24 May 2019
A new dimension to solar energy
Published online 13 May 2018
Scientists use 3D materials for better solar energy harvesting.
Seawater desalination is dependent on harvesting solar energy by converting sunlight into heat, typically using special 2D structures, called solar evaporators, to collect energy from the sun.
Existing solar energy harvesting systems, however, involve significant energy losses. It’s why scientists at King Abdullah University of Science and Technology (KAUST) have been working at extricating solar heat generation from the boundaries of two-dimensional material while saving energy in the process.
In a new study, published in Joule1, the researchers are showcasing cup-shaped three-dimensional solar evaporators, which they have developed and which can, reportedly, absorb sunlight efficiently as well as recapture reflected sun radiations.
The walls of the new structures can maintain a cooler temperature than that of their surroundings, enabling them to extract even more energy from the surrounding environment, as per the research.
This work does not only report unprecedented heat generation efficiency, reaching almost 100%, but the researchers say it can also inspire a paradigm shift in solar energy research towards three-dimensional materials.
“Going 3D is the future direction for photothermal materials,” says Peng Wang, associate professor of environmental science and engineering at KAUST, and one of the authors of this study.
Wang and colleagues are currently working on upscaling their model, in order to test it in several applications. Production cost is not a big concern, says Wang, “given the nature of the photothermal materials used in our work”.
By optimizing other aspects of the heat generation process, the researchers believe that the once-thought impossible efficiency can be further improved. The team also plans to revisit the conventional system design and find ways to recover and recycle lost energy.
- Shi, Y. et al. A 3D Photothermal Structure toward Improved Energy Efficiency in Solar Steam Generation. Joule http://dx.doi.org/10.1016/j.joule.2018.03.013 (2018).