The purpose of defining the NOWITECH reference wind farm is to create a base case model to use in further research and for benchmarking. The reference wind farm is a 1200 MW offshore wind farm similar to a UK round 3 wind farm. It employs 120 10 MW DTU reference turbines, and is split into three sections that is connected to a VSC station that connects the wind farm to shore. Each of the three sections is connected via a 400 MW transformer substation. The configuration is similar to that of a state of the art wind farm; the exception is the collector grid voltage that is set to 66 kV. The collector grid lay out and cable types are presented together with substation configuration, wind turbine electrical data, and transmission system data. The MATLAB Simulink model created to simulate the reference wind farm is also presented with suggestions for further works.