A new invention has demonstrated an inexpensive transparent coating that reduces the accumulation of snow and ice on solar panels, allowing them to generate up to 85% more energy in the first tests.
In a breakthrough that could dramatically improve the productivity of solar panels in cold climates, developed by a team led by the University of Michigan.
The coating is made primarily of PVC or PDMS plastic and silicon or vegetable oils. It can be sprayed or brushed in cold weather, and in its current iteration it can continue to shed snow and ice for up to a year.
“Renewable energy is really taking off right now, but snow is a big problem in northern climates.”said Anish Tuteja, a professor of materials science and engineering at the Michigan University, who led the study in collaboration with Sandia National Laboratories and the University of Alaska.
“Solar panels could lose 80 to 90% of their generating capacity in the winter. So finding a way for them to continue to generate power throughout the year was an exciting challenge. “added.
Although Tuteja’s lab has developed a number of effective ice-shedding coatings in the past, he commented that creating a coating that can passively shed both snow and ice represents a special challenge.
“Ice is relatively dense and heavy, and our previous coatings used their own weight against it”Tuteja said. “But snow can be 10 times less dense than ice, so we weren’t sure if the tricks we used on ice would translate into snow.”.
To find the right coating, Tuteja and her team turned to two key properties that have driven ice release coatings in the past: low interfacial toughness and low bond strength. Low surface adhesion is basically slippage. Gliding alone works well in small areas, but the larger the surface, the more force it takes to slide snow and ice off of it. For larger areas you need a way to break the adhesion completely. This is what low interfacial toughness does: it creates cracks between the ice and the panel. These spread throughout the panel, regardless of its size, breaking free ice and snow.
The team worked to achieve precisely the right balance of low surface adhesion and low interfacial toughness that would repel both ice and snow from small and large surfaces alike. They started with very stiff PVC plastic, for low interfacial toughness, and were mixed in a small amount of vegetable oil which gave the PVC low enough surface adhesion to provide the best of both worlds. They also came up with a second material that works equally well using PDMS plastic and silicon-based oil.
The UM researchers collaborated with the University of Alaska to test the material in a solar field in Fairbanks, Alaska, applying the coatings to a subset of panels that were monitored by automated cameras over a period of about two weeks. The tests showed that the coated panels had an average snow and ice coverage of approximately 28% for an entire winter season, compared to approximately 59% for the uncoated panels.
The coating was developed as part of a project led by Sandia National Laboratories, a US Department of Energy research and development laboratory, with funding provided by DOE’s Office of Solar Energy Technologies.
“Snow phobic coatings, if we can demonstrate their long-term effectiveness, will make solar power more reliable and more affordable in snowy regions, helping to accelerate our nation’s transition to a more energy-dominated energy economy. solar energy, “added Tuteja.