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Making Solar "Wallpaper" Cheaper, More Efficient

Organic solar panels show promise for decorative indoor use, while inorganic ones offer potential for cheap, high performance production

1 min read
Making Solar "Wallpaper" Cheaper, More Efficient
Photo: Antti Veijola

I’m sure that there are tons of reasons why solar panels aren’t absolutely everywhere. Expense, aesthetics, and so forth. But really, we should have them wherever light is, shouldn’t we? No reason not to harvest all of that energy, right? VTT Technical Research Centre of Finland has developed a beautiful, flexible, and entirely recyclable type of organic solar panel that can be mass-produced by printing it on film so that it can be as ubiquitous as wallpaper, and look like it, too.

VTT’s organic solar films are just 0.2mm thick, and they come out of a roll-to-roll printing process at 100 meters every minute complete with polymer light collecting layers and electrodes sandwiched inside plastic substrates and films. Graphics can be printed on top as with the leaves in the pictures above and below; one square meter of film works out to be about 200 of these functional leaves, producing 10.4 watts of power (3.2 amps), at least if you’re somewhere in the Mediterranean.


While organic solar panels are certainly flexible and lovely to look at, they tend to be more expensive and less efficient than inorganic solar panels, which are generally made from silicon. By using perovskite instead, it’s possible to make an inorganic solar cell that performs five times better than an organic one, while costing ten times less in materials. The tricky part is figuring out a way to toss perovskite into the roll-to-roll printing process to manufacture inorganic cells efficiently, and that’s what VTT is working on next.

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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