The eureka factory

If you haven’t already heard, the solar cell efficiency race is on, and once you’ve dusted off your periodic table, it’s a race as scintillating as any big-ticket derby. The stakes, however, are much, much higher.

The scientists who are globally acknowledged to be the best at developing solar cells – tweaking them, goading them to perform better at converting sunlight to electricity – have been quietly doing their work for four decades in a laboratory at the University of New South Wales, just up the road from Sydney’s Royal Randwick Racecourse.

It’s here that the man dubbed the “Solar Godfather”, Professor Martin Green, has maintained his research team’s world record in solar cell efficiency (the percentage of sunlight successfully converted into electricity) for 30 of the past 32 years. It’s in large part thanks to these leaps in effectiveness that solar power is predicted to be the cheapest energy on earth within ten years.

In an alternate universe, every Australian would know Green’s name. The reality is that he and his team are fighting to keep their federal government research funding. Speaking at the Paris climate summit last December, Prime Minister Malcolm Turnbull lauded Green’s research, and happily took credit for the work of Australian universities “at the forefront of energy and climate science innovation”. Yet just a few months later, in March, Turnbull announced a plan to gut the early-stage research grants budget of the Australian Renewable Energy Agency’s already small pot of funding, putting at risk most of the projects that Green and his colleagues are running.

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In a conference room at the Australian Centre for Advanced Photovoltaics (ACAP), headquartered at UNSW, Green, the centre’s director and co-founder, hands me a silicon wafer solar cell.

Before meeting Green, who at 68 is still movie-star handsome, with a full head of hair and a toothy smile, I can’t say I had spared much thought for solar cells of any kind. In theory I was already a fan: what’s not to like about abundant, cheap, clean energy? But I had never wondered about what exactly goes on beneath the inscrutable glassy surface of a solar panel.

The cell he gives me is about the size of a Kindle and is mounted in glass like an awards plaque. Green keeps it on his desk to use as a visual aid when explaining the technology to science dummies like me, though to his credit he doesn’t let on if he thinks my questions are stupid. “See the wafer?” he says. “That’s all silicon. It would have broken by now if it weren’t packaged in glass like this, because it’s quite brittle. But like this it’s very durable.”

This type of silicon wafer cell is the gold standard in the industry, and has already captured more than 90% of the global solar cell market. It has kept Green company for more than 40 years, yet it’s clear he is still fascinated by silicon’s properties. “I think the whole photovoltaic technology itself is a bit magical, you know,” he told ABC TV a few years ago. “Sunlight just falls on this inert material and you get electricity straight out of it.” His working life has been devoted to squeezing more and more power out of each new iteration of the silicon solar cell, gradually adding efficiency percentage points to the previous record.

At the table with us is Chinese-Australian researcher Xiaojing Hao, 38, who is petite, wears her black hair in a bob, and laughs easily and loudly. Hao is a tenured faculty member at the UNSW School of Photovoltaic and Renewable Energy Engineering, and a rapidly rising research star thanks to her work on a different kind of solar cell, CZTS (copper-zinc-tin-sulphide), which has promising applications for building-integrated photovoltaics. She, too, has brought along a specimen to show me: a dark square the size of a Scrabble tile.

Hao moved from China to Australia in 2004 to join her husband, a chemical engineer at UNSW whom she had met when they were both undergraduates studying materials engineering at Northeastern University in Shenyang. At the time, there was much excitement about the boom in the Chinese photovoltaics (PV) industry, and when Hao came across Green’s research on solar cells, she was fascinated. She wrote him an email, asking if he would be her PhD supervisor, and was shocked – and delighted – when he wrote back the same day.

In 2006 she started her PhD with Green, who says he quickly realised that Hao is an “outstanding researcher”. After ten years working together, Green and Hao now have a relaxed relationship. “I’m very lucky,” she says. “Whenever I have questions or difficulties, I feel very free and easy to talk to Martin. He’s a kind of father, rather than a boss.”

Hao and Green explain to me why boosting solar cell efficiency has enabled the solar power revolution. The higher the cell’s efficiency, the lower the associated manufacturing, transport, land, installation and wiring costs of solar panels. More efficient cells means fewer panels are needed to generate the same amount of power. In a recent academic paper, Green cites research by one of his former PhD students, Andrew Blakers (now director of the Centre for Sustainable Energy Systems at the Australian National University), which shows that a “5% relative efficiency improvement on 50% of Australian photovoltaic systems over the ten-year period 2018–2028 … translates to savings of $750 million”.

Blakers points out that “solar PV electricity is now less expensive than both domestic and commercial retail electricity from the grid” and is “approaching cost-competitiveness with wholesale conventional electricity in many places”. In the 1970s, the cost of solar was around $100 a watt, whereas now it is 60 cents a watt.

This radical drop in cost was “the first wave of the solar revolution”, says Sven Teske, a solar industry expert at the Institute for Sustainable Futures at the University of Technology Sydney. The second wave in this revolution – which Teske says will ensure that solar PV “dominates global energy markets” – is now gathering momentum, thanks to the development of battery storage. (Australia is one of the first markets where the Powerwall, the solar battery technology made by American automotive and energy storage company Tesla, is available.) Now that solar energy can be stored and used when needed, “nothing will be the same anymore”, Teske says. “The whole sector will be put on its head.”

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In the genealogy of solar cells, silicon comes first, which feels fitting given that, after oxygen, it’s the most abundant material in our planet’s crust. Solar-grade silicon looks either futuristic or primordial, depending on what form it’s in: silvery shavings or fat, shining ingots that would make Gollum drool.

Selenium, another chemical element with semiconducting properties, was the focus of the first PV experiments. (As early as 1883, an American inventor used it to make a 3-square-metre rooftop solar panel in New York.) But progress in PV research was slow until 1941, when a scientist at Bell Laboratories in New Jersey observed, by chance, a “photovoltage” in a specimen of polycrystalline silicon (meaning it produced an electric current at the junction of two substances when exposed to light). Silicon was subsequently found to be six times more efficient than selenium. Fast-forward to 26 April 1954, when the announcement of the first silicon solar cell (at 6% efficiency) made the front page of the New York Times. The paper heralded it as the symbol of a “new era, leading eventually to the realization of one of mankind’s most cherished dreams – the harnessing of the almost limitless energy of the sun for the uses of civilization”.

“This all seemed like ancient history to me when I made my first photovoltaic cell in 1971,” Green writes in an academic paper on the history of his 40 years of PV research. At that time, solar cells were mostly being developed for use in expensive space applications. In 1974, Green started the PV research group at UNSW as a young academic after undergraduate studies in microelectronics at the University of Queensland and a PhD in Canada. Cell efficiency was at about 17%.

In the early 1980s, Green and his research team, which included Andrew Blakers, had a breakthrough when they achieved a new world record for silicon solar cell efficiency, hitting 18%. A few months later, after a small change in design, they hit 19%. By 1985, they’d achieved what Green calls the “photovoltaic 4-minute mile”: the very first 20% efficient silicon cell.

Over the years, they kept racking up the records. In 1983, Green had invented the silicon PERC cell (passivated emitter and rear cell), now the commercial standard, although it took several years to get it working well. By 1988, the PERC cell had achieved 21.8% efficiency; by 1999, 24.7%; and by 2008, 25%. By then, Green and his team had maintained their world record for silicon solar cell efficiency for decades. (I sense it was a sore point when, in 2014, a Japanese research team took that title from them. As Green writes, “Panasonic was able to inch past the UNSW 25.0% result with a 25.6% achieved for silicon cell efficiency.”)

One of the few downsides of these super-efficient PERC cells was that they were made of silicon wafers, which makes them bulky. The wafers are hundreds of microns thick, and have to be encased in glass to keep them from degrading due to environmental exposure.

As a result, from the early 1990s, there was significant research interest in a new line of solar cells: “thin-film” cells, designed to have an active semiconductor layer only a few microns thick on top of a substrate such as glass. The potential long-term applications were exciting. In theory, these more flexible cells could be made more cheaply than silicon wafer cells, and deposited not only on glass but on tiles or stainless steel, as well as on curved surfaces – bringing the dream of buildings with built-in solar capabilities closer.

In response to this interest, Green, his long-time UNSW colleague Stuart Wenham, and one of their standout PhD students from China, Shi Zhengrong, began to develop a thin-film technology called CSG (crystalline silicon on glass). Initial results were so encouraging that, in 1995, UNSW and electricity company Pacific Power formed Pacific Solar (later CSG Solar) to commercialise the technology.

In 2001, Zhengrong, who had gained management and manufacturing experience working for Pacific Solar, headed back to China to set up a new PV panel manufacturing company, Suntech Power, with several fellow Chinese-Australian colleagues. Wenham was chief technology officer. Suntech quickly and radically altered the global solar commercial landscape. Using large-scale manufacturing to bring down the cost of producing silicon wafer (not thin-film-cell-based) PV panels, Suntech rapidly become the world’s largest PV manufacturer, and Zhengrong the world’s first solar billionaire.

Soon there were dozens of Chinese PV companies, all trying to emulate Suntech’s success. As a result, in just five years, the cost of manufacturing PV panels dropped by a factor of ten. As Green writes in a recent review paper about the history of the Chinese PV industry:

By 2010, most of the world’s PV manufacturing had shifted to China along with the associated supply chain. The financing of this turnaround was almost entirely through capital and debt finance raised on the US stock exchanges (over US$7 billion involved), a funding approach pioneered by Suntech with outstanding success.

All these new PV manufacturers needed huge volumes of solar-grade silicon to make their cells, something nobody had anticipated. Suddenly high-purity polysilicon was in massive demand. The polysilicon refinement industry boomed, but due to the long lead time in getting new factories up and running, the polysilicon shortage hit the PV industry hard, driving up production costs. At the same time, a slowing economy dried up Suntech’s capital, and then the company’s Italian operations became ensnared in a financial fraud scandal that cost it half a billion dollars. By 2013, Suntech was bankrupt.

This solar-grade silicon shortage, while crippling to manufacturers of silicon wafer cell panels, created a brief window of opportunity at the start of this decade for thin-film cell technologies that did not depend on silicon (or didn’t need as much of it). During this period there were at least 12 thin-film companies with product on the market. The thin-film cells were generally still not performing that well in terms of efficiency – CSG cells, for example, had about 8% efficiency at the time – but because they did not need poly-silicon, demand was quite high. (Ten megawatts of CSG panels were installed in Germany around then, enough to power 10,000 homes.)

Yet this boom for thin-film panels was brief. As soon as the new polysilicon refinement plants came on line – turning the solar-grade silicon shortage into an oversupply – silicon wafer cells again became ridiculously cheap to make. Thin-film cell companies simply could not compete.

Today, almost a decade later, only two companies are still manufacturing thin-film solar cells in any volume, and they each focus on slightly different technologies: CdTe (cadmium-telluride) cells, which have about 5% of the solar cell market, and CIGS (copper-indium-gallium-selenide) cells, which have about 3% of the market. Both of these technologies started out at about 5% efficiency 30 years ago; now they’re at about 22% efficiency.

In terms of long-term viability and uptake within the building industry, however, both the CdTe and CIGS thin-film technologies have an Achilles heel. Solar cells need to be efficient but also cheap to make. The materials they use must be in abundant supply and – ideally – non-toxic (not only to avoid environmental impacts at end-of-life or in the case of degradation but also to keep manufacturing costs down). This is where CdTe and CIGS technologies lose their competitive edge. Selenium is toxic, cadmium is highly toxic, indium (which is used to make touchscreens) is increasingly scarce, and tellurium is as scarce as gold. All of this has, up to this point, kept thin-film cells from fulfilling their potential in a future where everything from car bumpers to stainless-steel building infrastructure could be solar activated.

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Enter, stage left, Xiaojing Hao’s version of the CZTS solar cell. Like other thin-film technologies, it involves applying a thin photovoltaic membrane to various substrates. The difference is that her iteration of this cell uses components that are abundant and non-toxic. Plus, unlike a thin-film silicon cell such as CSG’s, Hao’s CZTS cell has the potential to become much more efficient with the right modifications. It could very well turn out to be the Holy Grail for zero-energy buildings: sheets of galvanised iron or coated stainless steel used as roofing material could, cheaply and without fear of consequences from toxic materials, have an active CZTS photovoltaic layer on top.

If Green has been in the solar cell efficiency race for decades, Hao’s own race is just beginning. The CZTS solar cell she showed me only has an efficiency of about 7.6%. But things are moving fast, and her goal is to get the CZTS cell up to an efficiency comparable to that of other thin-film cells within five years. “It’s about finding the secrets of the material and how to get good performance out of it,” Green explains. “Once you get out at the front of these fields, like we did with silicon, you tend to have an advantage over the rest of the field because they’re trying to catch up with your last step while you’re thinking about the next step.”

If Hao succeeds in her goal of ramping up CZTS cell efficiency, then she and Green will start on an even more ambitious idea. They plan to layer a CZTS membrane on top of silicon cells – a bit like spreading icing on a cake – to create “tandem cell stacks”, which they believe could have an efficiency of more than 30% within ten years. This is remarkable because the acknowledged theoretical limit for silicon cell efficiency is just over 25%. “There’s no big leap in efficiency in silicon possible anymore, only incremental improvements,” Green says. But once they are able to grow thin-film CZTS cells directly on silicon wafer cells, a whole new efficiency frontier opens up.

Progress is already being made: using what is called a “four-junction mini-module”, another of Green’s leading researchers at ACAP, Mark Keevers, recently achieved a new record for unfocused sunlight-to-electricity conversion of 34.5%, a level of efficiency not previously expected to be reached until about 2050. While a stunning achievement, Keevers’ four-junction mini-module can’t easily be commercialised as it is made of extremely scarce and expensive materials generally used only in space applications. If all goes to plan with Hao’s research, however, her low-cost tandem cell stacks could revolutionise the industry.

Note down her name, because in ten years Xiaojing Hao may very well be the world’s first female solar billionaire. It’s very much part of her plan to set up her own company one day. “As a researcher in the lab, one of the dreams is seeing your own research projects applied in the real life,” she tells me. “It’s like a baby. I have been working with these cells for a few years. We started establishing the lab in 2011, and that’s also when I had my daughter. So it’s two babies!” I ask what sort of role she’d want to play in her future company. “I think chief technology officer,” she says, before giving one of her lovely, unruly laughs. “But maybe CEO, too!”

Neither Hao nor Green thinks of the Suntech saga as a cautionary tale. “Zhengrong just had a bit of bad luck,” Green says when I ask about his former student and now colleague. “Everything combined in a bad way at the wrong time. But the company had taken the industry to the next level of competitiveness in terms of costs. It would have been great to see it survive in its original mould, but it had accomplished what it had set out to do, in one sense.” Zhengrong is still an adjunct professor at UNSW, and Green believes that he would happily re-enter the commercial fray if the right idea came along. “If we got this going, he’d probably be interested in combining it with car bodies or something like that,” Green says, referring to Hao’s research. “Zhengrong’s looking for something a bit different from what he was doing, but still in manufacturing.”

There’s a lot at stake for Hao, who obviously has a deep personal investment in her research. She tells me that she never stops thinking about it, even asking her husband to take down notes if she has an idea while driving home from work. Their daughter is now five, and they also have a 14-month-old son. Hao chose to work (from home) through most of her official periods of maternity leave. After putting her children to bed each night, she gets back on her computer, and usually works Sundays, too. When I ask how she relaxes, she says that she listens to classical music while working at night. She and the research team she leads – 13 PhD students and postdocs, all male, many originally from China, and with backgrounds in chemistry, materials engineering and physics – publish their research at a fiendish pace, averaging two scholarly articles a month at last count.

Yet when I start to gush to her about the impact of her research, about how the rest of us have no idea what to do about climate change, and that I envy her going to work knowing that, even on a bad day, she is doing something with tangible environmental benefit, she looks a little embarrassed for me. Mine is a non-scientist’s romanticised view of how science works in practice, of course – I can conveniently overlook the thousands of hours she and her students have spent hunched over lab benches, the incremental progress, the frustrating technical challenges, or even the sometimes random way that scientists stumble upon the research questions they end up spending a lifetime answering.

Hao was the first in her family to go to university. She admits that her undergraduate studies in materials engineering with a focus on iron and steel production “was quite a narrow view, I hadn’t heard of PV before”. She remembers going on a class field trip to a steel company’s factories and being shocked by the “yellow emissions coming out of the chimney, the dust everywhere”. But it wasn’t until she got to Sydney and heard about Green’s work that she first thought about working in renewable energy research. Now, she says, “I see a lot of reports about climate change, what a disaster is happening in the world. I feel proud of working in this area.”

Green also subtly resists my attempts to frame his work in grandiose, world-saving terms, though he does concede that he was aware from the beginning of a sense of urgency, especially during Ronald Reagan’s presidency when funding for American PV researchers – previously supported by Jimmy Carter – dried up. He tells me that most of them had to move on to Reagan’s proposed missile-defence system, known as Star Wars. As a result, Green’s team is one of the only PV research groups in the world that has survived from the 1970s through to the present, quite a feat when you consider how the whims of politicians can swiftly destroy research budgets and priorities. “We felt we had the responsibility of developing viable technology for photovoltaics,” Green says. “We thought of it as a race against time, because we could see the demands for energy in China and India were going to grow so enormously.” It was the 1986 nuclear disaster at Chernobyl that reignited European interest in solar power, and then, in the 1990s, concerns about climate change gave PV research a new raison d’être.

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After our chat in the conference room, Hao shows me the laboratory and the sputtering machine her team uses to deposit CZTS photovoltaic layers onto substrates. Many teams working on solar cells share the lab, each with their own sputtering machines that look like space-age pressure cookers. These days Hao isn’t in the lab as regularly, though she spends a lot of time helping her students troubleshoot technical problems. When she was a PhD student and postdoc, she was in the lab almost every weekday, usually until 11 pm, and on most weekends. She looks fondly at one of the machines perched on another bench. “That machine also started work here in 2006, when I began my PhD,” she says. “I have a feeling for that machine. It has been ten years – I feel I know it, that it’s my friend.”

Think, for a moment, of all the insights Hao has had during those long hours of research, each tiny eureka moment leading to the next. These are insights that can only emerge after stretches of uninterrupted time devoted to thinking and tinkering, experimenting and taking risks. Half of the funding that bought her that precious time – first as a postdoc, and now contributing towards a major research grant for the CZTS project up to 2018 – came directly from the Australian Renewable Energy Agency. (The other half was from UNSW, the Australian Research Council, and industry partners.)

This is exactly what ARENA was established to do. The Gillard government set it up in 2012, along with the Clean Energy Finance Corporation (CEFC). As ARENA’s website states, it provides “funding grants along the innovation chain from research in the laboratory to large-scale pre-commercial deployment activities” for projects designed to reduce the cost and increase the use of renewable energy. The CEFC’s remit is to boost commercial investment in renewable energy and energy efficiency projects. Tony Abbott as prime minister tried twice to abolish these entities, and both times he was blocked in the Senate. When Malcolm Turnbull took power, the fate of these institutions remained uncertain. So after he announced in March that both ARENA and the CEFC would be spared – and that they would together manage a new “Clean Energy Innovation Fund” – the renewable energy community breathed a sigh of relief.

Soon, however, it became clear that under the new plan ARENA’s ability to issue early-stage research grants – exactly the kind of funding that Green, Hao and their colleagues depend on in order to do their research – would be revoked, $1.3 billion of ARENA’s unspent funds would be returned to consolidated revenue, and its new role would be to advise the CEFC on clean energy investments based on an equity or loan basis. John Grimes, chief executive of solar lobbying group the Australian Solar Council, described Turnbull’s changes to ARENA’s mandate as “a bit like an exquisitely decorated Easter egg … it looks good on the outside, but on the inside it’s a rotten egg”.

This sleight of hand continued during the election campaign, when Turnbull made further promises for “new” initiatives but committed no new money. The funding for these was in fact repackaged slices of the CEFC’s existing $10 billion budget: a $1 billion fund for “clean energy” and “clean water” projects along the Great Barrier Reef, and $100 million for urban “clean energy” projects.

Even more confusingly, the Labor Opposition refused to publicly commit to reinstating ARENA’s early-stage research grant funding after Turnbull’s initial announcement, and in the Senate in May, as renewables industry journalist Giles Parkinson reported in RenewEconomy, “Labor sided with the Coalition to defeat a motion by the Greens to protect the funding of ARENA out to 2022 – effectively signalling the demise of an agency it helped to create a few years ago.” Shadow environment minister Mark Butler implied it was the lack of protest against Turnbull’s new plan for ARENA from the renewables community itself that led to Labor giving up on ARENA too. “People welcomed the Clean Energy Innovation Fund, so we welcomed it,” Butler said at the time, in response to a question from Parkinson at a conference in Melbourne.

Green seems like a person who prefers to keep his distance from the political fray. (He has a droll habit of using politicians’ first names in conversation, which makes them sound like little boys up to no good: “Tony was philosophically opposed to renewables, so he just had a weird outlook on a lot of things,” or “Malcolm said ARENA was going to be saved, but the role of ARENA in giving grants to universities has disappeared.”) In his public statements, Green has shown forbearance: in a UNSW press release criticising the government for its decision to cut off ARENA grant funding, he said, “I don’t think this is a deliberate attempt to wipe out research into photovoltaics in this country – it’s more a case that the implications have slipped below the radar.”

But after Turnbull’s announcement that both ARENA and the CEFC would be spared, Green says he could still see the writing on the wall. Turnbull had promised one thing while doing another. In its new incarnation, Green says, ARENA would advise on “riskier front-end investments … rather than investing in the R&D side of things. So that could be disastrous for us.” As Ian Kay, CFO of ARENA, said in late May at the UNSW Forum on Clean Energy Finance and Investment, “ARENA, as well as looking at the here and now, has also got a view certainly out to 2030, but actually the Board thinks about what’s happening out to 2040 – and to get purely commercial private sector money to take a view over that timeframe is just really difficult.” As Parkinson reported in RenewEconomy, John Grimes agrees: “A lot of the blue sky research, the first research we might see out of somewhere like the CSIRO … you can’t make a commercial case to say, well lend me $1.5 million, I’ll pay you back $2 million in three years.”

Already, ACAP is anticipating that many of its early-career researchers will lose their jobs next year. Colleagues at the Centre for Sustainable Energy Systems at ANU (headed by Andrew Blakers) will also be hit hard, as ARENA funds half its researchers. Earlier this year, 130 researchers wrote an open letter to the then environment minister, Greg Hunt, and 62 energy researchers wrote an open letter to the prime minister to protest the ARENA decision, saying that “grant-supported renewable energy R&D and education is a crucial part of climate change mitigation, and will be seriously downgraded by this new policy”. Nobody yet knows how all this will play out once the dust settles post-election; uncertainty prevails.

Eric Knight, a senior lecturer at the University of Sydney Business School, argued in his 2011 Monthly article on Green and Zhengrong that Australian politicians often display a dangerously naive understanding of how the early stages of research-led innovation arise in practice (even if they pride themselves on their nous as innovators). Knight believes our government too often overlooks what he calls the “network theory of success”: how crucial it is for innovators to have a “tight network of supporters and collaborators” gathered around them.

This is what Green has created in his four decades at ACAP: a network with deep collaborative ties both within Australia and also across the region; a critical mass of researchers working on related projects, who can share knowledge within a trusted community. But no matter how tight that network is, or how many years it took to build, if the funding dries up, then the people within it will disperse pretty quickly. “Continuity in funding is essential in solar cell research,” Green says. “So if you lose your funding for even a year or so, a lot of your expertise disappears as teams are disbanded.”

Sven Teske from the Institute for Sustainable Futures (which also depends on ARENA funding for much of its energy-related research) agrees. “What innovation requires is freedom to think for a while and a secure environment for scientists,” he explains. “If a scientist is busy for most of the time writing funding applications, there is little time to actually do what a scientist is supposed to do: think.”

Alison Atherton, also an energy researcher at the Institute for Sustainable Futures, told me that a productive aspect of ARENA’s funding model that has been ignored in the debate so far is that any ARENA grant funding has to be matched by the institution receiving the grant, often through public–private partnerships. “ARENA costs the government money, but it also leverages money from the private sector in matching funds that wouldn’t be invested in renewables otherwise, especially for the solar industry.” According to ARENA, each dollar of its funding has leveraged about $1.50 in matched funding or co-investment from other sources.

Both Knight and Green also take issue with what they see as the misguided, nativist assumption that Australia’s PV research and innovation has been for naught because so many of ACAP’s students are from overseas, and the research produced here often gets commercialised elsewhere in the world. As Knight wrote in his Monthly article, it’s dangerously short-sighted to “see the Australian economy as being defined by its borders”.

The problem, Green says, is that “the benefits of Australia’s leadership in research and development are not always directly seen. You know they say, ‘If a Japanese company ends up commercialising this, what are the benefits to Australia?’” According to Green, this view misses the bigger picture: that it’s thanks to these Australian-trained researchers that the Asia-Pacific region was able to become the hub for low-cost manufacturing of PV panels, which has been good for all of us. “This, in turn, has been responsible for the dramatic reduction in manufacturing costs over recent years that has positioned photovoltaics as one of the lowest cost options for future electricity production.”

In May, Green published an information paper to highlight that the flow-on economic benefits to Australia from past Australian PV research are estimated to be worth well over $8 billion. This includes direct benefits, like licensing income and the billions of dollars of income from commercialisation, or spin-off companies formed by UNSW to deliver high value–added applications (for example, equipment for testing solar cells during the production stage). And then there are the indirect benefits, such as the massive boost given to the local economy via the growing PV-system installation industry. “There are benefits to the country just from using the panels, not just from making them,” Green tells me. “I mean, 3000 jobs building submarines in Adelaide for how many billions of dollars? You’ve just got to encourage people to put in solar systems and you’ll generate 10,000 jobs in installation of those systems. If the country embraced that as a strategy rather than building submarines, you’d get much more employment from it – and sensible employment. Not employment that is adding to the country’s costs, but actually reducing costs by lowering the real costs of electricity generation.”

In an academic paper Green published just before the ARENA de-funding announcement, his optimism about the future of his lab and his pride in the researchers it fosters – people like Shi Zhengrong, Mark Keevers and Xiaojing Hao – shine through: “With photovoltaics poised to become one of the largest energy industries of the future, it is hoped that, over the next 40 years, the laboratory will continue its combined role of blazing the path to future generations of technology while producing researchers able to spearhead the ongoing growth of the industry.”

Though he shows no signs of slowing down, Green is nearing 70, and he may not be around to witness all of that future – if, indeed, his lab is granted a future at all. But if he is around for the next 40 years, I suspect he will choose to spend them just as he has the past 40: back in the laboratory, egging on his researchers, and watching as the humble solar cell changes the world, one efficiency point at a time.