Review of investment model cost parameters for VSC HVDC transmission infrastructure

Comprehensive cost reference data has been collected from realised and contracted VSC HVDC projects (back-to-back, interconnector, and offshore wind connection). The cost parameter sets have been evaluated against the reference project cost data. This evaluation has again shown large variations between the parameter sets. On average, the cost for back-to-back systems are slightly underestimated, interconnectors are overestimated, and offshore wind connections are heavily underestimated. To clearly state the validity and limitations of this comparison and evaluation, the applied methodology with its compromises and drawbacks is discussed in detail. Considering the interest in and momentum of offshore grid development, as well as the number of offshore grid investment and evaluation studies being conducted, both the availability of reliable cost reference data and the validity of investment model cost parameters need continuing attention.