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Why Coal Is Not Our Future

Posted on 15 December 2016 by Riduna

Coal Problems

Australian Prime Minister, Malcolm Turnbull, has repeatedly asserted that coal will remain in use for electricity generation for ‘many, many decades to come’. He argues that moving to renewable energy would reduce production and use of coal resulting in unacceptable loss of mining and transport jobs, particularly in rural areas. However, the threat of larger job losses did not stop his predecessor from withdrawing subsidies for the car industry, resulting in its closure nationwide - action supported by the present Prime Minister.

Recently, Energy Minister Friedenberg asked Australia’s Chief Scientist, Dr Finkel, to prepare a Discussion Paper on electricity security during the transition to renewable energy. The Paper, presented to the Prime Minister and Premiers on 9 December, 2016 recommended that an energy intensity scheme be applied to the electricity generating sector. This would see the highest emitters leave electricity generation and promote orderly replacement of coal by gas and, increasingly, renewable energy generators.

The Paper reported that existing policies lacked clarity and certainty for investors and would not achieve Australia’s commitment to reduce greenhouse gas emission by 26-28% below 2005 levels by 2030, given under the Paris Agreement. Even before recipients of the paper had time to consider it, the Prime Minister rejected its main conclusions.

In declaring coal Australia’s present and future energy source, Turnbull has chosen to ignore the dangers of coal production and use to public health or, more accurately, public death. Clear evidence shows that coal mining in Australia not only causes respiratory problems through inhalation of airborne particles but that this results in the incurable ‘black lung disease resulting in a slow and painful death. Its combustion in power stations results in emissions which increase the incidence and severity of health problems among populations living up to 100 km away.

As the Prime Minister knows, coal has to compete with renewable clean energy sources, particularly solar and wind. It’s a no brainer of course. Coal has to be purchased at a price which sustains production, while sunlight and wind are free. At present coal can compete because neither solar or wind can do what coal does – reliably produce electricity 24/7. What clean energy sources can do and are increasingly doing, is make inroads into the amount of electricity generated by coal or other fossil fuels, thus reducing the amount of coal burned for this purpose.

The operative words are “at present”. At present, coal relies on the fact that electricity can only be stored to provide for a few hours demand, or at most a day or so. Given the location of wind and solar farms, it is quite possible that neither wind nor sunshine is continuously available to keep them operating 24/7 and when this occurs, coal fired power stations must be available to provide any shortfall. But will this always be the case for the ‘decades to come’ which Malcolm Turnbull assures us is the time span for on-going use of coal? Well, no.

Energy Storage

 Fig. 1. Solar-thermal generator operated by Sundrop Farms at Port Augusta, South Australia. Sunlight concentrated by 23,000 mirrors on to a 128m high tower heats salt until molten. This is then stored in tanks near the tower and used to produce steam for electricity generation.    Photo: Timeline Photos

Energy is at present largely stored in one of four ways:

  1. As molten salt heated by concentration of solar energy, depicted above:
  2. As solar or wind generated electricity, stored in batteries and released to meet demand when the energy source is not available. It is the latter which is of short-term importance to consumers.
  3. As unused capacity of fossil fuelled power stations, particularly those burning gas, to meet shortfall in generation or increase in demand
  4. As water pumped uphill by electricity generated from renewable sources then released to turn a turbine producing hydro-power:

Solar energy is concentrated and focused on an elevated point where it converts water to steam and salt to a molten state. The former is used to drive a turbine, the latter is stored and used to convert water to steam when the sun is not shining, enabling 24/7 electricity generation.

The solar concentrator facility operated by Sundrop Farms at Port Augusta, South Australia generates 39 MW of power and provides a reliable, continuous electricity supply used to operate a desalination plant, pump water, maintain temperature of greenhouses and supply residential and business premises.

The wide distribution of wind-farms makes it unlikely that this source will be becalmed and cease generating electricity nation-wide, however it is likely that lack of energy from this source will fail to meet regional or local demand 24/7, so it is essential that back-up be provided in the form of stored electricity.

Of greater importance is the need for back-up of electricity generated by solar panels since these only operate when the sun is shining. Public policy should require solar farms to be supported by fossil fuelled generators or include appropriate battery storage to ensure that in the absence of sufficient solar energy, continuity of electricity supply is provided.

The National Grid in Australia presently relies on back-up from existing fossil-fuelled power stations, many of which generate electricity at less than full capacity because cheaper electricity generated by renewable sources (wind, solar and hydro) is available. As the number of renewable power sources increase, demand for more expensive fossil fuelled electricity falls, ultimately leading to closure of the least efficient power stations.

This process has already begun with closure of all coal fired power stations in South Australia, though gas-fired generation continues in that State and the planned closure of the Hazelwood (Victoria) power station in 2017. Loss of generating capacity resulting from these closures is more than compensated for by the increasing number of fossil-fuelled power stations already operating below capacity.

Over the next 10-20 years electricity generated by renewable sources will increase both in Australia and globally, resulting in gradual closure of all remaining coal-fired power stations and, as this occurs, the need for backup provided by battery storage will increase. Battery storage is already available in two sizes: domestic and utility.

Domestic Battery Storage


 Fig 2. The Tesla PowerWall 2 is the best known domestic storage battery unit and with a capacity of ~14 kWh, is able to meet the electricity demands of an average 3 bedroom home. In the USA it sells for $5,500.    Photo: Google

Small scale battery storage first became widely available in 2015 with marketing of Tesla’s PowerWall for houses, offering storage of 7 kWh, scalable. In less than 12 months, the same product became available with storage of 14 kWh, at the same price, both products confirming the start of a battery revolution. Competition in storage capacity and battery production is ongoing and will ensure further improvement and falling price for domestic storage to the point where the average 3 br. dwelling with solar panels could be self-sufficient and become largely independent of the grid.

The German company Sonnen GmbH offers 16 kWh storage for domestic use but is more expensive than Powerwall. Mavero batteries, produced by Kreisel GmbH have a capacity of 8 – 22 kWh but are also more expensive than Tesla batteries. It is likely that over the next 5 years, these and similar products will become cheaper, smaller and more reliable as a result of technological developments now on the verge of commercialization.

In Australia, over 16% of households or some 1.5 million dwellings, have solar panel displays – and that number is growing. If less than half of these equip with battery storage over the next 4 years, they represent a significant source of renewable energy, potentially available to the National Grid, at prices competitive with those offered by coal-fired generators.

This could enable the Grid operator to purchase electricity required to meet peak demand of other consumers during the day and sell to households during off-peak periods, usually at night – and do so at commercially attractive rates.

This arrangement provides the grid with an additional tool with which to ensure that energy levels in the grid are maintained at appropriate levels and can wholesale at lower prices. It further reduces demand for coal fired electricity generation and is likely to result in these generators operating at well below full capacity until the least efficient among them can no longer operate profitably, and closes. A result of this is that demand for coal by electricity generators will decline as battery prices fall and their capacity and uptake by dwellings rise.

Utility Scale Storage


 Fig 3. Electricity storage is widely used by utilities in Japan, the USA and the EU, enabling storage of electricity which can be released to the grid during periods of generator downtime or to meet above normal demand on the grid.    Photo: NGK, Japan.

Existing availability of fossil fuelled surplus generating capacity ensures continuity of supply to the National Grid. However, as the least efficient coal fired generators close and renewable energy sources increase, the need for intermittent generators (solar-PV and wind) to supply energy 24/7 increases. This can only be provided if these utilities are equipped with electricity storage able to provide supply when generators are not operating or when demand exceeds supply.

Storage units with this capacity are already used by many larger utilities. As shown above, these are presently large units, with scalable capacity. They are widely used to maintain grid balance and to ensure continuity of supply when generators are no longer in operation. They are particularly important for extending output profile of solar power stations, such as those at Broken Hill and Nyngan to better meet the demand profile at those locations.

Very large scale storage, virtual power stations, such as that being developed for Adelaide, South Australia has a capacity of 5 MWh. Like solar-photovoltaic power plants, they can be located close to the communities they supply. It is likely that as improvements are made in storage capacity, virtual power stations of much larger capacity will become an increasingly common feature able to ensure both grid balance, continuity of supply and security of distribution in the event of grid damage by increasingly severe climate events.


Advances in research, development and commercialization of new technologies are rapid, indicating that cheaper more efficient photovoltaic cells are likely to be available within 5 years. Most commercially available photovoltaic cells convert 15% - 20% of the sunlight falling on them into electricity. Research undertaken at the University of NSW and at the Technion in Israel have produced cells with almost twice this efficiency. Research into production of efficient, flexible Perovskite cells is also likely to lower the cost of solar generating and exceed the efficiency of silicon cells.

Electricity storage facilities are likely to become more compact, have increased capacity and be available at a lower price within a decade as the latest battery technology is commercialized. These developments and increasing competition is likely to result in wider up-take of batteries by households and small business resulting in more efficient use of renewable energy and further rapid reduction of reliance on coal and other fossil fuels for electricity generation.

Among the highest greenhouse gas emitters in Australia are coal fired power stations, most of which are operating beyond their design life span, making them less profitable to operate and increasingly uncompetitive with solar and wind farm generators. It is cheaper to replace these stations with solar photovoltaic or wind, the only disadvantage being that the latter are intermittent generators, a problem now being resolved by use of utility-scale battery storage and solar concentrator generators, accompanied by changes to the way the grid is administered so as to minimize the effects of damage to any part of it.

Investment in new power generators in Australia are very likely to be in renewable sources, not coal, for two reasons: 1. Production and use of coal is hazardous to health and contributes to dangerous global warming and climate change: 2. Advances in technology, already made and pending, make electricity generation from renewable sources practical and commercially more attractive.

The Prime Minister asserts that coal will remain in use for ‘many decades to come’. It is more likely that coal use in Australia could reduce to zero by 2030, replaced by renewables and possibly a few existing power stations which have converted to gas. The transition away from fossil fuels has begun, it will accelerate with technology advances and it will be observed and adopted by other countries now dependent on fossil fuel imports.

So, no Prime Minister, it is unlikely that coal production and use for electricity generation in Australia will last for decades to come – maybe one decade but even that is questionable.


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Comments 1 to 22:

  1. > with a capacity of ~14 mWh, is able to meet...

    I think you mean kWh.

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  2. One has to be careful: mW is milliwatt and MW is megawatt.

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    Moderator Response:

    [PS] The Tesla Powerwall 2 has capacity of 13.5 kWh. The article is in error.

  3. Bernhard - I do mean kWh.  Correction made.

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  4. That Telsa pwall install looks like a demo, not a customer install.

    Doing that on your house is akin to stapling a $5,000 bill on the side, while also adversising that you have the latest and greatest tech stuff inside.  Clearly, it's hard to imagine anything going amiss with that setup. 

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  5. A good article in Vox on why coal makes no sense to build new coal plants, at least in the USA.

    Why renewables and natural gas are taking over the US

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  6. Driving By: if you're going to worry about that, you'll have to hide the Tesla sitting in the drive, erect a trellis around the battery pack, install a state-of-the-art security system,* invest in a doberman and move to a grotty neighbourhood (that probably has more problems with burglaries anyway)

    * which you probably have already.

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  7. I wonder if we will be in time.  Curiously, this year, despite the output of Carbon dioxide into the atmosphere flat lineing or slightly reducing, the concentration in the atmosphere took a jump of almost twice previous years (ref. Mana Loa Carbon dioxide website).  Is this just a temporary phenomenon, possibly caused by the recent El Nino or are one or more sinks shutting down.  The next couple of years will tell.  If it continues, we are in a spot of bother.

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  8. Drivingby, fair point, but most people would put the tesla power pack out of sight at the back of the house. You wouldn't put it by the front door, as it would look unattractive, like a heat pump, and as you say it would be an invitation to burglars.

    I also dont think people will be buying these just to be fashionable. Most will be genuine.

    This power pack is $5,000. Given that new homes can easily cost half a million, this is almost nothing.

    What intrigues me is what will win the battle? Traditional centralised electricity supply or self sufficient homes?

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  9. Do the maths. 

    The cost of utility-scale batteries is huge, whether expressed in dollar terms or resource utilisation numbers.

    The costs of gas fired generation to support wind and solar when the wind isn't blowing or the sun isn't shining is huge also - again both in dollars and in gas consumption and hence CO2 and CH4 emissions.

    The cost of additional HV interconnectors necessary to push the electricity from where it able to be generated to where it is needed is also directly a consequence of and thus the responsibility of the wind farms and their locations.

    If you aren't already convinced about the cost of interconnectors, consider recent South Australian experience, which is directly attributed to the loss of supply for a whole state after weather caused the loss of almost 40% of its (wind) generating capacity and thus overloaded the Heywood Interconnector, which tripped.  Current recommendations are that additional interconnectors be constructed to duplicate existing ones between SA and NSW/Vic; Vic and Tas; and NSW/Qld. The cost?  Estimated $4B to $5B Australian (say 3 to 3 billion US).

    More maths: Why subsidise wind to the point where its proponents then say that it is "cheaper"?  Subsidy: $90/MWh (LRET).  Wholesale market prices: $40/MWh and upwards.

    The winners are the non-Australian manufacturers of wind turbines, etc and those who (again, not Australian, in the main) own and operate fossil fuelled, polluting gas turbines that are essential to the scam/scheme.

    Yet we are forbidden by law from considering nuclear power on its own merits.


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    Moderator Response:

    [PS] Just raising some flags before this discussion goes completely off the rails:

    Firstly, please cite the sources of numbers so others can verify your mathematics should they wish. Unsupported arguments are simply sloganeering.

    Secondly, any further responses on nuclear should be restricted to cost analysis. Those wishing to debate the larger pros and cons of nuclear power should do so over at BraveNewClimate not here.

  10. Typo: interconnector cost should read "say, $3 to $4 billion US."

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  11. Riduna, this is a big thumbs up for me because I like to see solutions. We can do this, and sincere deniers will embrace the challenge, once potential and viable solutions are apparent, then we can be on our way to managing the planet positively, not destructively. The concentrating of human civilization into cities seems to be well on its way; sprawl is one of the biggest causes of our load on the planet, so we are solving the problem on two big fronts. We can do it, the more we focus on solutions the faster our success will materialize.

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  12. SingletonEngineer, the costs of a renewable grid are not astronomically higher than nuclear and are only slightly higher than coal. I base this on an analysis by Forbes, who certainly dont particularly favour renewable energy and the analysis is about 5 years old. And we all know costs of renewables is dropping quite fast.

    You also have to consider nuclear energy does carry the possibility of catastrophic risk. At some level this has a "cost" that needs to be considered. Im not totally opposed to nuclear but all factors must be considered.

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  13. SingletonEngineer

    Please don't talk about subsidies for renewable energy when fossil-fuel producers are not only subsidized to an enormous extent but also pay nothing for the effects of the poisons they inflict on society and the planet.

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  14. Digby - Quite Right!  Compared with global subsidies for fossil fuel exploration and production ($88 bn/year), Australia pays out a modest $4bn/year, of which some $1.8bn/year goes to coal

    This sum does not include the cost of health care for those involved in production and use of coal, the value of water used in the process, or its effects on the environment.  The latter includes global warming of the atmosphere and oceans and all that entails, including damage to coral reefs, the biosphere and food production.

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  15. Nuclear is subsidised by defence interests and the Americans won't let us use it. Thus, it has no financial legitimacy to put it one way!

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  16. "So no Prime Minister, it is unlikely that coal production and use for electricity generation in Australia will last for decades to come – maybe one decade but even that is questionable."

    This is fantastic news. The problem of CO2 emissions is going to go away on its own. No need for Carbon pricing or any type of government intervention to solve the problem. And closer to home, no need for websites like skepticalscience or realclimate to counter the influence of global warming/climate science denialists because there is no need for political action anymore.

    And if you believe that then you've never heard of Pollyanna and her statements reminiscent of the quote above.

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  17. The problem of CO2 emissions >is< going to go away on its own... eventually.

    Indeed, that has always been the case. If nothing else, we will eventually run out of fossil fuels to burn.

    However, that does not mean that we can just kick back and wait for it to happen. Indeed, the whole point is that we need to deal with global warming before it gets to the point that it is self-correcting.

    Coal is obviously on its way out. It will not be a major component of electricity production anywhere in the world "decades" from now. However, how quickly we phase it out, to say nothing of oil and natural gas, is still very important.

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  18. Chris O’Niell - The sentence you quote refers to coal use for electricity generation in Australia only. It does not refer to global use of coal for this purpose or metal smelting, though some major users may be reducing consumption.

    Global production and use of oil and gas are equally significant contributors of greenhouse gases, as are other anthropogenic activities, such as farming and damage to carbon sinks.

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  19. I've got a deposit on a Tesla Model 3.  I'm going to have bumper stickers made that say, "Powered by American coal."  If anyone wants one, let me know.

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  20. Electric vehicles make coal more viable and cheaper. Cars can be charged at night which will improve utilization of existing coal-fired power plants.  Producing more power without capital expenditures using the cheapest fuel available is going to make electricity cheaper at the same time demand is increasing.  The coal and natural gas industry should be all for EVs.  

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    Moderator Response:

    [PS] This is really getting into sloganeering and verging on trolling. To support that slogan, you need to show that unsubsidized cost of coal generation is lower than other forms. Useful resource would be here.

    Make sure you back any assertions you are making with appropriate evidence or risk getting your comments deleted.

  21. Andrew... Being that there are no markets that are 100% coal, how do you justify that statement? Are you going to erect a small coal fired generator in your back yard? 

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  22. @ 19,

    I would simply ask why someone would bother doing that. Are you trying to say something about the methods of applied science versus the methods of mixed markets?

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