Offshore Floating Solar Photovoltaics for Land Constrained and Diverse Supply Conditions in the United States and Canada

Energy transition pathways for large continental areas are largely understood to be achievable using a diverse set of onshore renewable energy technologies. Previous research for the integrated United States and Canada energy-industry system indicated that solar photovoltaics (PV) may dominate the primary energy structure, complemented by onshore wind power. However, societal constraints may require increased supply diversity, and onshore renewable energy may not be sufficient for densely populated regions, especially on the east coast of the United States. The LUT Energy System Transition Model was applied to investigate the role of offshore floating solar PV coupled with offshore wind and wave power when onshore solar PV is limited. The results indicate that, when onshore solar PV is limited to 60% of electricity generation, 434 GW of offshore floating PV may be installed as part of a hybrid power plant sharing the same grid connection as offshore wind power, which reaches 414 GW of installed capacity, contributing 3.1% and 8.1% to the electricity supply, respectively. In total, 7.2 TW of solar PV capacity are installed, complemented by 1.7 TW of onshore wind power. Increased supply diversity still leads to a 42% reduction in levelized cost of electricity, reaching 33.1 euro/MWh in 2050. Compared to cost-optimal conditions, the levelized cost of final energy and non-energy use in 2050 increases by 14% to 47.0 euro/MWh. Nevertheless, such increased costs may be justifiable to meet societal constraints, and a diverse Power-to-X Economy structure for the United States and Canada may still be techno-economically viable.