Pumped hydroelectric energy storage: Analysing global development and assessing potential applications in Turkey based on Vision 2023 hydroelectricity wind and solar energy targets

According to the Vision 2023 agenda, the Turkish government plans to produce 30% of Turkey's electricity demand from renewable energy sources in 2023. This means hydroelectric, wind and solar energy capacities would increase to 36,000 MW, 20,000 MW and 3000 MW, respectively. Increased hydroelectric capacity would indeed benefit stability and flexibility of the existing energy infrastructure. However, increased wind and solar capacity could bring intermittency problems due to nature of these energy sources. Recently, pumped hydroelectric energy storage (PHES) has become a hot topic in Turkey. And, its potential applications via synergistic utilisation with wind and solar energy to solve the aforementioned intermittency problems is being discussed. Yet, detailed information in the literature about PHES in Turkey is scarce. Therefore, this paper was intended to provide this crucial information. Detailed analysis showed even if all obstacles are overcome and all potential PHES capacity is used PHES could only provide a storage capacity worth equivalent to 0.6-0.8% of Turkey's annual electricity demand in 2023. It is estimated that the overnight capital cost required to develop this PHES potential is between 3.6 and 6.5 billion US$. Even so, there would be serious economic risks of PHES plants. Because, PHES systems are currently net consumers of energy. Current study also showed that instead of focusing on PHES, flexibility of Turkish electricity market could be sustained by diversifying energy sources and increasing nuclear energy capacity. It is estimated that an additional 490 MW of nuclear capacity could provide the same potential PHES capacity. By this way, intermittency problems associated with increased share of solar and wind energy can be easily tackled without imperilling the Vision 2023 energy targets.