In November last year, GE announced it would be installing the first 4.1 in Sweden's Gotherburg harbour. It is the first offshore turbine GE has installed since 2003.
The trial began on 29 February and consisted of 200 hours testing with the turbine reaching a capacity factor of 35.3%.
GE offshore product manager Vincent Schillings said: "Now we will begin validating the design and obtain initial results before the summer wind season.
"Our initial focus will be on the power curve and loads validation as evidence that our simulations meet measurements of the two most important characteristics that matter to our customers."
The 4.1-113 is a scaled-up version of ScanWind's 3.5MW turbine, which has operated for the last five years along the Norwegian coast. ScanWind was acquired by GE nearly three years ago.
However, there is still no news on where the turbine will be manufactured. In 2010 GE announced EUR110 million 2010 plans to manufacture the turbine in the UK, which it believed could result in up to 2000 jobs by 2020. However, last year it appeared to have pulled back on the move.
Speaking to Windpower Monthly, GE general manager renewable energy Europe Stephan Ritter said there was still "no specific manufacturing plans. The next thing is to validate the turbine."