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Australia's Transition to Renewable Energy

Posted on 19 September 2017 by Riduna

Australia’s Prime Minister, Malcolm Turnbull rightly points to the need for reliable, affordable electricity supply. He knows that 75% of Australia’s existing coal-fired power stations have passed their design date, increasingly pollute the atmosphere and operate inefficiently. In early 2017 he argued that since Australia is the worlds largest coal exporter, they should be replaced with ultra-supercritical coal fired generators. Recognising that ultra-supercritical generators are very expensive to build, he hinted that the cost of their construction might be subsidised by the Clean Energy Finance Corporation, a government agency funded to promote clean energy rather than coal use.

The Energy Minister, Josh Frydenburg went further, claiming that ultra-supercritical generators would reduce greenhouse gas emissions by as much as 40% and with carbon capture and storage (CCS) technology, carbon emissions could be reduced by about 90%. He went on to repeat his assertion that uncertainty of supply and high cost of electricity in South Australia, was the product of a too rapid transition to renewable power generation.

More recently, AEMO warned that S.A. and Victoria could experience black-outs over the next 2 years and that closure of Liddell Power Station in 2022 could result in a potential shortfall of electricity supply in NSW.   The response from Turnbull was to repeat criticism of Labor State Governments for over-rapid transition to renewable energy, their failure to provide adequate storage back-up and to call for Liddell to be refurbished and kept open for 5 years beyond its intended closure date.


The first comment to make on these observations is to deplore that the imperative of reducing greenhouse gas emissions should made a political football. It is high time that Australia’s major political parties got together to formulate an effective science-based national policy on curbing greenhouse gas emissions and the inevitable transition from fossil fuels to renewable energy. The need for this transition, worldwide, needs to be both rapid and orderly since it is very likely to mediate our ability to survive on this planet.


Fig 1. One of 22 electricity pylons in the North Midlands of S.A., destroyed by an extreme wind event in September, 2016, causing a state-wide blackout. Photo: ABC News: Tom Fedorowytsch.

In Australia, the effects of global warming are already being felt in the form of an increase in the incidence, severity and duration of heat-waves, droughts, bushfires and wind events.   Each of these events reverses ability of the planet to absorb CO2 and causes additional CO2 to enter and remain in the atmosphere. Bushfires and drought kill vegetation, releasing their stored CO2 in the process and leaving less vegetation to absorb on-going carbon released due to human activity. As oceans warm, their capacity to absorb additional CO2 falls, further accelerating global warming.

Secondly, it is necessary to point out the fallacy of arguments put forward to justify future use of so called ‘clean coal’ fired ultra-supercritical power stations as the best means of ensuring emissions reduction and continuity of affordable electricity supply. This is not the best alternative for the following reasons:

1.  Capital cost: Ultra-supercritical power stations cost $1.5 - $3.5 billion to design and build. Investors will compare this cost with the outlay required to build clean energy power station of similar capacity and conclude that wind or solar farms can be built for a fraction of the cost of an ultra-supercritical power station and yield a much better return on capital.

2.  Operating Cost: No matter how efficiently an ultra-supercritical power station operates, it can not compete with a wind or solar farm which have almost no operating costs because they obtain their fuel free and employ very few staff– no more than are needed for cleaning and maintenance.

3.  Build time: An ultra-supercritical power station takes up to 6-7 years to build, compared with a wind/solar farm which can usually be built and commissioned in less than 12 months.

4.  Power cost: Because ultra-supercritical generators incur much higher capital and operating costs their output must be sold at a much higher price than electricity generated from renewable energy, imposing higher energy costs on consumers.

5.  Pollution: Although ultra-supercritical power stations produce around 30% less emissions than older coal fired power stations, they still emit very significant quantities of CO2 (causing global warming) and particulates (damaging health).

6.  Emissions: Carbon capture and storage technology has been trialled at coal fired power stations and found to be so expensive to operate that it almost triples the cost of electricity generated, making it prohibitively expensive for consumers.

7.  Gas: Gas fired power stations produce less pollution than ultra supercritical coal fired power stations and, importantly, are more versatile since they can be brought on/taken off line far more rapidly than coal fired power stations. Rapid increase in generation is essential to cover periods of sudden peak demand.

8.  Investors in the energy sector are aware that a surge in demand for fossil fuels leads to an increase in price but with clean energy technology, a surge in demand results in falling price and more efficient production, making renewable generation a more attractive investment.

There is no substance to the claims made by Turnbull and Friedenburg that ultra supercritical coal fired power stations are essential to assure continuity of supply or that they can generate electricity more cheaply than other forms of generation. While coal fired power stations can – and do - assure continuity of supply it is simply not possible for them to generate electricity cheaper than wind or solar farms which are far cheaper to build, have very low staffing levels and operate on fuel which is free.


Australia needs to maintain back-up generating capacity in order to ensure continuity of electricity supply and stability of the National Grid in the event that any of the following occur:

  • Any of its aging coal fired power stations breaks down or becomes uneconomic to operate and is closed permanently
  • A break in the National Grid caused by severe climate events which are now expected to increase in severity and frequency
  • Damage to renewable energy generators, which could be vulnerable to worsening severe climate event
  • Sudden, short term increase in demand for electricity due to periodic, short-term heat waves

At present, most back-up covering these contingencies is provided by coal fired power stations. However coal fired electricity generation can not provide back-up to maintain National Grid stability since it can not be brought on line, or taken off, at short notice to deal with spikes in demand or damage to the grid. Only battery storage, hydro and to a lesser extent gas fired generation can provide very short term response to a sudden need for additional energy.

When it comes to ensuring continuity of electricity supply Australia has a choice: It can build new coal fired power stations which will be uncompetitive by the time they are operational, or it can increase generation from solar and wind farms which are likely to be equipped with storage within 3 years. The Turnbull government has indicated a strong preference for new coal fired power stations – ultra supercritical power stations equipped with carbon capture and storage, producing lower emissions and assuring continuity of electricity supply – but not for the next 5-7 years.  So, will Australia face power shortages until 2025?


Fig. 2. Hazelwood power station burned brown coal (Lignite) which emitted the equivalent of 1,400 tonnes of carbon dioxide per gigawatt hour of energy produced. Photo: AAP-Greenpeace

Closure of the Hazelwood power station, the ‘dirtiest’ emitter in Australia, with loss of its 1,600 MW capacity, places greater demand on other power stations with surplus capacity.   This will reduce their capacity to deal with other power station closure or periods of peak demand – eg. during heat-waves or to provide back-up for renewable generators.

This difficulty would be exacerbated by future power station closures, possibly those at Liddell NSW, Yallourn W VIC, and Gladstone QLD. All are over 40 years old and have generating capacity of over 5,000 MW.

The alternative, seemingly rejected by the Turnbull Government is to attract investment in new solar and wind farms. Both can be built rapidly, generate cheaper electricity and are likely to have ability to provide power 24/7, possibly in less than 3 years as more efficient, higher capacity domestic and utility-scale battery storage becomes available.

For all of the reason outlined above, government has been unable to find a willing investor in ultra supercritical power houses – even when public funding for such a venture is mooted.


A solution to Australia’s so-called electricity supply crisis is to encourage investment in developing electricity storage capacity – a point on which there is common agreement among politicians. Pumped hydro involves using off-peak coal fired or renewable electricity to pump water into a high dam, release it for electricity generation when required, then pump it back into a high dam using solar energy. It offers the largest most rapid back-up storage facility - up to 500 MW over a 5 hour period. Two new pumped hydro projects which have attracted ARENA support are at Kidston, Qld and at Spencer Gulf, SA, projects expected to take 3 years to develop.


Fig 3. Solar Concentrators supply electricity 24/7 by storing heat used to generate dispatchable electricity for up to 8 hours when the sun is not shining.  Photo: Ecogeneration.

The South Australian government has already planned for construction of a rapid response gas-fired power station expected to be operational within a year. It has ordered construction of the worlds largest lithium-ion battery providing 129 MWh to be completed in late 2017 and has encouraged diversified investment in renewable energy storage. The latter has resulted in approval of the worlds largest (135 MW) solar thermal plant being built near Port Augusta and scheduled to be operational in 2020.

The Queensland Government is financing transmission lines for the Kidston pumped hydro scheme generating 783 GWh/annum. Construction of Stage 1 of 2 is in progress and expected to complete in 2018. The government also intends to re-commission its Swanbank power station, converting it to gas fired and able to provide rapid response back-up when required.

Timely back-up is being provided and before 2022 it is likely that advances in battery technology will have enabled tripling of existing battery storage capacity at reduced cost. So, the position is not as dire as some would have us believe.

An increase of surplus generating capacity is already being achieved by residential take-up of solar panels by more than 1.5 million households with capacity to reduce demand on the grid by over 5 gigawatts. Up-take of solar panels is on-going and will accelerate as the price of domestic battery storage continues to fall, further reducing household consumption of electricity from the grid. Some State Governments are encouraging households to install battery storage since these batteries can be a source of energy required to maintain grid stability.

Utility scale storage other than that noted above is essential. It already exists but is expensive and has limited capacity, though cost is falling rapidly and capacity, presently limited to ~100MW, is increasing. Some technologies now being trialed and soon to be commercialised claim scalable storage capacity of 200 MW which, if demonstrated, could revolutionise grid management possibly enabling intermittent solar and wind farms to become the equivalent of base load generators.

It is open to Government to take-up mitigating measures, which reduce normal demand and to encourage households and businesses to do the same. Most governments and publicly owned enterprises in Australia have failed to do this, even though this measure could permanently and significantly reduce demand for electricity and increase availability of surplus capacity to cope with most increases in demand.

It is likely that within the next 10 years many – possibly most - of Australia’s coal fired power stations could close because of their age and inability to compete with renewable electricity generators. Ad interim, it is the responsibility of State governments to ensure that they are replaced with renewable energy generators in an orderly and timely way and that sufficient storage capacity is available to provide back-up for renewable generators.

Reforms in regulation and operation of the national grid during the transition from coal to renewable energy sources are overdue and should aim to increase competition, lower electricity costs and ease the transition to renewable energy. As indicated above, this transition is already underway and from commercial and environmental perspectives is not reversible.

Prime Minister Turnbull and his Energy Minister should ask themselves how California (the 6th largest economy in the world), Denmark, Germany and other countries have no problem in managing Grid stability when around 50% of their electricity already comes from renewable sources?

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Comments 1 to 8:

  1. There seems a lack of a master plan here. They appear to be making it up as they go along. I appreciate its partly politics, but its chaotic and a bit scary.

    Say for example if Australia has total reliance on a mix of solar and wind (which seems the sensible thing given their climate) then you will need "x" quantity of gas fired backup, or alternaively "y" quantity of surplus solar and wind as a backup, or alternatively "z" quantity of storage. Or some combination of these. Surely someone has some sort of master plan and calculations? I would be interested if anyone knows and can point me at specific information.

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  2. There's no bloody master plan in New Zealand either.  Is there anybody with a master plan?

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  3. I find it very disturbing that super-critical coal plants have been renamed as "low emissions" - and much of the media in Australia have gone on to take up that deceptively misleading terminology without objection. Worse is that the definitions of "low emissions" under which support for emissions reductions are based are under threat of being rewritten by an openly pro-fossil fuels government to include such coal generation. Generation that in no respect is actually low emissions.

    The Orwellian doublespeak in Australian public discourse is getting so commonplace that it actually appears to be successfully changing the fundamentals of the debate away from climate responsibility; energy policy is about cost and reliablity and on the rare occaisions gov't spokespeople mention emissions reductions at all it is in ways that imply those are entirely about kowtowing to international agreements, not about achieving climate stability.

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  4. Queensland, Victoria and South Australia do have plans for transition to renewable energy generation which involve provision if targets, provision of back-up (diesel generators, gas fired peaker stations) and energy storage (pumped hydro, batteries). Oz has over 20,000 sites suitable for pumped hydro with pumping powered by solar or off-peak existing coal-fired.

    The Federal Government also has a plan, based on building additional coal-fired power stations and Snowy Scheme pumped Hydro. By the time these measures become operational, in 5-7 years time, battery and solar technology will have advanced to make coal fired power generation uncompetitive with renewables and overcoming present capacity limitations on electricity storage.

    Recent calls by the National Party and right wing Liberals for all subsidies for renewables to be withdrawn, simply adds to investment uncertainty – a problem which State governments are overcoming by supporting the best renewable energy proposals. It’s a shame the Feds are so ideologically committed to coal. However, market forces will ensure a renewable future.

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  5. Ken, well I realize it is PR, but the super-critical plants do have lower emissions per kWh of electricity produced than subcritical plants. If you are going to build a coal plant anyway, then I much prefer it is USC than convential cycle. Of course, it might be good to ask some hard questions about whether they are working as designed and what the actual heat rate from the plants are.

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  6. Given the high capital and recurrent costs of a USC power plant, how will it be able to generate electricity at a price which (a) does not put upwards pressure on the price of electricity and (b) how will it contribute to meeting our (modest/inadeqwuate) obligations under he Paris Accord by redcing our CO2 emissions?  A USC power plant may result in (30%?) lower emissions but solar/wind generators result in 100% lower esmissions.

    What investor in his right mind would invest in a hugely expensive USC power plant when far greater 'bang for the buck' can be obtained by investing in solar/wind supported by pumped hydro or battery storage?

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  7. scaddenp - seems to me the building of new coal plants "anyway" is a serious mistake. Any appearance that they are cost effective are based on an enduring amnesty on the externalised costs.

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  8. A serious problem is the popularity of the "continuity of affordable electricity supply" portion of the following part of the OP.

    "... it is necessary to point out the fallacy of arguments put forward to justify future use of so called ‘clean coal’ fired ultra-supercritical power stations as the best means of ensuring emissions reduction and continuity of affordable electricity supply."

    And the biggest part of the problem is people competing to Win Leadership deliberately making Poor Excuses for unjustified understandably unacceptable behaviour in the hopes that doing so will increase their popularity, increase their chances to win political leadership and Win the ability to get away with 'more profitable/less acceptable' ways of doing things.

    Unjustifiably 'affordable/cheaper' energy supply should not be allowed to be excused just because 'it is what people have developed a taste/preference for'.

    The 'undeniably less acceptable but cheaper' electricity supply over-developed in well developed places like Australia should have been ended a long time ago. The basis of that understanding was internationally established in the 1972 Stockholm Conference (more damage than the CO2 impacts, and ultimately unsustainable - not ways of living that the entire global population can develop to enjoy forever).

    And the scientific basis for that understanding has steadily strengthened since that time. The current best understanding of the required chnages is presented in the 2015 Sustainable Development Goals (with the Paris Agreement being an important step toward achieving the climate action goal).

    A Good Reason for continuing CO2 production from electricity generation wold be as a transition step for the 'sustainable' development/advancement of less fortunate people to better lives. However, nations with more than enough wealth to have their entire populations live decently, like Australia, have no legitimate justification to continue benefiting from burning fossil fuels. They certainly should not be able to excuse building new fossil fuel burning capacity. Those nations need to be reducing the benefit they get from creating any additional CO2 from burning fossil fuels rapidly to 'zero', even if doing so means that their electricity costs go up significantly (And the existence of less fortunate people due to inequity of distribution of wealth within such a nation would not justify that nation collectively being allowed more CO2 emissions. And that evaluation of inequity of wealth also needs to be applied to limit what is allowed in the developing nations).

    The higher cost of electricity is what such 'supposedly more advanced nations' should have adapted to long ago. It would motivate the reduction of 'less necessary' electricity use and the development of lower cost 'acceptable' ways of generating electricity.

    That understanding of the unacceptability of 'Ways of Winning' that the currently perceived to be more fortunate people have developed popular regional support for is very important. The related understanding that clearly has to become 'more common knowledge' is that 'it is undeniably easier to regionally temporarily drum up popular support for beliefs that excuse less acceptable attitudes and actions than it is to properly raise awareness and understanding'.

    As an engineer, applier of science - constantly improving awareness and understanding of what is going on, my job is to first exclude unacceptable alternatives from consideration regardless of the desires of clients and those higer up in my work organization for things that were cheaper or quicker - never allowing cheaper or quicker to be considered to justify a less acceptable option, cheaper and quicker to achieve the required objective was all that was allowed. And if it was ever discovered that a previous way of doing things was actually producing an unacceptable result then nothing new would be done that way and previously done things would 'get corrected' no matter how unpopular or unprofitable that 'change' would be.

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