Offshore wind-to-hydrogen: the impact of intermittency on hydrogen production and transport

Abstract

Offshore wind is a promising renewable energy source for green hydrogen production, providing a versatile solution for energy storage and power-to gas concepts. This research investigates how the intermittent nature of offshore wind impacts the components of an offshore wind-to-hydrogen system. Proton exchange membrane electrolysers are frequently identified as being best suited to integration with intermittent renewables. However, stop-start cycling of current from a variable power supply can damage electrodes and reduce electrolyser lifetime. Therefore, a small current is required during no wind periods to prevent electrolyser degradation. An intermittent offshore wind resource can also impact pipeline transport of hydrogen. Variable hydrogen production leads to fluctuating hydrogen flow in pipelines. The resulting pressure variations, combined with the potential occurrence of hydrogen embrittlement in steel pipelines can increase the potential and severity of fatigue crack growth, thereby impacting pipeline integrity. Careful selection of pipeline materials and buffer storage to smoothen gas flows, can mitigate these potential impacts. This research proposes a configuration for hydrogen production on an offshore platform from a floating wind farm. It uses battery and hydrogen storage offshore to provide buffers, mitigating the potential impacts of intermittency on each component of the offshore wind to hydrogen system.