A newly developed material may be about to revolutionize solar energy. Created using what the researchers call a “multi-junction” approach, the material is already more efficient than many traditional solar panels – while simultaneously being thin and flexible enough to be incorporated into everyday objects.
As the scholars Flansburgh and Linnell famously explained: "The sun is a mass of incandescent gas; a gigantic nuclear furnace". As such, it’s a huge, and we mean huge, source of power, delivering approximately 44 quadrillion watts – the equivalent of the output of 44 million large electric power plants – to the Earth’s surface every year.
Harnessing this energy as a renewable power source is, therefore, an obvious move. In practice, however, things are more complicated: giant solar farms may be good for the climate, but they’re often bad for wildlife, reducing biodiversity and sometimes even replacing natural ecosystems such as forests.
So far, though, other options such as roof-mounted solar panels are less powerful and more expensive, leaving giant solar farms the only option for harvesting the sun’s energy efficiently. At least, until now – because, with this new innovation from the University of Oxford, we might be about to see a dramatic shift in how we can collect solar power.
“By using new materials which can be applied as a coating, we’ve shown we can replicate and out-perform silicon whilst also gaining flexibility,” said Junke Wang, Marie Skłodowska Curie Actions Postdoc Fellow at Oxford University Physics, in a statement on the development. “This is important because it promises more solar power without the need for so many silicon-based panels or specially-built solar farms.”
Essentially, the team has created a material that combines the trifecta of solar-harvesting properties: it’s cheap, it’s efficient, and it’s eminently usable.
Built up from multiple light-absorbing layers, the new material can harness a wider range of the light spectrum, making it extremely efficient by solar technology standards. Indeed, it has already been independently verified to deliver more than 27 percent energy efficiency – which may not sound a lot, but it’s “close to the limits of what single-layer photovoltaics can achieve today,” explained Shuaifeng Hu, Post Doctoral Fellow at Oxford University Physics.
But Hu believes this early success is just the beginning. “During just five years experimenting with our stacking or multi-junction approach we have raised power conversion efficiency from around 6 percent to over 27 percent,” he pointed out. “We believe that, over time, this approach could enable the photovoltaic devices to achieve far greater efficiencies, exceeding 45 percent.”
At the same time, however, the material is thin – a mere one micron thick, almost 150 times thinner than a silicon wafer, the statement reports – and flexible enough to apply to the surface of almost anything, from buildings and roads to even backpacks or mobile phones.
Such innovations “could become a platform for a new industry,” suggested Henry Snaith, Professor of Renewable Energy at Oxford University Physics Department, who led the project; “manufacturing materials to generate solar energy more sustainably and cheaply by using existing buildings, vehicles, and objects.”
This spread of solar harvesting into the everyday is an idea that has proved popular in recent years: we’ve already seen concrete that can power your car as you drive on top of it, and we theoretically have everything we need to build a solar power-generating house, windows included. With solar power growing ever more efficient – and increasingly, much cheaper than fossil fuel energy – some experts now believe a solar-powered future is now all but inevitable.
“Thus far the UK has thought about solar energy purely in terms of building new solar farms, but the real growth will come from commercializing innovations,” Snaith said.
“Supplying these materials will be a fast-growth new industry in the global green economy and we have shown that the UK is innovating and leading the way scientifically,” he added. “However, without new incentives and a better pathway to convert this innovation into manufacturing the UK will miss the opportunity to lead this new global industry.”