Sustainable cities

Australian scientist Scott Watkins explains how, in the cities of the future, a multitude of surfaces could be generating power—thanks to flexible solar cells.  

Video source: Scienceworks.

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I’m Scott Watkins, and I’m working to make solar panels using new processes where we can print them.This enables us to make energy generation sources that can be low cost, lightweight, and used in ways that we haven’t even imagined yet.

The sun provides a huge amount of energy for us. In fact, more energy hits the surface of the earth in one hour than we consume in a whole year. By developing new sorts of solar panels, we can generate electricity by having them on surfaces in all aspects of our lives.

Printable solar cells mean using things like this, a printer, to make a solar panel that generates electricity. It’s exciting because this is a way of making these solar panels that's really cheap, really easy, and can be done really quickly. And the product that we get out at the end is flexible, lightweight, and can be different shapes and colours.

All of this means we can use solar power in ways that are different to what we can currently do with existing hard, rigid silicon solar panels.This is our smallest printer. And what we can do on this is print rolls that are about 10 centimetres wide. What we’ve got here is a solution of the polymers that absorb the light in the printed solar cell. So we take this solution, this ink, and put it into the tray that’s inside the printer.

Then we run the printer, and the printer coats this ink onto the plastic. And that’s the first step in making the solar cell. So we take the rolls from the printer that we just saw that have the polymer ink printed down onto them, and we bring these and install them on this printer here.

What this printer does is puts down the top electrode, and that’s a silver grid.We can see that silver grid printed on here on the finished solar cell. So this is one of our printed solar cells. We’ve put some copper tape on the ends to act as the connector. What I’m doing here is taking this printed solar cell and plug into it the positive and negative electrodes. We’ll then take our cell and put it under our light, and we can measure how much power it’s producing.

So what we’re doing here is we're measuring how much current the solar cell is producing. Even under this room light, we’re still producing a little bit of power. But when we turn the solar simulator on that simulates the real sunlight, we see a big jump in the amount of current that we’re producing. One view of a city of the future would be that every surface is generating some electricity.So that’s the windows, that’s the tops of the buildings, the bus shelters, the roofs of the cars, and the bags and the clothing that people are carrying around and wearing.

All of us have the potential to be generating that power and having things that generate that power around us.That’s the vision of the future.

The mind-bending future of flexible electronics

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