With the number of offshore wind farms rapidly increasing, in a wide variety of site conditions and using different turbine sizes, the need for alternative support structures other than the conventional monopile structure is apparent and several projects have been realised using other support structure types. In this report the results of Upwind Work Package 4, task 4.2 are reported. The aim of task 4.2 is to develop support structure concepts for large offshore wind turbines and deep water, including bottom mounted very soft and floating structures.