Researchers at the Oxford University Physics Department have unveiled a groundbreaking method that could enhance solar electricity generation without relying on traditional silicon-based solar panels. Instead, their innovative approach involves applying a new power-generating material to everyday items, such as backpacks, cars, and smartphones.

This new light-absorbing material is impressively thin and flexible, making it suitable for application on various surfaces, including buildings and common objects. By utilising a pioneering stacking technique that layers multiple light-absorbing elements within a single solar cell, the researchers have successfully captured a broader spectrum of light, thus increasing the power output from the same sunlight exposure.

Independently verified by Japan’s National Institute of Advanced Industrial Science and Technology (AIST), this ultra-thin material boasts an impressive energy efficiency of over 27%. This marks a significant advancement, matching the performance levels of conventional silicon photovoltaics for the first time. The researchers expect to publish their scientific findings later this year.

Dr. Shuaifeng Hu, a Postdoctoral Fellow at Oxford, noted, “In just five years of experimenting with our multi-junction method, we have improved power conversion efficiency from approximately 6% to over 27%, nearing the maximum potential of current single-layer photovoltaics. We believe that this approach could eventually lead to efficiencies exceeding 45%.”

In comparison, today’s solar panels typically achieve around 22% energy efficiency, meaning they convert about a fifth of the sunlight energy they receive. The versatility of the new ultra-thin material is a key advantage; at just over one micron thick, it is nearly 150 times thinner than a silicon wafer. Unlike traditional photovoltaics, which are limited to silicon panels, this new material can be applied to almost any surface.

Dr Junke Wang, a Marie Skłodowska Curie Actions Postdoc Fellow, stated, “By employing new materials that can be used as coatings, we’ve demonstrated that we can replicate and surpass silicon's performance while also gaining added flexibility. This innovation holds the promise of generating more solar power without the necessity for numerous silicon panels or specially constructed solar farms.”

The research team believes their approach will not only lower solar energy costs but also enhance its sustainability as a renewable energy source. Since 2010, the global average cost of solar electricity has dropped nearly 90%, making it significantly cheaper than fossil fuel-generated power. The development of new materials, such as thin-film perovskite, is expected to drive further cost reductions by decreasing reliance on silicon panels and dedicated solar farms.

Dr Wang added, “We envision perovskite coatings being applied to a wider variety of surfaces to produce affordable solar power-on car roofs, building exteriors, and even mobile phone backs. If we can generate more solar energy in this way, the long-term need for silicon panels and additional solar farms could diminish.”

The Oxford team, led by Professor Henry Snaith, comprises 40 scientists dedicated to advancing photovoltaics, particularly through the use of thin-film perovskite, a focus they began around a decade ago. Their work benefits from a custom-built robotic laboratory.

The commercial potential of this research is substantial, with applications already emerging in utilities, construction, and automotive industries. Oxford PV, a UK company founded by Professor Snaith to commercialise perovskite photovoltaics, has recently commenced large-scale manufacturing operations in Brandenburg-an-der-Havel, Germany. This facility is the world’s first to produce perovskite-on-silicon tandem solar cells at volume.

Professor Snaith remarked, “Although we initially considered UK locations for manufacturing, the government has yet to provide competitive fiscal and commercial incentives compared to other regions in Europe and the United States. The UK has traditionally approached solar energy through the lens of building new solar farms, but true growth will arise from the commercialisation of innovations. We hope that the newly established British Energy will focus on this.”

He emphasised, “The supply of these materials will create a rapidly growing industry within the global green economy. The UK has demonstrated its capability to innovate and lead in this scientific arena. However, without new incentives and a clear pathway to transition this innovation into manufacturing, the UK risks missing the opportunity to spearhead this emerging global industry.”