Zero Carbon Australia plan - a reality check
The renewable energy advocates (and the Greens apparently) must be very pleased. Particularly Bob Brown judging by his opinion piece last week. The University of Melbourne in conjunction with Beyond Zero Emission (BZE) have solved all the problems with getting renewable energy to run our entire electricity network.
Their recent report called Zero Carbon Australia Stationary Energy Plan is a very impressive document that seems to have all the “i”s dotted and the “t”s crossed. The authors have spent hundred of hours carefully explaining how we can harness renewable energy to provide all our energy needs by 2020.
In the plan, all the energy we currently get from fossil fuels is replaced with energy from renewable sources. This means all the fossil fuels we burn in our vehicles and all the coal and gas we burn in our homes and factories will be replaced. Nothing is spared. And this is intriguingly done by converting everything to run on electricity and making all that electricity using the sun and the wind and some discarded crop waste. Simple, clean and easy to understand.
OK, sounds great, but what’s the cost?
Well not much really. Only $8 per family per week. Oh - but there are a few drawbacks.
First, the authors have made a number of assumptions to get the cost down to $8. The good authors have not made any attempt to hide any of these assumptions. They are all clearly spelled out in the plan to anyone prepared to plough through the 194 pages to find them. As many of you will not have the time (or perhaps the inclination), we have done the job for you.
For the $8 a week extra on your electricity bill, you will give up all domestic plane travel, all your bus trips and you must all take half your journeys by electrified trains. This will allow all you two-car families to cut back to just one electric car.
But can we trust it will only cost $8 a week more? This is where it gets a bit more complicated.
Unfortunately the authors seem to have developed the plan around getting the cost down to a price that should be easy to sell. This is where some of the assumptions start to unravel. -
The plan assumes we will be using significantly less energy by 2020 than predicted by the government department ABARE. What’s more, the plan believes we can reduce this energy use without any damage to the economy. Unfortunately, this flies in the face of 200 years of history.
You better stock up on candles because you can certainly expect more blackouts and brownouts with the ZCA plan. Our analysis shows that insufficient generating capacity has been allocated to maintain reliability in the electricity networks. Fortunately our responsible network operators will not let that happen.
We even crunched a few numbers to see what it would actually cost to address these issues. The bad news is it could add more like $50 a week to your power bill not the $8 promised by BZE. Ouch!
These are the conclusions from our analysis:
• The ZCA2020 Stationary Energy Plan has significantly underestimated the cost and timescale required to implement such a plan.
• Our revised cost estimate is nearly five times higher than the estimate in the Plan: $1,709 billion compared to $370 billion. The cost estimates are highly uncertain with a range of $855 billion to $4,191 billion for our estimate.
• The wholesale electricity costs would increase nearly 10 times above current costs to $500/MWh, not the $120/MWh claimed in the Plan.
• The total electricity demand in 2020 is expected to be 44 per cent higher than proposed: 449TWh compared to the 325TWh presented in the Plan.
• The Plan has inadequate reserve capacity margin to ensure network reliability remains at current levels. The total installed capacity needs to be increased by 65 per cent above the proposed capacity in the Plan to 160GW compared to the 97GW used in the Plan.
• The Plan's implementation timeline is unrealistic. We doubt any solar thermal plants of the size and availability proposed in the plan will be on line before 2020. We expect only demonstration plants will be built until there is confidence that they can be economically viable.
• The Plan relies on many unsupported assumptions, which we believe are invalid. Two of the most important are:
1. a quote in the Executive Summary: “The Plan relies only on existing, proven, commercially available and costed technologies.”
2. solar thermal power stations with the performance characteristics and availability of baseload power stations exist now or will in the near future.
Of course we don’t have to pay such a hefty price to replace fossil fuels. If our government would allow it, nuclear power can replace all fossil fuels for an increase on our power bills of probably less than $5 a week. How about it Bob?
Monday, August 16, 2010
Tuesday, July 6, 2010
Op-ed piece in Online Opinion. 6 July 2010
Addicted to fossil fuels
The recent oil spill catastrophe in the Gulf of Mexico could be an energy game changer. In a speech from the Oval office a few weeks ago, President Obama urged a transition away from fossil fuels and towards clean energy. This raises three very important questions. What is clean energy? Which clean energy can really replace fossil fuels? And how much will it cost?
Our new prime minister might want to ask herself these questions as she plans her own actions on climate change.
The world is not only addicted to fossil fuels; it’s addicted to a high standard of living delivered by cheap energy. Replacing fossil fuels means deciding on big changes to two large energy related sectors, electricity generation and transport. Poor decisions will seriously undermine our standard of living.
Let’s look at each of those three questions in turn.
What is clean energy? Most people think of it as renewable energy. Some, particularly in the electricity generation sector, consider gas and “clean” coal to be clean energy. It is true that both gas and clean coal will produce much lower greenhouse gas emissions than black or brown coal. But are they clean enough?
The Treasury doesn’t think so. Not if we want to stabilise greenhouse gases at 450ppm. In its Low Pollution Future Report in 2008, the Treasury indicated that electricity emissions need to be below 50kg per megawatt-hour globally by 2050. Based on current industry estimates, both gas and clean coal will fail this test.
Many forms of renewable energy will pass this test, depending on how they are used. But can they replace fossil fuels?
The simple answer is yes, they can, if they are used with plenty of expensive electricity storage. The tricky part is probably in transport where replacing oil will be a major challenge because of its high energy density. It seems likely that electricity will be the answer for transport either directly (as in light vehicles) or indirectly to artificially produce synthetic fuels for heavy vehicles. The problems to be solved are really all in the electricity sector.
What about the cost?
The most promising and mature renewable energy option for high capacity electricity generation is concentrated solar thermal power with adequate heat storage. It can technically replace both coal and gas - except perhaps over extended days of cloud. The issue is cost.
Recent estimates (PDF 1.55MB) from The Australian Bureau of Agricultural and Resource Economics (ABARE) put the cost of solar thermal at six times the cost of coal. The solar thermal industry believes these costs will fall over time and ABARE has the cost dropping 25 per cent by 2030 so it will only be 4.5 times the cost of coal - admittedly without a price on carbon. A carbon price of $75 will lower the difference to 2.5 times.
These solar thermal costs do not include any additional reserve generation or electricity storage capacity needed to cope with extended, widespread cloud cover when a number of solar thermal plants may need to be taken offline.
We have other promising renewable energy options to replace coal. According to ABARE, hot rocks geothermal could be half the price of solar thermal by 2030 - if we ever get it working. This is anything but mature technology, so delivery and cost are somewhat uncertain but it’s certainly worth keeping in the kitbag.
Other renewable technologies like wind and solar PV are mature but will probably be restricted to a relatively minor role because of the need for expensive storage. Energy efficiency and conservation can also help reduce demand for energy which will assist in the fossil fuel replacement process.
Managing reliability in an electricity network relying on variable renewable technologies will require a much smarter grid and extensive storage. Careful analysis will be needed to ensure sufficient storage is available to handle extreme adverse weather events such as widespread, persistent cloud over solar thermal plants. These will all add to the cost.
So where does that leave us?
We can possibly replace fossil fuels with renewable energy but we will pay a big price to make it work reliably. We could see electricity costs at least quadruple in real terms by 2030 and probably more. If geothermal comes good we might get away with less storage but the cost will at least double by 2030. Do we need to pay this price?
Well no. We have another mature technology which passes the emission test as well as any renewable energy option. Based on a recent analysis of 15 separate studies performed over the last 10 years, this mature technology will do the same job as new coal plants for about the same electricity cost with no future cost increase from a carbon price.
So why aren’t we planning to use this technology? Most of the world already does and has plans to build a lot more plants to replace coal. The technology, of course, is nuclear power. No emissions in operation. Very low fuel cost. High reliability and no significant increase in energy costs. It really does not make any sense for this technology to be ignored in Australia.
Pursuing a 100 per cent renewable energy option (with its inherent risks of failure) to replace fossil fuels could burden our grandchildren with significantly higher energy costs and a flow-on effect to their standard of living. Australia is a low-cost energy country. Why would we want to give up this commercial advantage unnecessarily? I don’t think our grandchildren will thank us for it.
Friday, February 12, 2010
Op-ed Opinion in ABC Environment - 12 Feb 2010
Dash for gas in the wrong direction
Gas and renewables may seem like energy solutions, but nuclear is the only technology to meet our needs and our international obligations.
What did come out of Copenhagen was recognition from developed countries of the need to limit warming to two degrees Celsius. Various emission abatement targets have been bandied about but there seems to be some agreement around a 25% reduction by 2020 and 80% by 2050 for developed countries as a minimum to achieve the two degree limit. What would it take to achieve that in Australia - irrespective of the market mechanism?
Most of our emissions come from the energy sector and the biggest culprit is electricity generation. Emissions abatement in Australia means moving to clean energy and particularly clean electricity. Market mechanisms encourage clean energy but they don't create it. That is a role for technology. So let's look at electricity generating technology with a view to moving to clean electricity.
Ninety percent of electricity emissions come from burning coal. Shut down the coal plants and our clean electricity problem is solved. But we still need the lights to come on, so the first technology challenge is deciding what to replace the coal plants with. Whatever we use must be a reliable source of power.
Electricity is not like water. Storing electricity is possible but expensive so it has to be made in the right quantity at exactly the time we use it. Coal power stations are the engine room of our electricity network. They keep the network running smoothly while hydro and gas plants are turned on and off to handle the changing demand through the day. An unreliable network means disrupting factories, offices, homes and public transport with significant loss in productivity and services.
The "dash for gas" looks like the simple solution. Gas is a ready substitute for coal as far as the electricity network is concerned. Australia is blessed with plenty of gas supply but we might need to cut back on exports. Replacing coal with gas will be expensive and will cost some coal miners their jobs but is eminently doable. TRUenergy already has such a proposal for its brown coal plant in Yallourn in Victoria. But will a dash for gas deliver us the abatement targets we need?
Unfortunately the answer is no.
Two things count against it. First, according to Treasury, our demand for electricity will grow by 7% by 2020 and 38% by 2050. All those extra people will consume more electricity even with substantial improvements in efficiency. Second, gas still produces emissions - about half the emissions of black coal and one third the emissions of brown coal. Even if it were possible to replace all the most-polluting brown coal with gas by 2020 we would still miss the 25% reduction target by a staggering 40%. The 2050 goal is impossible even with all the coal, both brown and black, gone.
So what are the alternatives?
Variable sources like wind and solar panels really need bulk energy storage if they are to replace coal. Hydro systems deliver bulk storage but with Australia's water resources it is not a realistic option in the scale needed. We would probably need to replicate Sydney's entire reservoir system and dedicate it wholly to storage just to cover our current power demand. We can't siphon the water off for drinking. Conservationists oppose new reservoirs and there doesn't seem to be many other attractive bulk storage options with sufficient potential.
Solar with heat storage is a possible option but no one has yet built a round-the-clock solar system without using gas. Geothermal using hot rocks might be an option but it's still under development and not yet a proven technology. Biomass needs hundreds of thousands of hectares of arable land to run just one large power station. All these solutions may have some place in the future but it is difficult to see them replacing all the coal plants.
There is really only one clean energy technology that can reliably and efficiently replace coal plants and deliver the kind of abatement we need to achieve the two degree limit. That is nuclear power.
The type of nuclear plants that are being installed in China and Korea today can do the job. Five 1.5 gigawatt nuclear plants built here over the next 15 years could replace all the brown coal first and reduce emissions by 25% by 2025. A further 27 nuclear plants by 2050 could supply all the power we need for our expanded population and reduce emissions by more than the targeted 80% reduction. Nuclear will actually be cheaper than gas once we have a price on carbon and cheaper than solar thermal.
Britain tried the dash for gas in the 1990s. They also built plenty of wind farms both on and off shore (solar isn't really an option in the UK as anyone - like me - who has lived there will tell you) but they realised gas wasn't going to get them to the abatement targets they needed. They now plan to build 10 more nuclear power plants - something that seems to be off the agenda here - and needs to be put back on!
Monday, December 14, 2009
Op-ed piece in the National Times 14 Dec 2009
Renewable energy is not as reliable as nuclear
Climate scientists have presented us with a huge challenge that demands a massive collaborative effort from engineers and scientists all over the world. The scientists tell us we need to substantially reduce our greenhouse gas emissions. Even if we achieve this, we will still need to adapt to the changing climate.
Fortunately we are now blessed with a wonderful tool ideally suited to such a collaborative task. One that allows us to exchange ideas instantly and hold discussions with anyone, anywhere at minimal cost. It is, of course, the internet.
The internet relies on a very important energy carrier that happens to be the biggest cause of the problem that needs to be solved. That energy carrier (electricity) is the largest single source of all greenhouse gas emissions.
For the internet to work effectively it needs access to reliable electricity available every second of every day. From the computers in our homes and workplaces to the communication systems and internet servers around the world that connect us all together, all need a continuous and uninterrupted electricity supply. Electricity is really the life-blood of our modern technological society.
Two-thirds of the world's electricity comes from "polluting" coal and gas-fired power stations. These generators are the heart of our electricity supply. We need to be very careful that while seeking a solution to the problem of emissions that we don't stop that heart and interrupt the vital blood flow to our internet network. This could damage our capacity to work together on this mammoth problem.
The coal-fired power stations are really like a diseased heart that can pump the life-blood well enough but is poisoning our body with toxins. Closing down these coal plants would stop the toxic greenhouse gases but would also stop the life-blood flowing and kill the necessary tools of technological collaboration that we need to address the problems of climate change.
What we need is a heart transplant that won't kill the patient. Our heart surgeons have a few options available to them. They could replace the coal-heart with a wind-heart or a solar-heart. Both these heart options have reliability and stability issues. The wind-heart produces a variable blood flow and sometimes stops altogether.
Most solar-hearts only works in the daytime and the blood stops flowing at night. There are some solar-hearts on the drawing board that could work all night but no one has built one yet and when they do they will be very expensive.
No competent surgeon would replace a coal-heart with a wind or daytime-only solar-heart without an alternative blood supply. To do so would undoubtedly kill the patient. They were prepared to attempt this operation in Denmark because they had access to an excellent "blood bank" next door in Germany, Norway and Sweden to provide continuous transfusions to stabilise the patient when the transplanted wind-heart gets erratic – which it frequently does.
Alternatively, our surgeons could use a gas-heart. The gas-heart can do the same job as the coal-heart and produce less toxins but the climate scientists believe that even these reduced toxin gas-hearts will still eventually prove fatal. There are other more reliable hearts such as the biomass-heart and the hydro-heart but these transplants will only take in smaller patients like Norway. They won't be big enough to become the heart of Australia's electricity network.
Is spite of the risks, advocates of wind- and solar-hearts want the operation done as quickly as possible — even in Australia where no external "blood bank" exists. They say the technology problems with these hearts will be addressed in time. But if the internet dies in the meantime where will the technology revolution come from?
Maybe the best option open to the surgeons is to use a nuclear-heart. The current production version of the nuclear-heart will do exactly the same job as the existing diseased coal-heart without the carbon toxins. These current nuclear-hearts do produce a small amount of toxic waste, but the doctors think this is manageable and will not kill the patient or even make it sick. After all, they have been doing this operation for more than 50 years around the world and the mortality rate has been miniscule. There is a disadvantage with the current nuclear-heart in that it will probably only last 50-100 years but that will at least reduce greenhouse gases and keep the internet running so the climate problems can be addressed.
The next version of the nuclear-heart, the fast reactor nuclear-heart, is expected to be a available within a few decades. A fast reactor heart will last for thousands of years, leave even less toxic waste and can be regularly upgraded as technology improves. There is even a promise of a nuclear fusion-heart that will outlive the planet.
If you had to have a coal-heart transplant without waiting for new technology – which option would you chose?
Climate scientists have presented us with a huge challenge that demands a massive collaborative effort from engineers and scientists all over the world. The scientists tell us we need to substantially reduce our greenhouse gas emissions. Even if we achieve this, we will still need to adapt to the changing climate.
Fortunately we are now blessed with a wonderful tool ideally suited to such a collaborative task. One that allows us to exchange ideas instantly and hold discussions with anyone, anywhere at minimal cost. It is, of course, the internet.
The internet relies on a very important energy carrier that happens to be the biggest cause of the problem that needs to be solved. That energy carrier (electricity) is the largest single source of all greenhouse gas emissions.
For the internet to work effectively it needs access to reliable electricity available every second of every day. From the computers in our homes and workplaces to the communication systems and internet servers around the world that connect us all together, all need a continuous and uninterrupted electricity supply. Electricity is really the life-blood of our modern technological society.
Two-thirds of the world's electricity comes from "polluting" coal and gas-fired power stations. These generators are the heart of our electricity supply. We need to be very careful that while seeking a solution to the problem of emissions that we don't stop that heart and interrupt the vital blood flow to our internet network. This could damage our capacity to work together on this mammoth problem.
The coal-fired power stations are really like a diseased heart that can pump the life-blood well enough but is poisoning our body with toxins. Closing down these coal plants would stop the toxic greenhouse gases but would also stop the life-blood flowing and kill the necessary tools of technological collaboration that we need to address the problems of climate change.
What we need is a heart transplant that won't kill the patient. Our heart surgeons have a few options available to them. They could replace the coal-heart with a wind-heart or a solar-heart. Both these heart options have reliability and stability issues. The wind-heart produces a variable blood flow and sometimes stops altogether.
Most solar-hearts only works in the daytime and the blood stops flowing at night. There are some solar-hearts on the drawing board that could work all night but no one has built one yet and when they do they will be very expensive.
No competent surgeon would replace a coal-heart with a wind or daytime-only solar-heart without an alternative blood supply. To do so would undoubtedly kill the patient. They were prepared to attempt this operation in Denmark because they had access to an excellent "blood bank" next door in Germany, Norway and Sweden to provide continuous transfusions to stabilise the patient when the transplanted wind-heart gets erratic – which it frequently does.
Alternatively, our surgeons could use a gas-heart. The gas-heart can do the same job as the coal-heart and produce less toxins but the climate scientists believe that even these reduced toxin gas-hearts will still eventually prove fatal. There are other more reliable hearts such as the biomass-heart and the hydro-heart but these transplants will only take in smaller patients like Norway. They won't be big enough to become the heart of Australia's electricity network.
Is spite of the risks, advocates of wind- and solar-hearts want the operation done as quickly as possible — even in Australia where no external "blood bank" exists. They say the technology problems with these hearts will be addressed in time. But if the internet dies in the meantime where will the technology revolution come from?
Maybe the best option open to the surgeons is to use a nuclear-heart. The current production version of the nuclear-heart will do exactly the same job as the existing diseased coal-heart without the carbon toxins. These current nuclear-hearts do produce a small amount of toxic waste, but the doctors think this is manageable and will not kill the patient or even make it sick. After all, they have been doing this operation for more than 50 years around the world and the mortality rate has been miniscule. There is a disadvantage with the current nuclear-heart in that it will probably only last 50-100 years but that will at least reduce greenhouse gases and keep the internet running so the climate problems can be addressed.
The next version of the nuclear-heart, the fast reactor nuclear-heart, is expected to be a available within a few decades. A fast reactor heart will last for thousands of years, leave even less toxic waste and can be regularly upgraded as technology improves. There is even a promise of a nuclear fusion-heart that will outlive the planet.
If you had to have a coal-heart transplant without waiting for new technology – which option would you chose?
Friday, December 4, 2009
Op-ed piece in The Australian 4 Dec 2009 (jointly written with Barry Brook)
Clean future in nuclear power
WE may not be getting an emissions trading scheme any time soon but the climate and energy crises still need fixing with real urgency.
For climate, the issue is excess greenhouse gases from burning fossil fuels. For energy, the crisis is dwindling supplies of those fuels and air pollution from coal combustion.
Replacement energy sources need to be reliable, plentiful and economic to deploy. They need to be low-carbon to minimise global warming. Business-as-usual or half measures risks saddling future generations with a climatically hostile planet and energy scarcity.
Nuclear power is one obvious replacement source, but typically raises five objections.
First, readily available uranium supplies are limited. If the world was wholly powered by present-style nuclear reactors there would be at most a few decades of energy before cheap uranium was exhausted.
Second, nuclear accidents have happened in the past, suggesting this technology is dangerous.
Third, expansion of nuclear power would risk the proliferation of nuclear weapons.
Fourth, we would leave future generations with the legacy of long-lived nuclear waste.
Fifth, large amounts of energy (and possibly greenhouse gases) would be required to mine, mill and enrich uranium and to build and later decommission nuclear power stations.
All the above points have merit, although their relative importance comparedwith climate change and critical energy shortages is debatable. But there is little point in debating these objections because none will apply to future nuclear energy generation.
Almost all today's nuclear power stations are thermal reactors. These use water to slow the neutrons that cause uranium atoms to split (fission) and to carry the heat generated in this reaction to a steam turbine to generate electricity.
Because of the gradual build-up of fission products (neutron poisons) through time, we end up getting less than 1 per cent of the useable energy out of the uranium. The rest is thrown out as that long-lived waste.
In contrast, newer fast reactors are able to use almost all of the energy in uranium. There is enough energy in already mined uranium and stored plutonium from existing stockpiles to supply all the world's power needs for more than three centuries before we need to mine any more uranium.
Fast reactors can be used to burn all existing reserves of plutonium and the nuclear waste from the past and present generation of thermal reactors. With additional uranium mining, there is enough energy in proven deposits to supply the entire world for many thousands of years. This deals with the first objection.
As to the second objection, modern reactors use passive safety systems requiring no operator intervention to shut down the reaction. This makes them safe. So safe that a certification assessment for Westinghouse's AP-1000 reactor put the risk of a core meltdown such as the one that occurred at in the US in 1979 at Three Mile Island at once every 24 million reactor years.
Comparing the flawed Chernobyl design to today's reactors is like saying modern aviation is too dangerous because the Hindenburg airship exploded in 1937.
On the third objection, proliferation, the nuclear fuel used by fast reactors is initially very radioactive, making it impossible to divert to a nuclear weapons program without an expensive, heavily shielded, off-site reprocessing facility that would be readily detected.
In fact, the only nuclear waste materials that will ever leave an Integral Fast Reactor complex (which has on-site recycling) are fission products, which decay to background levels of radiation within a few hundred years.
Unlike conventional nuclear waste, which can last for hundreds of thousands of years (the fourth objection), the waste from IFRs can be more readily stored because of its small volume (150 times less than used nuclear fuel from thermal reactors) and short storage times.
The fifth objection, concerning greenhouse gases generated in building nuclear power plants, has never stood up to detailed life-cycle analysis.
Renewable energy sources (such as wind and solar) use significantly more raw materials per unit of energy generated than even present-generation nuclear power stations and the full life-cycle emissions, including nuclear fuel production, are similar from both sources. When energy storage and fossil-fuel back-up are included, wind and solar emissions are much higher.
A possible sixth objection could be that we don't need nuclear power when we can use renewable energy. This is a valid objection for countries with abundant hydropower, conventional geothermal power or biomass, the only three renewable sources of proven reliable power that can deliver energy 24 hours a day at an acceptable cost. Solar and wind sources, however, still rely heavily on fossil fuels to deliver reliable, continuous energy.
At today's pace of commercial development we won't see many fast nuclear reactors delivering power to the grid before 2020. This will seem too late for some, but at the present pace, non-hydro renewables will only meet 2 per cent of global energy use.
Either option, therefore, requires radically accelerated research, development and deployment if it is to make a difference to climate change and energy supply. What's required is a project of Manhattan-style proportions or the audacity of the moon-shot vision.
Let's be clear. We have the means to fix the climate and energy crises, or at least avert the worst consequences. New generation nuclear power, supported by an expansion of the thermal reactor fleet, is one possible path to success and one that all nations should support. Rationally considering energy planning requires letting go of old-school thinking about exciting new technologies.
Martin Nicholson is the author of Energy in a Changing Climate.
Barry Brook is professor of climate change at the University of Adelaide's Environment Institute.
WE may not be getting an emissions trading scheme any time soon but the climate and energy crises still need fixing with real urgency.
For climate, the issue is excess greenhouse gases from burning fossil fuels. For energy, the crisis is dwindling supplies of those fuels and air pollution from coal combustion.
Replacement energy sources need to be reliable, plentiful and economic to deploy. They need to be low-carbon to minimise global warming. Business-as-usual or half measures risks saddling future generations with a climatically hostile planet and energy scarcity.
Nuclear power is one obvious replacement source, but typically raises five objections.
First, readily available uranium supplies are limited. If the world was wholly powered by present-style nuclear reactors there would be at most a few decades of energy before cheap uranium was exhausted.
Second, nuclear accidents have happened in the past, suggesting this technology is dangerous.
Third, expansion of nuclear power would risk the proliferation of nuclear weapons.
Fourth, we would leave future generations with the legacy of long-lived nuclear waste.
Fifth, large amounts of energy (and possibly greenhouse gases) would be required to mine, mill and enrich uranium and to build and later decommission nuclear power stations.
All the above points have merit, although their relative importance comparedwith climate change and critical energy shortages is debatable. But there is little point in debating these objections because none will apply to future nuclear energy generation.
Almost all today's nuclear power stations are thermal reactors. These use water to slow the neutrons that cause uranium atoms to split (fission) and to carry the heat generated in this reaction to a steam turbine to generate electricity.
Because of the gradual build-up of fission products (neutron poisons) through time, we end up getting less than 1 per cent of the useable energy out of the uranium. The rest is thrown out as that long-lived waste.
In contrast, newer fast reactors are able to use almost all of the energy in uranium. There is enough energy in already mined uranium and stored plutonium from existing stockpiles to supply all the world's power needs for more than three centuries before we need to mine any more uranium.
Fast reactors can be used to burn all existing reserves of plutonium and the nuclear waste from the past and present generation of thermal reactors. With additional uranium mining, there is enough energy in proven deposits to supply the entire world for many thousands of years. This deals with the first objection.
As to the second objection, modern reactors use passive safety systems requiring no operator intervention to shut down the reaction. This makes them safe. So safe that a certification assessment for Westinghouse's AP-1000 reactor put the risk of a core meltdown such as the one that occurred at in the US in 1979 at Three Mile Island at once every 24 million reactor years.
Comparing the flawed Chernobyl design to today's reactors is like saying modern aviation is too dangerous because the Hindenburg airship exploded in 1937.
On the third objection, proliferation, the nuclear fuel used by fast reactors is initially very radioactive, making it impossible to divert to a nuclear weapons program without an expensive, heavily shielded, off-site reprocessing facility that would be readily detected.
In fact, the only nuclear waste materials that will ever leave an Integral Fast Reactor complex (which has on-site recycling) are fission products, which decay to background levels of radiation within a few hundred years.
Unlike conventional nuclear waste, which can last for hundreds of thousands of years (the fourth objection), the waste from IFRs can be more readily stored because of its small volume (150 times less than used nuclear fuel from thermal reactors) and short storage times.
The fifth objection, concerning greenhouse gases generated in building nuclear power plants, has never stood up to detailed life-cycle analysis.
Renewable energy sources (such as wind and solar) use significantly more raw materials per unit of energy generated than even present-generation nuclear power stations and the full life-cycle emissions, including nuclear fuel production, are similar from both sources. When energy storage and fossil-fuel back-up are included, wind and solar emissions are much higher.
A possible sixth objection could be that we don't need nuclear power when we can use renewable energy. This is a valid objection for countries with abundant hydropower, conventional geothermal power or biomass, the only three renewable sources of proven reliable power that can deliver energy 24 hours a day at an acceptable cost. Solar and wind sources, however, still rely heavily on fossil fuels to deliver reliable, continuous energy.
At today's pace of commercial development we won't see many fast nuclear reactors delivering power to the grid before 2020. This will seem too late for some, but at the present pace, non-hydro renewables will only meet 2 per cent of global energy use.
Either option, therefore, requires radically accelerated research, development and deployment if it is to make a difference to climate change and energy supply. What's required is a project of Manhattan-style proportions or the audacity of the moon-shot vision.
Let's be clear. We have the means to fix the climate and energy crises, or at least avert the worst consequences. New generation nuclear power, supported by an expansion of the thermal reactor fleet, is one possible path to success and one that all nations should support. Rationally considering energy planning requires letting go of old-school thinking about exciting new technologies.
Martin Nicholson is the author of Energy in a Changing Climate.
Barry Brook is professor of climate change at the University of Adelaide's Environment Institute.
Wednesday, October 21, 2009
Op-ed piece in Online Opinion 15 Oct 2009
The future of sustainable energy
Much of our energy today comes from three high-energy resources - oil, coal and gas. These resources took millions of years to form. Over the last couple of centuries we’ve been avidly consuming them so it’s reasonable to suppose that one day they will all be gone.
If at all possible, we should be building our future on more sustainable sources. Something that will continue to provide our descendents with the abundant energy that has helped transform the livelihood of human beings throughout the world.
Sustainable energy is one of those vague terms that can mean different things to different people. It is often used as a “green” catch-all for things like energy conservation, energy efficiency and renewable energy, all with a positive environmental overtone.
A more precise (and more useful) definition of sustainable energy is “sources of energy that provide our energy needs today without jeopardising the needs of future generations”.
So how far in the future are we looking?
David MacKay in his book Sustainable Energy - without the hot air considers that 1000 years will about do it. If you consider how technology has changed since the 11th century, then worrying about what our descendants are using for energy in the 31st century is probably futile - as long as we haven’t destroyed the planet in the meantime, of course.
Others such as the non-profit organisation invVEST consider that 100 years ought to be enough. Given that we are still using the energy sources that were used 100 years ago this might be too short a period. If these resources had been exhausted by our forebears by the early 20th century then we would be living in a very different world today. Some, of course, would wish that it were so.
The experts differ on how long coal, oil and gas will last and estimates vary from decades to a few centuries. But it is generally agreed that these fossil fuels will not meet MacKay’s 1000-year test and may fail the 100-year test and so are not considered sustainable. The experts also differ on how long uranium can supply our current generation of nuclear rectors but we will deal with that below.
Renewable energy sources are often considered to be sustainable as they use resources such as water, wind and sunlight that are, to all intents and purposes, inexhaustible. Many will say that these are the only truly sustainable energy sources. As we shall see, that view ignores the 1000-year test as well as some serious technical deficiencies with some renewable energy sources.
First, not all so called renewable sources are themselves sustainable. For example, some biofuels such as ethanol made from food crops like corn are no longer considered sustainable because of the competing need for the land on which the feedstock grows. The Australian Greens consider some biomass such as wood waste from old-growth forests to be unsuitable feedstock because of the risk to the big carbon sinks of old-growth forests. Hydropower relying on water flow from a particular river may also not be sustainable - particularly in Australia
Second, some renewable sources such as wind and solar PV are too variable to meet our continuous power demands unless combined with conventional sources (fossil fuels and nuclear) to fill in the gaps. Others, like solar thermal with sufficient heat storage to produce continuous reliable power, are prohibitively expensive. So without further technology developments, such as huge cost effective, sustainable electricity storage systems, our energy system in Australia
Geothermal energy is said to be promising but MacKay argues that a geothermal mine would be sustainable only if we are taking the energy out of the ground at the same rate as the earth is replacing it. So we might have to treat geothermal heat more like fossil fuels - a resource to be mined until it runs out.
MacKay also seriously questions whether Britain Britain Australia
Are there any other sustainable energy sources on the horizon?
According to the World Nuclear Association, today’s generation of nuclear reactors use an average of 175 tonnes a year of uranium per GW. These reactors are largely using the uranium in a “once-through” cycle where less than 1 per cent of the uranium is actually used to generate energy.
MacKay estimates that the total world recoverable uranium is about 27 million tonnes. This includes resources mineable at less than $130 per kg (the higher-grade resources of around five million tonnes) and lower-grade resources contained in phosphate deposits that will be more expensive to mine. According to the International Energy Agency, because nuclear reactors use relatively little fuel most of the cost in generating nuclear energy is in the planning, construction and decommissioning of the power station not in the fuel. This means that a significant increase in the price of uranium has a much lower impact on the price of electricity. So it is reasonable to suppose that as the cheaper higher-grade resources become depleted the industry will be able to turn to the lower-grade resources.
Using all this recoverable uranium, our current nuclear reactors could operate for 400 years so they would fail the 1000-year test but comfortable satisfy a 100-year test . But the WNA expects the world’s reactor numbers to more than double over the next few years so our current once-through reactors using uranium may not be sustainable depending on your view of sustainability.
Thorium can be used as an alternative to uranium. It is three times as abundant in the earth’s crust as uranium and is more evenly distributed around the world including Australia India
The newer generation fast breeder reactors burn up all the uranium so they can extract much more energy from uranium than traditional once-through reactors. MacKay estimates that fast breeder reactors obtain roughly 60 times as much energy from the same amount of uranium. They can also use all the discarded uranium from existing once-through reactors. This technology is not new either and several experimental reactors have been constructed over the last few decades but the promising Integral Fast Reactor technology might take several decades to become a commercial standard.
Fast breeder nuclear reactors could be the sustainable energy source we are looking for.
To the Greens this will all be bad news. First renewable sources will not deliver reliable, sustainable energy on their own - at least not in Australia
Monday, August 10, 2009
Op-ed piece in On Line Opinion 10 Aug 2009
Can we really replace coal?
“Coal is too cheap.”
That was a quote from a keynote address given a few weeks ago at the Melbourne Festival of Ideas by author Kate Grenville titled On Artists, Writers and Climate Change. [www.abc.net.au/tv/fora/stories/2009/07/09/2621185.htm] The quote was from a retired professor of physics who clearly saw the demise of cheap coal as desirable for addressing climate change. He obviously wasn’t an anthropologist or engineer.
Two centuries ago there were those who fought against mechanisation. Their main concern was jobs (nothing has changed much) but some of the protestors might have argued that steam engines driven by dirty coal were polluting the environment. If only they had understood global warming theory in those early day they might have been able to stop mechanisation in its tracks and we could still be living in peace and harmony tending our farms, not fretting about climate change and enjoying our life expectancy of 38 years.
Cheap coal allowed us to build our modern society. Our wealth, health, standard of living, education and longevity we owe to coal through mechanisation and abundant, round-the-clock electricity. These are now essential components of our modern society and energy security is high on any government’s agenda. Some may rue the day the steam engine was invented but not many of us.
But could we replace coal and keep our modern society?
Coal has not been easy to replace over the centuries and it may still be with us for many decades to come. Despite what conservationists think, this has not been because of political inactivity or an aggressive coal lobby but lack of technology and suitable alternative energy sources.
Over a century ago, oil replaced coal for road transport. In theory it could replace coal for electricity. All you need is a machine to drive a generator so any suitable fuel will do as long as it is available when you need it. And there’s the rub. With some claiming peak oil has already passed we need the rest of the oil for transport and industry.
Gas could replace coal but not everywhere. It probably could in Australia where we have abundant gas supplies (although less than coal) but gas certainly isn’t as cheap as coal so we will pay a price. Many countries would have to import the gas while they sit on coal reserves and this may be inconsistent with their government’s need for energy security.
Nuclear power can certainly replace coal for electricity anywhere and with significantly lower greenhouse gas emissions. It already does in many countries, but not in Australia. Now that is due to political inactivity and is neither a technology problem nor a local resource availability issue.
What about renewable energy?
As I said before, all you need is a suitable fuel (or energy resource) to make electricity. With round-the-clock electricity, the trick is having the fuel when you need it. Ample theoretical resources are not enough – the actual supply needs to be nearly constant and above all reliable. If the energy resource is the wind, the sun, moving water, heat from the ground or even wood waste, this is a problem to differing degrees. Wind and sun are the worst with highly variable supply. Wood waste supply can be constant but depends on the availability of land to grow enough wood.
Some countries are blessed with ample supplies of constantly available and reliable moving water or supplies of underground heat but not many. Even Australia struggles with hydropower from time to time.
Technologies are being developed like man-made geothermal systems and solar thermal electricity with adequate heat storage that could maintain a constant and reliable supply of electricity but it may take some time before they are ready to replace significant quantities of coal.
The beauty of coal, gas and uranium is that the fuel can be readily stored in its usable form for when we need it, unlike the wind or sunlight. If we could store the electricity produced from the wind and the sun when it’s available for later use then the variable supply would be less of a problem. The difficulty is that electricity can only be stored in any quantity as another form of energy (such as chemical or kinetic energy) and this is expensive. We seem a long way from achieving adequate quantities of cost effective electricity storage.
The idea of renewable energy powering our electricity networks alone anytime soon is a fantasy for the vast majority of the world. Most people in western society don’t want to return to a 19th century lifestyle when electricity was expensive and not always available while they wait for the right technologies to be developed. Getting rid of reliable electricity would probably fix that mechanisation problem that the luddites fought so hard against all those years ago. I doubt it will save many jobs though.
If a country doesn’t have adequate gas or is not prepared to use nuclear power then coal is the only realistic option for electricity generation until technology catches up. So thank goodness coal is cheap – and still abundant.
“Coal is too cheap.”
That was a quote from a keynote address given a few weeks ago at the Melbourne Festival of Ideas by author Kate Grenville titled On Artists, Writers and Climate Change. [www.abc.net.au/tv/fora/stories/2009/07/09/2621185.htm] The quote was from a retired professor of physics who clearly saw the demise of cheap coal as desirable for addressing climate change. He obviously wasn’t an anthropologist or engineer.
Two centuries ago there were those who fought against mechanisation. Their main concern was jobs (nothing has changed much) but some of the protestors might have argued that steam engines driven by dirty coal were polluting the environment. If only they had understood global warming theory in those early day they might have been able to stop mechanisation in its tracks and we could still be living in peace and harmony tending our farms, not fretting about climate change and enjoying our life expectancy of 38 years.
Cheap coal allowed us to build our modern society. Our wealth, health, standard of living, education and longevity we owe to coal through mechanisation and abundant, round-the-clock electricity. These are now essential components of our modern society and energy security is high on any government’s agenda. Some may rue the day the steam engine was invented but not many of us.
But could we replace coal and keep our modern society?
Coal has not been easy to replace over the centuries and it may still be with us for many decades to come. Despite what conservationists think, this has not been because of political inactivity or an aggressive coal lobby but lack of technology and suitable alternative energy sources.
Over a century ago, oil replaced coal for road transport. In theory it could replace coal for electricity. All you need is a machine to drive a generator so any suitable fuel will do as long as it is available when you need it. And there’s the rub. With some claiming peak oil has already passed we need the rest of the oil for transport and industry.
Gas could replace coal but not everywhere. It probably could in Australia where we have abundant gas supplies (although less than coal) but gas certainly isn’t as cheap as coal so we will pay a price. Many countries would have to import the gas while they sit on coal reserves and this may be inconsistent with their government’s need for energy security.
Nuclear power can certainly replace coal for electricity anywhere and with significantly lower greenhouse gas emissions. It already does in many countries, but not in Australia. Now that is due to political inactivity and is neither a technology problem nor a local resource availability issue.
What about renewable energy?
As I said before, all you need is a suitable fuel (or energy resource) to make electricity. With round-the-clock electricity, the trick is having the fuel when you need it. Ample theoretical resources are not enough – the actual supply needs to be nearly constant and above all reliable. If the energy resource is the wind, the sun, moving water, heat from the ground or even wood waste, this is a problem to differing degrees. Wind and sun are the worst with highly variable supply. Wood waste supply can be constant but depends on the availability of land to grow enough wood.
Some countries are blessed with ample supplies of constantly available and reliable moving water or supplies of underground heat but not many. Even Australia struggles with hydropower from time to time.
Technologies are being developed like man-made geothermal systems and solar thermal electricity with adequate heat storage that could maintain a constant and reliable supply of electricity but it may take some time before they are ready to replace significant quantities of coal.
The beauty of coal, gas and uranium is that the fuel can be readily stored in its usable form for when we need it, unlike the wind or sunlight. If we could store the electricity produced from the wind and the sun when it’s available for later use then the variable supply would be less of a problem. The difficulty is that electricity can only be stored in any quantity as another form of energy (such as chemical or kinetic energy) and this is expensive. We seem a long way from achieving adequate quantities of cost effective electricity storage.
The idea of renewable energy powering our electricity networks alone anytime soon is a fantasy for the vast majority of the world. Most people in western society don’t want to return to a 19th century lifestyle when electricity was expensive and not always available while they wait for the right technologies to be developed. Getting rid of reliable electricity would probably fix that mechanisation problem that the luddites fought so hard against all those years ago. I doubt it will save many jobs though.
If a country doesn’t have adequate gas or is not prepared to use nuclear power then coal is the only realistic option for electricity generation until technology catches up. So thank goodness coal is cheap – and still abundant.
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