Sylvia Tulloch of Dyesol discusses Dye Sensitised Solar Cells

Beyond Zero’s Scott Bilby and Matthew Wright talk to Sylvia Tulloch, Materials expert and Managing Director of Dyesol. Dyesol is an Australian company based at Queanbeyan Dyesol has created dye photo electrical chemicals and is leading commercialisation of Dye Solar Cell (DSC) technology.

Sylvia Tulloch podcast

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Scott Bilby: This morning on Beyond Zero, we'll be talking to with Sylvia Tulloch, Managing Director of Dyesol Industries, an Australian renewable energy company that supplies equipment, materials and components for what are called dye solar cells. Dye solar cells turn sunlight into electricity by imitating the way plants convert sunlight into energy.

Sylvia is a materials scientist with over 25 years of experience in establishment and management of high technology business and is co-author of several of Dyesol's patents. Hello Sylvia, thank you for joining us in the studio.

Sylvia Tulloch: It's a pleasure joining you Matthew...sorry... thank you Scott

(Laughter)

Matthew Wright: Now I'll point out too that you are on the line too.

Scott: On the line sorry, not joining us live in the studio.

Sylvia: Ok

Scott: Sylvia now, can you tell us a little bit how you got interested in renewable energy; a little bit about your past and how you got involved with Dyesol?

Sylvia: Sure, it all started quite a long time ago. I'm a materials scientist and the science of converting light into electricity of course is absolutely fascinating and the chemistry involved in doing that, and the materials science involved, was always fascinating to me.

But I started my career in a different area of science and that was what was called 'piezo electrics' (http://en.wikipedia.org/wiki/Piezoelectricity), where you convert pressure into electrical pulses – things like sonar. But the allied.

But my business in solar started in 1994, when the Australian government realised that there was a new invention, a third generation of solar technology which mimicked photosynthesis as you said, had been invented in Switzerland and they wanted to set up a joint Swiss–Australian program to take that concept through to a real technology, ultimately a product. And I was part of a team that was appointed to bring that technology to Australia and start that development program.

Matthew: So, who initiated that sorry?

Sylvia: It was the Australian Government. A group within the Australian government called at the time, the Energy Research and Development Organisation. Sadly, it exists no longer. So we did that and formed a team in Australia, and that team, with people coming and going of course as teams do, continued on with the work until we decided it was ready for commercialisation in 2004. And at that time we then formed a company, a new entity, called it Dyesol. Now, when you consider it's Dye Solar Cell Technology is what it's called, the name Dyesol seems really obvious but I have to tell you we really racked our brains to come up with the name of the company.

(Laughter.)

And we got angel investors who put some money into it and then we floated the company in August 2005. And through that raising of angel funds and then the floating process, and the subsequent access to capital markets, we've been able to raise about $30 million to get us very close to commercialisation.

Matthew: So it's kind of amazing that most Australians probably haven't hear of Dyesol and you're probably one of our more successful, standing on your own feet sort of, commercial solar companies.

Sylvia: Look, I guess there's two reasons that I think. One is that of course we've been working on third generation solar technology and as yet there are no third generation solar panels of any kind, available anywhere in the world. So the solar panels that you see on roofs or in solar farms, etc. are essentially first generation ones. Ones that have been based on the technology that was first demonstrated in the Bell Labs in 1953. So, they've been around for a long time. So there's nothing to see yet I suppose, that's one reason.

The other reason is that we were a born global company. We knew that the majority of our customers were going to be international because what we do is not supply the solar panels. What we supply are the materials and the technology that others need to manufacture the solar panels. And the reason that we did that was I guess, two-fold.

One is, it takes an enormous amount of money to set up a manufacturing facility to make solar panels because they need to be in very large volumes; because the economics don't work if you've got very small volumes. And so that was a huge ask to raise the probably hundreds of millions that people need to manufacture, to set up a solar panel factory.

And that other one was that, I guess, we were thinking, 'how can we get this technology out as widely spread as possible?' because we started this program in '94, '95. Now, we didn't know about climate change then; certainly I didn't. And so it was fascinating science, we thought it has a commercial future, but then in 1998 I went to a conference and the CSIRO gave a paper and in that paper was that graph that Al Gore had made so famous; the climate change graph. And I can remember that moment, looking at that graph and saying, 'My God, not only are what we're doing really interesting science, this is really important!' And so that, being able to get it out as widely as possible, and as soon possible, is part of the driver. So, by supplying the materials and letting, encouraging other people and working with them to set up the factories to make the panels, that's how that happens. And so what it turned out was, that the people that we found who were interested in doing that are mostly international. So, 95% of our sales are overseas. So, we don't have a big brand, marketing campaign in Australia because there's no need for it. Within the solar industry, internationally, globally, we're certainly recognised.

Scott: Now the time is 8:38am. You're listening to Beyond Zero and we're interviewing Sylvia Tulloch, Managing Director of Dyesol Industries. And Sylvia, can you just describe to the audience how Dyesol's system works?

Sylvia: Sure well, as you say it mimics photosynthesis. In a leaf the dye is chlorophyll, a green dye, and chlorophyll is green because it absorbs all of the red part of the light spectrum and reflects the blue and the yellow. So, what you know about a dye is, and as long as you can see a colour, that it is absorbing in the part of the spectrum the energy that you're not seeing. And so that's the basic principle. So, normally you would have a molecule of dye and it would absorb part of the spectrum and it would wobble because it's energised and its electrons would free up, but in normal conditions it would then go back to a rest position. But if you have a nano-particle of titanium dioxide, or similar material, next to that molecule of dye then those freed up electrons will 'hop' on to the nano particle and then they will 'hop' on to the next nano particle and it's about a million 'hops' until they get to a conductor that takes the electricity out.

So, that's the basic principle of the dye solar cell which is different to a first or second generation cell. The way they work is, you have an atom of silicon or similar materials and you have a photon of light, and the photon of light hits the atom and if that photon is energetic enough, it knocks off the electron and that electron conducts. It is quite a different process and therefore has different characteristics.

Matthew: So, you talked about the kinetic factor and the million 'hops'. How far does it actually travel to go a million 'hops'? Like in millimetres or...

Sylvia:The million 'hops' is around a centimetre. So, if you remember here we're talking about a nano-scale so it's a very small scale.

Matthew: So, it's a pretty amazing sort of work?

Sylvia: Yes.

Scott: So ,do you turn these cells into tiles or panels... Feel free to interrupt at any time. You know a lot more about this than me and you'll be a lot more interesting I assume.

(Laughter).

If you can talk about those a little bit and tell us some examples of where they've been implemented or how they can be implemented?

Sylvia: Sure. Now this is a multi-layer structure so the layers are, a layer of nano particles of Titania; now Titania by the way is the white stuff in white paint, the white stuff in toothpaste, so it's a very plentiful, benign material but we're using nano particles, so smaller particles of it. You have a layer of those nano particles, then you have the dye infiltrating onto the nano-particles, then you have a layer of electrolyte, and then you have a layer of catalyst ,and then you have to have conductors, top and bottom.

Now, that's all laid down on substrate underneath and a superstrate on the top – one of which must be transparent. So you could put it on glass, for example and it would make a glass sandwich and then it can be like a... I was going to say like a window, bit it's not a window in the case of being totally transparent. You can see through it but it's coloured because of the dye. Sort of like a modern stained glass window effect, so mostly we see those glass panels being used in buildings but in facades where you don't have to have window views. So it can be glass.

We're working in a company in the UK. The company's called “Corus” but most people know it by it's old name which was British Steel. They make a product that we have in Australia called Colorbond (http://www.colorbond.com/), they called something – they call it 'Colorcoat' actually, in the UK. And they are, with our help, laying down these layers on the steel roofing with the objective of having Colorbond material that's actually got these layers on and wires coming out the end and is a Colorbond roof but is also a solar generator. So it could be on steel.

We have a project that we did actually for the Australian Department of Defence, where the aim was something very light-weight and rugged and in that case, it's on a titanium foil. And that's a product that was designed for the army so that they can carry it and recharge their batteries because batteries are a big problem for the army – in fact they're a big problem for the world actually – batteries. Did you know that 5 billion batteries are thrown away every year in the United States?

Scott: Wow.

Matthew: Shocking.

Sylvia: So having rechargeable batteries and having a system like a lightweight solar panel that can recharge batteries is a huge advantage in lots of ways. We've developed that for the army although we'll be taking that further for commercial users as well.

So, there's various things that you can have. We often call it a tile, a glass tile, because it always looked like to me more like a bathroom tile than a roof tile. So, we don't see it as being tiles as in the ceramic tiles on roofs but rather the roof could be something like Colorbond and the glass or the walls would be something like these tiles, made into panels.

Scott: OK, and that military application sounds interesting. So, does that mean that you can build those cells into flexible structures?

Sylvia: Yes, we have done that. So we've demonstrated and delivered to the military some prototypes of that. And the aim for that is then to go to pilot plant in the next stage there. And of course once you've got something that the military can make use of that, so can campers and caravaners and people with remote requirements for electricity, like pumps etc., so that's a really interesting project also.

Scott:So, they must not only be flexible, but also robust then?

Sylvia: Oh yeah absolutely. I mean that's a good thing with working with the military. A is, you know in America almost all high tech industry is funded by military contracts. But in Australia it's very rare. So, we've been both pleased and privileged to actually have one of these contracts. So, they're a great customer because they pay for the development and they let you use it for all non-military applications for free – freely – they want you to. And also their feedback is great and information about how robust and how they want it tested to show how robust it is and how they want it tested at the bottom of 3 metres of water and threw it off a 2-storey building and all those things.

Scott: Wow.

Matthew: You obviously have patent and the intellectual property to do with the dye solar cell chemicals.

Sylvia: Yes, we've got a range of 20 patents covering various aspects. And we also, remember that we worked in the joint Swiss-Australia program, so the original concept was developed by a Swiss scientist whose now actually continues to work with us. He's Chairman of our technology advisory board. His name is Michael Gratzel (http://en.wikipedia.org/wiki/Dye-sensitized_solar_cell). We hope one day, he'll get a much deserved Nobel Prize for it.

Scott: So he invented the dye-sensitised cell?

Sylvia: The idea of the artificial photosynthesis, yes. So, it's a bit of an unusual situation in Australia where here we are leading the commercialisation but the original concept was in Switzerland.

Matthew: What sort of conversion efficiency do you get across the application surface area? Like you know, if you actually roll out a whole series of panels?

Sylvia: Well in the lab, the peak efficiency that's been demonstrated for DSC single layer is 11.4%. We think that second generation amorphous silicon cells are about 7% and we think that's what dye solar cells will be rolled out at. At around that percentage. And then of course, over time as there's increasing work on them, dye efficiencies and the nano particles, etc., that will go up and we anticipate that by 2015 it will be about 15%.

Matthew: So, 15% in the lab?

Sylvia: Ah huh [yes].

Matthew: OK, that's pretty impressive. Are there any known upper limits of where you'll get to, like is that sort of 20% ceiling or...?

Sylvia: No, there isn't because – well up to 100% of course. It's a matter of capturing that light, so there is no limit. See, there is a limit in first and second generation because you have photons of light. It takes a certain amount of energy to knock off an electron. If you have less than that, it doesn't work, and if you have more than that, it's wasted. And, so you can actually do a graph of the energy of all those photons that are coming down from the sun and we know that there's only about 30% of that energy can be taken up by a Silicon solar cell, first and second generation.

But it's not like that with a dye solar cell because the dye is absorbing the spectrum, so provided you can actually get the dye's lined up and a single dye won't do it, but there are various things about mixing dyes and having levels of dyes, so that theoretically you can then capture the whole part of the spectrum.

Matthew: Now, I'm no expert on photosynthesis or photoelectric conversion but what I was wondering was – we had Mark Wanlass from the National Renewable Energy Laboratories and he does multi-junction conventional photovoltaics. So, he puts three layers together and I was wondering if there's any way of adding the dye solar layer as well to increase the conversion efficiency or would it not work?

Sylvia: Well, we've done two layer, dye solar cells. That's one of the ways of having multi layers of dyes. So, what you would do there for example is have one red dye, and that's absorbing the yellow and blue part of spectrum, and underneath that you have a green dye that's absorbing all the red part of the spectrum. And then theoretically, you would then, we haven't done this yet, but you could also... there are dyes that absorb in the infra-red and... so that you'd have another dye thats absorbing the infra-red. So, that stacking system is how you can move closer towards 100% theoretically; although you're not going to get there, (ie: you can only get to 100% in theory).

Scott: You're listening to Beyond Zero and we're speaking to Sylvia Tulloch, Managing Director of Dyesol Industries, an Australian renewable energy company and obviously we're on 3CR. Sylvia, I don't know if this is a silly question but can the technology be used indoors as well as outdoors?

Sylvia: Yes, I mean that's another advantage of dye solar cell technology as opposed to first and second generation because indoors we don't have such energetic light and so the earlier generations don't work. Whereas as long as you can see that something has colour, we know that energy is being absorbed. So that opens up... I mean at the moment, the only real indoor application for solar technologies is calculators and that's because they use such little power. But we have among our customers some of the world's largest electrical, electronic equipment companies, people like Sharp and Sony and Samsung. And they have DSC development programs, clearly so that they can integrate local generation into electronic equipment, and that need to be indoors of course.

Scott: And I read that you guys built a facility in October 2008 I think it was, in Queanbeyan, just outside Canberra? Can you tell us a little bit about that?

Sylvia: Sure. We've been in Queanbeyan since even before Dyesol was born; the team was sort of centred here and we have a pilot plant. So, we've made panels and we've actually installed them in a couple of buildings to learn what happens and how to do it and all. So, there are a couple of photographs around with those buildings with dye solar cells installed in them. But they basically, I always say hand-made by scientists, so not a commercial proposition, but still we can make solar panels – dyes solar panels – and we do and we use it to test our material. So, we've been doing that here for quite some time.

What we needed to do last year was scale up our ability to supply the materials because our customers are moving up the chain. So, if you're doing real research you need small quantities of materials, but as you move up towards development rather than research, and then you move from development to demonstration and pilot plant etc, you need more and more. And so we've had to scale up and so we've set up a new – we've leased a new factory area where we can manufacture our materials at much larger scale, and that of course drives down the price of them which also needs to happen to make the whole thing commercially viable.

Matthew: So, these are your chemicals and things like that – not the actual finished product?

Sylvia: No, so we've got the pilot plant and we make the panels there and for example, we've done a couple of demonstration buildings and we've supplied products to the Department of Defence to test but this factory I'm talking about now is to make the dyes, the electrolytes, the nano particle paste, the catalyst, that are the various layers of the dye solar cells.

Scott: Now, I was looking at your website and you sell quite a range of dyes and quite a range of pastes and etc., etc. Can you tell us, with the dyes in particular, you sell about half a dozen. Can you, just for the audience, explain why you sell so many different ones?

Sylvia: Ok, so the dye range that we sell at the moment, and over time that will get even broader, there's various things you might want out of them. But the basic one I suppose, is that you might want a different colour. So, there is a choice between at the moment, a reddy-brown dye and a black dye that works in a dye solar cell. And we've got others in the pipeline like green, brown, etc., but their yields are not good enough, their efficiencies are not good enough yet, but they'll get there. But at the moment colour. So you may want – in that range, there's one black dye, that will give you a sort of blacky-grey looking panel. And if you're integrating it into a building or a piece of electronic equipment colour matters and the other one's a reddy-brown.

Then there's one that is a bit more expensive but is more stable. So if you are looking for, you know, multi decades of lifetime then you need a very, most stable dye that you can – that's going to maintain its efficiency for a very long time. But if you're looking to incorporate it into a charger for a mobile phone, you're probably only looking for 4 or 5 years so you would choose one that was cheaper – if you could get a cheaper one that wasn't as stable because you didn't need the stability. So, there's all those kinds of equations and they're all built into our dye range.

Matthew: That's fantastic. And I noticed that you have a joint research venture with Queensland University of Technology and I'm wondering if you have anything going with the ANU as well, given that you're located a stone's throw from the Australian National University?

Sylvia: We worked with ANU – their chemistry school. It's great to have those facilities available and we've used them as a ... they provide a great service to use when we need to do some testing when we don't have the equipment to do the testing. But the solar school at ANU is very much first generation so... and it's physics, it's not a chemistry-based solar cell group. So, we don't work with the solar cell group really.

Whereas QUT, we've been working there with them for a long time and they've got a team there that's across all our issues, nano particles and also in particular the research linkages grant (http://www.research.qut.edu.au/development/find/external/arc/examples/linkage.jsp) that they have, that we're their partner. This is on the cathodic system. These solar cells are in many ways like a battery in how they work, so they have a cathode and an anode and most of the work around the world has been done on the anode part of the system, which is the nano particles and the dye on it. But there's also the cathode part of the system and so QUT are working on what can be done to improve efficiency by improving the cathode.

Scott: Now, I also read on your website that the 3rd International Conference on the Industrialisation of Dye Sensitised [Solar] Cells is coming up in Japan. Can you tell us a little bit about that conference and what outcomes Dyesol are hoping for?

Sylvia: Sure. About four years ago, we realised that all of the conferences around the world on dye solar cell technology were very academic and that's fine. They have a place and have to keep going. But we felt it was important to get together people who were moving down the industrialisation path to have an occasion where we could get together and exchange information. So, we set up, the first one was here in Canberra, just three and a bit years ago. We then did the second one, about 18 months ago in Switzerland, in St Gallen. And this one is coming up now, in Nara in Japan.

So, about 200 people will come. About half of them will be from companies and about half from... actually to be really accurate ... with the one in Switzerland, 48% were from companies, 48% were from universities and 4% were from investor groups – fund managers or analysts or whatever, and a couple of journalists. So that's the aim, really.

Of course there's competition to some extent within companies, and academics, working in any field. But when you've got a market that's growing as fast as the solar market is we think, and I think our colleagues all agree with us, that there's more to be gained by sharing than by keeping things too secret. So, of course there's always some things that are kept a little bit secret but this is a great opportunity to see how everybody else is going, how close they are to commercialisation, where the challenges are, what's no longer a challenge and has been done, what demonstrations been done, what progress they've had in terms of marketing their technology and yeah, there's been two great programs in the past and we're really looking forward to this one in Japan. And we facilitate that as sort of a service, part of our duties to commercialise the technology. So we organise it.

Scott: Ok, well it sounds like it's going to be a fantastic conference and it's good to hear that there's quite a high percentage of investors there and Sylvia, I would like to thank you for explaining dye solar cells to us and it's good to hear that... well, you hear of so many inventions and technologies developed in Australia that disappear overseas and it's good to know that something was developed overseas in collaboration with Australia. It actually seems to be...

Matthew:...here!

Scott: Yes, it's here! It's so exciting.

Matthew: You're bucking the trend!

Scott: Thank you very much Sylvia.

Matthew: We hope to get you back soon.

Sylvia: That would be a pleasure. Good talking to you.

http://www.dyesol.com

Transcript by Miwa Tominaga