Australian researchers broke the world’s solar power efficiency record last month with their design of a novel commercial energy system, raising hopes the fossil-fuel dominated country may someday switch off its reliance on coal.
A team at the University of New South Wales led by professor Martin Green worked with a local company to create a highly efficient solar energy system that uses mirrors to concentrate sunlight onto a central solar panel to generate electricity.
The method is known as concentrator photovoltaics (CPV), and the result is a system with an efficiency of 40 percent, meaning 40 percent of the sunlight hitting the solar panels is converted into energy — the highest such level ever achieved.
Most important, the design uses readily available materials, which makes putting the system into operation easier and cheaper than trying to commercialize more experimental designs.
Green, who is also the director for the Australian Center for Advanced Photovoltaics, has a history of this kind of innovation. In 2011 he and his team built a solar cell that operated with 19.3 percent efficiency, edging out the previous record holder’s 18.9 percent efficiency.
Off the grid
This kind of innovation has become the hallmark of the solar energy industry, and it is only going to grow, according to Green.
“What’s happening now is that photovoltaics has improved so much recently that it is better at producing electricity than using hot steam,” he said. “Solar will become the cheapest way to generate electricity at any scale. The transition is going to occur where it becomes cheaper to use solar than coal.”
In the past, lower efficiencies and the risk of power outages on cloudy days meant solar was viewed with suspicion by consumers and industry analysts. But that has changed over the last five years as the cost of installing solar energy systems in Australia has been reduced.
With a huge uptick in the number of people installing solar-powered systems on their roofs, there is less demand on the power grid during periods of peak usage, such as during the afternoon.
This in turn is forcing electricity prices lower and will force a fundamental change in the way developed nations generate electricity, according to Giles Parkinson, editor of RenewEconomy, an Australian website that tracks developments in the solar energy industry.
“If you look at what the mainstream analysts are saying now, they are talking about the solar revolution,” he said. “Even the energy distributors in Australia, they are talking about the end of centralization and the rise of the microgrid.”
According to Parkinson, solar is now at “grid parity” with traditional sources of electricity. “What we’re starting to see now in Australia and around the world is that the large utilities have realized the transition is inevitable, that they can slow it down but they can’t stop it,” he said.
In Australia the solar industry is supported through subsidies such as the renewable energy target (RET), which requires the government to ensure that 41,000 gigawatt-hours of the country’s energy is produced from renewable sources by 2020.
The other function of the RET has been to promote both large- and small-scale investment in renewable projects, which helped grow the Australian renewables sector become a $20 billion industry annually.
But with a government review of the program and uncertainties around its future, large-scale investment in renewable energy projects such as wind farms has ground to a halt.
While no government decision has yet been made about the future of the RET, the uncertainty it created effectively caused the bottom to fall out from the industry, slowing its growth.
Meanwhile, smaller-scale investment — such as rooftop solar systems — has so far escaped the same fate, as consumers who install such a system could receive an upfront payment.