City University of Hong Kong researchers propose using solar-powered water electrolysis within chemical manufacturing to produce hydrogen without fossil-fuel emissions. The approach, reported in Nature Reviews: Clean Technology, does not reduce energy intensity but enables hydrogen to be converted into higher-value chemicals, potentially making the system self-funding. Experts say the technique could be used at both small, specialized scales for pharmaceuticals and larger scales requiring solar farms, though upscaling poses challenges.
City University of Hong Kong unveils solar-driven electrolysis method that could finance itself
City University of Hong Kong researchers propose using solar-powered water electrolysis within chemical manufacturing to produce hydrogen without fossil-fuel emissions. The approach, reported in Nature Reviews: Clean Technology, does not reduce energy intensity but enables hydrogen to be converted into higher-value chemicals, potentially making the system self-funding. Experts say the technique could be used at both small, specialized scales for pharmaceuticals and larger scales requiring solar farms, though upscaling poses challenges.
09:10, 07.11.2025Technology
Researchers at the City University of Hong Kong have described a new approach for integrating solar-powered water electrolysis into chemical manufacturing, according to a study in Nature Reviews: Clean Technology.
Electrolysis uses electricity to split compounds into their elemental parts, a process that is often costly and environmentally harmful when the power comes from fossil fuels. By powering electrolysis with solar energy, scientists can produce hydrogen without the carbon emissions associated with electricity from burning fossil fuels.
Tech Xplore notes that the chemical industry depends heavily on fossil fuels both to supply electricity for energy-intensive steps such as electrolysis and as feedstocks that become part of chemical products. That dependence leads to large emissions of greenhouse gases throughout chemical synthesis.
Shifting from fuel-based electricity to solar power can cut costs and lower the sector’s carbon footprint because solar energy is renewable and avoids emissions tied to fossil-fuel electricity generation.
The Nature Reviews: Clean Technology article emphasizes that using solar-driven electrolysis does not make chemical production less energy-intensive. Instead, it changes how electrolysis output is valued: hydrogen can be converted directly into higher-value chemical products rather than being sold only as a commodity gas.
"This isn't just about making cleaner hydrogen, but making profitable hydrogen, since when solar electrolysis is turned into a chemical reactor, the whole system can pay for itself," said CityUHK Professor Fatwa F. Abdi in the Tech Xplore report.
Researchers say the solar-electrolysis approach could be deployed at different scales, though scaling up poses additional challenges. For high-value, low-volume products like pharmaceuticals and specialty chemicals, the solar-powered units are likely to be smaller and more specialized.
By contrast, broad-based commodity chemical production would probably require larger solar farms to supply the greater energy demand needed for high-volume manufacturing.
Scientists suggest that funneling solar-generated hydrogen into the synthesis of bioplastics, pharmaceuticals and other specialty chemicals could make the technology economically attractive while reducing lifecycle greenhouse gas emissions from the chemical industry.