Economic viability assessments of high voltage direct current for wind energy systems

•Improvements in HVDC is critical for wind energy transmission.•An L-cC analysis is conducted through energy scenarios for decision-makers.•A cumulative cash flow analysis is applied for HVDC systems.•LCC and VSC converter types are considered in the calculations.•A real case study of the transmission of wind energy through HVDC in Turkey is proposed. This research shows an economic assessment for decision-makers of high voltage direct current utilization in wind energy systems applied to a case study in Turkey. The increasing energy demand in Turkey can be supplied effectively by this transmission in long distances and leading the use of renewable energy sources. Thereby, wind energy systems are being one of the main developed renewable sources, but the economic feasibility of its feature has been demonstrated only in some cases. The transmission of wind energy is possible both inside a country and between the countries, depending on the deployments about the utilization of high voltage direct current technology, operating with renewable energy systems. Thus, life-cycle cost scenarios are proposed by recommending a 1,000 km length high voltage direct current overhead transmission line in optimum economic conditions between Canakkale and Samsun-Bafra to transport energy from wind farms. The economic feasibility of these systems can be proven by showing the comparison between investment cost and profit from the 25 years life-time of the project. A novel cumulative cash flow analysis is applied for this comparison employing the net present value. A voltage source converter and a current commuted converter are considered in the scenarios. The findings show that voltage source converter can be chosen for both overhead and cable transmission for wind energy systems with the need of government subsidies in the investment. Moreover, the possibility of the investment is discussed through economic terms, i.e., the positive externality, the opportunity cost and the economies of scale. Therefore, this study can be taken as a pre-model for both the other regions of Turkey and for the developing countries.