With the purchase, SunEdison has increased its 2015 installation guidance from a range between 1.6GW and 1.8GW to a range between 2.1GW and 2.3GW.

SunEdison will acquire more than 1.6GW of pipeline and backlog projects, which have been added to TerraForm Power’s call right project list.

SunEdison president and chief executive officer Ahmad Chatila said: "The acquisition of First Wind transforms both SunEdison and TerraForm Power into diversified renewable energy companies and will make SunEdison the leading renewable power plant developer in the world."

The transaction also comprises an additional 6.4GW of project development opportunities.

TerraForm Power president and chief executive officer Carlos Domenech said: "We are adding significant CAFD through a transaction with a greater than 9% levered cash-on-cash yield, increasing our dividend by 44% and expanding the potential drivers of our long-term growth."

First Wind chief executive officer Paul Gaynor said: "This new strategic organization will allow us to join with SunEdison to develop and invest in new, long-term-contracted, well-sited and well-run renewable energy projects that deliver clean energy to homes and businesses across the country and internationally."

With the transaction, TerraForm will add 521MW of First Wind assets to its portfolio with 1.6GW of projects anticipated to be dropped down in 2016 and 2017.

Expected to be completed in the first quarter of 2015, the transaction is subject to regulatory approvals.

Image: First Wind is constructing renewable energy projects in the US. Photo: Courtesy of First Wind.