Winning a big contract to work on three offshore wind farms in the United States is boosting the expansion plans of Christchurch's Truescape.

The US now represents a third of Truescape's revenue, just 15 months after the company first began focusing on the country.

Truescape makes three-dimensional (3D) video simulations to show people what proposed projects like wind farms would look like on the landscape before they were built.

It has already worked on a number of New Zealand's wind energy projects, including Meridian Energy's White Hill in Southland and Te Apiti near Palmerston North.

The US contract will see it working on wind projects being built by Bluewater Wind off the coasts of New Jersey and Maryland.

Each wind farm was around 200 megawatts in size, much bigger than New Zealand's wind farms with White Hill producing 58MW and Te Apiti 90MW.

Truescape chief executive Robert Mann said the company won the contract from a European competitor which had worked with Bluewater previously.

"We were chuffed to win and to beat someone else as well is great."

Bluewater Wind is owned by Babcock and Brown, the world's third largest wind energy provider with interests in 68 wind farms on three continents.

Mann said having such a high profile client would help the company pick up more work in the US, where it already had six customers.

"The US provides us with so much opportunity."

In the next four years Mann expected to see its revenue from the US grow to become four times the size of the present business.

It planned to open four offices in the US with 10 to 15 staff in each.

Mann hoped to have the first office opened within a year, but the company needed some additional investment to do that.

It was looking for a few million dollars to help it grow. Founder Sam Chaffey, who was still involved in research and development, was the majority shareholder. Despite the US expansion Christchurch would remain the centre for research and development and the US offices would be mainly client focused.