A windmill park produces energy at a tension level of 11kV. The park is going to be coupled up with a 11kV net not far from the park. To reduce the loss in transer the tension is tranfomred p at the parka nd down again right before coupling to the 11 kV net. The losses in the transfer reduces by a degree of 8/9 in relation to 11kV. What is the tension level of the transfer line?