significant delays and cost overruns Additional costs caused by the o ff shore

Significant delays and cost overruns additional costs

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significant delays and cost overruns. Additional costs caused by the o ff shore converter stations are reported for both ABB and Siemens [62]. However, no final costs including the overruns have been published for these delayed projects. Given the limited availability of information, the cost figures presented here rely on publicly accessible awarded contractual volumes in press releases. Based on reported additional cost for Siemens and ABB [62], [51], the cost overruns are captured and included as far as possible. BorWin1 was built by ABB as the first HVDC connection for o ff shore wind, and it is the only one based on two-level-converter technology. The project’s commissioning phase took about seven months longer than expected [51]. Even after this extended commissioning phase, problems continued for several years resulting in significant down-times [63], [64], [65]. DolWin1 and DolWin2 were entirely built by ABB. These each included the two converter stations, the cable system, and the o ff shore platform. BorWin2 , HelWin1 , SylWin1 and HelWin2 were built by a consortium of Siemens AG and Prysmian Group. Siemens was responsible for the converter stations and the o ff shore platforms while Prysmian was in charge of the cable system. DolWin3 was awarded to a consortium of Alstom and Prysmian Group. The project’s commissioning is expected in mid-2017. BorWin3 di ff ers from its preceding projects to the extent that it has been awarded in two separate tenders, one to Siemens (together with Petrofac) and another to Prysmian Group. Initial power transmission on the link is to commence in early 2019. 6. Evaluation Methodology Based on the collected data on contracted cost for the reference projects, the reference investment cost for the individual projects is calculated according to Equation (7). C ref , i = 11 10 C con ref , i i I B2B C ref , i = 5 4 C con ref , i i I ITC (7) C ref , i = 5 4 C con ref , i i I OWC These estimated markups are accounting for the di ff erence between reference contractual cost C con ref , i and total project reference investment cost C ref , i . These di ff erences are caused by many di ff erent factors, including, but not limited to, internal e ff orts, risk budget, engineering and concession costs, land purchase, construction etc. The markup values are based on [9], [51], [66] and unquotable personal communication with relevant industry stakeholders. For each individual reference project, the cost estimation is calculated with each available cost 8
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parameter set. These cost estimations are then compared with the reference investment cost and the relative deviation is expressed on a logarithmic scale, expressed by Equation (8). D k i = log 2 C k est , i C ref , i (8) Relative deviations guarantee an adequate assessment of both small and big projects. Using absolute cost figures would undervalue the correct estimation of smaller projects.
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  • Fall '10
  • BOB
  • Electric power transmission, Cost overrun, VSC, VSC HVDC

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