From left: Dr. Malkeshkumar, Professor Jun-Dong Kim, Dr. Fabio Matteocci, Professor Aldo Di Carlo (Director of CNR-ISM)

Incheon National University (President Lee In-Jae) announced that Professor Jun-Dong Kim’s research team from the Department of Electrical Engineering, College of Engineering (Dean: Jun-Dong Kim), has recently developed an active underwater solar energy generation system. This research is drawing attention as it marks the world’s first development of a solar power generation method in which power output is enhanced through interaction with water.

Solar power generation, a leading renewable energy technology that converts light into electricity, is gaining prominence as a core solution for eco-friendly energy supply. However, conventional ground-based installation methods can cause environmental side effects such as deforestation. Additionally, when solar facilities are located far from areas of high energy demand, the need to construct large-scale power transmission infrastructure imposes significant limitations on installation and utilization.

Underwater Solar Cell Demonstration

The underwater solar power generation technology recently developed has been designed for application in urban lakes, coastal areas, and oceans, and has demonstrated significantly improved power generation efficiency compared to conventional land-based systems. This not only enhances spatial utilization but also minimizes environmental damage, proving the potential of this next-generation solar energy model capable of high-efficiency power production.

The core technology of this development lies in using water as a photonic enhancement medium, which significantly increases the amount of sunlight reaching the solar cells. Specifically, it utilizes the refractive index of water (1.33) to effectively enhance the efficiency of underwater solar power generation.

This underwater solar power system has been developed in two forms. The first is an environmentally friendly system based on transparent solar cells that allow light to pass through, enabling power generation while preserving the underwater ecosystem. The second applies commercial silicon solar cells in underwater environments, which is suitable for large-scale installations on open water surfaces such as oceans and lakes.

Dr. Malkeshkumar Patel, adjunct professor at Incheon National University and lead developer of the technology, explained, “The underwater solar power generation technology developed in this study can be applied not only to aquatic environments but also to conventional terrestrial solar systems. It offers a technological advantage by effectively suppressing thermal degradation (power loss) caused by temperature rise during operation.” He added, “By simultaneously improving thermal management and light utilization underwater, this technology can increase solar cell efficiency by more than 2–3%, contributing to the stable maintenance and enhancement of power output in solar power systems.”

One of the most notable strengths of this technology is its capability to generate power both on land and underwater using the same solar cell module configuration—a so-called “amphibious solar power system.” This breakthrough overcomes the efficiency limits of traditional land-based systems and offers flexible deployment in various environments such as urban waterfronts and marine spaces. It is being recognized as the world’s first amphibious solar cell technology.

Professor Jun-Dong Kim, principal investigator of the project, stated, “This underwater solar power generation technology was developed as a proprietary domestic innovation and is expected to be a core technology for leading the future solar market, which is projected to reach approximately 77 GW and 2 trillion KRW by 2033.” He further emphasized the strategic value and industrial impact of the technology, saying, “This technology will play a key role in transitioning to carbon-neutral energy based on solar power.”

Related Papers

The transparent underwater solar cell technology developed in this research was published under the title “Transparent underwater power windows: Enhanced light management and harvesting with water-embedded wide-bandgap heterojunction photovoltaics for sustainable energy” in Nano Energy, and the silicon underwater solar cell technology was published under the title “Water-driven photovoltaics: Enhancing performance through water media in the active layer” in Materials Today Sustainability.

In particular, the paper on the silicon underwater solar cell involved participation from the Italian government research institute CNR-ISM (Director: Aldo Di Calro). Incheon National University and the CNR-ISM research institute have established a cooperative system focusing on the development of transparent solar cells and underwater solar power generation technologies, and they plan to use this collaboration as a foothold for expanding the technological impact and entering the global market through the discovery of future international joint research projects.

A representative from Incheon National University stated that this technology has been applied for a domestic patent (“Underwater solar power system using silicon-based underwater solar power module,” Application No. 10-2025-0084673) and registered (“Oxide semiconductor transparent solar cell, method of manufacturing the same, and underwater solar power system using the oxide semiconductor transparent solar cell,” Registration No. 10-2810865), and that the university is currently in the process of preparing for international patent applications.

Photo of the Registered Patent

Reference Material:

[Refractive Index: Light travels at a constant speed in a vacuum (or air), but its speed changes when it propagates through other substances. The refractive index, which represents the ratio of the reduced speed of light in a medium compared to its speed in a vacuum, significantly affects the linearity and reflection of light. In other words, if the path of light involves gradual changes in the refractive index, light transmission becomes much more efficient. In contrast, large changes in refractive index within a medium hinder light propagation and increase reflection, thereby reducing the amount of light incident on the solar cell and lowering its power generation efficiency. For example, designing a sequential light path (air refractive index: 1, water refractive index: 1.33, solar cell surface refractive index: ~2) significantly reduces solar light reflection and focuses more light onto the solar cell, thereby greatly improving solar power performance compared to the general case (air refractive index: 1, solar cell surface refractive index: ~2).]