What are the unique challenges of offshore wind development?

Offshore wind challenges include: foundation design (monopile, jacket, floating for deep water - significant cost), harsh marine environment (corrosion, salt spray, high humidity), installation logistics (specialized vessels, weather windows), grid connection (HVAC or HVDC subsea cables, offshore substations), operations and maintenance access (vessel transfer, helicopters, accommodation), higher costs (2-3x onshore historically), permitting complexity (multiple jurisdictions, environmental review), and supply chain constraints. Benefits include stronger, steadier winds, larger turbines (up to 15+ MW), and proximity to coastal load centers.