EBay plans to build a data center to handle its billions of dollars in retail transactions that will draw its power from alternative energy fuel cells rather than the national power grid, which is heavily dependent on coal plants.

It will be the first major tech company to use alternative power as a primary source for energy-hungry data centers, although the new center will connect to the electricity grid for backup. Environmental groups have issued a series of rebukes to Internet companies because of their heavy reliance on coal-fired power to run their centers.

Some companies already use alternative energy to run the data centers that power social networks, stream entertainment or manage commercial transactions, but only as a supplemental source.

EBay plans to use about six million watts of power generated on-site by fuel cells, which are a substantially cleaner and more efficient source of energy than coal, in its new data center in South Jordan, Utah. The company also operates PayPal, the online payment service, out of the South Jordan site. Bloom Energy, a private company in Sunnyvale, Calif., will make the fuel cells.