Over the past decade, the cost of converting sunlight to electricity has dropped by more than 90%. Solar energy is today the cheapest form of electricity generation in new buildings.
is the work done? not exactly. Solar energy currently works well, is reasonably priced, and can greatly help reduce emissions. But with less than 5% of the world's electricity coming from solar, we are only at the beginning.
The solar cells of 2022 will resemble the huge cell phones of the 1990s. Much more is possible with the same core technology.
Australia is likely to play an important role in global progress. We have been at the forefront of the development and dissemination of solar energy technology for decades. We have achieved record performance for silicon solar cells in 30 of the last 40 years. We now have more solar power per capita than any other OECD country and supply around 15% of our electricity demand. Over 80% of new solar panels in the world are based on PERC cells, a technology developed in Australia.
So what are the prospects for solar energy? Hundreds of researchers in Australia have focused on two goals: further reducing costs and generating most of the electricity from sunlight.
Why should the sun get better?
Solar energy has the potential to transform our industry, our transportation and our way of life if we push the technology as far as possible.
Extremely cheap electricity opens up enormous possibilities: from the transformation of water into green hydrogen for energy storage or use in industrial processes, to the electrification of transport, power systems and everything in which we use fossil fuels .
Last year, the Australian Renewable Energy Agency outlined its vision for ultra-affordable solar. The goal is ambitious but achievable.
The agency wants the efficiency of commercial solar panels to reach 22% to 30% by 2030. It wants the total cost of a large system (panels, inverters, transmitters) to drop from 50% to 30 cents per watt.
This will require extensive research. More than 250 Australian researchers are working towards these goals at the Australian Center for Advanced Photovoltaics, a collaboration between six universities and CSIRO.
Can silicon really keep giving?
Solar cells convert sunlight into electricity with no moving parts. When sunlight hits silicon, the material commonly used in solar cells, its energy releases an electron that can move around the material, just like electrons move in wires or batteries.
The solar panels on your roof probably originated as desert sand, which transformed into silicon dioxide, then transformed into silicon and purified again to produce 99.999% pure polysilicon. For decades, this versatile material has been at the heart of solar energy success. Most importantly, it is scalable, from the size of a pinhead to arrays that span square kilometers.
But to get the most out of the sunlight hitting these panels, we need more than just silicon. We cannot achieve 30% efficiency with silicon alone.
Learn more about Tandem Cage - Sun Sandwich. Since silicon can absorb up to 34% of visible light, researchers are focusing on adding layers of other materials to capture different wavelengths of light.
Peravskite is an option. These family materials can be compressed or coated with liquid springs, making them inexpensive to machine. When we put this material on top of silicon, we see a huge leap in solar cell efficiency.
While the possibility that perovskite will persist beyond the 20 years we expect from silicon sheets is promising, there are still challenges to be solved.
Researchers are also looking at other materials, such as polymers and chalcogenides, a common group of minerals including sulfides that promise thin, flexible solar cells.
Any new material must not only do well in converting sunlight into electrons, it must be abundant in the earth's crust, cheap, and stable enough to guarantee a long life. For example, chalcogenides are made up of common elements such as copper, tin, zinc and sulfur.
If we can achieve 30% efficiency, we will make big profits. The cost of setting up a large solar park will be reduced. You need fewer panels and less space for the same energy as more efficient solar cells.
It will also make fossil fuels more competitive. Coal-fired car engines have an energy efficiency of around 33-35%, which means that most of the energy contained in fossil fuels is lost in the form of heat and noise. You also have to pay to ensure sustainable fuel. Once the station is installed, solar panels and wind energy cost nothing.
How can we further reduce costs?
Currently, new solar power in Australia costs A $ 50 per megawatt hour. (The cost of coal is approximately $ 100 / MWh.) This is in line with CSIRO 2021-22 energy cost estimates.
By 2030, our Renewable Energy Agency wants to reduce the price to just $ 15 per megawatt hour, or 1.5 cents per kilowatt hour. At this price, storage solar power will provide affordable and reliable electricity 24/7.
As solar cells become more efficient, modules last longer and we find cheaper ways to produce and implement solar technology, costs will decrease.
Ultra-cheap solar energy will be transformative, enabling Australia to create new opportunities in existing and emerging sectors such as converting hydrogen and ammonia into fuel sources, processing clean steel and aluminum, and even processing silicon itself. It can make more solar panels.
Even with current technology, the demand for solar energy is expected to double and double over the next decade. This means knowing how to make the solar energy industry sustainable and how to recycle solar panels when the first solar panels reach the end of their life and need to be refurbished.
An Australian innovation started the solar boom. As climate change intensifies and the need for locally produced clean energy increases, a sun-kissed nation once again can help accelerate the world's transition away from fossil fuels. 
Renate Egan, Professor, President, University of New South Wales, Australian Center for Advanced Photovoltaics, University of New South Wales, Sydney
This article was republished by The Conversation under a Creative Commons license. Read the original article.
