US electricity giant Duke Energy has become one of the world's largest wind power companies following its purchase of Catamount Energy for $320m.

North Carolina-based Duke, one of the largest electricity providers in the US, said the acquisition would enable it to provide 500 megawatts of wind energy – enough to power 500,000 homes – by the end of the year.

The deal also gives it 5,000 megawatts of wind energy projects under development in the UK and across 12 US states.

President of the company's Duke Energy Generation Services (DEGS) business unit, Wouter van Kempen told reporters: "You can build large utility scale wind farms and power plants relatively fast compared to anything else, and build them cheaper than any renewable energy at this stage. That makes wind very attractive to us."

The purchase is the latest in a series of moves underlining the energy giant's interest in the global renewable energy sector. It has been snapping up green assets for more than 12 months, including most recently a decision to buy rights to the total electricity output of the country's largest solar energy farm, which is to be built just north of its Charlotte headquarters.

Last month, the company also outlined plans for a $100m project designed to install solar panels on the properties of customers in North Carolina.

The move is also a further example of the consolidation impacting the market, which has seen a number of large scale traditional energy generators acquire independent wind operators in recent months. Most notably, UK utility Scottish and Southern Energy (SSE) shelled out €1bn earlier this year to acquire Irish firm Airtricity.

The world market for wind turbines grew by approximately 30 per cent in 2007 to 20,000 megawatts. It is worth around $37bn.