Abstract: A method of retrofitting a wind turbine having a tower and a first energy generating unit with a second energy generation unit is disclosed. The wind turbine has been operated for a first period of time at a first tower life rate and has a first tower life expectancy design value. The method includes determining the tower life of the wind turbine tower used during the first period of time; determining the remaining tower life of the wind turbine tower; replacing the first energy generating unit with the second energy generating unit; and operating the retrofitted wind turbine at a second tower life rate less than the first tower life rate so as to extend the life expectancy value of the tower beyond the first tower life expectancy design value.

Abstract: A method of retrofitting a wind turbine having a tower and a first energy generating unit with a second energy generation unit is disclosed. The wind turbine has been operated for a first period of time at a first tower life rate and has a first tower life expectancy design value. The method includes determining the tower life of the wind turbine tower used during the first period of time; determining the remaining tower life of the wind turbine tower; replacing the first energy generating unit with the second energy generating unit; and operating the retrofitted wind turbine at a second tower life rate less than the first tower life rate so as to extend the life expectancy value of the tower beyond the first tower life expectancy design value.

Abstract: A method of retrofitting a wind turbine having a tower and a first energy generating unit with a second energy generation unit is disclosed. The wind turbine has been operated for a first period of time at a first tower life rate and has a first tower life expectancy design value. The method includes determining the tower life of the wind turbine tower used during the first period of time; determining the remaining tower life of the wind turbine tower; replacing the first energy generating unit with the second energy generating unit; and operating the retrofitted wind turbine at a second tower life rate less than the first tower life rate so as to extend the life expectancy value of the tower beyond the first tower life expectancy design value.

Abstract: A method of retrofitting a wind turbine having a tower and a first energy generating unit with a second energy generation unit is disclosed. The wind turbine has been operated for a first period of time at a first tower life rate and has a first tower life expectancy design value. The method includes determining the tower life of the wind turbine tower used during the first period of time; determining the remaining tower life of the wind turbine tower; replacing the first energy generating unit with the second energy generating unit; and operating the retrofitted wind turbine at a second tower life rate less than the first tower life rate so as to extend the life expectancy value of the tower beyond the first tower life expectancy design value.

Abstract: The invention relates to a wind turbine tower comprising at least two adjacent metal tower plates. The wind turbine tower is characterized in that, the tower plates are connected by one or more fish joints. The invention further relates to a wind turbine and a method for assembling a wind turbine tower.