Sunshine science: the power and peril of the sun’s rays

Summer is on its way, and this week we're exploring both the power and the peril of the sun. First, we visit the Ultrafast Laser Lab to learn about efforts to create better solar panels. Then, we hear about one professor's quest to teach kids about sun safety using an ultraviolet dosimeter you can wear on your wrist like a watch.

The sun, our closest star, is an incandescent ball of plasma powered by nuclear fusion, flinging energy off into space. As Earth's tilted orbit brings the southern hemisphere more into the sun's direct glare (summer is coming!), we bring you two stories about harnessing that energy and protecting ourselves from its harm.

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New solar power materials

A long bench wraps around a laser at the centre of the room. It's crammed full of lenses, mirrors and prisms - the tools of the trade for a scientist investigating the physics of materials, like Dr Michael Price.

Here at the Ultrafast Laser Lab at Victoria University of Wellington's Kelburn campus, Michael runs tests on different materials, as he tries to find the next breakthrough for better, cheaper and more efficient solar power.

The quest to harness the sun's energy began in the mid-1880s with the discovery of the photovoltaic effect. Today, it has advanced to the large, crystalline silicon solar panels we see on roofs. But there's a limit to the efficiency of these silicon solar panels, and Michael wants to take it the next step.

"If we could harvest more of the infrared, more of the ultraviolet, that would be one way that we could up that efficiency limit. And some of the materials we're looking at can help with that," he says.

In particular, Michael and his colleagues have been studying an organic molecule called Y6, which he thinks might be the key for that next breakthrough.

Teaching sun safety

While we can harness the sun's rays to provide renewable energy, those same rays can be dangerous if they're directed at our skin instead of solar panels.

Exposure to the sun's ultraviolet (UV) rays can lead to skin cancer like melanoma. New Zealand's rates of melanoma are among the highest in the world and in 2020, Aotearoa had the highest death rate from melanoma out of any country.

Already this year, UV level readings are higher than normal, possibly due to the Tongan volcanic eruption in January.

For a nation that loves to get outdoors and soak up the sun, we need to get smarter about our sun safety. …

Go to this episode on rnz.co.nz for more details