The Offshore Proof Turning Windpower Promise into Performance survey, was based on interviews with developers, wind-farm operators, manufacturers, and policymakers across countries including Germany, Denmark, the UK, China and Japan.
Asked whether technological breakthroughs would support or undermine offshore wind power in the energy mix over the next 20 years, 63% of respondents said there was a medium chance it would undermine it and that offshore wind could be eclipsed by other technologies.
Of those surveyed, government respondents were the most optimistic about the effect of technological change on the economics of offshore wind.
PWC commented: "The coming few years will be make or break time in deciding whether offshore wind will be able to get on track to prove its place as a source of large-scale generation.
"Ultimately it needs to show it can reach efficiencies and cost levels near enough to onshore installations to make it competitive in the energy mix."