Jose Zabata of ANU's solar themal group talks SolarPACES

Beyond Zero's Matthew Wright speaks to Jose Zabata, electrical engineer and member of the ANU's solar thermal group, about Solar PACES, the International Energy Agency's "Power and Chemical Energy Systems" (PACES), Solar Thermal Technology and associated international conferences.

Further reading:

http://www.solarpaces.org/

Beyond_Zero speaks to Jose Zabata ANU solar thermal group

download

Transcript

Matthew Wright:      Today on Beyond Zero we’re speaking with Jose Zapata and he’s a member of SolarPACES. Well, he’s a member of the ANU’s http://solar-thermal.anu.edu.au/ Solar Thermal Group. And along with CSIRO, ANU represents Australia on  http://www.solarpaces.org/ SolarPACES which is the International Energy Agency’s Solar Power and Chemical Energy Systems sub-group, and they’ve been active for over 30 years.  

So we’ve got Jose on the line from Canberra. Thanks for joining us, Jose.

Jose Zapata:      Thank you for inviting me, Matt.  

Matthew Wright:      It’s great to be speaking to some of our experts in solar power research and development. Obviously there’s a bit of a hub of that at the ANU, Australia’s leading research university. Can you tell me a bit about how you got involved in renewable energy, Jose.  

Jose Zapata:      Well, I would like to say first that I’m not yet an expert because I'm only a PhD student at the ANU Solar Thermal Group. I’m an electrical engineer and I’ve been working as an engineer for a few years. I decided that I needed a change and that I wanted to work for renewable energy so that’s why I joined the ANU Solar Thermal Group, so I could get involved in renewable energy research.   

Matthew Wright:      And in fact you came over from Chile to do that.  

Jose Zapata:      That’s right. But that’s not really directly associated with me joining it. In Chile there’s enormous interest in renewable energy. As you know, many countries in the world are facing energy crises and Chile is certainly one of them. I’ve always been very interested in renewable energy. There’s enormous potential in my country for wind and geothermal and of course solar-thermal.  

But my life circumstances found me in Australia and then I realised that there was a very good group that I could join. And I was lucky enough to be accepted.  

Matthew Wright:      So there’s some great work then. Of course that's ANU’s Big Dish research which centres around that technology.  

Jose Zapata:      That’s right. The ANU has pioneered the concentrating dish technology in the world, especially focusing on big dishes. So they’ve just completed the biggest parabolic concentrating dish in the world. It’s the only one of its type.  

And it’s recently started doing some experimental runs with a steam carriage receiver which basically is just a solar-thermal energy name for a boiler. So you flow water through the focal point of this concentrator and out the other end, if there’s enough sun, steam comes out. That’s basically the focus of my research, how to use the ANU dish to generate steam to use directly in turbines.  

Matthew Wright:      So that’s for what they call 'on sun' applications? So you’re not talking about storage there, you’re just talking about being able to generate in real time when the sun’s out?  

Jose Zapata:      That’s correct. Because in solar thermal energy what’s at the moment proven technology is what the Sandia Labs in the United States started about 30 years ago and just generating steam directly from the sun has been a tested and proven application. There’s still many plants that operate only on sun.

The concept of thermal chemical storage is still in development. So if you need to go and find a plant that generates electricity with sun, most of them will be direct steam generation.  

There has been work at the ANU Solar Thermal Group on steam generation for some time but it’s actually caught a new breath. It was very good timing for me because I was interested in it and there’s, you know, renewed interest because it’s an application that can be put to work really fast. And when dispatchable power is needed and storage is not an impending need, you can readily and with available technology just generate steam from the sun.  

Matthew Wright:      Now the SolarPACES that we’re talking about, there’s a conference, I understand, and it’s happening in Perpignan in France from the 21st to the 24th of September 2010. Now speaking to you it's obviously worthwhile because you attended the previous SolarPACES conference that was in Berlin.  

Jose Zapata:      That’s right. When I joined the Solar Thermal Group as a PhD student I was encouraged to go to this conference to get a feel for what is the current state of the art in solar thermal technology and what the rest of the world is doing. And that was a very good experience because SolarPACES is a consortium of nations that have decided to take on the task of developing concentrating solar power and chemical processes with solar energy. And the SolarPACES conference is their annual meet.  

It’s mostly scientific because most of the groups involved in the various countries are from a scientific research background. So there will be the ANU group and CSIRO in Australia and the equivalent bodies of research in countries such as France, Germany, Spain, the United States and many others. So the tone of the conference has always been a meet-and-greet for the few people in the world so far that study this type of technology and exchange information like a scientific conference on what’s the current state of work, what’s the latest research. And, of course, if there’s any business involved, that’s also attached to it.  

What I didn’t know is that until last year that was pretty much the tone of the conference but since last year there’s been a great increase in the interest of industry in getting involved. And there were many industrial partners associated with this research, organisations in Europe. There were private companies offering services, offering engineering and consultancy services and ancillary equipment. They were very keen to meet you and get their foot in the door first so that you use their technology first in your research. Because many of them are now in Europe sprouting into commercialised technologies so there’s a big interest now in industry.  

Last year all I did was just to attend the sessions and it’s actually quite intense because you spend pretty much all day listening to other people’s presentations on various topics. There are so many aspects of this research and there are still many competing technologies or there’s a diversity of technologies being studied.  

So I was all day listening to very good scientific research and everything was going above my head. I was thinking, well, it’s my first year, I don’t know what’s going on. But it was very interesting and I met a lot of interesting people too. I’m mostly interested in simulation and control plants so I had the luck of meeting some of the people in the field that do that.  

After the sessions there’s all these posters outside where you can go and meet the people that did the work and you can exchange ideas. I was basically introducing myself saying, ‘I’ve just joined the Solar Thermal Group. I’m starting to study. What are you working on?’ Sometimes you go and have lunch with them. It’s great.  

Matthew Wright:      An interesting thing, I think they said that they were way oversubscribed at that conference in Berlin. In fact they'd usually had a hundred to two hundred people and they were up to six, seven hundred people. So there’s just been a boom in solar thermal industrial scale-up and interest.  

Jose Zapata:      That’s right. And that’s only something that I found out once I’d got there. Last year because it was my first year I spent most of the time studying and getting to know the technology. And I went into the conference and I remember comments from other people in my group that had been there before, ‘Oh, it’s just a very small conference. You always meet the same people.’ And I walk into this conference hall in a hotel in Berlin and there were hundreds of people there and there were big stalls with big companies trying to promote their products and presentations and little scale models of proposed plans.  

 And because it was my first one, I couldn’t tell the difference but many people that were there before were like, ‘Oh, this is a very big change, a very big conference.’ If you go to this year’s conference web page you can see that there’s a lot of partners and associated sponsors that are actually commercial partners. So I think there’s been some kind of boom in the last year or two. And it looks like it’s going to sustain in the future and this conference is going to grow.  

 There’s other technologies in solar energy such as photovoltaic that you go to conferences that are almost of 30,000 people. They’re huge and they have a whole exhibition centre for commercial partners and another one for science and a scientific conference. I would never say that at this stage solar thermal is going to go as big as that but there’s certainly a springing in the amount of activity that solar thermal energy is generating in the world.  

Matthew Wright:      Now for listeners that website to find out about the Perpignan conference is http://www.solarpaces2010.org/  

Now just tell us about what SolarPACES stands for and what the coverage is of the conference?  

Jose Zapata:      I think from memory SolarPACES means Solar Power and Chemical Energy Systems. So basically the focus of this group is on the research of power generation and chemical processes using solar energy, because both in power and chemical energy processes, the generation of heat is directly linked to fuel and therefore it's one of the costly aspects of any chemical process or power generation.  

So if you can take the fuel from the equation and actually use solar energy, then, you beauty, you suddenly have a much cheaper chemical process or much cheaper power. So that’s on the good side.  

On the bad side you know that the sun rises every morning and sets at night and many chemical processes need to run 24 hours a day. So basically the focus of research is figuring out whether it’s possible to perform all these processes with solar energy and second, how do you adapt the process to the variable nature of the sun? That’s it in a nutshell.  

So anything that needs great amounts of heat can be applied to solar thermal energy. And I guess that the look into the future, now that power generation with solar thermal energy has reached a stage where it’s no longer a question of whether the technology works or not but a question of whether the cost of producing it reduces when the technology becomes cheaper, the outlook to the future, I think, is to generate new types of bio-renewable fuels and maybe replace some costly chemical processes with a solar alternative so that you don’t get any emissions from them, et cetera.  

Matthew Wright:      We’re talking with Jose Zapata. He’s from the Australian National University's High Temperature Solar Thermal Group. And along with CSIRO they’re the Australian delegated representative organisation of the SolarPACES International Energy Agency's sub-group.  

Now we’re talking about the Chemical Energy Systems part of SolarPACES. Most of that does seem to be concentrated around storage technologies but the other main area is fuels, so creating liquid fuels, you mentioned that. Are there any other sorts of chemical reactions that are covered by the SolarPACES umbrella?  

Jose Zapata:      I think if you go to the SolarPACES sub-group website there’s a whole list of activities that they undertake. I haven’t gone through it in detail because it’s not really the current focus of my research. But I’ve browsed through it and there’s a whole host of other processes that are listed as in a 'to do' list. Like, we need to look at this and we need to look at that. And I’m sure that besides chemical storage and biofuels there must be others.  

At some point you might want to think whether you want to produce plastic with solar energy because it’s better than producing it with coal-fired furnaces. But unfortunately I’m not really aware of all the variety of things that can be studied. It’s just that when you go to the conference you see what is being studied at the moment and that’s because it’s the greatest concern for both the scientific groups and the community at large, which is to find a way to replace fossil fuels.  

Matthew Wright:      I did notice that two of the things mentioned are water purification and desalination. They were two areas that obviously don’t get anywhere near as much research focus as solar thermal direct heat generation, receiver design, collector design, storage and things like that. But water purification is an interesting one.  

Jose Zapata:      Yes, that’s correct. There are many applications for solar energy and water purification. There was a demonstration in Spain that you can greatly reduce the amount of particles in water by just exposing it to ultraviolet light. But that research was more focused on treating sewage water to turn it into irrigation water so that it was safe to use in irrigation but not back to drinking water.  

But certainly water purification and desalination are two areas that are of great concern to SolarPACES. I mean, obviously they’re chemical processes and therefore if you can replace the fuel which can perform those, of course, then they’re the focus of the conference. I guess you’re right but unfortunately I haven’t looked into that area.  

Matthew Wright:      At the last conference it was interesting that, talking about storage again, solar thermal’s positioning, it’s market opportunity, does seem to be with dispatchability. The attendees were really surprised that over the previous 18 months the cost of photovoltaic – that’s the direct panels that people have on their domestic rooftops that turn photons, that’s the sun’s light, directly into electricity – they were surprised at how fast that had come down in price.  

And then the real differentiating factor was the dispatchability. Can you tell us a bit about how dispatchability is so important and a higher value power in modern electricity grids?  

Jose Zapata:      Well, modern electricity grids around the world all share the same downfall that they cannot store any energy. So whether you have a coal-fired power plant, nuclear power plant or wind, the energy that is injected into the grid line will travel through the line and go directly into where it’s used and otherwise will not be used. There’s not like a way to generate it and put it in a silo like you could with wheat and flour and so on.  

So when they talk about dispatchability, it’s the ability of a particular power plant to inject power into the grid at a particular time. In countries like Spain, where the best of the discussion was from, they had a variable demand because it’s related to their economic activity. So their peak was at 8pm in the evening when both all the commercial stores are still open and people are carrying on with their lives at home. And there’s an increased amount of activity related to that. The minimum was at 2am in the morning when basically everyone is asleep so there is very little energy use for the economic and normal activities of Spain.  

So in that case you would think that you have all these plants producing normally and then suddenly at 6pm, at 6.30pm, everyone starts cooking dinner and you turn on all the lights because all their trade needs to continue going into the hours of the night. But they need illumination for their stores and inside their stores. So there’s a surge in demand and you need to be ready to just crank up a new machine to start injecting power.  

So that’s the concept of dispatchability, the ability to turn on a machine to inject electrical power into the grid when it’s needed and immediately.  

Therefore, when they talk about solar thermal power with storage, they are talking about the fact that you can have all your mirrors and arrays concentrating solar light and warming up this molten salt and basically charging it like a battery. And having it ready to hear the phone call from the dispatch organisation saying, ‘We need power now.’ And then basically they just turn on their turbine and they start generating power, almost matching exactly the amount of the surge in demand that occurs in those places.  

Dispatchability in other parts of the world that might have their grid more dominated by industrial activity, such as Australia, you will see a very big baseline happening all the time and then small peaks and small sags that are related to the normal activity of people. Dispatchability in this context means that you have to have power whenever we want it which basically means all the time.  

So dispatchability as a concept is the ability to inject power into the grid whenever you want to. And how solar power could fulfil it in Europe is because of their thermal storage and how fast they can get it going. It’s only a few minutes that it takes to warm up a turbine if you have a ready, available heat source and get it to inject power.  

Matthew Wright:      So in effect it acts like a hydro dam or a gas peaking plant on a current grid?  

Jose Zapata:      That’s correct. And in fact electricity markets around the world are very regulated because of how tightly they link to the economic activity of a country and the security of a country. Because if all your lights run out then havoc starts wreaking and so on. So there’s in fact economic encouragement for power companies that actually assume the risk by building a power plant to generate in these times that are required to be more important.  

So the regulating body will pay more per kilowatt to the companies that can generate at peak time. That’s where solar thermal dispatchability becomes an economic advantage and makes a plan more feasible because you can inject power to the grid right at the point when you get the most bang for your buck, making your plants and the risk that you assume by building your plant more cost effective and economic.  

Matthew Wright:      In 1978 in Crimea the USSR built a power plant called C3C-5 and that was a direct steam power tower, the first one of its kind. Now straight away after that there was a mini cold war where the French and the Americans built a plant. The Americans doubled the size in 1980 and built a 10 megawatt direct steam plant called Solar One. But over in France just near Perpignan, I think a place called Odeillo, they built the http://en.wikipedia.org/wiki/Themis THEMIS Power Tower   .  

A feature of this year’s SolarPACES conference is a tour of THEMIS, a tower that was built with molten salt back in 1979 or 1980. Can you tell us a bit about the THEMIS Power Tower and the tour?  

Jose Zapata:      Well, I can't really tell you about the THEMIS Power Tower because I’ve actually signed up to go on the tour and see what it’s all about. Perhaps when I come back from my trip I can tell you all about it. But in the program for the conference there’s four days of active sessions where the scientific community does all their presentations and there’s meetings with industry and there’s meet-and-greet time and networking time.  

Then on Saturday morning there’s the option to sign up to this technical tour that last year actually happened in Berlin as well. It’s where the hosts of the conference show you some interesting solar thermal technology. And in this case, quite right as you say, it’s the THEMIS Solar Tower and also the research facilities at Odeillo.  

Odeillo is a town in the south of France, further south than Perpignan in the foothills of the Pyrenees, so it’s as far south as you can get in France because it’s almost on the border with Spain. It’s where you get the most sun; I don’t know about winter, but in summer you get clearer days with better sun, so it’s an ideal place to put your solar thermal plant.  

The research facility has solar furnaces which basically are just a big array of mirrors that can concentrate to a box. And in that box you can put whatever you want and use it as a furnace instead of making a coal furnace, so you can melt things like metals and so on. Also in that area is where that solar tower is.  

I can tell you what solar towers are in general which basically are big concrete towers with a focal point on top where you collect your heat and a lot of mirrors on the ground pointing towards it during the day. And as the sun moves they all keep on pointing to the tower. On the top of the tower you put  the device that you want to collect heat with. It might be a boiler or it might be some molten salt melter. Then you bring that down and you use your heat for your solar thermal energy.  

So I suppose that that one in particular will look nice and old and it won’t be top of the line like the ones that you see being built in Spain. But I’m pretty sure they will do the job as well.  

Matthew Wright:      Those towers, they approximate the shape of a paraboloidal dish, which is what you work on, but don’t do that as effectively as a dish but have an economic advantage in terms of construction and field size.  

Jose Zapata:      That’s right. There’s basically a separation between one-axis tracking technologies and two-axis tracking technologies. One-axis tracking just moves from east to west following the sun and that’s it. So they just get the incidence of the sun moving from east to west. Whereas two-axis tracking, they look at the sun just like a sunflower and they follow it both in east and west and in altitude. So when the sun goes high up, the tracking device is moving up as it’s moving westwards.  

But in the case of our dish, it moves in two axes. It looks pretty much like a steel sunflower tracking the sun all day. In the case of towers, what happens is that you have all these mirrors that are changing shape as if they were a field of sunflowers moving around in two directions. So two-axis technology is more effective than one-axis technology but that’s as far as I could tell you. I’m not really aware of the specifics of the differences between solar towers and dishes. All I know is that our dish can generate a lot of heat.  

Matthew Wright:      Yes, I think the main difference is the dishes are perfectly on the sun and the tower is almost perfectly on the sun. So that’s the main thing. We’re going to have to leave it there. It’s been great speaking to you, Jose.  

Jose Zapata:      Pleasure.  

Matthew Wright:      And, of course, you can find out more about the ANU Solar Thermal Group at http://solar-thermal.anu.edu.au solar-thermal.anu.edu.au   . And exciting things at the ANU Solar Thermal Group working with the big dish which hopefully in the next few years will see commercial power plants in Australia and in developing countries.  

So I guess you’re looking forward to the commercial angle of the industry that you’re getting involved in?  

Jose Zapata:      Every time that you study all these things and you sit at the computer for three years, it’s always exciting to see it happening in real life. That’s one of the kicks that you get as an engineer, that you get to see the machines that you work so hard on move.  

Matthew Wright:      Yes, absolutely. Alright, we’ll have to leave it there. So thanks very much, Jose.  

Jose Zapata:      Thank you.  

Matthew Wright:      We’ve been speaking to Jose Zapata and he’s an expert – well, I’d call him an expert. He’s a PhD researcher at the ANU’s Solar Thermal Group in direct steam generation from paraboloidal dishes. He’s doing receiver design and looking at how you produce steam optimally from those solar thermal devices.    

Transcript by Melody