Abstract
Renewable energy sources, such as solar and wind sources, play a pivotal role in the decarbonisation of energy systems and yet pose a significant challenge in management due to their variable and intermittent nature. This work investigated the optimisation of a renewable energy system using hydrogen via water electrolysis as an energy carrier to mitigate the variability of renewable sources. The techno-economic assessments were performed using the meteorological data from two case study locations, i.e. Kramer Junction (US) and Norderney (Germany). The optimal levelised energy cost is found to be 227 $/MWh and 167 $/MWh for the two locations, respectively. The cost breakdown reveals additional insights into the combined scheduling and capacity planning and illustrates the drivers for the increase in cost when more variable renewable sources are incorporated. The impact of electrolyser operationality was explored, showing a two-regime behaviour of the economic potential governed by a critical ramp-up limit, below which the economic potential of the energy system becomes highly sensitive to the operationality. The reliability of the renewable energy system is monetised using the loss-of-power analysis, which reports the economics as a function of reliability. Although it is more expensive to level the power output of a more variable source, its economics can be effectively improved by compromising the reliability of the energy system.
•Comparison between hydrogen- and battery-based energy storage system.•Impact of variable renewable sources on energy system economics.•Load-dependent electrolysers efficiency and its influence on economics.•Monetisation of renewable power system reliability.