Two problems seem to be plaguing the planet and our survival as a species – the ever growing mass of plastic waste we produce, and our dwindling supplies of fossil fuels. But surprisingly there could be one solution that solves both problems at the same time. And even better – it’s solar powered!

Researchers at the University of Cambridge claim that they have created a machine that takes CO2 as well as plastic waste and turns it into fuel using solar power. Their “Photoelectrochemical” system uses two compartments inside a reactor, one for greenhouse gases, and one for plastic waste. A light absorber called Perovskite and a chemical catalyst are then used to absorb enough light from the sun to convert the waste into carbon, a basic fuel.

“What’s so special about this system is the versatility and tunability — we’re making fairly simple carbon-based molecules right now, but in the future, we could be able to tune the system to make far more complex products, just by changing the catalyst,” explained Cambridge chemist Subhajit Bhattacharjee.

“Generally, CO2 conversion requires a lot of energy, but with our system, basically you just shine a light at it, and it starts converting harmful products into something useful and sustainable,” added coauthor Motiar Rahaman.

As well as carbon based fuels, the Photoelectrochemical system was also able to convert plastic bottles and CO2 into synthetic gas, and glycolic acid. Synthetic gas is an important part of liquid fuels.

On a side note, the Perovskite and catalyst combination could also help transform the solar power industry by making solar panels more productive and efficient in converting sun light into power.

But they’re not stopping there. While the system would be valuable in removing waste products from the planet and at the same time creating a fuel, the team at Cambridge believe that within the next five years they will be able to adapt the Photoelectrochemical system to transform other, more complex, materials and possibly create a solar recycling plant.

“Developing a circular economy, where we make useful things from waste instead of throwing it into landfills, is vital if we’re going to meaningfully address the climate crisis and protect the natural world,” explained Professor Erwin Reisner, a scientist at Cambridge’s Yusuf Hamied Department of Chemistry. “And powering these solutions using the sun means that we’re doing it cleanly and sustainably.”