Tech Insights

Solar-powered Reactor: A Game-changer for the Circular Economy

February 10, 2023 by Claire Turvill

An industry first, a solar-powered reactor from a University of Cambridge research team, promises to reduce plastic and greenhouse gas pollution by simultaneously converting them into sustainable fuels and other useful products.

The circular economy is an economic model gaining traction to promote sustainability. In a circular economy, resources are used for as long as possible, extracting their maximum value before recovering and regenerating them. This contrasts with the traditional linear economy, where resources are extracted, used, and discarded as waste.



The circular economy is gaining traction as a way to promote sustainability. Image used courtesy of the University of Cambridge


By embracing the principles of the circular economy, we can reduce our reliance on finite resources, decrease waste and pollution, and create more resilient and sustainable economic systems.

University of Cambridge researchers have developed a hand-held solar-powered reactor that transforms plastic waste and greenhouse gases (GHG) into different products that are useful for various industries. This conversion supports the introduction of typically environmentally-harmful products into a circular economy; the research team hopes it will help the world shift towards sustainable green energy.

Professor Erwin Reisner (left), Subhajit Bhattacharjee (middle), and Dr. Motiar Rahaman (right) with their solar reactor. Image used courtesy of the University of Cambridge


This system is the first time the simultaneous conversion of two waste streams into two separate chemical products has been achieved using solar power.

The prototype has one compartment for plastic and one for greenhouse gases and uses a light absorber based on perovskite. Perovskite solar cells (PSCs) are a new class of photovoltaics that have shown remarkable efficiency improvements over the past few years.

Using a variety of catalysts, carbon dioxide can be converted into three different renewable fuels: carbon monoxide, syngas (synthetic gas, an important component of sustainable fuels), and formic acid (a liquid energy carrier). Under normal temperature and pressure conditions, polyethylene terephthalate (PET) has been successfully converted into glycolic acid‒an ingredient in cosmetics.

Professor Reisner, the lead author, said the team has previously been working on simpler systems that convert plastics into hydrogen, but combining the two conversion processes is the first time they’ve been able to create fuel from carbon dioxide.

The solar-powered reactor produces the end product much faster than typical photocatalytic carbon dioxide reduction and operates with significantly less energy.

All members of the research team agree that this new system could address growing pollution concerns and make progress in the development of a circular economy.

Previously, no technologies were available to create high-value end products with specificity and efficiency. What makes this reactor so promising is its adjustability; changing the catalyst could create more complex products as the system advances.

The team aims to improve the design over the next few years by creating high-energy-density fuels and various commodity chemicals to meet industry standards and needs, such as alcohol, kerosene, and gasoline.

Additionally, there is the potential to explore the use of this technology in industrial settings. Developing a recycling facility using similar solar-powered techniques would not only help to address the global plastic pollution crisis, but it would also contribute to the shift towards a more sustainable and circular economy.

The reactor and related technology has a promising ongoing impact on the energy and chemicals industry and support a greener and more sustainable future.