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, well, the concept is a unicorn: a lovely idea, but the stuff of fantasy.
No viable technology exists that allows coal to be burnt without adding significant carbon pollution to the atmosphere. However, the Australian coal sector and its subsidiary, the federal government, use the term “clean coal” to refer to two technologies:
- High Efficiency, Low Emissions (HELE) coal plants — i.e. those using “supercritical”, “ultra-supercritical” and “advanced ultra-supercritical” technology.
- Carbon Capture and Storage/Sequestration (CCS) — i.e. various technologies to capture a power plant’s CO2 emissions and store it permanently underground.
LNP backbencher George Christensen said on Wednesday that he’d rather the government rolled up its sleeves and built “clean coal” power stations instead of pursuing Finkel’s Clean Energy Target, and that his plan would reduce carbon pollution. How broken is our system when someone we pay $200,000 p.a. is betting our climate and energy future on the existence of unicorns?
[In Christensen’s Soviet Union, coal-fired power burns you!]
It’s time we took the CCS/coal unicorn ’round the back and shot it. While CCS may have an important role to play in decarbonising some industrial processes, CCS on coal-fired power stations is a non-starter.
Given the hype, take a guess of how many large-scale CCS/coal power stations there are in the world …
There are just two. Six weeks ago, Federal Energy Minister Josh Frydenberg visited the newer of the two, the US$1 billion Petra Nova project at the WA Parish power plant in Texas, where he proclaimed that the project was “helping to reduce the carbon footprint by some 40%”. Do just a little homework and you’ll find that the CCS plant is only reducing the plant’s net CO2 emissions by just 4.5%, and only comes close to making sense with a carbon price well over US$100. The economics are a little worse for Saskatchewan’s Boundary Dam power station, the only other large scale CCS/coal plant in the known universe.
The coal sector would prefer you didn’t know about the Kemper project, which may soon become the world’s third CCS/coal plant, but here’s a quick summary: it’s small (528 MW net), has similar emissions to combined cycle gas but is 16 times as expensive, is US$5.7 billion over initial budget and a decade after receiving its first tranche of taxpayer largesse, it still doesn’t work.
There are no other significant CCS/coal plants under construction elsewhere in the world. If you still think there’s a chance that anyone will build a CCS/coal power station in Australia, here’s a bit of extracurricular reading.
So what about HELE?
We actually have four HELE power stations in Australia. Let’s take a look at these ‘clean coal’ power stations. All four are in Queensland, built this century and burn black coal using “super-critical” steam technology.
Together the Australian “clean coal” fleet makes up 14.1% of all of our black coal power generation.
To put the emissions intensity numbers into context, we can compare the ‘clean coal’ fleet against our 14 non-HELE black coal power stations that use older “sub-critical” steam technology.
NB: The three brown coal power stations in Victoria — Loy Yang A, Loy Yang B and Yallourn — as there are no HELE/brown coal plants in Australia to compare against.
NB: 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 just 9.95% less pollution per unit of energy than stations burning the same fuel with regular sub-critical technology.
For those lost in the numbers, let’s get graphical. The chart below shows the intensity of each Australian black-coal fired power station plotted against its year of construction. The dot area is proportional to the energy produced in the sample year (2015-16). Australia’s four HELE power stations are represented by green dots (because they’re “cleaner”, of course).
Simon it’s a pity you didn’t feel naughty and put the emissions for solar in yellow dots on the graph just for good measure!
@mike — i should have done that! i wanted to put in a line at 820 kg CO2-e/MWh, being the NEM average, but datawrapper wouldn’t do it for me.
Agreed, there is just too much excess CO2 to be stored. However, captured CO2 can be recycled (eg “Fischer-Tropsch”), given copious non-carbon electricity. Synfuel has a market in the remaining combustion engines such as aviation. Also, carbon anodes are needed in aluminium smelting and potentially other metal smelting, such as as iron.
@roger how do you turn CO2 into carbon anodes? and what would you do with 28 million tons a year — Loy Yang’s output alone…
“How do you [efficiently] turn CO2 into carbon anodes?’ – yes, a good R+D question, one that industry should be throwing money at. Currently, carbon is produced as a byproduct of a fuel refinery, so presumably the chem engineers in a synfuel refinery would rig a stream to supply the demand. A difference between the two refineries would be the enormous (~50 MJ/kg) amount of non-carbon energy required to replace the oxygen with hydrogen.
In an ideal world, as much CO2 would be captured for reprocessing as reprocessed carbon was burnt. Then no new fossil carbon would enter the greenhouse.
so, easier to leave in the ground?
The “clean coal” lobbyists are …..(what I’d like to write is too rude to put into print).
They’ll cling on by their finger nails whilst trying to pretend it’s a great idea. Too bad it won’t work for them. It’s very nasty having your nails ripped back to the quick.
What do you call people who play with bullshit …. or any kind…?
Frydenberg, Turnbull, Hunt?
The main problem with Carbon Capture and Storage is not technical but stems from the basic chemisty of combustion and the scale of the reverse-mining of the CO2 that is implied.
It is technically possible to spend money and energy to extract carbon dioxide from the flue gases of coal-fired power stations. For every tonne of coal burned you will be faced with 3.7 tonnes of CO2 to extract and the numbers are pretty similar for any fossil fuel.
The big question is what you are going to do with the CO2 once you’ve collected it. You’re going to need to spend more money and energy to compress it and store it temporarily. You then need to spend money and energy transporting the CO2 to a repository where it can be sequestered from the environment for geological time frames. Presumably we’re talking about injecting it into (as yet un-identified) subterranean geological structures and more money and energy will be spent pressurising and injecting the CO2 underground.
CCS implies a reverse mining operation that dwarfs by a factor of at least four the coal extraction that it needs to neutralise. Every truck, train or ship-load of coal brought to the power station will require four equivalents to carry the CO2 away.
Do you believe (can anybody honestly believe) that an industry-scale CCS operation would leave any energy or financial viability in coal as an energy source?
It’s frustrating that proponents looking for public investment in CSS are not being challenged publicly about the basic parameters of CSS that make it a clear dud. It would be a tragedy if any public funds were wasted on this boondoggle.
i get your general argument — and it is a very good one — but your multiplier isn’t quite right.
the ‘expansion’ factor for pure carbon is 3.67, for sub-bituminous coal it is 1.87