Future role of ocean thermal energy converters in a 100% renewable energy system on the case of the Maldives
Dominik Keiner, Jannis Langer, Ashish Gulagi, Rasul Satymov, Christian Breyer
Abstract
Energy transition on small islands is limited by the scarce availability of land, restricting large-scale implementation of onshore renewable energy technologies such as solar photovoltaics and wind power. Ocean energy technologies provide novel opportunities for land-constrained islands to achieve 100% renewable energy systems. While wave power is increasingly implemented in energy system modelling research, ocean thermal energy converters are not yet a standard technology in renewable energy technology portfolios. This research aims to study the impacts of ocean thermal energy converters on the energy system of the Maldives through a structured sensitivity analysis for the two scenario clusters covering e-fuel import and domestic production. The ocean thermal energy conversion plants are modelled using spatially and temporally resolved resource data and cost assumptions from a global upscaling scenario, considering the technology's current development stage. Results show that ocean thermal energy converters play a limited role in 'purely' cost-optimised sub-scenarios due to the availability of very low-cost offshore floating photovoltaics, making it difficult for them to compete. Nevertheless, reduced requirement of energy storage technologies due to the stable electricity production of ocean thermal energy converters offers an option to diversify the renewable energy technology portfolio with only a minor increase in cost. • Role of ocean thermal energy converter on the case of Maldives studied. • Structured sensitivity analysis applied to assess the impact on the energy system. • Import and domestic production of e-fuels in 2030 and 2050 modelled. • Ocean thermal energy converter are hardly cost-competitive with solar photovoltaics. • Technology portfolio diversification options are discussed based on results.