Google has signed a 20-year fixed-rate agreement to buy wind-generated power from NextEra Energy Resources.
The agreement is part of Google's plan to become carbon-neutral and to implement socially responsible technology.
From the end of July, NextEra will supply 114 megawatts of wind power from its Iowa facility to supply several datacentres.
Urs Hoelzle, senior vice-president of operations at Google, said in a blog post that the agreement will give NextEra the financial certainty to build more clean energy projects.
"The inability of renewable energy developers to obtain financing has been a significant inhibitor to the expansion of renewable energy," he said.
"We depend upon large quantities of electricity to power Google services and want to make large actions to support renewable energy," he said.
NextEra attributes company growth to increasing demand for emission-free energy, according to US reports.
"With the support of customers like Google Energy we've built our wind fleet from fewer than 500 megawatts a decade ago to more than 7,600 megawatts," said Mike O'Sullivan, senior vice-president of development for NextEra.