Blue energy advances unlock sustainable power from water
image: Representative TENG Architectures for Efficient Blue-Energy Harvesting. This figure illustrates several triboelectric nanogenerator (TENG) designs engineered to capture low-frequency ocean-wave energy, including rolling-ball structures, 3D self-assembling networks, duck-shaped oscillators, fur-brush systems, and active-resonance mechanisms. These innovations enhance durability, sensitivity, and energy-conversion efficiency, enabling scalable and high-performance blue-energy harvesting in marine environments.
Credit: Ocean, Tsinghua University Press
Rising global energy demand and increasing carbon emissions have intensified the urgency for clean, renewable alternatives to fossil fuels. Water-derived energy—including hydropower, tides, waves, ocean currents, salinity gradients, and offshore hybrid systems—represents one of the planet’s largest and least exploited renewable resources. Hydropower already provides over 16% of global electricity, while ocean energy offers theoretical potential measured in thousands of terawatt-hours each year. Despite this promise, challenges remain, such as ecological impacts, the limited maturity of wave-energy technologies, and the high maintenance cost of offshore systems. Given these challenges, in deepth research is needed to explore resource potential, optimize technologies, and develop sustainable pathways for blue-energy deployment.
A research team from the Guangzhou Institute of Blue Energy and the Beijing Institute of Nanoenergy and Nanosystems published (DOI: 10.26599/OCEAN.2025.9470004) a comprehensive review in Ocean in March 2025, examining the scientific progress shaping the development of blue energy, first introduced by Wang in 2014. The review analyzes hydropower, ocean-energy technologies, and emerging offshore hybrid systems that integrate wind, solar, and wave power. It also spotlights rapid breakthroughs in TENGs, which offer high efficiency in capturing low-frequency wave energy under harsh marine conditions, positioning them as a next-generation solution for ocean-energy harvesting.
The review first summarizes hydropower’s global landscape, noting more than 1300 GW of installed capacity and its contribution of over 16% of worldwide electricity generation. Although hydropower is technologically mature, its growth rate has slowed in developed countries. In contrast, ocean-energy technologies—especially tidal and wave power—are expanding. Mature tidal stations such as France’s Rance facility demonstrate commercial viability, while modern wave-energy converters (WECs), including point absorbers and attenuator-type devices, continue to advance in efficiency and deployment scale.
A major focus of the review is TENGs, which exhibit distinct advantages over electromagnetic generators in low-frequency, small-amplitude marine environments. Several TENG architectures are highlighted, such as rolling-ball systems, 3D self-assembling networks, duck-shaped oscillators, and soft-contact brush designs. These devices achieve high performance and offer extended durability, omnidirectional energy harvesting, and the potential for large-area, self-powered networks.
The review further explores offshore hybrid systems that integrate wind turbines, floating solar arrays, and TENG-based wave harvesters into unified platforms. These multisource systems aim to maximize energy density, reduce sea-space occupation, and lower long-term generation costs. Such innovations position hybrid offshore networks as a promising frontier for future renewable-energy infrastructure.
The authors emphasize that blue energy holds enormous promise for achieving global carbon-neutrality goals. They note that rapid technological progress—particularly in wave-energy harvesting and TENG development—will significantly reshape the renewable-energy landscape. The review reiterates the urgent need to replace fossil fuels with ocean-based energy systems to substantially reduce greenhouse gas emissions. By combining wind, solar, and wave power into integrated offshore platforms, called hybrid energy, the researchers argue, nations can accelerate large-scale deployment and overcome resource limitations, paving the way for a more resilient and sustainable global energy structure.
Blue-energy technologies have broad potential applications, from supplying clean electricity to coastal communities and offshore platforms to powering autonomous marine sensors for environmental monitoring. Hydropower will continue to deliver stable baseload energy, while ocean-wave and hybrid offshore systems are poised for rapid expansion as device durability and efficiency improve. TENG-based wave harvesters may also support distributed, self-powered sensing networks essential for climate observation and ocean-ecology management. As countries accelerate decarbonization, integrated offshore systems combining wind, solar, and wave energy will reduce land occupation, lower power-generation costs, and make substantial contributions to global zero-carbon strategies.
About Ocean
Ocean is an international, peer-reviewed, open-access journal that provides a multidisciplinary platform for cutting-edge research and practical applications in the fields of ocean science, marine technology, and marine engineering. The journal publishes articles, reviews, and perspectives aimed at advancing theoretical, numerical, site-based, and experimental developments to promote global sustainability.