Welcome, everyone to 100 Climate Conversations. Thank you for joining us. I’d like to acknowledge the Traditional Custodians of the ancestral homelands on which we meet today, the Gadigal people of the Eora Nation. We respect their Elders past, present and future and recognise their continuous connection to Country. Today is number 98 of 100 conversations happening every Friday. The series presents 100 visionary Australians that are taking positive action to respond to the most critical issue of our time, which is climate change. We are recording live today in the Boiler House of the Powerhouse Museum. Before it was home to the museum it was the Ultimo Power Station. Built in 1899, it supplied coal fired electricity to Sydney’s tram system right up until the 60s. In the context of this architectural artefact we shift our focus forward to the innovations of the net zero revolution. My name is Paddy Manning, I’m an investigative journalist and author of a book [called], Body Count: How Climate Change Is Killing Us.

Thomas Maschmeyer is a professor of chemistry at the University of Sydney, where he established and leads the Laboratory of Advanced Catalysis for Sustainability and served as founding director of the University’s Nano Institute. In 2020, Maschmeyer was honoured with the Prime Minister’s Science Prize for Innovation, Australia’s top prize in the field. Maschmeyer is the founder and director of Gelion Technologies, a battery company known for its advancements in sustainable energy storage. We are so thrilled to have him join us today, please join me in welcoming Thomas. Thomas if we can start at the beginning, you were born in Germany, studied chemistry. What drove your passion for science?

Well, already from an early age, I’m told [from] age three, I would be playing with colours on the windowsill, you know, making little experiments, see what would happen. And somehow that curiosity about coming up with a little experiment and working out what will happen and trying to predict it, that just always was fascinating for me.

You grow up in Germany, it’s an engineering powerhouse as a nation, manufacturing permeates the culture.

That’s right. So, when I when I grew up, and in Germany the weather is not always as wonderful as it is in Australia, there were channels devoted to helping the nation understand how things are actually made. Channels around manufacturing, done for children to some degree. And so, I grew up knowing where toothpaste comes from or how Coca Cola bottles are made, etc. And it was fascinating the amount of automation, the whole sophistication of that sort of operation. So, that was always very interesting to see.

When did you first realise the gravity of the climate change problem? And can you tell us, by the way, what are the ten green principles of chemistry?

Well I don’t know whether I got all ten. But certainly, when I was 11-12, I was starting to already think, well, people talk about growth, growth, growth all the time. In Germany, that was always a big thing because we were the export record holder, etc, it was West Germany at the time. And I thought, well, at some stage things are going to run out and so we need to recycle. So, I had this idea of putting Coca-Cola cans and beer cans and crushing them and making houses out of them. Because I saw then, a little bit later in fact, a documentary about South African townships where they were doing that. So, that somehow was in there all the way. And this realisation, we only have one planet, and we need to use it really carefully because we will run out of space, we run out of materials and with all the people coming along and the Club of Rome was still quite topical at the time, those discussions. So, that was always there.

The ten principles, I mean, they are all about doing these sorts of things. So, they are about doing chemistry that is safer, that doesn’t use toxic chemicals, that tries to reduce the energy used that is highly efficient and what we call the atom use. So, how many atoms go into a reaction and how many atoms go out as product versus how many go out as waste. That’s four, but I’m sure there are six very worthy additional ones.

Are the principles of the circular economy kind of reflected in those green principles?

Yes. So, designing products for circularity is one of the key elements because that’s something we haven’t really been used to. We’ve been designing products for profit, which is fair enough. But now as we are hitting global limits, we need to really think about designing them from the beginning to be a circular product. Large companies are starting to talk that language as well. They’re going to be custodians of that product across its lifetime – they make it, they sell it, they collect it again, reuse it and have a circular economy in terms of the materials used as well.

What was your early research?

My early research: I studied in Sydney, I met a wonderful Australian wife and so that brought me from Germany to Australia. My interest was catalysis in the early days and that is making chemical reactions go faster. So, I did a lot of fundamental work around that and worked out how bonds are made, how they’re broken, how I can selectively accelerate one kind of bond-making/bond-breaking versus other ones which are not accelerated, which gives me the high selectivity. So, if I have, for example, ten different reactions that are all possible in the soup and I put a catalyst in that just accelerates one and that’s the one I want. And I accelerate it by a factor of 1000 or 1 million, although the others still occur, they’re basically meaningless. So, I’m accelerating for selectivity and our body has around 30 trillion enzymes and each of those enzymes does their job in our body. That’s why we are so efficient as a biological machine, if you will. Once those enzymes don’t work, those bio catalysts don’t work. Even small amounts don’t work, you have major disease or die. So very, very important.

In 2003, you were selected for a Federation Fellowship as one of 20 overseas scientists to come to Australia as part of what then Science Minister Brendan Nelson described as a brain game. What difference did –

They must have made a mistake with me then!

What difference did that fellowship make?

Oh, huge, huge difference. So, I was at the time at the technical university in Delft and I sort of became their version of a dean. I was starting to be already quite heavy in administration and so forth. And I thought, well, I’m only 30 something, 38, I think, at the time, and do I really want to do that for the rest of my life? So, I was thinking, maybe not. The university contacted me to say, hey, if you want to come, we will support you. That sounded pretty good. And so, I was given a wonderful new laboratory, partially funded by the university, partially funded by the government, very competitive salary, etc. But what it really did was it allowed me to take risks. Because I was funded for five years. No teaching, no administration, new laboratory. I could just take risks and if it all didn’t work out, I was at the top of the tree. So, I would fall down a bit, but I wouldn’t necessarily smash to the ground and have no career. If you can take big risks, well, good things can happen. In my case, fortunately, a couple of those risks paid off.

Well, at the risk of getting my terms wrong, I understand one of your first big breakthroughs was a technology for turning cellulosic fibre into a biofuel that led to…you tried to commercialise that, as I understand, with a group of investors in the Australian Biodiesel Group. Is that right?

That’s right, yes.

What was that story and what was the breakthrough?

So one of the things was that I was asked to help a group called Australian Biodiesel Group with biodiesel, which came made out of waste fats, you know, things that come out of a deep fryer and get sucked out of the waste bins from restaurants, etc. That’s first-generation biodiesel. And that worked really well, 80 million litres-a-year production facility, etc. I helped them to reconfigure the reactor. And that reactor then became five times smaller to do the same job so that was good. But then the regulation around biodiesel, the excise for bio-anything changed under John Howard and on Melbourne Cup racing day they announced they’re going to change it such that there was no benefit of biodiesel versus normal diesel. That killed the industry overnight. So, what do you do? Okay, you sort of get up, dust yourself off and think, what else can I do? One of the other elements of why that industry failed was the feedstock price became really expensive because there was a period of time where a barrel of oil was about $150 or $180 a barrel or so. So the feedstock price of this waste oil became also really high. So, no excise advantage and a really high feedstock cost killed it. So, then I thought, well, my reactor, I could actually use it to take something which nobody likes, which is brown coal. Everybody hates brown coal, but it’s $7 a tonne. How good is that? So, I could take the reactor and make the brown coal into oil and then that oil I could sell, do good things with it. That’s how we started a company called Ignite Energy, Ignite Lignite you know, get it?

I get it. Coal to liquids, basically.

That’s it. Coal to liquids. But then we found out that the methanol we were using for the fats was too expensive. So, we did water and then we made a black coal powder that’s used in steelmaking and crude oil. And it worked technically, perfectly, really, really good. But around that time, it became impossible to do anything new with brown coal. It became societally unacceptable, whether it was here, in Victoria, New Zealand, Canada, Europe.

Germany’s got a lot of brown coal.

Germany had a lot of brown coal, and it would have been perfect for them to transition because they import black coal for steelmaking. They imported oil, so they could have stopped importing and make their own from their own resource where there was a huge infrastructure mining that resource. But although technologically sensible and everybody said it was the right thing to do economically, really good, politically impossible. People said if we do that, we will be voted out in the next election, so forget about it. So, that was the uniform echo we got from the world. So, then I thought, right so brown coal, that sort of ancient biomass and what about modern biomass? Just take a tree. So, we adopted the process to generate oil from trees, from woody waste, and that was the initial breakthrough. And then from that woody waste, we were able to make jet fuel, for example.

So, when you talk about a reactor, I understand you’re talking about the catalytic hydrothermal reactor, is that right? So, that’s using the catalysis research that you have done before. Can you explain how that works? That hydrothermal reactor.

So water comes normally in three versions. Ice, liquid water and steam. And then there’s a fourth one called supercritical water. And that supercritical water is gas. That’s just steam that is so compressed that it forms a new phase and that compressed gas is supercritical water and it’s able to dissolve oil, but it cannot dissolve salt. So, it’s the opposite. It happens at a high temperature, 378 degrees and a lot of pressure, 200 bars or so. So, to give you an idea, in a big fire engine truck, the pressure in the car tire is around 8 bar. So, we have about 200 bars. So, a lot of pressure, a lot of heat, but that’s when that happens. We then added some bits and pieces to the biomass waste, the catalysts, to help to deoxygenate it. If you look at a piece of wood, 50% of its weight is oxygen. I can’t do anything with oxygen, so I need to get that out. So, we reduced it down to about 11% by weight. And if you think about olive oil, that’s about 13% by weight. So, we got it quite oily and then that has been shown to be able to be used as a basis to make jet fuel, for example, sustainable aviation fuels.

And the cellulosic fibre, what is that? That could be anything?

That can be anything. So basically, our kicker application is to go in with pulp and paper mills where there is a lot of waste. Only about 30% of the tree becomes paper. The rest is waste of certain types, and they use that waste to burn it and as process heat to boil off some of the processing liquor and recover some of the pulp and chemicals. We can use some of this liquor in our process to start off with and integrate and take that waste. And rather than boiling it – it’s wet wood. Now, if you have a campfire and you put a wet stick on it, it’s just terrible. The temperature goes down, it’s smoky. So, it’s not a good way to use it efficiently. We can use all of that carbon in the waste and make these renewable fuels from them. And that integration works really well. So, anything bio we can use, whether it’s a leaf, bark, a tree, you know, a corn stover, the gas from sugar cane.

And then you’ve worked out how to use plastic waste? In the same process?

Yeah, a similar process. So, in the biomass we are actually not going supercritical, but it was called subcritical. It’s when this phase change is just about occurring, but not quite. And that’s special for chemical reasons. It allows us to break carbon oxygen bonds because we’re going to want to get rid of the oxygen. Now, for plastics, you don’t want to do that. You want to go and break carbon-carbon bonds. Plastics are just long chains of carbon atoms strung together, just like hair made out of carbon atoms, long chains. So, we need to cut that somehow. You cut that by heat and the chain links they vibrate so much because it’s hot, hot, and at some stage it breaks. And that’s how we liquefy it. So, that is a much higher temperature than what we used for the biomass. So, we had to adjust the process. But that’s working really well. And really it was done in response to China saying we will not take the world’s plastic rubbish anymore. We will only take it if it’s sorted to a very high level of specificity. That sorting becomes so expensive, there’s no point selling it to China. So, suddenly there was a huge amount of end-of-life mixed plastics available. Then we said, okay, here’s an opportunity. So, we went for that in 2015.

And is it in use anywhere?

Yes.

So plants, I understand, under development in Victoria and Canada?

So, starting off with the biomass, there is a plant that we are in the process of putting together in Queensland to interact with the gas. And in Canada at Prince George and the world’s largest sustainable wood-based pulp and paper factory, 6 million tonnes of wood a year. So, we’re going in there for initially 50,000 tonnes a year and then going up to 600,000 tonnes a year of waste. So, that’s the biggest sustainable fuel factory in the world then. And for the plastics that’s taken off even more. So, we have the biggest chemical companies and the biggest plastic-making companies in the world saying your technology is the technology, and they all bought licenses and [are] building plants around the world. So, in South Korea, LG Chem; and in Japan, Mitsubishi Chemical; in North America, Chevron Philips; around the world, Dow, which is the biggest company of all in this space. And they committed to six plants – building one in Germany. And then we have our own one in the UK. We’re trying to put a project together, and it’s looking pretty good, for Geelong in Australia as well. On the plastics.

What are the climate implications of plastic use and the potential benefits from reusing it as oil?

So plastic is a fantastic material because it’s light. It’s cheap. It’s hygienic. Light is really important. Because if I replace everything with glass then my trucks that are transporting things are basically transporting the weight of the glass, not so much what’s inside the glass. Recycling glass happens at very high temperatures. You’ve got to melt it down. You got to faff around, unless you can simply wash it which at a certain point you can’t anymore. So, plastic is really good. But the issue is what to do with it at the end of this lifetime.

I’ll just stop you there. Most people, I think, would be shocked to hear a scientist say plastic is really good.

Yeah but think about Covid. All the masks, all the sanitation gear. Think about any kind of hospital operation. Without plastic, it would be terrible.

It has become a major problem for the planet, though, now, hasn’t it?

It has, because there hasn’t been a way to deal with the mixed end-of-life plastic. But we’ve got the solution, and we have the industry endorsement around the world. So basically, it’s now a matter of timeline, of investment to get the plastic back into the materials chain. We just had a report from the European Union, so [they are] independent of us, and they looked at all the plastic recycling ways and they announced that we were at least 50% better than the next technology down in terms of global warming impact. So, it is the way.

What is that? How big is that impact if we could recycle more of our mixed plastic waste.

So we use about 15% of the plastic energy. So, the energy that’s in the plastic to drive the factories. So, we burn 15%, if you will, but we get 75% back. So that’s a very, very significant element. But what’s even more significant is the fact that the plastic waste now has value. You know, you can appeal to the nobility of people, right? And say you shouldn’t do this, you should do this. You should be sorting. But you go anywhere in South-East Asia and, you know, the rivers coming out are full of plastic waste because plastic has no value. If I give value to the plastic because the stuff that is at the moment not recyclable and it becomes something I can collect and put to a local deposit and I get some money for it. Boy, I think human ingenuity will start to find, on a very local level, ways to come up and collect plastic. Then the environmental impact of waste plastic is reduced very dramatically. And top of it, of course, we have the energy and the material recycling element as well. But I think the fact of the value of the waste, that’s the main impact.

Do you think this will be the killer application of your catalytic hydrothermal reactor technology?

Well both. So, the plastics are one and then, you know, you cannot fly large aeroplanes on anything other than liquid fuels. But wouldn’t it be nice if that was zero net emissions? So that’s what we are doing. And just New South Wales, for example, has got 3 million tonnes of building waste. So, you know, pallets from building sites, fences, all sorts of things and they are not recyclable because they tend to be covered with a bit of paint, some plastic sheeting on it, all sorts of things. So, they go into landfill or are burned but then you need to have very, very sophisticated exhaust cleaning. So basically, they go to landfill. So, we can take all of that and make it into sustainable aviation fuel. So that is another really big impact.

Well, this technology, as I understand, was a key reason why you won in 2020, the PM’s Science Innovation Prize. So, the other technology for which you were awarded the PM’s Science Innovation Prize was a new gel-based zinc bromide technology for a better battery called Endure. Tell us about that. What was that innovation?

Yeah, so that innovation and here it becomes really important to think about fundamental science and just walking up that mountain because it’s there, because the whole idea was based on a spectacularly unsuccessful experiment five years before. I was making a membrane to separate two drug molecules based on their chirality. So, you have left handedness and right handedness in molecules of certain types and you can’t superimpose them. So this membrane was supposed to separate the left hand from the right hand. It was a spectacular failure. However, I had it in the back of my mind because when we tried to rescue the project, we just separated two colours and it sort of did it – ish. And I thought, well, those colours are separated in the base of charge. Maybe one of these days I could do something with that. So, then I came across a company called Red Flow that did zinc bromide chemistry and a flow battery, putting electrolytes and pumps and things. I thought, well, their problem I could actually address by changing it to a non-flow system where I just have a battery that looks like a car battery because a gel will determine where things move inside the battery. That was the beginning of it. And with that, then, one had performance benefits in terms of temperature. I could go down to a very low temperature, -20, -25 or plus 50, plus 60 without the battery degrading. And all other battery technologies degrade, dramatically.

Okay. Can I now just stop you and ask, how do batteries actually work? What is the job that all batteries are doing?

Yeah. So, all batteries, no matter what they are, are based on chemical reactions. What are they? They are actually the movement of electrons. You move electrons from one chemical to another and back, bond making, bond breaking. The bonds are electrons between nuclear, between sulphur and then hydrogen or whatever. And so, what a battery does, it’s a really clever little thing. It separates out the movement of the electron from the movement of the chemical. So, the electron goes out one of the electrodes through your light bulb and then back into the other electrode in the battery.

Which one does it go out, positive or out negative?

All depends on whether you charge or discharge, so let’s not go there. And then to balance it, the chemical moves from one side of the electrode to the other side of the electrode inside the battery. So, a chemical will move inside the battery and the electron moves outside of the battery.

Through a new device.

That’s it. So that’s what every battery does. And then when you recharge it, you do it the opposite way.

What’s the gain? What’s the benefit from better energy storage technologies in the big picture? What’s the role of better batteries in the transition to renewable and cleaner energy as part of the effort to tackle climate change?

So clearly we need to decarbonise because climate change is real and although the gas is unseen, Tony Abbott, it sort of does stuff! So we need to do that. We need to firm the wind and solar. We need to back it up and we need batteries for that as one of the main elements in doing it. So that helps to decarbonise the grid. That’s a really, really important thing. Another thing is we can generate in a distributed fashion. So, I can have small generation all over the place, and I don’t need large infrastructure to send my electricity from one place to the other. I can make it locally and I can use it locally because batteries will be the storage medium to supply that energy when the sun doesn’t shine, and the wind doesn’t blow. So, a distributed system is inherently significantly more resilient than a few really big ones that distribute out, whether it’s a natural disaster, terrorist attack, plane dropping on it or whatever.

In September, the Climate Minister Chris Bowen and Science Minister Ed Husic helped launch a new plant in Fairfield to manufacture the indoor batteries. Have you had much support from the federal government?

Yes. So, it was wonderful that they both came and we’re very grateful for that, of course. That was the first manufacturing in a commercial setting. So, we made 3000 batteries of the size of car batteries. So far our main benefit has been, other than the university interaction as such where we pay for services and access, has been the tax R&D credit, which is a really good thing.

That’s for all innovation?

That’s for all innovation that’s eligible. So, I get money back for that and we are very grateful for that. So, it’s 43.5 cents on the dollar. So, if I don’t have revenue, it’s actually a cash back and otherwise I can offset it against tax I would have to pay. But we have not yet been successful with the larger granting agencies, Arena, CEFC, etc. But we are in constant dialogue, and we are hopeful that we will get onto that journey with the federal and state governments.

And this year, Gelion has accelerated its investment in lithium-sulphur battery technology. Why have you done that? And what’s the difference between that and the zinc–bromine?

So, when we listed in November 2021 in the UK, we came to the market with two technologies. One, the zinc-based technology, the other lithium-sulphur. There was an opportunity from a company called Johnson Matthey that is one of the big companies in the world. They make a third of the world’s car catalyst, for example, and lots of catalysts for the petrochemical industry. So, a many billion-dollar-worth company. They had started to go into batteries and then made a decision not to and they just sold everything they had. Because I’m well connected also in the UK, as a scientist, whatever, I knew about this event that was going to happen and that was a very low hanging fruit. About £120 million worth of development and we bought it for £4.5 million. That really catapulted us to the front end of the world’s development in lithium-sulphur. And the reason we did it was we wanted to complement the IP we had already developed, the intellectual property we had already developed, within our company, and we did that, or I did that because I knew that they had a hole in their efforts that couldn’t do something, and we could. So, putting these two things together was a really synergistic thing to do.

Why would you care about lithium-sulphur? That comes back to what I said before. We want a safe battery with lithium that’s light. We want it safe. We want it very high energy density and we want it cheap as chips. Sulphur is the fifth most abundant element in the world, so it is cheap as chips. It’s a huge waste product from the petrochemical industry so you can get it for close to nothing at a very high quality. And the energy density of those lithium-sulphur batteries is, compared to the BYD batteries right now, something like a factor of three higher. And compared to your iPhone, a factor of two, two and a half higher. So, a third the weight for the same amount of energy, right. That’s big because also it allows for cars, for braking systems to be less robust, which means they’re cheaper. And if it’s cheaper, it means the margin is a bit bigger. The margin in mass produced cars is so small that if you can have lighter batteries, actually the margins go up quite a bit. Overall, electric vehicles can come down in price and help the adoption of that technology.

And will those batteries still be made in western Sydney?

So those batteries are a global play, and they’ll be certainly made in Australia. That’s our hope, our aim. But it will go up in factories that currently are making lithium-ion batteries like the ones in your iPhone. So, they’ll be a retrofit because the technology is so very similar. It’s thin coatings on various films.

We saw with Elon Musk and South Australia, the role that a battery could play in firming up a grid. Is that the future or is it more of the distributed smaller batteries that are household or business level?

I think it’s sort of everything. We need to firm up the grid. And if you look at the projections of battery use, overall, it’s viewed to be about 20% of battery use will go into that stationary energy storage, and that will be enough to do the job. But just to give you an idea, 80% is going to go into mobility, whether it’s aviation or cars. Mostly at this stage of use, cars. So that’s a decarbonisation on the road, as it were.

You mentioned, you know, the use of batteries in electric vehicles. Right now, manufacturers…Toyota, Mercedes-Benz, I think in the last week or two have been saying that they need to reassess the pace of the rollout of electric vehicles because other consumers are wary, or the price is too high. Do you think that electric vehicles are still going to be the way to go, or are we at a period of kind of, maybe, considering alternatives like hydrogen?

I think the issue is the charging infrastructure around. I think what happens is that the car makers are saying, I don’t want to be stuck with all of these electric vehicles because my customers can’t charge them. There will be a backlash once you have these lines or queues to go onto the battery charger. You know, you’re not in a happy space. But there comes a new battery technology that is called solid state. When I talked before about the chemicals going inside the battery backwards and forwards, that happens in the liquid. So, your iPhone battery actually has a liquid in it. Solid state doesn’t. Hence the name. And it is much more resistant to most damage by high voltage. Now, why is that important? Who cares? Voltage is the power an electron has. So, the charge of an electron is one electron. But then if it is really powerful, it has a high voltage. It has a huge capacity to do work. If I put electrons into my battery, which has a high voltage, they can go in there really rapidly. So, a high voltage charging station can charge your battery in five minutes, ten minutes. Can go up to 80% in 10 minutes or 5. So, it is really an exciting technology that’s coming online slowly but persistently. And once that is there, then this whole issue about, well my car is a problem? No – because it’ll be 2 minutes or 5 minutes at the electrical charging station.

What about the hazard? The danger of the solid-state battery exploding, for example?

Yes, so that’s the beaut thing. Those hazards will become less and less with the new battery chemistries. So, we have this nickel manganese, cobalt oxide, which is not good at all. And then there’s still manufacturing issues potentially with the iron phosphate, but that’s a lot safer already. But then the sulphur is extremely safe. Extremely safe. It’d be very difficult. The issue there is for it to keep working rather than for it to explode. It just deactivates.

Is Australia pulling its weight here? Can we do more on climate mitigation, do you think?

Well, we did have climate mitigation dark years I think – as a euphemism for something else I’d really like to say. But the new government we have now is helpfully interested in fact-based policies, fact-based strategies. That is not to say that…the state government under Matt Kean did fantastic jobs, you know, across the spectrum in terms of renewables. But federally we had some trouble. So that’s changed. I think there’s a real appetite, given the Treasury statement and a realisation, given the facts that are starting to be understood, that strategy and policy has to respond to reality, not some wishful thinking. So, I think Australia will be seen to pull more and more of its weight. Certainly, we’ve got the capability here, we’ve got the entrepreneurial spirit, we’ve got the technology capability, we’ve got the scientific academic capability. But matching that to commercial market reality is where the government has to step in and help.

Do you think Australia can be a renewable energy superpower?

Absolutely. We’ve got the land, we’ve got the solar, we’ve got the wind. We’ve got the resources to make all the solar cells, to make all the batteries. We’ve got that in the ground. We have extremely sophisticated mining capabilities already. And yeah, we’ve got some of the best people in the world. The battery market, although you think it’s small, it’s actually a large segment of the overall world market because we are pulling our weight in Australia. It’s often not realised, but it’s the market where loads of battery companies are coming to trial out their products because we are such early adopters. So, the Aussie public is absolutely pulling its weight.

Please join me in a round of applause for Thomas. Thank you very much.

Thank you.

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This is a significant new project for the museum and the records of these conversations will form a new climate change archive preserved for future generations in the Powerhouse collection of over 500,000 objects that tell the stories of our time. It is particularly important to First Nations peoples to preserve conversations like this, building on the oral histories and traditions of passing down our knowledges, sciences and innovations which we know allowed our Countries to thrive for tens of thousands of years.