ABC News In-depth profiles Martin Green, a University of New South Wales researcher who spent over 50 years working on solar cell technology and, in the process, built the foundation that modern solar manufacturing sits on. He is 77, more or less retired, and tends to spend time near his local beach in Sydney. Most people have never heard of him, and there is a direct reason for that.
In 2004, installing 1 gigawatt of solar capacity took the entire world an entire year. Recently, there have been single days when that much was installed before sundown. In 2024, roughly 600 gigawatts of solar capacity were added worldwide, a figure more than ten times the size of Australia's main electricity grid. Solar is now the cheapest source of energy in the world and is on track to overtake wind as the primary source of clean electricity globally. None of this would have happened the way it did without Martin Green.
His key contribution was PERC cell technology, which stands for Passivated Emitter and Rear Cell. The standard solar cell converts sunlight into electricity by moving electrons through silicon when photons hit it. Green's design adds a reflective layer to the back of the cell so that electrons that would otherwise escape get bounced back through the silicon for a second shot at generating current. It is, as the video explains, a bit like getting a double shot from the same coffee. His laboratory at UNSW held the world record for silicon solar cell efficiency for 31 consecutive years, from 1983 to 2014.
The path from a small university lab in Sydney to solar panels on rooftops across the world ran through China. One of Green's PhD students, who came to study with him after China began sending students abroad in the reform era, took what he learned back home and founded China's first commercial solar panel manufacturing company. He was the first private Chinese-based company to list on the New York Stock Exchange in 2005, and became the first solar billionaire overnight. That opened the floodgates. Chinese manufacturers competed fiercely, drove prices down by a factor of roughly 100, and built manufacturing capacity that now exceeds 1 terawatt per year.
Green chose to publish his research rather than file patents. That decision is the reason the solar industry scaled the way it did, and it is also the reason most people have no idea who he is. There is no solar equivalent of Elon Musk at the University of New South Wales. His work contributed directly to improving cell efficiency across the industry, which reduced cost per watt, which enabled the scale that made solar cheap enough to be the default energy source it is today.
Green says he was considered too optimistic when he gave talks about solar's future. Just about every projection he made has since been exceeded by reality. He expects solar to become the dominant source of electricity worldwide, and thinks Australia will lead the way in making that happen.