"It's the right thing to do," he said. "Working on the issues of energy use and environmental change provides another opportunity to make a difference in the world."

Microsoft's pledge came less than a month after activists rappelled down a Seattle office building to get the software colossus and Amazon.com to use clean energy to power datacenters running services based in the Internet "cloud."

Two Greenpeace members launched from the roof of a new headquarters being built for Amazon.com, across a street from Microsoft offices, to hang a cloud-shaped banner with a message asking the companies "How clean is you cloud?"

The stunt came on the heels of a Greenpeace report grading major technology firms on the use of renewable energy sources to meeting rocketing datacenter demands and marked the start of a Clean Our Cloud campaign.

Amazon, Apple and Twitter were graded poorly in a Greenpeace study of technology titans' use of clean energy to power the mushrooming Internet cloud, but Facebook, Google and Yahoo! won praise.

Both Amazon and Microsoft datacenters rely heavily on "dirty and dangerous coal and nuclear power," according to the report.

"Today's announcement by Microsoft to become 'carbon neutral' is a good first step" said Greenpeace senior analyst Gary Cook.

"However, the devil is in the details, and the details will show whether Microsoft becomes a transformational leader in moving us toward a clean cloud, or continues to rely on coal."

Microsoft's plan allows it to continue building data centers that rely on power from coal and then offset the pollution with renewable energy credits instead of shifting to green sources of electricity, Cook noted.