Offshore wind to dominate, but hybrid systems hold key to net-zero goals

The review stresses that offshore renewable technologies face formidable barriers. The costs of development and operation in harsh marine environments remain high. Harsh conditions also shorten equipment lifespan and demand significant investment in maintenance and resilience.

Offshore renewable energy is set to become a central player in the global effort to reach net-zero emissions by mid-century, but progress will depend on cost reduction, regulatory clarity, and technological innovation. A new review examines the state of offshore wind, wave, tidal, floating solar, and hybrid systems, outlining both the opportunities and challenges.

Their article, “A Review of Offshore Renewable Energy for Advancing the Clean Energy Transition,” published in Energies, provides a comprehensive overview of how offshore renewables can accelerate decarbonization while highlighting the hurdles that still stand in the way.

How central is offshore energy to the clean transition?

Offshore renewable energy is not a marginal technology but a cornerstone of the global energy transition. Offshore wind dominates the sector today, with 83.2 gigawatts installed worldwide, and projections suggest growth to as much as 1600 gigawatts by 2050. Fixed-bottom wind farms in shallow waters remain the most mature technology, but floating offshore wind represents the next frontier, opening access to deeper seas with stronger, steadier winds.

Other technologies, including wave and tidal energy, are far less developed but hold significant promise. Global potential is estimated at 180 gigawatts for wave and 120 gigawatts for tidal by mid-century. Although these figures pale in comparison to offshore wind, they could serve as valuable complements due to their predictability and ability to balance grid loads.

Floating solar photovoltaics, especially in offshore environments, are also gaining attention. Large-scale pilot projects in China demonstrate the potential to harness untapped ocean space for solar generation, with additional efficiency gains from natural cooling by water. When integrated with aquaculture or co-located with offshore wind farms, floating solar offers a way to maximize ocean resources.

What challenges stand in the way?

The review stresses that offshore renewable technologies face formidable barriers. The costs of development and operation in harsh marine environments remain high. Harsh conditions also shorten equipment lifespan and demand significant investment in maintenance and resilience.

Environmental concerns feature prominently. Offshore wind farms, for example, have been linked to bird collisions, habitat disturbance, and seafloor impacts during construction. For wave and tidal projects, the effects on marine ecosystems are not yet fully understood, raising caution around widespread deployment until long-term impacts are clearer.

Regulation and grid integration are equally problematic. Permitting processes are complex and slow, often delaying projects by years. Wake effects, where turbines interfere with one another’s efficiency, reduce overall energy yields and complicate offshore wind farm design. Grid infrastructure, especially in regions with weak transmission networks, lags behind the rapid growth of renewable installations.

The study also notes risks associated with energy markets. Negative pricing events, where excess renewable supply depresses prices, threaten to undermine profitability if not managed with robust forecasting and storage solutions. Artificial intelligence and predictive analytics are identified as key tools to help balance production and consumption in future offshore grids.

What role will hybrid and integrated systems play?

Hybrid offshore systems combining multiple renewable technologies are expected to play a growing role in the future. The review highlights experimental platforms that merge offshore wind, wave, and hydrogen production. Others integrate floating solar with wind or aquaculture, creating multifunctional marine spaces that maximize output and efficiency.

Hybrid systems can also address intermittency by leveraging the complementary strengths of different renewables. For example, tidal flows are predictable and consistent, while wind and solar are variable. Combined with energy storage solutions such as batteries or hydrogen, these integrated systems offer pathways toward stable, resilient power supplies.

Clean energy transition, as the authors stress, will not be driven by one technology alone. Offshore wind will remain the backbone of growth, but complementary technologies, wave, tidal, and floating solar, will provide niche contributions that improve grid stability and expand the resource base. Investments in innovation, cost reduction, and cross-sectoral integration will determine whether offshore renewable energy meets its full potential by 2050.