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How clean are Australia’s ‘clean coal’ power stations?

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What’s that you say? Australia has ‘clean coal power stations’?

Well, it depends how you define ‘clean coal’. Most power sector observers eschew the phrase because frankly it’s misleading. No technology exists that allows coal to be used without adding carbon pollution to the atmosphere — however the Australian Government and the Australian coal sector use the term ‘clean coal’ to refer to two technologies:

  • High Efficiency, Low Emissions (HELE) coal plants — ie. those using supercritical, ultra-supercritical and ‘advanced ultra-supercritical’ technology.
  • Carbon Capture and Storage/Sequestration (CCS) — ie. various technologies to capture a plant’s CO2 emissions and store it permanently underground.

There are no CCS power stations in Australia. In fact there are (generously) only three in the world, and given the massive costs and time required to build, I’d happily wager that we won’t see any in Australia any decade soon. (See my answer to How many CCS electricity generators are operational globally? How much CO2 do they sequester annually, and at what cost?)

However we do have four HELE power stations in Australia, all are in Queensland and burn black coal with super-critical steam technology:

b. Unfortunately detailed information for the Worsley power station is not readily available, however as it only represents 1.2% (by capacity) of the black coal sub-critical fleet, it has negligible bearing on this analysis.

Together the Australia ‘Clean Coal’ fleet makes up 14.1% of all black coal power generation.

To put the emissions intensity numbers into context, we can compare the ‘Clean Coal’ fleet against black coal power stations using older sub-critical steam technology.

nb. For this comparison I’ve excluded the three brown coal power stations in Victoria — Loy Yang A, Loy Yang B and Yallourn — as there are no brown coal HELE plants in Australia.

We have 14 non-HELE power stations that burn black coal:

nb. Unfortunately detailed information for the Worsley power station is not readily available, however as it only represents 1.2% (by capacity) of the black coal sub-critical fleet, it has negligible bearing on this analysis.

nb. Unfortunately detailed information for the Worsley power station is not readily available, however as it only represents 1.2% (by capacity) of the black coal sub-critical fleet, it has negligible bearing on this analysis.

The average emissions intensity (weighted by electricity production) for the two technologies are:

  • super-critical, or HELE (‘clean coal’) — 919 kg CO2-e/MWh
  • subcritical, or non-HELE — 1011 kg CO2-e/MWh.

Therefore Australian power stations fitted with ‘Clean Coal’ technology emit 9.95% less pollution than stations burning the same fuel with regular sub-critical technology.

For those lost in the numbers, perhaps it’s better to show this graphically. The chart below shows the intensity of each Australian black-coal fired power station plotted against its year of construction. The larger the dot, the greater the energy produced in the sample year (2015-16). The green dots represent Australia’s four HELE power stations.

 Those paying close attention might notice that these emissions factors are 10–15% on average above those quoted in some other sources. The tables above calculate the ‘sent-out’ energy, which subtracts the significant self consumption (or ‘auxiliary power’) of the power stations themselves. Some other sources use the total (or ‘as generated’) output, thereby underreporting the emissions intensity.

But isn’t HELE supposed to be a part of Australia’s energy solution?

So we are told. The table below underpins much of the enthusiasm by the government and the coal sector:

main-qimg-e0ba8b72f2691fad20b4edb69b654008

It’s worth noting:

  • None of Australia’s HELE plants fall within the 800–880g CO2/kWh (equivalent to 800–880kg CO2/MWh) range. This is most likely due to the discrepancy between ‘sent out’ and ‘as generated’ energy, as mentioned above.
  • Comparing the CO2 intensities for subcritical and supercritical technologies listed in the table, we see that super-critical plants are approximately 9.5% more efficient. This is reassuringly in line with the Australian empirical data.

So what about ultra-supercritical and advanced ultra-supercritical?

China leads the world with ultra-supercritical technology — 19% of current coal generation capacity and 58% of coal generation capacity under construction is using the technology, yet outside of China the take up is much lower: 4% of operating capacity and less than one third (29%) of capacity under construction.

India’s has just 600 MW of ultra-supercritical capacity under construction.

There’s only one ultra-supercritical power station in North America, the John W. Turk Jr. power station in Arkansas. At US$1.8bn for a relatively small 600 MW plant, the Turk power stations is the most expensive power project ever built in the state. As well as being the first ultra-supercritical plant on the continent, it currently holds the dubious distinction of being the last, at least for the time being.

The ultra-supercritical Unit 3 of the Danish Nordjylland Power Station claims to hold the world record for most efficient coal utilisation. Interestingly, Australia has built five coal power stations since Nordjylland was commissioned and none have used ultra-supercritical technology.

Perhaps the main reason we haven’t seen ultra-supercritical technology applied more widely, and not at all in Australia, is that the technology costs 20–30% more than subcritical technology. Except in regions with very high coal costs — or very high carbon pricing — the economics simply don’t stack up.

So what of advanced ultra-supercritical technology?

Advanced ultra-supercritical is still in the early stages of research and development. Exotic and expensive materials are required to withstand the significant increase in temperature and pressure.

The Technology Readiness Level (TRL) methodology is an widely used benchmarking tool originating at NASA for “tracking progress and supporting development of a specific technology through the early stages of the technology development chain, from blue sky research (TRL1) to actual system demonstration over the full range of expected conditions (TRL9).”

main-qimg-506e047c56af66f536ad2068ddec890f

The chart above lays out the TRL and Commerical Readiness Index (CRI) as adapted by the Australian Government.

Any capital intensive technology will not find mass adoption until it is ‘bankable’, but first it must move through the TRL scale and ultimately up the CRI scale.

India is investing US$230m in advanced ultra-supercritical R&D and hopes to have a demonstration plant up and going by the end of the decade. It’s fair to say that advanced ultra-supercritical is still at the low end of the TRL scale and when each implementation can cost well in excess of $1bn, the path through technology readiness to commercial readiness will require decades of patient investment.

Between 2011 and 2014, a US Department of Energy funded trial demonstrated 17,000 hours of operation of advanced ultra-supercritical temperatures and pressure on Unit 4 of the James M. Barry Electric Generating Plant in Alabama.

As well as the US and Indian research, Japan and and the EU have invested in advanced ultra-supercritical research and development.

However the economics are unconvincing and getting worse. Massive investment is required to make a technology that is marginally less polluting but more expensive than current coal technology — a technology that is being undercut by renewable energy by ever increasing margins.

Coal power generation in Australia has peaked and there are many reasons (beyond the scope of this piece) why the decline is terminal.

HELE has been touted by some as the saviour of the coal generation sector, yet the technology’s only hope for a strong future is very high carbon pricing. Somewhat ironically, the key cheerleaders for HELE — the Australian Government and the coal industry — have been the lead players in killing off all efforts to properly price carbon pollution.

  

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  • john

    Part of the cheerleaders group is touting building a “clean coal” generator in the north of Australia.
    No doubt the spokesmen will cloud the issue to such an extent the average Joe will think it means they wash the coal clean.
    This is not a joke it was not that long ago an actual worker in the industry used the very term, “We sell the cleanest coal in the world we wash it”.
    With the probability that CST plants will be built as well as solar battery and solar hydro storage on top of pumped hydro expansion, I feel that no new coal plants will be commissioned.

    I do take note of the real outcomes where the output of the generators against carbon emissions is the more accurate figure to work on.

    • Rohan Bussell

      “With the probability that CST plants will be built as well as solar
      battery and solar hydro storage on top of pumped hydro expansion, I feel
      that no new coal plants will be commissioned.”
      Its very unlikely that any new coal plants will be built in Australia while the RET exists. Government policy is the main driver of that fact.

  • ben

    What’s the LCOE for those technologies?

    • Simon Holmes A Court

      i’m trying to find that out ben. there’s research showing $120 for a retrofit — on top of the cost of the energy, i.e. $168 for NSW coal.
      see pg 176 of the 2015 australian power generation technologies report.

  • Ken Dyer

    How many times does it need to be said? There is no such thing as clean coal. Period.

    • Rohan Bussell

      It has to be noted that people are almost totally obsessed with CO2, not the other pollution associated with the technology. The CO2 net social cost is not something that has been satisfactorily answered to my liking. There is an assumption that it could vary anywhere between a few USD per tonne to US$50 per tonne, but there is a dearth of readily available literature on the subject, what is available is unconvincing.

  • So refreshing to read an article that is based on demonstrable facts.
    To me this type of editorial is what we need to see in the greater media.
    In a similar vane, we keep hearing that the RET is responsible for the massive rise in electricity cost but I have yet to see any substantiation, probably because there isn’t any.

    • Peter Campbell

      Refreshing to just see a graph with the origin at zero!

      • Farmer Dave

        I agree!

    • Rohan Bussell

      “…we keep hearing that the RET is responsible for the massive rise in electricity cost…”
      It is not the only reason, but it is an important reason for the increased costs. For a significant period of time in SA, no new non-renewable capacity was added, existing capacity was shutdown. 3 coal plants have shutdown that supply SA, 1 gas unit that was mothballed has been reactivated. The companies that added renewables, particularly wind, were under no obligation to provide security to the market…in fact the market (customers and utilities) had to provide security to them.
      SA has basically succeeded in ramping up to a high wind share because it could buy its shortfall when needed from Victoria. AEMO has also basically officially declared that SA cannot function as an island…it depends completely on the interconnector…and that was proved by the storm outtage; which in itself raises the issue of building 30 – 50 year infrastructure without proofing it for even a once in 50 year event.
      In amongst that there are gas price rises, increased cost flowing through from temporary generation, opportunistic price increases from utilities, the increases that came from the anticipated carbon tax/ETS…etc.
      I think companies have behaved rationally, but i think the government naively believed that somehow companies were going to just spend more to offset intermittency out of the goodness of their hearts…it is to be expected that the government has had to intervene and either buy more generation themselves (gas peaker, diesel and batteries) and tender forward contracts that leads to new capacity (solar thermal). The private sector isnt stupid, theyre not gonna build a baseload and run it at a loss, theyre not gonna spend big money installing storage if they can get away with waiting for the government to do it.

      • Brian Tehan

        SA cannot function as an island – nor can nsw – so what? That’s why we have a an East Coast grid – it means less wasted generation capacity, therefore lower capital costs and higher reliability.
        SA actually has plenty of fossil fuel capacity, in the form of gas generation. It’s just that gas has become very expensive and some of the operators sold off their allocation on the market. It can also be quite difficult to persuade them to turn on generators when required. This is all documented within the articles on this site and also by Michael West.
        The Liberals privatised the power system years ago, causing most of the current problems, and the state government has been forced to invest to wrest some control back, so the people of SA won’t be held to ransom at peak times.
        Your assertions seem to show a misunderstanding of the issues or lack of research.

  • Malcolm M

    There would have to be questions about the reliability and longevity of plants operating at such high temperatures and pressures. Even the old Liddell power station has been operating at reduced output to avoid steam leaks. How does an investor accommodate the risk that its materials won’t last the 30 year investment time-frame at 700 degrees? Does it need a major refurbishment and replacement of materials after perhaps 10 years ? How does a manufacturer test its longevity ? The market would probably lead to short warranties on the materials from the manufacturer, after which most of the risk with the power station investor.

    • The operating pressures and temperature only follow after the materials have been developed and tested. All the design and material criteria are subject to rigorous national and international standards.
      And if you get it wrong, particularly in the US market, you will get the pant sued off you.

    • Rohan Bussell

      How does a high pressure nuclear reactor accommodate the risks of materials not lasting? They choose too and/or are forced by regulators to use very high spec parts and construction materials.
      The fact that many nuclear reactors in America routinely get extensions to their licences to operate greater than 40 years is indicative. Some reactors have had construction issues that warranted early closure, but most keep going…particularly if they are in states that accept nuclear into clean energy targets (ie give them clean energy subsidies).

  • Robin_Harrison

    No chance of competing with RE+storage but plenty of time to feed at the public trough.

    • ben

      I agree with you, by muddying the waters of public policy they can get another 10 years of snout in trough funding

    • Rohan Bussell

      “No chance of competing with RE+storage but plenty of time to feed at the public trough.”
      Im unsure where you get this from. Renewables and storage receive tremendous subsidy under the RET to the point where even efficient CCGT faces problems, but somehow fossil fuel industry are the ones feeding at the trough?
      Perhaps coal is closing down through dying from overeating at the trough…amirite?

      • Robin_Harrison

        The fossil fuel industries enjoy around $5trillion p/a in various subsidies and efficient CCGT is a complete oxymoron. By all means lets get rid of all subsidies.

        • Rohan Bussell

          “efficient CCGT is a complete oxymoron.”
          To say that, you are obviously a leftwing lunatic. Feel free to come back to reality at some point.

          • Robin_Harrison

            Never been a socialist in my life. Very simply, renewable energy+storage infrastructure is at price parity with fossil fuel infrastructure and getting cheaper. There is no chance of CCGT being remotely competitive, therefore it is not remotely efficient.
            Coal is closing down because the technology is redundant. I note your unwillingness to address the massive subsidies handed to the fossil fools. Feel free to come back to reality at some point.

          • Rohan Bussell

            “Never been a socialist in my life.”
            Leftwing includes greenism mate…which you very obviously belong to.
            “I note your unwillingness to address the massive subsidies handed to the fossil fools.”
            Nonsense. You should be very careful with your assertion that CCGT “is not remotely efficient”, because that is just you spouting binary green propaganda. CCGT is a lot more efficient compared to open cycle gas (short term peaker plants). It is also relatively quick to build and cheap in areas where there is plentiful gas supply.
            What you claim is pure greenism, without green subsidies, usually via a RET or CET system, solar pv and wind would have to justify their intermittency somehow…ie with batteries or pumped hydro or solar thermal, the moment they do that the costs escalate. Generally, the cost to build unsubsidized wind + batteries is significantly more expensive overall than just building a combined cycle plant. For example, in Australia the comparative LCOE listed in the most recent report is, a minimum of around A$70 to $80 for combined cycle, ie a baseload style plant; the wind was A$85 or more by itself, not including batteries. To include batteries the price then escalates to about a minimum of $300/MWh.
            The impact of the RET is what makes it possible for wind to sometimes bid competitively into the grid, it helps solar pv and wind that they get their certificates despite not being able to guarantee electricity supply…the nameplate might be 1000MW of wind, the generation may only be 200MW at one point in time.
            Combined cycle gas is a comparatively very efficient and convenient power plant design.
            However, open cycle is very expensive per MW, inefficient and has high emissions. Its only advantage is that it allows averaging with renewable sources and can supply electricity when intermittents cant or for when batteries cant. You may have confused open cycle with combined cycle.
            One phenomenon is that diesel generation is also employed to cover for periods where intermittents cant supply and the price is high.
            If you knew what you were talking about youd know that intermittents displace baseload and encourage load following…so relatively inefficient short term power plants become favored in a renewables environment.

            “Coal is closing down because the technology is redundant.”
            Coal closes down when it is forced to cross subsidize renewables…in the end only a fool would stay open in such an environment if they arent required to by law. Once that occurs, the prices generally increase, hardly what we would expect from a more efficient technology taking over from a less efficient technology.

            As I joked: if they are so fat on subsidies why close down? The answer is that they are not being net-subsidized and protected as much as renewables. As a protectionist policy, renewable targets and the credits it provides are doing their job…probably even more effectively than politicians thought.

          • Robin_Harrison

            I see you still avoid addressing the $5trillion p/a subsidies to the fossil fools you favour.
            Never mind the environment, on purely economic grounds fossil fuel generation is on the point of redundancy. Either you have not been paying attention or you have other motives. Your repeated attempts to brand me with nonsense ideological labels suggest a serious dose of astro turfing. Deliberate attempts to manipulate the mainstream narrative in favour of vested interests. Either you are being paid to disseminate spurious information or you are, somewhat unintelligently, regurgitating this nonsense for free.
            BTW I have no interest in renewables targets or subsidies. The constantly improving economics of renewables are at the stage where they can look after themselves.
            You should try your rubbish on sites with less intelligent readers because it won’t work here.

          • Rohan Bussell

            “Never mind the environment, on purely economic grounds fossil fuel generation is on the point of redundancy.”
            Delusional.
            “Either you are being paid to disseminate spurious information…”
            Ah yes, greeny paranoia.
            “BTW I have no interest in renewables targets or subsidies. The
            constantly improving economics of renewables are at the stage where they can look after themselves.”
            Delusional.

          • Robin_Harrison

            Oh dear, you really aren’t paying attention to the energy marketplace are you? You treat us to more of your spurious ideological labels and you still seem reluctant to address the $5trillion p/a subsidies to the fossil fools you favour.
            Have a nice day astro turf boy.

          • Rohan Bussell

            “Have a nice day”

            So thats the standard of argument Im to expect from the pro-renewable people…eh? Pitiful.
            You keep peddling this nonsene about 5 trillion per year in subsidies…what is that relevant to exactly, im unsure if you even have a clue.

            Intermittent generation does not usually have its unreliability priced. That unreliability is something that would be a normal component of any market driven contract. It becomes in effect, a social cost on the nation, that social cost, similar to the costs of pollution that anti-coal/dirty coal advocates like you claim, should ideally be priced.

            The government generally forgives intermittency to encourage it to eat away at and eventually force out of business its baseload competitors.

            Have a think about that when you claim that fossil fuels just feed at the trough and have all the advantages. As you say, the world has changed, whatever support fossil fuels received before has given way to a hostile system in many jurisdictions that is intent on closing down all coal when they reach retirement and replace that only with renewables. Some jurisdictions are smart enough to include nuclear in that program.

            The subsidy dependence is perverse for renewables, because the moment RET’s are dismantled, unless the governments ban coal and gas, the temptation will be to just build them again. Protectionism for renewables, at this stage, seems to be something we will have to learn to live with as long as that political movement is in charge.

          • Robin_Harrison

            Not quite the standard of argument since you chose to ignore half the sentence astro turf boy. That, by the way, is a categoric accusation that you are deliberately attempting to spread misinformation for your fossil fool mates.
            If you actually believe your rubbish and intend making investment decisions based on it, I urge you to have a closer look at the energy market. However, if you are being paid to do this then I suppose it’s worth your while. Although as I previously suggested, your nonsense would maybe do better on sites with less informed people. BTW Most people on this site are fully aware of the $5trillion p/a subsidies to FFs.
            You might like to get a little more information, particularly if you believe this stuff you’re peddling.

          • Rohan Bussell

            “…if you are being paid to do this…”
            Lmao…you stupid tard.
            I love arguing with greenies like you…I make the arguments and you disintegrate.
            If conspiracy theorism is all you have, youre deeply lost.

          • Robin_Harrison

            So you’re not being paid. Does that mean you’re stupid enough to believe that rubbish? However, your standard astro turf response of formulaic ideological insults and claims of conspiracy theories would argue otherwise.
            Once again, your nonsense would maybe do better on sites with less informed people.

          • Rohan Bussell

            “… your nonsense would maybe do better on sites with less informed people.”
            Youre hardly what i would consider to be “informed”, youre an irrational believer and you fail to back pretty well anything you have said with real information.

          • Robin_Harrison

            The failure is in your reading and comprehension but I’ll give it another go. Here are some facts with not a trace of politics or the environment.
            RE+storage infrastructure cost is rapidly approaching price parity with fossil fuel infrastructure cost and getting cheaper. Even a cursory glance at the energy marketplace will show you that. It will continue to get cheaper for some time and RE+storage can provide all energy needs even more efficiently than present systems.
            As with all disruptive technology since the beginning of the industrial age, the outgoing technology just can’t compete and the growth of all disruptive technologies is exponential so expect the end of the fossil fuel age sooner rather than later. EVs are part of that too but a little further down the growth curve.
            Unless, of course, you expect this disruptive technology to behave differently to every other disruptive technology we’ve ever had. If you base your investment decisions on that you will end up with a lot of stranded assets.
            I could point you to dissertations by people who have studied the effects of disruptive technologies and whose predictions on this disruption have been spot on so far and, if you are at all interested, I will. However, you won’t have to wait long to see the proof of this. There’s unlikely to be any new fossil fuel generation infrastructure built after 2020 and nobody will be buying new internal combustion vehicles beyond 2025.
            You my friend can believe whatever you want but nobody here is going to believe your stuff.

  • The World Coal Association, like “…the Australian Government and the Australian coal sector [the Minerals Council Australia] use the term ‘clean coal’ to refer to two technologies … High Efficiency, Low Emissions (HELE) coal plants — ie. those using supercritical, ultra-supercritical and ‘advanced ultra-supercritical’ technology…”

    …but this is a fairly recent narrowing of the concept. Previously it also included integrated gasification combined cycle (IGCC) power stations.

    Japan and South Korea now build IGCC coal power stations in preference to the older, less-efficient ultra-supercritical coal-fired power stations.
    https://uploads.disquscdn.com/images/0f6e8de700b1ea5091a09948e1ef42f4ea1b28ef965bb3ba2c7478bd48c1f43e.png

    There are two reasons for the coal industry now only promoting the older technology:
    One is that they cannot be as easily switched to natural gas or renewable natural gas. With an IGCC power station, the operator simply turns off the coal gasifier and feeds natural gas directly to its gas turbines.
    The second is that they can’t use low-grade coal of which India and Pakistan have large reserves. An IGCC plant’s gasifier can convert any grade of coal and biomass into gas to run its gas turbines. That, they are preferred by companies that export coal from Australia.

    The Australian Government’s adoption of this marketing material is a reflection of it being a mouth-piece for the coal industry.

    • Rohan Bussell

      The Kemper plant in America was built as gasification and this has been very expensive. It may prove useful as a learning experience, but its yet another example of utilities in america basically experimenting on their customers at their customers expense.

  • MorinMoss

    What about the non-CO2 emissions, such as fly ash, mercury, etc. How much better, or worse are the HELE plants?

    • Rohan Bussell

      HELE is mostly about CO2…obviously with efficiency if less coal is burnt, less other pollutants are emitted.
      However other dedicated mitigating technologies are used to reduce the other substances. Activated carbon for mercury, etc.

  • john cooper

    Saying “clean coal” is as mindlessly stupid as saying i have a “healthy melanoma”.

    • Rohan Bussell

      Its perhaps about the same level of ridiculous as people who imply that wind power is a dispatchable replacement to coal, nuclear and ccgt baseload. Anyone who understands the realities knows thats pro-renewable wank.

  • trackdaze

    10% less!

    • Rohan Bussell

      Gas is about half, but its hard to built CCGT as well…even harder to develop onshore gas or get companies to build more infrastructure domestically.

  • Gary Rowbottom

    Thanks for the analysis – I love it when the numbers come out to play!

    • Rohan Bussell

      The kg/MWh figures in the first table are much higher than the summary figure in the 2017 AEMO FT report. Around 70kg to 120kg more CO2, thats quite a significant discrepancy.