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?

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.

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 11^th century, then worrying about what our descendants are using for energy in the 31^st 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 20^th 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. Climate change may dry up rivers or change their course and leave the hydro system stranded.

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 is not sustainable today with or without renewables. See Hasten slowly into renewable energy.
 

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 could ever generate enough energy from renewable resources to meet its energy needs even if technology was not an issue. Britain (and possibly Australia) may have to look at other options to find sustainable energy.

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. Thorium has the added advantage that, unlike uranium, it can be completely burned up in simple reactors so it creates less long-lived radioactive waste. India already uses thorium in nuclear reactors so the technology is not new, but it will still not be sustainable using current generation reactors.

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. But worse news for the Greens is that the most likely source of sustainable energy will actually be nuclear power. James Lovelock knew this all along of course.

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.

Op-ed piece published in On Line Opinion 26 June 2009

Hasten slowly into renewable energy

For more than 200 years, modern society has been built on the back of cheap energy taken from the ground. That energy has been used to deliver improved life expectancy, better health care, personal mobility, intellectual opportunity, universal access to information and egalitarianism. In the meantime, and perhaps because of it, we have become dependent on motor vehicles and round-the-clock electricity.

It took the Earth millions of years to develop those stores of high energy density fossil fuels (coal, oil and gas). In the last 150 years, big holes have been made in those fuel stores. For oil, at least, production may soon peak and start to fall. Gas may be in short supply this century and, eventually, coal will meet the same fate. All this at a time of growing energy demand from countries like China and India.

As if this were not concern enough, we are now told that these high carbon fuels are damaging the atmosphere and warming the planet and we need to quickly replace them with other forms of energy. Further, to avoid the same problem happening again, we need these energy sources to be low-carbon and sustainable. This is a Herculean task. We are trying to do in a few decades what the earth took millions of years to do.

All energy sources come from the sun, directly or indirectly. Before man started digging huge quantities of coal out of the ground, energy use was largely sustainable. Populations were much smaller and people burned wood and peat for heating and cooking and there was no mass production. There was some mechanisation in the form of windmills and water wheels and animals or humans to pull ploughs and carts but all these devices sourced their energy indirectly from the sun.

Renewables - wind, moving water, geothermal hot water, solar heating and biomass (burning woody material) - have been sources of energy for millennia. Now we need to leave our fossil fuels behind and go back to renewable energy - from renewables to renewables in 15 generations.

Motor vehicles provide challenges when it comes to sustainable energy. Biofuels (like ethanol and biodiesel) made from plants, are renewable energy that can power motor vehicles. Currently, biofuels provide 1 per cent of all transport fuels and use 1 per cent of all the available arable land worldwide. Even at this relatively low level, they are already blamed for food shortages and are generally recognised as not sustainable.

Hydrogen is another renewable energy that can be used in vehicles but it must be made from low-carbon electricity if it is to reduce greenhouse gas emissions.

A third alternative is electric cars. Whether the vehicles are powered by hydrogen from electricity or electricity directly, replacing oil for transport will significantly increase the demand for electricity. The average family with two cars recharged at home will increase their electricity use by 50 per cent.

Renewable electricity is key to a sustainable energy future. Innovations have proceeded over the last 150 years. In the 19th century, electricity was generated from wind and moving water (hydropower). Electricity from natural geothermal steam was first generated in the early 20th century. In the early 1950s, the photovoltaic (PV) solar cell was developed to generate electricity directly from sun light. Engineered geothermal systems (EGS), sometimes called hot dry rocks, were developed in the 1970s and electricity from concentrated solar power (CSP) using solar thermal energy began commercial generation in the 1980s. Electrical energy has also been harnessed from tides.

These renewable energy sources all have natural cycles varying from decades (geothermal) to seasons (hydropower, biomass) to daily (wind, solar thermal) to hours and minutes (wind, solar PV). Some of these cycles are more predictable than others. We can have a reasonable level of confidence when a dam will have sufficient water to produce hydroelectricity but we cannot be so confident about when the wind will be blowing. This variability makes them less than ideal for every day, round-the-clock electricity supply. The Earth’s fossil fuels provide a huge store of energy that is continuously available and, apart from the occasional power plant breakdown, we can be confident about the amount of electricity we can generate at any one time. Until the fuel runs out of course.

Electricity cannot easily be stored in large quantities. This means it has to be generated at the same time as it’s used. Mass production has led to 24 hours a day factories that demand large quantities of electricity continuously. We want to turn on the lights or watch TV anytime of day or night. This means that the electricity supply companies have to generate electricity at a certain level, 24 hours a day. In Australia, the minimum supply needed round-the-clock (sometimes referred to as baseload) is about two thirds of the total electricity demand.

How are we to supply this round-the-clock demand using renewable sources that have natural cycles that, in most cases, preclude continuous supply?

This situation is not quite as bleak as it seems. As the sources have different cycles, when one is unavailable another may be available. For example, solar power will not work at night but the wind may be blowing. By using a broad mix of renewable technologies we can reduce the variability problem. Although the wind does not always blow strongly in one location it may be blowing somewhere else. By distributing the wind turbines over a wide geographic area we can smooth out the variations in supply from each turbine. But we can never eliminate the problem completely.

The existing electricity networks in Australia have been designed to handle a relative small number of large coal fired generators, mainly located near the coal mines, with some dispersed gas plants all connected by a large grid on the eastern and southern seaboards and a separate grid in the west. Renewable generators like wind farms will generally produce much less power than a coal plant and be more widely distributed and, as discussed, not always available when needed. This means costly upgrades to the existing electricity infrastructure to interconnect and manage all these disparate, smaller renewable energy generators to improve the chance of getting a continuous, uninterrupted supply of renewable electricity everywhere.

Australia’s renewable energy will largely rely on wind and solar power in the short term with some existing hydropower. Even distributing the renewable generators and investing in a more sophisticated electricity network system will not provide the current level of availability of supply that we have grown to expect. With fossil fuels, we are protected against the occasional power station shutdown due to maintenance or unexpected problem by having spare capacity in the network. We can have spare capacity in a renewable network but solar power never works at night and works poorly in very cloudy conditions and wide area wind calms could incapacitate a significant part of the wind supply so our protection against blackouts is substantially reduced.

So how do we deal with this problem if we need to shut down the fossil fuel generators?

We need either gigawatt scale electricity storage or non-renewable reserve capacity. The only proven technology for gigawatt electricity storage is pumped storage where surplus electricity is used to pump water from a large lower reservoir to a higher reservoir. When there is an electricity shortage, the water can be released back into the lower reservoir through a hydroelectric plant. Given Australia’s water supply problems, it seems unlikely that we will build more hydro dams or new large pumped storage systems.

The CSP industry is working on ways to achieve the same thing by storing surplus heat to generate electricity during the night or cloudy days. So far only small plants with eight hours of storage have been demonstrated. Both the wind and the CSP industry recognise that they need fossil fuel reserve capacity (preferably gas) to reliably produce baseload electricity. Even with distributed wind farms, the reserve gas capacity may need to be as much as 25 per cent of the power output of the wind farms.

Any transition to renewable electricity will require the continued use of fossil fuels for some time. Technology improvement to renewable energy continues, so the longer the transition takes, the better the outcome for electricity generation if not the environment.

For example, hot dry rocks - where water is pumped into hot underground granite and the steam brought to the surface to produce electricity - is still in the development phase with demonstration plants being built in Australia. It may take a further two decades to bring this technology to maturity but it has the big advantage of low variability (in the order of decades as the hot rocks cool down) and doesn’t need electricity storage or fossil fuel backup. It has relatively low land use and environmental impact and could save thousands of wind turbines, CSP mirrors and gas reserve plants. Unfortunately, the hot rocks tend to be in regions well away from the electricity demand (like the Cooper Basin) so extensions are still needed to the grid.

Hasten slowly into renewable energy. The technology has a long way to go and there are other ways of reducing greenhouse gas emissions from electricity generation such as carbon capture and storage and nuclear power. Neither of these technologies are ideal but they could buy us time to get sustainable energy right.

Op-ed piece printed in The Australian 6 May 2009

Chancy winds of change

NOW that the Council of Australian Governments has agreed the design of the expanded national renewable energy target scheme to get 20 per cent of Australia's electricity supply from renewables by 2020, perhaps it is time to look at where this renewable electricity may come from and what effect that could have on our electricity supply and greenhouse gas emissions.

The scheme focuses on reaching the 20 per cent target at least cost. According to Department of Climate Change consultants McLennan, Magasanik Associates, the lowest cost renewable energy sources a megawatt hour are hydro, biomass, geothermal hot dry rocks and wind power. Leaving aside hydro (remember water shortages?), MMA saw biomass, HDR and wind as the main contributors to the 20 per cent target.

Biomass electricity is a mature technology but constrained by resources. We already get some electricity from biomass, mainly from bagasse, and MMA expects a 10-fold increase in biomass electricity by 2020.

HDR is emerging technology with enormous potential but there are still no HDR generators in operation in Australia. MMA is not expecting a significant contribution from geothermal before 2015. Given the recent incident at Geodynamics Habanero 3 well site, that date may be further delayed.

The largest contributor to the target is from wind. According to MMA, about a third of the 20 per cent will be from wind, a seven-fold increase over the existing installed wind power.

In case anyone is wondering, MMA doesn't seem to have a great deal of confidence that solar power will make a significant contribution to the 20 per cent, probably because of its high cost. Remember that the RET scheme focuses on the least cost solutions. It seems unlikely solar electricity will be competing with wind any time soon.

The RET legislation will come with a big stick for those electricity retailers and large wholesale electricity purchasers that fail to meet their annual renewable energy targets. This will probably guarantee that much of the 20 per cent does get built. But what will get built and what are the implications? What we do know is that it will be the solutions that appear the lowest cost.

With the HDR wobbles, the resource constraint on biomass and the high cost of solar, the odds are it will be more wind power. Unfortunately, of the three main contenders wind is the most difficult to manage in the electricity network. It is variable and the least predictable energy source of the three. If the wind stops blowing we need to get the power from elsewhere.

Unlike countries in Europe, Australia is isolated so we can't buy power from our neighbours when we need it. If the weather turns calm in countries such as Denmark and Spain (that get a much higher proportion of their electricity from wind power than the RET may deliver) they have ready access to nuclear and coal-generated power from France and Germany. Australia has to be self-sufficient.

If it turns out that half or most of the 20 per cent target has to come from wind power, that will mean greater upgrading of grids and more fossil-fuel reserve generation capacity to cover for any drop in the wind. Apart from making wind power more expensive (and perhaps no longer the lowest cost), it may affect greenhouse gas reductions because reserve fossil-fuel generators will probably have to be kept running and producing greenhouse gases just in case the wind drops unexpectedly. Wind power may not actually replace very much fossil fuel generation.

The danger is that, in the haste to meet our RET targets, the wind power is built before the network is ready. NEMMCO, the electricity system operator, needs to maintain a high reliability standard and accurately match our demand for electricity with supply. The operator may be forced to curtail some of the available wind power to maintain the supply-demand balance. Degrading the wind power output could mean we have built the renewable capacity but are unable to meet the targets.

None of this concerned the NSW Government when it recently streamlined the approval process for new smaller wind farms giving them critical infrastructure status.

Governments are fond of setting specific targets by specific time frames to be seen to be doing something without properly considering the technical feasibility. Geothermal isn't ready for 2020. Hydro and biomass growth is limited by available resources. Solar, tidal and wave power are considered too expensive today and probably still will be in 2020.

Which leaves us with wind and that will probably not deliver as much greenhouse gas reduction as we might have expected unless we are prepared to sacrifice network reliability.

More Melbourne and Sydney blackouts anyone?

Martin Nicholson is the author of Energy in a Changing Climate.

Web Site

I now have a website at energyinachangingclimage.info

Just click on the Web Site heading above


I will be keeping that up to date with the latest developments

Book Launch in Byron Bay

Thanks everyone who came to the book launch in Byron Bay. I hope you enjoyed the food and wine and talking about the book.

Op-ed piece printed in The Australian 29 January 2009

THERE may be some cause for alarm for those who are looking for big cuts in carbon emissions by 2020.

The results of a recent Australian study lead to a worrying conclusion that spending a huge $65 billion on low-emission power-generation technologies will give an 8 per cent rise in emissions from electricity generation by 2020, not the 5 per cent reduction that the Government wants. No cuts in power emissions will make it very difficult to make big cuts in total emissions by 2020, as electricity generation contributes almost 40 per cent of emissions.
The Australian Academy of Technological Sciences and Engineering, a group of scientists and engineers that promotes the development of new and existing technology, has turned its collective mind to the future of electricity generation. In particular, it has considered how the government's projected reductions in carbon emissions might be achieved. This analysis of a range of electricity generation scenarios has been released in an important study, Energy Technology for Climate Change - Accelerating the Technology Response.
The key finding of the report is a need for government and industry to invest about $6 billion by 2020 on research, development and demonstration of new power generation technologies. Installing the technologies by 2050 would need capital investment of about $250 billion.
ATSE considered a scenario for electricity generation in 2020 that uses 20 per cent low-carbon technologies. This scenario is hypothetical (not a prediction) but takes into account an assessment of the state of the technologies. The low-carbon technologies include biomass, solar, wind, wave, geothermal and carbon capture and storage with a balanced split between them. The installation cost of these technologies, including some additional gas generation, is $65 billion over the next 12 years, an average of more than $5 billion ayear.
The net effect of this investment is to increase carbon emissions by 8 per cent from 2000 levels. This is a considerable improvement on the 31 per cent increase that would happen with business-as-usual but the result is of great concern when our government wants to reduce total emissions by at least 5 per cent, and an even greater concern for those that want the reduction to be more like 25 per cent.
Maybe the academy was too conservative with its 20 per cent low-carbon technologies? Hardly. The scenario requires an increase in wind power of more than 1200 per cent in 12 years and an increase from practically zero solar to 6 per cent of total electricity supply over the same period. It also includes a big contribution from the yet to be commercially proven technologies such as wave and geothermal. Gas-generated power would also need to increase (by 40 per cent) and coal-CCS would need to be in production in three large power stations.
Maybe they didn't include savings from energy efficiency? The scenario expects a 20 per cent increase in energy demand by 2020. During the same period the Australian Bureau of Statistics also expects the population to increase by 20 per cent, so possibly the expected scenario includes no net efficiency savings or demand reduction.
Could a reduction in electricity demand fix the problem? Based on the scenario modelling, reducing the demand growth rate from 1.4 per cent per year to 0.8 per cent a year will reduce emissions growth to zero. On past history of trying to generate demand reduction this may be a tall order and zero growth in emissions isn't what we are looking for.
So where do we go from here?
We need to get a quick breakthrough in low-carbon technology (probably not likely to be quick enough), increase the 20 per cent low-carbon target (this target is already looking like a stretch, and is very expensive) or significantly reduce electricity demand further if we have any hope of getting even the "soft" reduction of 5 per cent by 2020. The challenge will be to do all that without greatly affecting the economy and society.
An alternative would be to recognise that even a 5 per cent reduction in electricity generation emissions is not going to happen by 2020. In the meantime, as the academy recommends, we should spend a significant amount more on low-carbon technology research. And maybe start to plan that first nuclear power station.

Martin Nicholson is the author of Energy in a Changing Climate.