Introduction  With the “Guidance for bidding of the wind power farm development ” having been published, the demand of reducing the development cost is more and more urgent. Therefore, it is crucial to reduce the cost through technological innovantion. The cost of tower and foundation significantly affects the Levelized Cost of Energy(LCoE) of offshore wind and directly determines the competitiveness of offshore wind developer.

  Method  This paper aims at applying an integrated Design Offshore (iDO) approach based on a digital cloud platform for an offshore wind turbine tower and foundation design in the ULS and the FLS conditions, respectively. To show the effectiveness of the iDO approach in reducing the cost of the tower and foundation, a sequentially iterated approach (SIA) was also used for a comparison using two of our offshore wind power projects.

  Result  The results we obtained demonstrate that the design loads are all much smaller by using the iDO approach than the SIA approach in both ULS and FLS conditions. Our calculation results suggest that the iDO approach can significantly optimize the design process and reduce the weight and cost of the supporting structures, as well as the LCoE of offshore wind farm.

  Conclusion  In the practical engineering projects of offshore wind farms, the iDO approach can significantly reduce the integrated tower & foundation cost and enhance project competitiveness. This work also provides some guidance for further study on the supporting structures design optimization by applying the iDO approach.