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Solar Paint is Easy to Make, Needs Efficiency Improvements

Paint-on solar so far only reaches 1 percent conversion efficiency.

1 min read
Solar Paint is Easy to Make, Needs Efficiency Improvements

Researchers at Notre Dame have developed a simple and cheap alternative to traditional solar cells: solar paint. The one-coat paint, made with semiconducting nanoparticles, achieved a one percent conversion rate when tested using artificial sunlight. This is far behind other solar technologies -- which fall in the 10 to 15 percent range, generally -- but the ease of manufacturing and use are clear advantages of the paint idea. They published a paper on the subject in ACS Nano.

The researchers, led by Prashant Kamat, created an alcohol-based paste consisting of cadmium sulfide, cadmium selenide, and titanium oxide semiconducting nanoparticles. They then annealed the paste on a conducting glass surface, and sandwiched an electrolyte solution between the paste and a graphene composite electrode to achieve their one percent efficiency. A quick video explaining the process is below.

Clearly, the Notre Dame group will have to make some improvement in efficiency for this to be a viable alternative to traditional solar cells. "But this paint can be made cheaply and in large quantities," Kamat says in a press release. "If we can improve the efficiency somewhat, we may be able to make a real difference in meeting energy needs in the future." This work joins earlier efforts toward sprayable, printable, and paintable solar tech, so it's good to see progress in the field. There is reason for optimism here, so I suppose we can forgive the Notre Dame team their product's unfortunate pun of a name: Sun-Believable.

(Image and video via Notre Dame)


The Conversation (0)
This photograph shows a car with the words “We Drive Solar” on the door, connected to a charging station. A windmill can be seen in the background.

The Dutch city of Utrecht is embracing vehicle-to-grid technology, an example of which is shown here—an EV connected to a bidirectional charger. The historic Rijn en Zon windmill provides a fitting background for this scene.

We Drive Solar

Hundreds of charging stations for electric vehicles dot Utrecht’s urban landscape in the Netherlands like little electric mushrooms. Unlike those you may have grown accustomed to seeing, many of these stations don’t just charge electric cars—they can also send power from vehicle batteries to the local utility grid for use by homes and businesses.

Debates over the feasibility and value of such vehicle-to-grid technology go back decades. Those arguments are not yet settled. But big automakers like Volkswagen, Nissan, and Hyundai have moved to produce the kinds of cars that can use such bidirectional chargers—alongside similar vehicle-to-home technology, whereby your car can power your house, say, during a blackout, as promoted by Ford with its new F-150 Lightning. Given the rapid uptake of electric vehicles, many people are thinking hard about how to make the best use of all that rolling battery power.

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