E.ON said it bought Irish wind farm operator Airtricity's North American operations for $1.4 billion.
E.ON said in a statement that the purchase price is subject to closing adjustments and includes $553 million net debt and shareholder loans.
The German utility said it expects the transaction to close by the end of 2007.
It said Airtricity's installed capacity is 210 megawatts, with an additional 880 MW operational by the end of 2008.
It said more than 1,000 MW of additional projects are in an advanced development stage. These projects will require an investment volume of around 3.5 bln usd until 2011.
Other projects across the US and Canada totaling more than 5,000 MW capacity are in an early development stage, E.ON said.