Bloomberg Businessweek

Google (GOOG) is stepping up wind-power purchases to reduce emissions, even as it devotes most of its renewable energy investments to sun-related projects, a trade-off aimed at reining in costs as the company seeks higher returns.

Google drew 30 percent of the energy it consumed last year from renewable sources, virtually all of it from wind, up from 19 percent a year earlier. Yet of the $917 million that the company has invested in renewable-energy projects, about two-thirds?or $622 million ?is channeled toward solar.