A preliminary techno-economic comparison between a grid-connected and non-grid connected offshore floating wind farm

Non-grid connected (NGC) floating offshore wind (OW) turbines can signify a solution for harvesting wind energy far offshore, addressing some key issues including the deep waters and lack of grid connection, while also exploiting the higher capacity factors. Towards this direction, on-board energy storage in the form of hydrogen production is one of the most promising solutions, often cited in literature. This study aims to perform a preliminary techno-economic analysis to assess the trade-offs, in terms of cost, between a far offshore grid-connected (GC) floating wind farm and a NGC wind farm integrated with an electrolyser for the production of hydrogen. To this end, a lifecycle techno-economic model coupled with an O&M model developed for offshore wind installations are employed. The model is applied to a hypothetical wind farm located 200km from the shore. For the GC system, O&M costs along with the costs of acquisition of the electric system (offshore cable and offshore substation) appeared to be the main contributors to the Levelised Cost of Electricity (LCOE). As far as the NGC system is concerned, it was concluded that a higher annual capacity factor (>60%) could potentially achieve viability of the investment.