[ This is the transcript from Australian science TV program, Catalyst. Three different contributors have contributed to the newswire, which is might be a record, so have reprinted here in full. -AF ]
There’s been a lot of talk about a nuclear future for Australia. But we already have an enormous nuclear reactor providing us with massive quantities of energy – the sun. Our reliance on greenhouse gas emitting coal-fired power stations is unsustainable. Solar power is an obvious alternative choice for sun-drenched Australia, so why aren’t we already living in a solar economy? There are a number of promising technologies being developed and the solar future may be about to arrive.
Narration: There’s been a lot of talk lately about a nuclear future for Australia. But we already have an enormous nuclear reactor - pumping out phenomenal quantities of power, The Sun.
Dave Holland: There is sufficient solar energy to power everything that we do. The sun delivers about 17,000 times as much energy every day as what mankind uses. So the energy is there. What we have to do is to drive ways to harness that energy.
Narration: Australians are the second worst carbon emissions culprits per capita in the world. More than half our electricity needs are served by coal fired power stations, and while coal remains cheap and plentiful there’s little political advantage in changing the status quo.
Yet sunlight is also plentiful in Australia we have more of it than anywhere else on earth.
And solar has the right credentials it’s clean, green and infinitely renewable, but until recently harnessing the Sun has been expensive and unreliable. So has anything changed?
Mr Wes Stein: We’ve come a long way and now we’re right at the point of being able to say here it is industry, you can start to take it over right now.
Dr Paul Willis: While they haven’t received a great deal of publicity, Australia’s solar scientists have been quietly achieving behind the scenes. They now have a variety of technologies that will provide clean, cheap and sustainable energy from the sun.
Narration: For over 30 years the Liddell power station has generated electricity in the conventional manner, burning coal to create heat to make steam to drive turbines. Things are about to change dramatically thanks to the installation of a new hybrid solar-thermal power plant. The sun’s heat will preheat the water and thus cut the amount of coal used.
Dr David Mills: The point is that we can supply useful heat at a useful temperature to a major power station, and therefore cut the fossil fuel usage into that station.
Dr Paul Willis: So this is your prototype station.
Dr David Mills: That’s right.
Narration: This is solar-thermal technology, concentrating the sun’s heat to boil water, just like domestic solar hot water systems but on an industrial scale.
Dr Paul Willis: And it performed up to expectations?
Dr David Mills: Surprisingly it did, the first time. We overlap the light from all the long large mirrors on to an inverted absorber standing high on towers, and that contains steam pipes. What we’ve demonstrated here with the first prototype is the ability to get up to the temperatures required for the input of heat to a conventional power station. In this case it is a coal fired power station but it could be an oil-fired power station or from other fuels.
Narration: Construction has commenced on stage two, a significantly larger solar facility.
Dr Paul Willis: So this is the new array?
Dr David Mills: Yes, that’s right. It’s going to be 5 megawatts, which is about 20,000 square metres. So it’s not something you’d put on the back of your house. And this is just a small one.
Narration: When it’s completed, this facility will be capable of providing power for 20,000 homes. That’s roughly a small town.
Dr David Mills: Once we learn how to manufacture these arrays on a very large scale, which is happening right now, we’ll be able to built plants with their own turbines without any fossil fuel.
Narration:In fact planning is already underway for a 100% solar-thermal facility based on this technology, at Moree in the New England region of New South Wales.
Dr Paul Willis: Boy, that’s some dish you’ve got there.
Dr Keith Lovegrove: Yes that’s the world’s biggest paraboloidal dish solar concentrator Paul.
Narration: This is the initiative of the Australian National University. They’ve been working on solar since 1971. They think big dishes are the way to capture the sun’s heat, as opposed to the long, flat mirrors we saw at Liddell.
Dr Keith Lovegrove: We can make steam at the same temperatures and pressures as you’ll find in a coal fired power station. We’re in the middle of taking it into commercial production. And a small power station with an array of about a dozen should appear within the next few years.
Narration: Another form of solar power on the cusp of going mainstream is solar photovoltaics. Unlike solar-thermal technologies, which use the sun’s heat to boil water, solar photovoltaics bypass heat and water and generate electricity directly from sunlight.
Dave Holland: We concentrate the sun 500 times into a very small amount of very specialised high-grade ultra efficient photovoltaics. And we’re building power stations on small grids in central Australia where we are complementing the existing diesel generators.
And it’s our intention to build a 150 megawatt power station in northern Victoria over the next few years.
Narration: And that’s enough to power 75,000 homes, equivalent to a small city.
Dr Paul Willis: There’s always been one sticking point with solar power. What do you do when the sun goes down? Storing solar energy so that you can use it at night or whenever you want to, that’s another set of technologies that have also been developed.
Narration: One way to store solar energy is in the form of a gas. That option is being explored at the Solar Tower facility at the CSIRO in Newcastle.
Mr Wes Stein: We have about 200 of these mirrors here and each mirror tracks the sun during the day, and focuses it up onto that tower.
Dr Paul Willis: Does it generate a lot of power?
Mr Wes Stein: It generates well over half a megawatt of energy up there, we concentrate the sun nearly 3,000 times on average, and we can generate temperatures well over 1000 degrees Celsius.
Narration: Once the power is harnessed, methane is pumped in and the sun’s concentrated heat forms new chemical bonds, trapping the energy.
Mr Wes Stein: Solar energy then becomes both transportable and storable, and that overcomes two of the major problems of solar energy.
Narration: Another storage option is using a different gas, ammonia rather than methane. The sun’s heat splits ammonia into hydrogen and nitrogen. These two gases can then be stored. As they change back into ammonia they give off the heat that was originally trapped.
Dr Keith Lovegrove: Inside here we’ve got our ammonia synthesis reactor. This is the reactor that gives off the heat that we’ve stored in chemical form in our tanks over there, gives off the heat at 500 degrees C.
Dr Paul Willis: The technology has come a long way. We now have a variety of ways to capture the energy from the sun and to store it for when the sun’s not there. So why may you ask are we not already living in a solar economy?
Narration: While these technologies are scientifically mature, they’re economically underdeveloped.
Mr Wes Stein: At the moment solar thermal is probably about two or three times the price that it needs to be.
Narration: And while that’s still the case, there’s little incentive for industry to roll out solar technology.
If you have a technology that is not producing emissions it is going to be more expensive than pulling coal out of the ground and setting fire to it. That is just a fact of life and so if we want people to use the emission free technology we need to give the market a signal to switch from one to the other, and so we need government assistance to drive those programs.
Narration: One way governments can provide assistance is to set energy targets that must be filled by renewable energy technologies.
The Federal Government set such a target in 2000 but critics say the target was set too low and so was the government funding.
Senator Ian Campbell: I spend a lot of time focusing on how we can ensure that for you know the literally hundreds of millions of dollars that go into solar technology in Australia from the Commonwealth government that we get even better returns and if there are new projects that we need to spend more money on then I’m happy to take them to the cabinet and try and convince Mr Costello and Mr Howard to spend more money.
Narration: Many in the energy industry think solar would get a big boost if the Federal Government would commit to an international emissions trading scheme such as operates in Europe. Companies releasing carbon into the atmosphere are taxed, creating a financial incentive for them to move from dirty to clean technologies.
Dr David Mills: Carbon trading makes immediate benefits to the bottom line for us. And so in our projects in Europe where everyone has virtually signed Kyoto we find that we add that to the bottom line and that improves the project economics. And of course we hope that the Australian government in due course will do that.
Narration: Carbon taxes and emission trading might help make solar more competitive, but that puts up the cost of electricity from CO2 emitting coal-fired power stations. Is that a price we’re willing to pay?
Senator Ian Campbell: You put taxes up on energy too much and you drive jobs down or you drive them offshore and you drive greenhouse gases offshore so you need to achieve what we’re talking about, about a sensible incentive system as I would call it without driving up costs and taxes.
Narration: Given the right incentives, Australia’s solar scientists are confident that, in 25 years from now, the solar future will have arrived.
Dave Holland: In 25 years time it is our mission to have our technology as one of the key ingredients in electricity production worldwide.
Mr Wes Stein: I think in 25 years time that solar thermal is making a significant contribution to Australia’s energy mix. It would only require about 50 kilometre by 50 kilometre square, in the centre of Australia somewhere, to supply all of Australia’s electricity needs in 2020.
Dr Keith Lovegrove: I believe the technology is in place that we could have 100% renewable energy in just a very short number of decades if we set our minds to it.
Mr Wes Stein
National Solar Energy Centre (CSIRO)
P.O. Box 330, Newcastle NSW 2300
Solar Systems Pty Ltd
6 Luton Lane, Hawthorn, Victoria, 3122
Dr David Mills
Solar Heat and Power Pty Ltd
Dr Keith Lovegrove
Department of Engineering (Bldg 32)
The Australian National University
Canberra, ACT 0200