Australia's renewable energy future
Bioenergy options for Australia
Tuesday, 3 March 2009
Dr Steve Schuck
Manager
Bioenergy Australia
Stephen Schuck has a PhD, an MSc (engineering) and an MBA (technology management). Through his company Stephen Schuck and Associates, he manages Bioenergy Australia, a government-industry alliance of some 70 organisations, fostering the development of bioenergy. He is Australia's representative on the Executive Committee of the International Energy Agency's Bioenergy program. He has been involved in numerous bioenergy projects, including market entry and biofuels and bioelectricity studies. Stephen co-authored the major report Biomass energy production in Australia: Status, costs and opportunities for major technologies.
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First of all, thanks very much for the invitation to come and talk to you this evening. What I intend to do is give you a pretty much whirlwind tour of bioenergy and how it relates to, I guess, an option for Australia.
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Just a few things to set the scene. I want go through what biomass is about; bioenergy. So to start off, biomass is material produced through photosynthesis that is not fossilised. That's a nice broad definition. It covers a whole range of material such as sawmill wastes, processing wastes from things like wood residues, agricultural residues. Bagasse is the residue after you have squeezed sugarcane for sugar production; agricultural straws. About three-quarters of the urban waste stream can be regarded as renewable. There are a lot of materials going in there.
Biomass also includes things like sewage and animal manures. Something that is not quite economic yet, but is getting there quite rapidly, is energy crops, be they woody or herbaceous type materials. It is interesting that woody weeds qualify under our national renewable energy target, even though you are trying to make it not renewable. You really want to get rid of the weeds, so it is interesting that woody weeds qualify as well.
Processing wastes, through the production of pulp in the paper industry; through pulp manufacture there is something called 'black liquor', which is basically rich in lignin, which can have energy extracted from it. And quite a hot topic in recent times has been algae, particularly micro-algae but also macro-algae such as giant kelp.
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These are just some examples. I intend to illustrate this presentation with quite a few photographs. What you are looking at there on the top left is from one of my travels. It is in Finland and it is on the grounds of a wood cabin factory: waste material from that process. Also shown there are some uprooted stumps. Bottom left is straw bail delivery at a plant, which I will go into more detail about, in Denmark, basically using agricultural straws and urban wood waste: examples of waste pallets.
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Just to set the global context. Bioenergy represents about 10 per cent of the global total primary energy supply. It is, by a long way, the dominant renewable energy source. And of that a good percentage is in developing countries where traditional biomass is used for cooking and heating.
The bit I want to concentrate on is on the right-hand side, the commercial biomass. An exa joule is 10 to the power of 18, so a one with 18 zeros after it. Dividing commercial biomass up into electricity, heat and biofuels, you can see the split amongst those.
What I have also written into that slide is the energy conversion efficiency and how much useful energy has been typically obtained.
Just noting, there is this big picture and focusing on bioenergy the size of about 63 billion litres (63 GL) of ethanol production globally and about four billion litres (4 GL) of biodiesel. I will come back to these in more detail.
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In setting the scene I want to explain why bioenergy is renewable. A lot of people say it kind of produces smoke. It is a combustion technology, how does it fit in? To get everybody at the same level, basically bioenergy can be thought of as a form of solar energy. It is an indirect use leveraging off nature. Through photosynthesis atmospheric carbon dioxide is captured in the biomass itself. Processing the biomass into either heat and power or transportation fuels, the carbon dioxide that was captured through the solar energy conversion – photosynthesis – circulates back through the biosphere turning into, hopefully, an equivalent amount of biomass through growth.
So this is nice and simplistic. This is how it is deemed to work under the Kyoto Protocol, and will be under the Carbon Pollution Reduction Scheme in Australia, as being carbon dioxide neutral.
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I would just like to take you a little bit deeper into this. When one starts doing detailed life cycle analyses, looking at all the energy embodied in the technology, the fossil fuels involved in the harvesting of the biomass' transportation and so on, what I'm presenting in this slide is a range of bioenergy like life cycle emissions in terms of grams carbon dioxide per kilowatt hour of electricity production. This comes from an international energy agency and was used in the Department of Trade and Industry UK study.
I need to explain that there is nothing definitive about life cycle analyses. Each case depends on how you draw the boundary. But hopefully these comply with standard practice.
To benchmark it, black coal in this particular study was 955 – so nearly a kilogram of carbon dioxide per kilowatt hour of electricity production. CCGT, which stands for combined cycle gas turbines – I will try to explain acronyms as we go through – about half that. A range of bioenergy – which I will go into in a bit more detail – from forestry residues either using steam cycles, anaerobic cycles or gasification, combustion turbines. What I have done there, to be perhaps a little bit provocative, I have included from this particular study photovoltaics for new homes and showing there it is quite a bit higher. This is associated with the embodied energy in the silicone and the framing and so on. I took this from a slightly dated study, but that is really why research is required to try and drive that down: to use thin form silicone cells instead of fairly thick wafers. What I am trying to say is that this is not a definitive study. But it is indicative and, I suppose, a bit of an eye opener.
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The other thing I would like to talk about, which has been embodied in legislation – and bioenergy is struggling to catch up with – is that you have two options in terms of addressing climate change. One is to grow trees and sequester the carbon dioxide: draw it out of the atmosphere through photosynthesis; have permanent plants. This is how the legislation works in New South Wales, for instance, under the NSW Greenhouse Gas Abatement Scheme. When you get canopy closure, the trees mature, you basically get this plateauing effect.
We, through Bioenergy Australia, commissioned a report to have a look at the role of bioenergy in carbon trading. This is an extract from it. Copies are available on the RIRDC website or from RIRDC, which is the Rural and Industries Research and Development Corporation at Barton. What is shown there is growing a short rotation crop. So basically you grow your biomass. Harvest it. Regrow it. Harvest it. And then use the biomass as a fuel. You are offsetting fossil fuel use. You are getting this accumulative benefit in terms of carbon dioxide emissions.
What I am trying to flag up is that bioenergy also has that advantage of actively managing the carbon and getting that continued offset.
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Just as a bit of a preamble, a number of what I have termed 'co-products associated bioenergy' such as renewable energy certificates, besides the electrons and the power production there are other environmental benefits such as carbon credits, which is going to come through the Carbon Pollution Reduction Scheme, saleable ash, for instance. It's interesting that the ash from, let's say, stem wood, doesn't have things like toxic metals in it, as coal ash has. So it can be used as a soil amendment and has actually done so in parts of the world, the fly issue, the soil amendment and the bottom of ash furnaces for road base.
Opportunities in terms of biofertilisers. There is a plant at Camellia near Parramatta in Sydney where they co-produce, through anaerobic digestion, electricity and also an ammonia-based fertiliser.
Opportunities in terms of fuels, methanol, ethanol – I will come back to this. Activated carbon. Opportunities for something called a bio-refinery as well with the co-production of heat, power and things like chemicals and so on: and related areas such as plant breeding biotechnology. Basically, capacity building.
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Something I have called 'co-values', and again perhaps I will just touch on a few of these, such as dispatchable power. It goes with hydro as well. What's a bit unusual for a renewable energy is that bioenergy can be dispatchable base load. Wind and solar tend to be dispatched by nature, when the wind is blowing and the sun is up, unless you have storage, which is an additional cost which is often ignored. Whereas biomass basically stores the energy in the chemical bonds in the biomass, and it can be released to meet peak demand on hot days when air conditioning is going.
Regional development and employment. There have been a number of studies done showing quite impressive economic multipliers in terms of job creation and regional development. Salinity and land repair: one of Australia's biggest environmental problems is dry land salinity, particularly in the Murray Darling Basin and Western Australia in parts of the sheep wheat belt. Basically if you can grow a deep-rooted or Mallee trees, you can use the biomass copers, cutting the trunks off at ground level on about a four or five year cycle. It re-sprouts, and is known as epicormic growth.
I will be a bit careful how I put this in terms of fire hazard reduction. It has been interesting with all the bush fires. This idea has been around for a little while. There are opportunities for removing some biomass and to reduce bush fire fuel load: instead of it going into the air with the pollution and things associated with it, to control it through technology and extract energy from it.
Biodiversity and animal habitat. The aim of the game here is growing more biomass, not vacuuming up forests or anything like that. There are huge opportunities here as well. Also waste management. One thing to stress is that bioenergy is often not just an energy system: it is often linked with other benefits, co-benefits, as well.
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Before we get to the technologies – I will just finish the preamble – biomass can come in many forms from very dry, say 10 per cent moisture content in something like grass or straw, right through to fairly wet like sewage stream, which may be 98 per cent water. So there is a requirement to mix and match the technologies. The main ones can be categorised in terms of thermal processing, which can be subdivided into combustion, gasification and pyrolysis – I will touch on each one of those with some examples in a moment.
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Combustion accounts for about 90 per cent of modern bioelectricity. It is very similar to coal fired power stations: burning biomass to raise steam, which drives a turbine or steam engine, and then drives an alternator.
Gasification uses partial oxidation, whereas combustion uses excess air. With gasification you produce a combustible gas which is carbon monoxide, hydrogen and methane. It's very familiar in Australia. Many towns and cities in Australia, until about the 1970s, had something called 'town's gas'. They produced combustible gas from coal reticulated. There are some wonderful historical monuments such as in Hobart and Launceston. Very similar for biomass. It is kind of early commercial stage.
Pyrolysis fractionates the biomass into products of char, a gaseous liquid and a solid component. It can be optimised for liquid production. You can get about 75 per cent of the dry way to the biomass into this liquid form. It has something like 60 per cent of the energy content as diesel on a volume for volume basis.
I want to talk about biochemical. This is using microbes to convert biomass, usually wet slurries and so on, into a gas rich in methane and carbon dioxide. Very familiar in landfills. Australia disposes of most of its waste in landfills. Landfill gas is about half methane and half carbon dioxide. You can run it through spark ignition engines and produce electricity. In Australia there is about 170 megawatts of landfill gas generation.
Fermentation, you will be well aware, produces ethanol, and that can be used as a transport fuel or a fuel additive. Also by adding vegetable oils you can change the viscosity of it so it runs better in conventional engines and produce something called biodiesel.
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So with the combustion technologies, this diagram is more or less to scale. Grate furnaces are fairly familiar. You introduce fuel onto a grate. It can either travel or vibrate to move the fuel across. You extract the energy into tubes to raise steam. There is something called a fluidised bed combustor where you have a bed of sand-like material running at about 850 degrees Centigrade; lower temperatures than you would get in the open space in a furnace.
It has advantages in terms of the wide variety of fuels you can burn and also for controlling emissions of sulphur dioxide, oxides and nitrogen, which is NoCS, usually associated with brown haze. There's also an opportunity for dust firing where you convert your fuel into talcum powder-like substance. This is very common for coal, but can be done with wood pellets as well.
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One thing that is getting quite a lot of currency, particularly in the northern hemisphere, is something called wood pellets, which is a pre-processed fuel. One of the big limitations of bioenergy is the supply logistics of transporting quite low density fuels. Wood chips would have a density of only about 120 to 200 kilograms per cubic metre. By reducing the moisture content and producing these pellets – it is something like a big mince meat making machine you can see that produces these little pellets – you can get the density up to about 650 kilograms per cubic metre in bulk, and get the moisture content right down. So it becomes quite a premium fuel, commanding a price of about 200 Euros a ton in Europe.
It is transportable, with quite a big international trade. There's about 10 million tons of these wood pellets now being used, growing at about 30 per cent per annum.
There is an Australian company set up in Albany that plans, for Mount Gambia and the Green Triangle in Victoria, to create an export industry to bypass some of the difficulties in the Australian market – which I will get to.
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So just how are these pellets used? There is quite a big heating market in the overseas market. This is an example of a little village central heating plant in Sweden. We don't have a great requirement for heat in Australia, but this could also be used for cooling.
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These are basically woodchip boilers. They are quite small: you can see the scale of them. They are quite common overseas where you have carbon dioxide taxes and prices on carbon, and are becoming quite popular.
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This slide shows a milk processing plant I visited in Switzerland. They replaced their fossil fuels with this biomass boiler. It is in a clean room: you had to don special protective gear to go in. The fuel, woodchips, is fed in through a grate in the sidewalk. Stem wood has got extremely low ash, which is the incombustible material. This horizontal auger over there [pointing to slide], that is basically removing the ash.
The ash content of stem wood may be as low as about 0.4 per cent. Whereas in a coal fired power station they would be as high as the mid twenties. So you don't have a requirement for ash dams with bioenergy. In fact, the ash is usable. As I mentioned, it can be sold as a soil amendment.
What I want to do is just go through in terms of how big bioenergy can be. This is quite a small scale, using the heat.
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This is an Australian example. This is at Gympie in Queensland where they have set up a small bioelectricity plant using macadamia nut shells at Sun Coast Macadamia. It's a 1.5 megawatt project running on a stream turbine. It was set up by Ergon Energy – it is now owned by AGL.
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Moving up in scale. This is an example from the Central Valley in California using mainly uprooted walnut trees, but also the wood waste coming out of San Francisco. You can see the fuel supply delivery. You get about 30 to 40 of these semi-trailers coming through the gate each day dumping the fuel. That plant is in operation.
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This is quite an interesting example from the Netherlands. It is at the intersection of a number of canals, near the German border. One thing that is quite fascinating about this plant, it is a bubbling fluidised bed boiler. Those conical buildings are fuel silos. You can see some fuel over there [pointing to slide]. It uses dry cooling. One requirement for steam-type technology is that you need to condense the steam, and this can be done either through evaporative cooling using lots of water – as it is done in Australia. This particular plant, in spite of all the water around it, uses dry cooling. Not too dissimilar in concept to a motor car radiator.
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This is just to prove it is in the Netherlands with a windmill right flat bang in the middle [top left image]. Talk about heritage value. This is the bottom of the coolers. The big fans are probably close to 10 metres in diameter. The interesting thing about this plant is that it runs unattended overnight. It is remotely controlled over weekends and overnight from about 50 kilometres away. You see the fuel delivery [bottom right image] with drivers bringing their fuel load in with a swipe card. They weigh themselves in, and weigh themselves out: the difference is how much fuel they get paid for.
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This is another Australian example, going up in scale. These are two 30 megawatt plants. Rocky Point Sugar Mill in south-east Queensland is Australia's oldest sugar mill. It was converted about eight years ago to run on bagasse, year round. Because of the crushing season, the bagasse is only available about six months of the year. It actually supplemented the fuel supply using urban wood waste.
Two new power stations have just been commissioned in the last year: one at Condong Sugar Mill and another one at Broadwater. The two northern-most sugar mills in New South Wales are using this modern technology.
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Going a little bit further up in scale to 36 megawatts. This is in Michigan in the US. This is one plant that is actually using the fly ash as a soil amendment in that state.
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Going up a bit bigger. Kettle Falls in Washington State in the US is 47 megawatts.
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You start plateauing in the US at 50 megawatts, which is this plant in northern California. This one is a bit unusual because it has got what is known as a stacker/reclaimer, which is quite common in the coal industry. There is one, for instance, on Kooragang Island at Newcastle for exporting coal.
When they set up the legislation for bioenergy in the 1970s – and this plant goes back to then – there was some legislation which limited the size of plants to 50 megawatts. That has only now been broken in the US.
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Shifting to Europe, this is in Finland. Just to show the scale of some of these plants, this is at a pulp mill on the west coast of Finland. It uses a circulating fluidised bed combustor – sorry for the jargon – and you can see in this diagram the size of a person [circled area on image at top right]. This is now approaching the scale of Australia's big coal fired power stations. This particular plant can run from 100 per cent coal to 100 per cent biomass.
It incorporates the world's first train for moving biomass. It uses something called slash bundles, which you can see on this train. The fines from the harvesting – the logging activities – are collected through a special purpose forestry machine which compresses and braids bundles. I guess you can call them synthetic logs that can then be transported on conventional log forwarding and forestry equipment.
You can see at the bottom of the large diagram on the left some of these bundles stacked, and other types of wood waste.
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If anybody has been through a coal fired power station, a person looks a little bit like an insect on its back. This is the turbine hall, 240 megawatts electrical, just to show the scale.
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Switching examples now, this is a plant just south of the airport in Copenhagen. It has an interesting history. The plant in the foreground is a coal fired unit. You can see the coal yard over there [pointing to slide]. When they came to design and build the second unit for this other plant [two plants close together], halfway through the design they actually switched to biomass. So the second unit, which is slightly bigger and behind the first one, was set up as what is known as an ultra super critical boiler. This is technology which uses extremely high temperatures and pressures of steam that goes beyond what is known on the steam diagram as super critical – it goes past the critical point.
There is an example of it in one of the most modern power stations in Australia, at Koorong North. They are using extremely high temperatures and pressures associated with additional conversion efficiency of fuel energy to electricity. So this plant is right up there with the scale of our largest coal fired power stations. It was opened in around 2002.
It is a cogeneration unit, or combined heat and power (CHP), and can produce simultaneously 505 megawatts electrical and 565 megawatts thermal energy for district heating and for running the industry around the area. In purely electrical mode I think it is 590 megawatts electrical. It is an interesting plant. It is multifuel. It includes a separate straw boiler. Agricultural straw is associated with corrosion and fouling of a boiler tube, so there are special design considerations, and you put it in a separate boiler.
They also have some gas turbines, where the exhaust heat goes through the boiler as well. They use an awful lot of wood pellets in this particular plant. It is basically using a combination of straw bales. If you recall, one of my earlier slides shows a truck unloading straw bales. That is from this power station. Those big units over there, they are actually big thermos flasks and it is storing hot water for reticulation around the local area. By doing this you can get about 94 per cent overall efficiency. Whereas our big modern power stations in Queensland and New South Wales are at about 38 per cent on the same basis.
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One interesting variant which complies with our legislation is co-firing biomass with coal. It saves you the capital cost of a unit. Basically you can piggyback what is there. Here are two examples from Australia. On the left is the Swanbank Power Station at Ipswich in Queensland where they set up a bioreactor cell, which you can think of as an engineered landfill, take some of the combustible gas and burn it in the furnace. Shown on the right is Wallerawang Power Station near Lithgow in NSW, which is dumping woodchips onto coal conveyors.
We can do this only at a small percentage because these plants are designed specifically for coal. There are about 150 power station units around the world co-firing.
In Australia, if the biomass complies with regulations you can get renewable energy certificates under federal legislation. Sad to say this does not qualify for green power, because the rules stipulate that the overall power station needs to be more than 50 per cent renewable energy.
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Now I would like to talk about gasification. There is a whole range of technologies and scales which I have shown on this diagram with different efficiencies. As the technology gets more sophisticated you can get more energy out of it.
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This shows the different variants of fixed beds and fluidised beds, but I won't dwell on that one too long.
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On the right-hand side is an example from Australia. This is in the Huon Valley in Tasmania at the Tahun Area walkway. This is a small downdraft gasifier that was imported from India. Dual-firing some diesel gensets in this isolated power supply. They produce this combustible gas, which I mentioned was rich in carbon monoxide and hydrogen. They feed it into the air intake of the diesel gensets, back off the diesel. Let it run on about 80 per cent gasified biomass and then you can reverse the process when you shut it down.
Another example is on the top left. This technology is replacing the diesel tank, basic gasifying of biomass.
Bottom left is an example from Croydon in the UK of a newly opened renewable energy project with a gasifier on the inside and photovoltaics on the roof.
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Some research going on in Italy, just to show you the scale. I want to get to some of the commercial projects.
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There is something called BIGCC – don't get scared by the names – Biomass Integrated Gasification Combined Cycle. That means that you gasify your biomass, run it through a combustion turbine to produce power, recover the heat that comes out of the exhaust of the gas turbine, and raise additional steam to produce, through a steam turbine, additional energy. So you get two bites of the cherry from your fuel to produce electricity and also thermal energy. This plant was set up about a decade ago – more, thirteen years ago – in Sweden as a proof of concept plant at a commercial scale. It ran for several thousand hours in gasification mode and also in full integrated mode.
It was an air-blown project. You need to gasify using a medium, either steam, oxygen or air. This plant ran successfully and is now being turned over for biofuels research.
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Here's an example in Austria. This is an interesting plant. I will come to the technology in a moment. It was sited in this particular area along the Hungarian border because it was an economically depressed area of Austria and because of the economic multipliers that I mentioned in terms of direct, indirect and induced jobs. It was set up there to stimulate the local economy. Perhaps it is something that our policymakers and shapers could think about.
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And this is the footprint of it, just to show you what they are doing. What I didn't mention previously, and perhaps it is getting a little bit technical, but gasification is an endothermic reaction. Combustion is an exothermic reaction. So gasification requires heat; combustion gives off heat. So by close coupling these technologies you can get efficiencies which allow you to get a greater calorific value for the gas that is produced.
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This diagram is more like the physical manifestation of it.
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This is what it looks like on the ground, getting a bit closer. It produces 2 megawatts of electrical power. It is limited to that because the Jenbacher, which belongs to General Electric out of the US, provided the engines. The size of their two engines was 1 megawatt each at that time. It has quite impressive conversion efficiency for that scale of plant. And again, it can run as a combined heat and power plant.
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This is an interesting one from the Netherlands. This is a hybrid between gasification and co-firing, which I mentioned before. This power station in the Netherlands is a 900 megawatt unit. This view [bottom image] is taken standing on the roof of that [top image] unit. They have set up this little satellite gasifier. Instead of just putting the woodchips on the conveyor, where you are limited to quite a low percentage, they have set it up so there is the fuel silo and the gasifier. The combustible gases are fed into the furnace and you can see the pipes for the thermal energy and the combustible gases coming across over there. That is another shot of it. It provides about 83 megawatts thermal energy in this particular plant.
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The other thermal technology I wanted to cover was pyrolysis bio-oil. You can use bio-oil for a boiler fuel, or extract for transportation fuels or refine for chemicals: value-added fine chemicals.
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This has been an advanced research area and it is now reaching commercialisation.
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A company in Canada called Dynamotive has been using this small rugged gas turbine for firing bio-oil. It is very different. It is called bio-oil but it is really different to what you would associate with, say, petroleum oils. The turbine is sitting in that cubicle and producing electricity.
There have also been tests done running it in dual fuel mode, which I mentioned a bit earlier, in big rugged reciprocating engines.
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This is the progression of their technology development from pilot scale to 2 tonnes per day, right up to 200 tonnes of biomass per day. There is an Australian company called Renewable Oil Corporation which has the licence from this company and is trying to set up a project in Victoria.
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Anaerobic digestion. There's a whole range of sizes. This can be from literally a bag of poo to a big industrial complex. Here are some examples. The top right is a dairy farm in Switzerland. Bottom left is in the Philippines, and there are examples from the US and Austria. You get the combustible gas, and as I mention, Australian landfill gas produces about 170 megawatts.
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Here's a summary of some of these technologies in terms of their energy conversion efficiency. I want to skip through to biofuels, which is quite a topical area.
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A lot of you would have probably heard about the 'food versus fuel' debate and first generation biofuels. I would like to say it is a media beat-up, but it is an interesting development. For first generation biofuels materials that are associated with food crops are used. In Australia we essentially just use waste.
We use starch waste and manildra for producing ethanol, and also molasses out of sugar refining processes, which is again relatively low value product. So in Australia, there is only now one grains-based plant that has come online in Dalby in southern Queensland, and the Dalby bio-refinery uses sorghum grain.
What you get there is ethanol which is blended with petrol, or bio-esters which are generally biodiesel, which can be blended into diesel at fairly low levels. The second generation is to try to broaden applicability of the feedstocks to use things like urban wastes.
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First generation biofuel is well developed, particularly in Europe, using grapeseed oil or canola, where farmers are paid not to grow food. So it is a bit of a macabre subsidy. And ethanol, which is very well developed in Brazil and USA.
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On one of the Bioenergy Australia conference tours we went to visit a plant in Western Australia, which is sadly mothballed at the moment.
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The conventional production process for ethanol is very well established through fermentation processes.
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What I wanted to mention is that biogas can also be used as a transportation fuel. About half of Sweden's automotive gas is actually biogas. The image on the top left is from just outside Los Angeles: they liquify biogas with a methane component of it and then run it in heavy transport. It is quite an interesting version. And there is also the world's first train that runs on biogas in Sweden.
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Second generation. From biomass you have two possible routes. Through fairly sophisticated and developing technologies for liberating the sugars – mainly pentose and hexose – which can be converted to ethanol. The other route goes through a thermal process of gasification. You get the chemical feedstock of carbon monoxide and hydrogen, produce syn gas and then produce things like synthetic diesel. South Africa has been doing this with coal at Sasol plants for many decades.
Something called DME, dimethyl ether, is produced in New South Wales for natural gas – not for fuel but something that Volvo is exploring quite seriously – and also methanol.
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Basically these are the two routes: biochemical and thermochemical.
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This is an example of a plant in southern Germany at Freiberg, where Volkswagen, Choren and Daimler Chrysler have teamed up to produce this Fisher-Tropsch. It is the name of the catalytic process of the synthetic diesel.
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There is a whole roll out of gain, from these first generation biofuels through to something called 'green diesel', where you can add hydrogen and alternative processing. The feedstock is renewable: you don't end up with biodiesel, but something very similar to a synthetic diesel, of slightly lower density.
Higher alcohols. There is quite a lot of work; BP is working on biobutanol. The Fischer-Tropsch fuels I mentioned. The pyrolysis area. These are things that are developing. We have quite a crunch coming in terms of peak oil, in terms of the sustainability, the carbon dioxide emissions.
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I am often asked the question, 'Don't some of these fuels actually emit more greenhouse gases than petrol?' This summarises some work that came out not too long ago from the European Joint Research Centre in the Netherlands. It shows emissions in terms of grams CO2 equivalent per kilometer. Some of the first generation biofuels give something like a 30 per cent greenhouse gas advantage over fossil fuels, depending on whether the feedstocks are waste, how much fossil fuels need to go into the production and the fertilisers. All this is built into this type of study.
The second generation biofuels can give something like a 90 per cent reduction. There is a swag of these projects. The US is putting about a billion US dollars just into the development of second generation biofuels. In Australia, I am pleased to say, we have a $15 million second generation biofuels program, which is about to go into the assessment mode for projects.
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This shows some of the emerging technologies in terms of heat and power. Stirling engines are well-known: invented probably well over 150 years ago. It is only now that the technology is catching up that you can actually make it work. The problem is you need gases like helium against small molecular weight gases to seal in at very high temperatures.
So that's two examples of Stirling engines that are gradually getting into the market.
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Organic rankine cycles have been developed for waste heat recovery. Here is an example of this technology from Austria .
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Some development challenges remain. One of the big challenges is to densify the biomass to improve the economic catchment area and economics in terms of pyrolysis and pelletisation, which I covered earlier.
Torrefaction is more research orientated. You can think of it as green charcoal, which then is more mean level for transportation and milling. I mentioned organic rankine cycles [ORC] and Stirling engines: they are in the demonstration phase. Steam cycles, are commercial. Integrated gasification fuel cells operation. I believe you had Karl Foger talking about fuel cells.
I've covered co-firing technologies. An interesting area is microbial fuel cells: producing hydrogen that goes straight into fuel cells. Quite a bit of work going on at the University of Queensland I'm aware of.
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In terms of jobs; this comes out of a slightly dated European Union research project showing a range of bioenergy job prospects or projections, showing that against wind energy.
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This covers implementing bioenergy in Australia. I was asked to talk about this as well. The key drivers are renewable energy targets. The legislation is pending. We have a little run on renewable energy certificates. There have been a number of studies showing what bioenergy could produce. I have some copies of this roadmap [Clean Energy Future for Australia] – a very limited number, but it is on the web. There is some data on the CD at the back. I also have some Bioenergy Australia newsletters, again available on the website, and some fliers as well.
We also have a fairly soft biofuels target. I think the Henry taxation inquiry will look at that as well. It has tax implications in terms of excise, holidays and things like that.
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One of the barriers to implementation in Australia is the low cost of fossil fuels, our coal. Australia is usually quite proud of that, but it has been an inhibitor for renewable energy. Perhaps is a bit of the cause of the problems that we now face climate-wise.
Another barrier is the awareness and understanding of bioenergy, for example the policy makers and shapers. It is quite a difficult message to get across. It is really easy to explain the concept of solar energy or wind energy. But I think I have shown you that there is quite a bit of complexity to bioenergy. It is a bit fractal: as you start homing in on it, it kind of opens up in front of you.
There are concerns about logging native forests, particularly at the political level. For that reason, in all of the mainland states when there is a logging operation going on that totally complies with all regulations you cannot use the logging harvesting residues for bioenergy, you can only use post-processing. So a lot of that is scraped into a pile and burnt and left on the forest floor, waiting for the next bushfire.
Sustainability issues; food versus fuel and water are important issues. The economics of fuel procurement. I mentioned the density issue, and it is much easier just finding a fossil fuel in the ground and digging it out rather than actually growing your own or recovering it from a waste stream. And some of these project lives are capital intensive, in that you need 25 years to recover the capital on equipment.
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So in conclusion, there is about 44 gigawatts of modern bio-electricity. That is about the same scale as Australia's total coal-fired power industry. It is well developed and I have shown you some examples. In Australia we have [the capacity for] about 700 megawatts [of bioelectricity]. I think Australia is currently producing about 50 gigawatts, so it [bioelectricity] is about 1.5 per cent or thereabouts of the mix.
I mentioned the fuels. Australia has got a fairly low target at the moment of 350 megalitres by 2010. I believe there is a large unrealised potential in Australia.
Could I invite you, perhaps, to have a look at the Bioenergy Australia website, which is www.bioenergyaustralia.org. We have these newsletters. There are about 35 copies. It is meant to be an electronic copy but I have very limited number of hard copies over there.
We got involved in the Clean Energy Council's process funded by the Department of Environment, Water, Heritage and the Arts. This produced a roadmap of stationary energy. The sister academy, the Academy for Technological Sciences and Engineering, did a roadmap for biofuels. I think there are quite good prospects. And I think I beat the 10 fingers.
Discussion
Chair (Mike Dopita): Yes, you did indeed. I have a new appreciation of just how complex and many faceted this whole area is. There is a lot of homework to do there.
I am going to open the floor for questions. There are a couple of runners with microphones. I ask you to keep your hand up until a runner has actually brought the microphone to you so we can keep the pace of the questions going rather rapidly.
If I may start with the first question, because it is something that I am kind of interested in. If we were to try to make biofuels run our transport, how much of a percentage could we do with that just from biofuels?
Stephen Schuck: It is an interesting question. The CSIRO actually conducted a study. I think that is on the RIRDC website done by Deb O'Connell and others. There are a whole lot of assumptions one needs to make. What does one do with agricultural production? So they had a look at what happens if we don't export wheat and things like that, we convert it into fuel; and what are the opportunities for second generation biofuels? It ended up at the top end of the scale with 140 per cent of our total current fuel requirements basically going into this second generation biofuels to quite a low level. You don't get much – I don't know, several percent. I don't have the record with me.
But it is taking baby steps first and getting it in as a fuel additive rather than trying to run the whole economy. I think the future is going to be a portfolio which may include electric vehicles, hybrids, biofuels and hydrogen. So it is hard to tell.
Question: Good evening. I'm just interested in the comment about using forestry residual materials. My understanding was that there is an issue there. In terms of if you pelletise all of that you lose the nutritional value, and it is actually quite expensive to replace the nutrient value for ongoing cropping of that land then?
Stephen Schuck: Bioenergy has been running for a long time. This is not a new issue and something specific to Australia, although we have some unique conditions. Most of the nutrient in biomass is in the leaf matter and the fine twigs and material in the bark. Often that's left behind. So the best bit, I guess, for the fuel is actually the stem wood, which has extremely little nutrient.
There have been a large number of sustainability studies and some of it has been in terms of leaving a certain amount of material, putting material on the ground to avoid compaction. That's another problem; if you compact the soil you will damage the biomass.
In Scandinavia it is quite common also to spray the ash back into the forest for replenishing nutrients. So it is a case of trying to balance things out. You can't obviously take out too much. There is a lot of science required to get the right balance.
Question: Thanks, Dr Schuck. I just wonder about the setting of targets, renewable energy targets, by successive Australian Governments has been a source of great disappointment to many people associated with renewable energy. What is it that Bioenergy Australia is going to do? What plans, what strategies are you going to employ or approaches do you have in mind to sell the message about the possibilities of bioenergy and biomass both to the broad Australian public but most specifically to our wise and wonderful politicians who have the power to set those renewable energy targets?
Stephen Schuck: Perhaps what didn't come out in the introduction is that Bioenergy Australia actually was formed by the Australian Government as a government industry forum. It started off as something called the Biomass Task Force in 1997. We subsequently expanded our membership to include state-based, government-type enterprises, plus the private sector. At the moment about half our members are from the government sector, half from the private sector. And we have, I think, about eight universities involved as well.
For that reason we have to be quite careful in terms of not being seen to be lobbying government with government money. So we have a bit of an issue. The way that is overcome is that I, as a consultant, put in submissions on behalf of the majority of Bioenergy Australia to various processes, such as the renewable energy target. There have been quite a few of these processes, making it quite clear that these views do not necessarily represent the views of all the members, to basically try and decouple that.
Having said that, the model that I have tried to create for Bioenergy Australia has not been, 'The industry association have given you a story, go to the gates of Canberra and deliver your message with meetings with the appropriate senior bureaucrats and politicians', but rather a model of sitting shoulder to shoulder through Bioenergy Australia meetings. So, for instance, we generally hold three day-long meetings in Canberra. We try to engage as many people from government departments as we can to share experiences, and to use that as an opportunity for explaining what bioenergy can achieve, and for government also, through their presentations at these meetings, to try and indicate to industry what their targets are, what their policies are and how industry can meet them. So it is a kind of mutual collaborative from the inside rather than, let's say, the harder advocacy lobbying type role.
Question: I'm very glad that Australia's concentrating on wastes as a source of fuel. It seems to me ethically and unsupportable that the United States should be growing corn to produce fuel when there is so much food shortage. There's one example of using food waste creatively and that is the Borough of Woking near London where the CEO has actually reduced the carbon footprint of Woking by 80 per cent in a decade.
He has collected all the food waste from restaurants and runs the public transport system on them. He has been very effective in that. He is now CEO of the London Climate Reduction Policy.
It seems to me ridiculous that there is so much food that is wasted in hospitals, restaurants, markets and so on that is just transferred to landfill, which is a very inefficient way of producing methane. Can you imagine a new stream by which organic waste from food – which is really an indictment of our society, but it is an enormous amount of energy thrown away – a stream whereby we collect all these things and convert it into biofuels?
Stephen Schuck: That is actually happening already. The plant at Camellia in Sydney that I mentioned – I think it is 80,000 tonnes per year. It has been set up as a food waste digester. It has been located in that area because it is close to the Flemington produce markets. They take waste material from there. They also, for instance, take material that is confiscated at the airport, and also out of spec [specification] food. I was once in the factory and I think there was a big crate of Arnott's biscuits, or something like that, that was running through this digester.
So it produces electricity. They use the biogas for producing electricity so it earns renewable energy certificates. I think it is about 3 megawatts. They also produce this ammonia rich fertiliser as well. So it has been done. In Sweden, half of the automotive gas in that country is from biological sources. So basically they are doing exactly what you are advocating.
Chair: I think a McDonald's grease burger combustion plant would be probably better for this society.
Question: You spent nearly all of your lecture talking about the possibilities of biomass. You said near the end that biomass was producing about a quarter of the RECs [renewable energy certificates] in Australia. But I can't understand why biomass isn't a lot bigger, particularly as we are talking about this in one of the biggest agricultural producers in the world. The Redding report about 10 years ago predicted biomass would be the dominant renewable energy type in Australia, but it is not – wind is.
And I can't understand why we use a lot of sugar waste in biomass production but virtually no wheat waste, wheat stubble, in biomass production. The amount of wheat stubble waste must be enormous in Australia, but pretty well none of it is being used.
You admit in the Clean Energy Council roadmap that stubble has the potential to do a lot of biomass heavy lifting. So why is it that biomass isn't bigger, and what's the big block to using wheat waste? Is it this densification issue?
Stephen Schuck: I think it's part of it. I'm not an agricultural expert. The bagasse tends to appear at virtually a point location at the sugar mill. Whereas a lot of these wheat straws and corn stub and those kind of agricultural residues, rice straws, are actually distributed around rather large paddocks. So you need extra equipment to collect it at additional cost.
So two reasons are the supply logistics and the cost of it. I think Stanwell Corporation got quite a long way down the track at one stage in developing a rice straw, or a rice wastes, about a 10 megawatt power plant in the Riverina.
It's certainly been done overseas, collecting it. But you need the right economic incentives. And the first, I guess, tranche of bioenergy is likely to be the point sources of waste, things like saw mills where you have the material already there.
Another thing is that agricultural straws tend to be associated with chlorine and alkali metals which imply corrosion and fouling of boil tubes. It is not the nicest material to work with. So you need special designs that cost more. It is interesting to note that Macquarie Bank actually owns the largest straw fired power plant in Europe, which is in the UK.
Chair: Yes, they are burning securities.
Question: Did the Stanwell Corporation follow through?
Stephen Schuck: No, Stanwell ran into problems at a management level. They moved out of renewable energy. They sold off the Rocky Point project, which they developed. They sold it to Babcock & Brown at the time. They are still running quite well at that particular plant.
Yes, so, the other thing that happened was the mandatory renewable energy target. There are a few things perhaps I can address. When the renewable report was done all we knew about biomass is that there was going to be a compliant form of renewable energy called bioenergy. When it came back out of parliament there were all kinds of requirements placed on it, like the chain of custody of biomass, mainly associated with concerns about using native forest residues, which provided quite a bit of an impost on the supply chains and the auditing requirements. So that made it a little bit more difficult.
Chair: Just time for two or three more questions. Is there one up in the dress circle there?
Question: In terms of cost per watt of electricity produced, can you tell me what the cheapest form of bioenergy is at the moment that is commercially available, please?
Stephen Schuck: I would probably say it is biomass co-firing of coal because somebody else paid for the capital equipment. So if you just chucked one little lump of biomass on the coal conveyor and stood back and watch it go through the furnace that basically cost nothing.
It is also very scale dependent. There is a big scale, like economy of scale, that applies to these units. Usually when you double the size of a power plant the per unit production cost is 85 per cent of what it was before.
So if you have a plant at, say, a kilowatt's scale, that has gasifiers and those things, that could be relatively expensive. But, again, it depends where your fuel is coming from. Typically the fuel cost could be 50 to 60 per cent of the total energy cost. It is obviously very dependent on what you are using. Are you using a waste? Are you growing a purpose-grown energy crop? What is the technology? There are a whole lot of factors.
Question: I recall it in an issue of the National Geographic magazine a few years ago they were claiming that algae can sequester carbon dioxide and be used for biofuels with an efficiency about 5,000 times greater than corn. Can you speculate about what the future of algae is going to be?
Stephen Schuck: Yes. I put it into my first slide and didn't really come back to it. Biomass Australia held quite a successful algae seminar just under a year ago. We had about 125 people turn up, including researchers from ANU. It is a hard one. There is intense research at the moment. It was a subject that was covered quite well after the '73 oil crisis for about 20 years, until it was realised that the price of oil wasn't coming down and the US Air Force could solve any oil shock.
Things changed after that. There is a lot of work going on now. There are some big issues in terms of economics of harvesting and getting light into certain areas. So there is work going on on so-called 'race course' reactors. It looks a little bit like a pony track. And SARDI, the South Australian Research and Development Institute, is doing quite a lot of work on photobioreactors. They have got funding under ENCRIS, which is Federal Government's National Collaborative Research Infrastructure Strategy. I happen to chair an access and strategy committee for AUSbiotech related to that.
It has probably got, my guess would be, about five years before there is a bit of a shake out and it becomes a bit more apparent where the low cost production is going to be. But algae oils are already being used as part of the fuel for flying big commercial aircraft.
Chair: Our final question down the front here.
Question: Thank you, Mr Chairman. Perhaps just as well that I am the last question. I want to congratulate you, Stephen, on teaching us so much about bioenergy in such a short time, under the dominant eye of the Chair who was making you hurry up.
My question is this: casting a broader view of alternative energy sources what would be your view of, say, Australia in 20 or 30 years of the contribution that bioenergy might make towards the total energy needs of Australia compared with sustainable options like solar, wind and hydro and, of course, compared with traditional sources? Where does bioenergy fit in in the future Australia?
Stephen Schuck: There have been a few studies that have had a look at that. The Clean Energy Council one mentioned that there would be a four-fold increase by 2020 from where we are at the moment. So that is up to about four times 700 megawatts. Bioenergy Australia funded a study that was conducted partly at ANU, and the Australian Institute was involved. But it was mainly headed by the WWF. This goes back about three, four years ago. Some of you may know Mark Diesendorf is one of the consultants that worked on that study.
It looked at what we could produce from renewable energy sources without a leap of faith. In other words, technologies that we already knew about without too much inventiveness being required.
The deep cut scenarios for 2040 came up with a number of 29 per cent of the generation mix in 2040. That was a 60 per cent reduction could be from bioenergy. That included, I think, 25 per cent was electricity only and the other 4 per cent were in cogeneration plants.
So that study is on the web. It is called Clean Energy Future for Australia.
Chair: Well, I would like us all to thank our speaker. He has given us a really excellent education in bioenergy. Put your hands together.
