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Climate Hustle

Zero Carbon Australia: We can do it

Posted on 19 March 2011 by James Wight

My recent post about long-term CO2 targets was rather doom-and-gloom: I concluded that we must phase out fossil fuels to keep the climate in the range that humans have experienced. The good news is that action on this scale is not only possible but surprisingly feasible.

Last year, the University of Melbourne Energy Research Institute in conjunction with Beyond Zero Emissions produced the Zero Carbon Australia 2020 Stationary Energy Plan. The ZCA2020 Plan outlines an ambitious and inspiring vision: to power Australia with 100% renewable energy in ten years.

The report that has been released only covers emissions from Stationary Energy (though it does refer to electrifying transport). Five future reports are planned on how to eliminate emissions from other sectors (Transport, Buildings, Land Use and Agriculture, Industrial Processes, and Replacing Fossil Fuel Export Revenue).

Why do it, and why now?

As I’ve explained here, to prevent “dangerous anthropogenic interference with the climate system” we must reduce CO2 to below 350 ppm. That necessitates a rapid transition to a zero-carbon economy.

A common approach is to define a quota of allowable future global emissions to limit warming to less than 2°C above preindustrial levels, and divide them up by nation per capita. At Australia's current rate of emissions, we will use up our share of the global budget in just five years (the same goes for the US and Canada). This gives Australia about a decade to make the transition.

Global Carbon Budget for Emissions

Figure 1: CO2 emissions budget for selected nations.

That’s why Zero Carbon Australia 2020 is not a low emissions plan but a zero emissions plan. This is a fundamentally different way of thinking about the problem. It goes straight to zero emissions technologies, without a detour through low emissions ones which would waste time and resources.

If the Plan is adopted later it could still meet a later deadline. But obviously, further delay means ever increasing risks – and the risks are already very high.

What energy sources would power Australia?

The Plan chose only technologies that can meet demand, can be implemented within ten years, are already commercially available, and (obviously) are zero-carbon, not counting emissions from construction.

60% of the grid would be powered by concentrating solar thermal (CST). The other 40% would come from wind turbines. The Plan also includes small-scale solar to reduce the grid demand during the daytime. Biomass and existing hydroelectric would be used as backups.

Of course, this is only one possible scenario. Technologies that become available in future could increase our options and reduce the cost.

Nuclear power was not considered because the implementation time is longer than a decade. Hydro and biomass are limited in scalability for unrelated environmental reasons. Wave, tidal, and geothermal are promising technologies but not yet ready. Carbon capture and storage is neither commercially available nor zero-carbon.

How would they provide continuous power?

A common misconception is that renewables can’t provide continuous (“baseload”) power. But the technology of concentrating solar thermal can. It was proven at commercial scale in the 1990s. The US Department of Energy lists several dozen solar thermal plants currently in operation.

Here’s how it works. Mirrors called “heliostats” track the Sun and focus sunlight onto a central “power tower”. This energy is stored in molten salt as heat, warming the salt to 565°C. This energy storage has an efficiency of up to 93%. To produce electricity, the hot salt is pumped into a generator, where the heat is transferred to steam which drives a turbine. Once the salt is cooled to 290°C (still warm enough to be molten), it returns to the tank to be reheated.

Solar Thermal Power Tower

Figure 2: Diagram of a concentrating solar thermal power plant.

The Sun doesn’t shine at night, but this is not a problem for a solar thermal plant because it has a store of energy ready to go at any time. CST can produce power around the clock. The ZCA2020 report describes it as “better-than-baseload” because it is more flexible. CST works well with wind power, because the stored solar energy can be used when there is not enough wind.

As the cheapest form of renewable energy, wind can provide a generous portion of our electricity. Because the wind isn’t blowing all the time, wind farms average only 30% of their capacity. At least half of the electricity produced (ie. 15% of capacity) is expected to be as reliable as “baseload”.

Finally, the Plan includes more than enough backup biomass capacity to fill the gaps created by worst-case weather. The hydro and biomass backups are required for just 2% of demand.

The report modeled the ZCA2020 grid, based on real-world insolation and wind speed. They assumed a demand 40% higher than today (accounting for increased energy efficiency and electrification of transport and heating). The modeling confirmed the proposed portfolio of solar, wind, hydro, and biomass would indeed supply demand.

How much solar and wind must be built, and where?

Proposed Power Grid for Renewable Electricity

Figure 3: Map of proposed sites. Yellow squares are solar power plants, blue squares are wind power plants, red lines are high-voltage direct current transmission, and green lines are high-voltage alternating current transmission.

The Plan proposes 12 CST sites, each with 13 major power towers, each power tower with 18,000 heliostats. Together, they would have a total capacity of 42.5 GW and be able to store enough energy to meet winter demand.  

The proposed locations are near Bourke, Broken Hill, Carnarvon, Charleville, Dubbo, Kalgoorlie, Longreach, Mildura, Moree, Port Augusta, Prairie, and Roma. These towns are far enough inland to have high sunlight throughout the year, but close enough to the populated coasts for it to be economical to build high-voltage transmission lines.

Each site would measure approximately 16 by 16 km. The total land used would be less than 3,000 km2. That’s comparable to Kangaroo Island, smaller than some large cattle stations, and 0.04% of the area of Australia.

To provide enough reliable wind power for a 40% target, we need a total capacity of 50 GW, 25 times what it is now. The best commercially available wind turbines have a capacity of 7.5 MW, so we need to build 6,400 of them. Land covered by wind turbines can still be used as farmland.

The Plan proposes 23 sites dotted around the coast. The locations are widely dispersed so the grid is not dependent on the weather in any one place. They are also chosen for high wind speeds in winter, when less solar power is available. Each site has annual average wind speeds of at least 25 km/h.

To put all this in perspective, some other nations are investing in renewables on a large scale. China already has 25 GW of wind capacity and will have 150 GW in five to ten years. Denmark has a target of 50% wind power by 2025. And Spain will have 2.5 GW of solar thermal capacity by 2013.

What is the timeline?

The CST plants would be built in two stages. The first stage would begin by constructing small power towers and gradually ramp up until 2015, when solar power costs become competitive with coal power. The majority of the power supply would come online during the second stage, with a constant rate of manufacture to 2019.

Wind would be scaled up faster because it is cheaper and there are already a number of installations in the pipeline. New projects would start every six months and take a year to complete. A three-year ramp-up should lower the cost to European levels, also followed by a constant rate of construction.

What resources are required?

The Plan involves building 23,000 km of high voltage transmission – both to connect the new power stations to the grid, and to connect the multiple existing grids to each other (so supply does not depend on the weather in one place).

At peak construction, the Plan requires 600,000 heliostats and 1,000 wind turbines per year. These could either be mass-produced in Australia or imported. In Australia it could create 30,000 jobs in manufacturing.

The plan would also create 80,000 new construction-related jobs, and 45,000 ongoing jobs in operation and maintenance, replacing an equivalent 20,000 in fossil fuels. In addition, the 30,000 manufacturing jobs could also be retained to export components to the world. Some solar jobs would even be in the same areas as lost mining jobs.

The concrete needed is a tiny fraction of Australia’s resources, and the steel a tiny fraction of our exports. A solar power plant uses merely 12% as much water as a coal power plant. However, we would need several new factories producing glass and other materials.

How much will it cost?

The total capital cost over the decade is $370 billion, or 3% of GDP per year. That’s about the amount of money spent on insurance, or the value added by the real estate sector, or the money spent on coal, gas and uranium. Most of the money is spent in the latter half of the decade, after the public has already seen some of the benefits of the initial investment.

About half of the money, $175 billion, would be spent on solar thermal plants, as well as $92 billion to upgrade the grid, $72 billion on wind turbines, $17 billion on off-grid solar, and $14 billion on biomass. However, the Plan looks at these costs as an investment. It leaves open the question of where the funding would come from, suggesting a combination of public and private sources.

The investment pays itself back by 2040 or as soon as 2022, depending on which costs you count. The Net Present Cost over the period 2011-2040 is equal to business-as-usual (BAU) if you only include direct costs. Though the capital costs of ZCA2020 are much higher than BAU, more money is saved because solar power plants do not need a constant supply of coal and gas for fuel. If you also take into account the Net Present Cost of oil and (possibly) priced emissions under BAU, ZCA2020 could potentially save $1.5 trillion.

Economic Model Comparison

Figure 4: Net present value of ZCA2020 Plan compared to business as usual.

All the above completely ignores climate and environmental costs, which obviously would heavily favor ZCA2020. The Stern Review estimated that a global effort to mitigate climate change could save 20% of GDP per year by 2050.

The effect of the transition on electricity prices depends on how it is funded. In one possible scenario, they could rise by $8 per household per week, similar to what is expected under BAU.

What will happen to the fossil fuel industry?

The report does not address this as it is a political question. However, it does point out companies were aware of the risk to their industry when they invested in their assets.

How do we convince our leaders this is a good idea?

Now I wish I knew the answer to that one. When Australia (and the world) finally wakes up to the climate crisis, Zero Carbon Australia 2020 provides a useful blueprint for decarbonising our energy sector. But we’d better wake up pretty damn quick.

Societies have shown that they can be mobilized by ambitious visions. When J.F.K. proposed landing a man on the Moon before the end of the 1960s, it seemed incredible. Yet the goal was accomplished twice before the deadline.

So far Australia has not shown leadership on clean energy, preferring to see itself as a mining nation. Renewable energy entrepreneurs are going overseas because there is no market in Australia. Yet we have vast untapped renewable resources.

Global warming is a very real and urgent threat. As an extremely high per capita emitter Australia has an imperative to take drastic mitigating action. ZCA2020 shows powering Australia with renewable energy is feasible using commercially available technology. Solar thermal can provide better-than-baseload power. The transition would stimulate the economy, save up to $1.5 trillion by 2040, create jobs, and make Australia a leader in clean energy. So what are we waiting for?

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Comments 51 to 100 out of 120:

  1. MattJ#19 : In #3, I just gave some facts and asked some questions - so I don't know which "claims" you're talking of.

    Concerning Iceland, this is the most recent news I heard from "hydrogen economy"
    http://www.eenews.net/public/climatewire/2009/07/01/1

    That's interesting, because my claim is that modern economies is possible only with cheap and convenient energy. So "alternatives" are not really interesting if they're neither cheap, nor convenient. A corollary is that when cheap and convenient energies (and despite their drawbacks, FF ARE cheap and convenient) will exhaust, economy will sink - and it just happened that some years after the peak of conventional oil , the barrel went up to the stratosphere, and western economy plunged into the deepest recession since the war -including Iceland, Denmark , and Spain, despite their high level of renewable electricity - which didn't help them at all to resist the economic tsunami. So for the moment, I just considering facts , and facts support my claims.
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  2. Ken #40 - the report suggests combining solar thermal with biomass burning. You can use much of the same infrastructure, and then you can still provide power during long periods without sunshine.
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  3. idunno@49

    It is common practice now to work out life cycle emissions as grammes of CO2 per kilowatt hour. These figures include materials used, manufacture, installation and decommissioning.

    Whether a fan or not, the world nuclear association has compiled quite a good list of research papers that analyse the CO2 footprints of different energy sources:

    http://www.world-nuclear.org/info/inf11.html

    Regarding wind turbines. The pad is largely concrete and then the tower is prefab steel bolted to it. On top of that is the nacelle/generator and blades.

    Tidal turbine farms are probably about 10 years behind wind in development, so the first small scale installations are just being planned/constructed.

    A 10 turbine farm has been approved this week in Scotland:

    http://www.independent.co.uk/environment/green-living/tides-to-power-whisky-distilleries-2245207.html
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  4. Interesting new development in vanadium redox flow batteries:

    http://www.sciencedaily.com/releases/2011/03/110317141418.htm
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  5. "CBDunkerson at 04:30 AM on 21 March, 2011
    ranyl #46, keep in mind that the current CO2 level is 'artificially inflated' in the sense that it represents an overflow rather than equilibrium value. Basically, about half the CO2 we emit each year is currently being sequestered (mostly in the oceans). If we were to drop to zero emissions that sequestration would continue and the atmospheric concentration would start dropping... probably at a rate of about 2 ppm per year.

    Thus, even if we hit 450 ppm before zero emissions goes into effect, we would not stay at that level once emissions stopped.

    As to 2C vs 3-5C... the difference is between fast feedbacks and slow feedbacks. A doubling of CO2 (about 560 ppm) will likely cause about 3C warming from fast feedbacks (i.e. within a few decades), but more likely around 6C when slow feedbacks (i.e. within a couple of centuries) are considered. However, both of those would require that the atmospheric CO2 level remain elevated... which it would not if our emissions drop significantly below the rate at which atmospheric CO2 can be sequestered."


    Yet others have found on the subject of the removal of CO2 from the atmosphere that,

    “not only does anthropogenic CO2 in the atmosphere need to be removed, but anthropogenic CO2 stored in the ocean and land needs to be removed as well....meaning an additional amount of CO2 equal to the original CO2 captured would need to be removed”
    Long Cao and Ken Caldeira
    Env. Res. Lett, 5 (2010) 024011 (6pp)
    http://iopscience.iop.org/1748-9326/5/2/024011?fromSearchPage=true

    Dunford (Science May 2007), showed southern Ocean sink now releasing CO2. (Park Geo.Res.Lett. 2008), showed 50% Reduction of sink of coast of Japan, (Schuster Oct 2007 J. of Geo. Res), Ocean sink 50% reduced N.Atlantic.

    Lowe (Env.Res.Let 2009, http://iopscience.iop.org/1748-9326/4/1/014012?fromSearchPage=true), seems to suggest that CO2 levels even with adrupt stops take a long time to come and at a slow rate,"HadCM3LC simulates very low rates of decline in atmospheric CO2 concentration. Mean (regressed) rates of change for the following hundred years are predicted as –0.2 ppm y–1, –0.4 ppm y–1 and –0.75 ppm y–1," an order of magnitude lower that the 2ppm a year rate suggested, and not taking into account the release of CO2 from a warming atmosphere due to permafrost melt, the general relationship that a warming trend causes a release of CO2 nor CO2e which is already at 460ppm, so really getting to 350ppm is a lot of carbon removal.

    Do realise that the 3-5C is the long term equilibrium sensitivity equivalent and that in 100years you get about 60% of the full equilibrium level temperature change.

    That suggests that if the Pliocene CO2 levels were ~350ppm, then the earth should heat up 60% of the way to 3-5C by 2100, so 1.8-2.4C, if CO2 levels were ~400ppm in the Pliocene then the earth should rise at least 1C to 1.78ppm at 350ppm but 1.8-2.4C at 400ppm.

    There is enough uncertainity in this paleoclimatological records to create an endless debate, however considering the ever growing evidence for a higher CS than 3C and the risks involved of too much CO2 maybe 350ppm asap induced by a massive CO2 withdrawn due to man's activties is a pragmatic approach.

    What carbon peak is safe?
    (considering that unless CO2 is actively withdrawn it will stay at that level for a long time and CO2e levels)

    400ppm means removing 50ppm and more from the atmosphere to get to 350ppm.

    That is a considerable amount of carbon so is there potential for bioshpere enhancement to draw down that much CO2?

    If 400ppm is a peak that leaves a very tight budget to replace a whole enery, transport, farming, health, economic and building systems (which are all fossil dependent) to being fossil independent and CO2 sequestering and there are also adaptation needs and the ever increasing population demands.

    Is such a large challenge of human adaptive ingenuity even worth considering?

    How quickly can human activity become carbon negative and biosphere enhancing with a best effort from all concerned parties?
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  6. Figure 1 in the article shows global per capita emissions budget assuming constant annual emissions. Does this budget also assume constant population and nil growth in size of national economies?
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  7. Let’s have a reality check here!

    In theory, solar concentration technology (SCT) could replace coal and other fossil fuels as the source of Australian electricity production but that has not happened, is not contemplated and is unlikely to occur. We should ask ourselves why.

    Electricity consumers are happy to buy their electricity needs from any source, with one important proviso - that it is the cheapest energy available. SCT simply does not produce this. In fact it is the most expensive of all renewable energy sources and can only be made competitive with coal (the cheapest energy source) if the price of coal doubles through imposition of a carbon tax.

    In short, SCT is not competitive with coal or any other renewable energy source and, in the absence of electricity storage capacity, wind is over-rated as a source of base load power. That is not to say that wind does not make a useful, if limited contribution to reducing dependence on coal.

    When solar technology becomes more efficient (it will) it will become the technology of choice to produce most of the world’s energy needs. But to think that countries now reliant on coal to generate electricity will turn to SCT is wishful thinking. Why would any country opt for a much more expensive SCT product? Try convincing the top 5 emitters (China, USA, India, Japan, Russia) responsible for >55% of global CO2 emissions, that they should replace coal with solar.

    Australia is uniquely placed in that it has the most extensive hottest granite at the shallowest depth found anywhere in the world. Contrary to the view expressed in the article, geothermal technology is now well developed and understood. The first commercial power house is expected to be up and running by 2015. Ref: Geodynamics Annual Report at:
    http://www.geodynamics.com.au/IRM/Company/ShowPage.aspx?CPID=2277&EID=11787609

    Estimates vary as to the capacity of geothermal to meet all of Australia’s expanding need for base load power but what is clear is that production per MWh is the cheapest of any renewable source other than wind. It can produce reliable base load power, is emission-free and billions are being invested in it in a bid to ensure that, in the short-medium term, it reduces dependence on coal.

    Any contest between solar and geothermal for the supply of Australia’s electricity needs will be won by the latter on price – at present. However, there is ample scope for R&D into more efficient use of solar energy to generate electricity and this is where resources are needed.

    One would hope that this would result in the development of much more efficient PVC’s, and much improved methods of storing heat and electricity. Only with such developments over the next 10-20 years will solar become a real competitor with wind, wave and geothermal – and the preferred alternative by nations currently dependent on fossil fuels.
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  8. Ken Lambert, to the best of my knowledge, coal fired power stations in Queensland haven't exactly fared too well in the floods either. 85% of Queensland's Coal Mines were left operating at *well* below normal capacity-with most of them being completely shut down. Rail links between coal mines & coal stations were washed out by the flooding, & at least 2 of the coal power stations apparently had operating difficulties due to flood waters. All of which led to a huge amount of load shedding during the flood crisis-not to mention the towns which were completely cut off from their electricity supply by the flood waters. So you see, Ken, your desire to focus on the impacts of extreme weather events on renewable energy ignores the fact that these extreme weather effects have a similarly negative impact on so-called conventional sources of electricity. Also, can you provide *proof*, Ken, that wind resources in Queensland dropped during the flood crisis? My understanding was that the low pressure system that brought in that rain was also associated with above average winds-but maybe I heard incorrectly.
    Lastly, its worth noting that during another extreme weather event-namely the Victorian Bushfires of 2009-large areas lost their coal-fired electricity because of ash & smoke shorting out the high voltage lines. However, many of these homes would have *still* had electricity if they'd all had grid interactive solar panels.
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  9. From my reading on Wind Turbines, the life-time CO2 footprint is around 5g CO2/kw-h, & a Wind Turbine has an energy pay-back time of about 20 months, & will return more than 30 times the energy investment over its lifetime.
    Like I said above, though, this assumes current methods of steel & concrete manufacture are used-but there are relatively new methods that have a much lower carbon footprint. Also, that energy pay-back time & life-time CO2 footprint can be made even lower if energy storage-particularly Vanadium Redox Batteries, electrolysis or regular batteries-is also used, as this will double the capacity factor of a wind farm.
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  10. Agnostic - first I'm inclined to agree that SCT is coming tech not here. I would note though that PV is a lot more expensive than SCT so it's hardly the most expensive of renewables. The various marine options are even more expensive now. Will it change quickly? SCT costs are almost all in the construction. When every station is a custom build, then parts will be very expensive. On the other hand, I dont think we need major new technology to change that equation.
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  11. @scaddenp: "I dont think we need major new technology to change that equation"

    That's exactly right!

    If you've read the ZCA report (as I have), you'll note that they state up-front that that was one of their 'design constraints' - that no major new technology is required.

    What this also means (and something that a lot of people overlook) is that the ZCA report specifically *excludes* any technology that will be viable in even 15-20 years. The objective of their plan is, after all, to be zero-carbon in just 10 years.
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  12. Wow The Ville, that's some fantastic news. I mean, I knew VRB's were already pretty good under *most* conditions, but these recent improvements should really open the gateway to more widespread use of VRB's for wind power storage.
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  13. Hmm, those VRBs do look good. I imagine the storage capacity is determined by the storage tank volume?

    What's the cost look like? Affordable enough to store many MegaWatthours of electricity?
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  14. How long would it take to construct and install the required quantity of wind generators and solar energy power stations, PV panels. etc? Presumably it would be quicker than the 10 - 15 years for nuclear, but are there any calculations to hand? I guess if the government was serious it would crank up an industry (convert one of the car plants) to churn them out like Spitfires were during the war.
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  15. OK Bern. According to a deal signed by the builders of the Sorne Hill Wind Farm in Ireland, a 12MWh VRB's was going to cost just under $6.3 million-back in 2007. Of course that's with the older technology. In 2009, German Scientists claimed that they managed to boost the energy density of the VRB's from around 30Wh/L of electrolyte to 150Wh/L of electrolyte-which would substantially reduce the cost of new VRB's. The advances linked to by The Ville will almost certainly bring the price down further still. Of course the important thing is that it would effectively double the capacity factor of the 30MW Wind farm to which its attached.
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  16. ranyl #55, there is no contradiction between the passages you cite and what I had stated. The 2 ppm drop per year which I calculated would not continue on the century scale examined by the Lowe paper. That is, if we stopped emitting CO2 today we would not drop 200 ppm and find ourselves at the coldest point of a glaciation (190 ppm atmospheric CO2) by 2111.

    Currently we are releasing about 30 gigatons of CO2 into the atmosphere each year and carbon sinks are extracting a net of about 17 gigatons. Each additional 7.81 gigatons in the atmosphere corresponds to another 1 ppm. Thus, atmospheric concentration is currently growing at about (30 - 17) / 7.81 = 1.66 ppm per year.

    If our CO2 emissions dropped to zero the carbon sinks would continue sequestering about 17 gigatons per year (17/7.81 = 2.18 ppm decrease per year)... there is no logical reason that this would change radically right away. However, this amount would decline on a decadal scale as atmospheric and oceanic concentrations approached equilibrium. The prior equilibrium was at ~280 ppm so we would certainly hit zero decrease some time before that point... exactly when depending largely on the rate at which carbonic acid will mix throughout the world's oceans.

    Note that some of the values you cite from Lowe involve unfettered CO2 emissions through 2050 or 2100... resulting in vastly higher atmospheric levels and potential oceanic saturation. The -0.2 ppm figure based on 404 ppm in 2012 was again looking at the mean over a century... so by 2112 we'd have dropped to 384 ppm. I think (and other papers such as Meehl 2007, Plattner 2008, and Solomon 2009 cited in the Lowe paper seem to agree) that the equilibrium point would likely be much lower.

    In any case, Lowe agrees that there would be a quick drop after cessation of emissions and then a very long slow decline. Only how far the initial drop would be is in question. However, as I'd stated... hitting 450 ppm does not mean we are stuck there. It is only if we go significantly over that mark or continue significant emissions even after converting to alternative energy sources that we need to worry about the long term impacts of 450 ppm (or any other level) atmospheric CO2. Stopping emissions will yield positive results / we are not yet 'locked in' to devastating climate change.
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  17. John Chapman - using currently disused car factories for heliostat manufacture is, in fact, suggested in the ZCA report, if I recall correctly.

    As for the rest of it - a quick search reveals the 750MW Kogan Creek power station (750MW coal) took about 3.5 years from a "go" decision to full commercial operation. A "first of a kind" solar thermal unit would obviously take a bit longer, but probably not too much, as all the required technologies are off-the-shelf.

    The problem is where to get the funding? It'd probably have to be a government-backed project, at least for the first one (to "prove" the product to the market, given how risk-averse investors can be in Oz).

    I did some more quick sums.
    ZCA estimates ~$739m or so for a 217MW plant.
    The Kogan Crk coal plant cost $1,200m for 750MW, but burns 2.8million tons of coal per year (for which it's probably paying minimal royalties plus the cost of digging it out of the ground at the adjacent mine). Assuming it cost about $40/t (about a third of the market rate for good quality thermal coal), that's another $112m per year for coal.

    Doing the sums, it takes ~3.5 of ZCA's solar towers to equal Kogan Creek. So that's $1.2billion vs $2.59billion in up-front cost. If you assume operation & maintenance costs are a wash, and when you add in the cost of the coal (ignoring inflation), it takes 12 years for the total cost of the coal plant to equal the solar tower. But over a nominal 30-year life, the solar towers end up ~$2billion cheaper - almost enough to pay for the solar towers in the first place!

    Factor in a $20/t price on CO2, and the price difference increases to ~$6.2billion (assuming 2.5t CO2 / 1.0t coal) i.e. enough to pay you back for the initial 3.5 solar towers, and build another five to cope for future demand!

    Now, discounting of future coal prices makes a big difference (how much is $112m/year for 30 years worth today?), but the cost equation will probably still favour the ZCA proposal, based on their numbers, especially when a carbon tax is thrown into the mix.

    If you count the benefit of avoiding ~200 million tons of extra CO2 in the atmosphere, then things really start to look positive...
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  18. Marcus #58

    I did not hear of any power blackouts during the flood crisis in Queensland due to unavailability of coal fired plant.

    Last time I checked, wind energy generated through an axial turbine was proportional to the wind speed cubed.
    If a turbine is optimized for a wind speed of say 20 knots, when the wind blows at 10 knots you get 1/8th of the power from the unit. If it blows at 30 knots you have to feather the blades and shut the unit down.

    The average availability of coal fired plant is over 90% - ie; the output/installed capacity.

    For Wind it is below 30% and I have seen numbers in Victoria which suggest at low as 12%. That means you have to install 3MW+ of Wind capacity to get an average of 1MW output. I trust is taken into account in all Wind power comparisons with coal, nuclear & geothermal.

    Again in Australia, particularly in winter - a large slow moving high pressure system can reduce wind speeds to below 5 knots for a day or two over large areas of the continent, and strong cold fronts between can cause shutdown due to excessive wind speed.

    Wind therefore needs significant back-up capacity or storage capacity when it does not blow over a wide area.

    BERN #67

    Where can I invest in your ZCA systems?....readers must be knocking down your door to do so..on your numbers.

    One question - do 3.5 of your ZCA's have the same availability as 1 x Kogan Creek?
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  19. New battery cathode technology, promises very short charging times for current battery technologies (NiMH and Li-ion):

    http://www.sciencedaily.com/releases/2011/03/110320164225.htm
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  20. "If our CO2 emissions dropped to zero the carbon sinks would continue sequestering about 17 gigatons per year (17/7.81 = 2.18 ppm decrease per year)... there is no logical reason that this would change radically right away"

    CBD66

    These acute excess sinks don't continue to take CO2 out of the atmosphere, they take ~50% of the extra excess CO2 added to the atmosphere be that from volcanoes, land use change or human burning of fossil fuels, but that is it, they soak up the excess, they don't actively remove carbon atmosphere if no excess is added. Basically with no emissions at all the rate of CO2 change in the atmopshere reverts back to the underlying balance between volcanic source and geological removal which is very slow.

    Then as this very slow (no where near 2ppm at year) causes atmospheric CO2 concentration to fall the sinks re-release the 50% of the excess they took up and why Cao et al (from previous post), found that to get CO2 concentrations to actually fall it is necessary to take all the extra CO2 that was actually added to the atmosphere and the CO2 that has been temporarily stored in the acute excess sinks.

    Also all the excess sinks capacity are now shrinking as per the papers in the previous post.

    Therefore 450ppm peak does mean ~450ppm for a long time unless active measures can be deployed to remove CO2 from the atmosphere. Also as mentioned when the earth warms CO2 always rises at about 7-40ppm per 1C, depending on different estimates although 7-14ppm most likely, but still rises and there is already another 0.6C to come due to lags in the system.

    Also the Pliocene was still 3-5C hotter at 350ppm or 1.8C-2.4C by 2100, 450ppm means more!

    Also all the pollution over China and India is causing a large haze cloud that is cooling those regions surface, therefore stopping burning fossil fuels in Asia will be another accelerant to global warming.

    "Stopping emissions will yield positive results / we are not yet 'locked in' to devastating climate change."

    Yes stopping all emissions from fossil fuels is essential and a strong positive first step, but the world is already locked into a significant period of global warming that needs urgent adaptation (including removing large quantities of CO2 from the atmosphere) measures so that despite the coming climatic changes human actions can bring about a fullfilling sustainable eco-system enhancing carbon sequestering future and a general increase in human well being through mutual co-operation, at governmental, institutional and individual levels or the clear and obvious is ignored, CO2 emissions continue to be spent chasing excessive energy demand dreams and humankind lets climate change be an event that is devastating to human well being for no other reason than keeping far too many lights on.
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  21. Ah Ken, good to see you preaching from the same hymn-book as Gilles. It might not have made headline news (you know, what with all the property damage, deaths & evacuations), but news of load shedding & black-outs during the Queensland floods can be found in the print media *if* you're prepared to go digging. The closure of many of Queensland's coal mine during the crisis was, however, considered worthy of front-page news. Of course my whole point was to illustrate that, in such extreme weather events as these, loss of power is going to be the *last* thing on victim's minds-so represents nothing but a straw-man argument. It is worth noting, though, that the large, centralized nature of coal power station, as well as their reliance on a constant fuel supply that needs to be mined, does make it especially vulnerable to extreme events like these. Even in the absence of such events, coal power stations are horribly inflexible in their power output & lose significant amounts of generated electricity over the distances they're required to transmit over (between 10%-15% of electricity generated gets lost during Transmission & Distribution).
    Your claims re: Wind Turbines also sounds horribly out of date. My reading of current technology is that most modern wind turbines are designed to operate effectively under a wide range of wind conditions-something which has allowed improvements in Capacity from barely 20% to more than 30% in the last decade. Of course, with good siting & decent storage, many of the remaining issues with wind power can be largely iron out-and eliminated completely if you also have a good source of landfill gas.
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  22. Ken Lambert:
    "I trust is taken into account in all Wind power comparisons with coal, nuclear & geothermal."

    Despite the relatively low load factors for wind turbines, the energy payback is usually as good as or better than other sources.

    If you look at life time data:
    http://www.world-nuclear.org/info/inf11.html

    then you see that the worst case input energy for wind turbines is 16.7% of total energy output, the best case is just 1.3%.
    For coal, the worst case is 14% and the best is 2.9%
    For gas, the worst is 17.9% the best is 3.8%

    It should be pointed out that most nuclear power stations are just as inefficient as fossil fuel power stations, the efficiency is some 30% to 40%. The issue is even worse for coal since most of the embedded energy is wasted.
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  23. ranyl @ 70: Sorry, no, you're not quite right.

    The natural sinks of CO2 don't care about where the CO2 is coming from - all they care about is the atmospheric concentration.

    If atmospheric concentrations of CO2 are higher than the equilibrium point, the sinks absorb more of it. Period.

    So CBDunkerson's comment that the sinks would continue to absorb 17 gigatons per year is correct.

    You seem to have missed the point, though, that this rate is by no means constant - it will decrease as the atmospheric concentration decreases, and will logarithmically approach equilibrium (i.e. it will take centuries to get there).

    You are correct, though, that some current sinks will turn to sources - e.g. as atmospheric levels drop, CO2 dissolved in the oceans will start to come back out. This is one of the factors that greatly extends the time to reach equilibrium, especially as the oceans seem to be absorbing the vast majority of human emissions.
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  24. As impressive as the Solar Power Tower is, I reckon we should go for Big Dish technology-which uses a sterling engine to create electricity directly. As far as I'm aware, it can also be coupled with a secondary system through which you can run chemicals for heat dissociation.
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  25. ranyl, as Bern explains, there is no mechanism for carbon sinks to respond directly to CO2 emissions from human industry. The absorption rate of natural carbon sinks is instead driven by the total atmospheric CO2 level.

    Think of it as an osmotic process... the higher the imbalance between atmospheric and (for instance) oceanic carbon concentration the faster the net transfer of carbon between the two. As the two approach equilibrium the transfer rate slows.

    It gets complicated in this case because the carbon content of the ocean surface is currently much higher than that of the deep ocean... we have been adding carbon to the atmosphere, and thus indirectly to the ocean, more quickly than it can disperse throughout the total volume of ocean water. Thus, if emissions were to stop we would first hit an equilibrium between atmospheric and ocean surface carbon and then very slowly drift towards a lower equilibrium point as the ocean surface concentration (and hence atmospheric concentration) decreased as the carbon disperses through deeper water.

    In short, the carbon we have emitted thus far locks us into to atmospheric CO2 levels higher than the previously semi-stable level of about 280 ppm for tens of thousands of years... but if we stopped emitting we would see a significant drop in atmospheric levels in the short term followed by a long slow decline. It is the level at the start of the slow decline which we need to worry about as that will be what we are 'stuck with' on timescales long enough for all feedbacks to come into play.
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  26. Marcus #71

    It seems that I am 'horribly' wrong all over the park Marcus. It only that were true.

    "It is worth noting, though, that the large, centralized nature of coal power station, as well as their reliance on a constant fuel supply that needs to be mined, does make it especially vulnerable to extreme events like these."

    Quite the opposite Marcus. Coal fired plant sited on mine sites find coal storage pretty easy and cheap. It is not hard to store many days supply of coal to keep the plant running in a mine shutdown. Coal fired plant sited on rail links can get coal from other mines or interstate.

    "Even in the absence of such events, coal power stations are horribly inflexible in their power output & lose significant amounts of generated electricity over the distances they're required to transmit over (between 10%-15% of electricity generated gets lost during Transmission & Distribution)."

    Quite the opposite again Marcus. Coal plant can be run up from cold in a matter of hours and spinning reserve brought
    on-line in minutes. Multiple generator sets are used to match load to capacity to achieve optimum efficiency and the flexibility required of base load plant. Peak demand can be handled with systems like pumped storage hydro and gas turbines.

    The issue of distribution losses is not related to the method of powering the generators. It is a function of voltage level and distance from major loads. The same line losses would apply to Bern's ZCA systems.

    "Wind Turbines also sounds horribly out of date. My reading of current technology is that most modern wind turbines are designed to operate effectively under a wide range of wind conditions-something which has allowed improvements in Capacity from barely 20% to more than 30% in the last decade. Of course, with good siting & decent storage, many of the remaining issues with wind power can be largely iron out-and eliminated completely if you also have a good source of landfill gas."

    The blade designs are more effective at widening the range of operating wind speeds, however they are still subject to the power output being proportional to the cube of the wind speed. Only the best sites produce 30% availability.

    Ideal sites are those with high steady winds near the optimum speed for the turbine. The best are very tall and at sea.

    Building 1000 turbines per year on land needs something like 300m each of space for a 3MW nominal unit. End on end - you would need 300km.

    A 3MW turbine has a 90-100m blade diameter on a 100m high tower.

    At a best 30% availability, one of these 3MW units will only produce an average of 1MW over a year.

    To replace 1 x Kogan Creek 750MW plant, one would need 750 of these turbines. They would stretch end on end for 225km.

    People are affected adversely by the low freguency sound pressure levels caused by the blade disturbance - not to mention the danger to the orange breasted parrot.

    And you still have the extra costs of storage of energy and distance from loads for such widely dispersed units.

    And of course you say all will be fine if you have a landfill nearby each wind farm with enough biogas (and gas turbine or engine) to smooth out the 5 knot clear winter days when you only get 3.5% of nominal power out of each unit.

    Hello??
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  27. Hi CDB and BERN,

    Yes agree and did have a misconception of the lag involved to equilibrium and why I felt that there wouldn't be much of immediate a drop of CO2 even if all emissions stop and must still say not convinced there will be as many of models make many questionable assumptions especially about the terrestrial sinks.

    But how much of a drop will there be before equilibrium is reached as the sinks do seem to be falling and every other time the globe warms CO2 overall is released?

    Also there is all the frozen lands to thaw and release CO2 and when past equilibrium point the CO2 put acutely into the sinks over the last 100years or so will be released before CO2 falls further..

    So even we stopped today, 390ppm, where is the equilibrium point, if 75% overall equilibrium removal is right that is about 335ppm, but that takes several 100years to acheive meaning we'll still be above 350ppm until 2100 and that is presuming no decline in the sinks which is unlikely as world still warms for 1000's years, meaning the oceans warm, permafrost melts etc...450ppm and we'll still be the high 300'slow 400's by 2100, as it will take 25 years to get to 450ppm at the present rate.

    And do agree entirely that having zedro emissions for activities is essential, however also feel that to get to safe levels a large draw down of CO2 is necessary, even at 350ppm the pliocene is calling eventually but to avoid 2C by 2100 we need to be at most 350ppm by then.

    We are 40ppm above 350ppm already and the chance of stopping emissions abruptly about the same as a snowball in a hot place, so what do we plan for?

    >2C or below and isn't even 1.5C going to be a major task of adaptation considering what is already happening?

    There really is no carbon budget, the debt is already in the bank, however to adapt we need to make the smallest extra withdrawal we can, so how much is that?

    400ppm peak? That is 5 years away!!!!!
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  28. ranyl #77, "But how much of a drop will there be before equilibrium is reached"

    That is the question and I don't pretend to know the answer. The Lowe paper finds that we would reach equilibrium with very little reduction in atmospheric CO2 levels, but itself notes several other studies which suggested more significant drops.

    Whether we will see significant carbon release from long term environmental sinks (e.g. permafrost, mathane clathrates) is still an open question. Obviously that could be very bad... potentially keeping GHG levels elevated regardless of whether we cut back/eliminate emissions from industry.

    There is definitely a great deal of cause for concern, but we can't pin down the effects of current levels and plausible reduction scenarios any more precisely than somewhere between 'somewhat inconvenient' and 'massively destructive'. Of course, if we don't bother reducing emissions at all that'll be another story.
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  29. "Of course, if we don't bother reducing emissions at all that'll be another story."

    Very true and there globally there hasn't exactly been much progress so far despite all the efforts, as all the savings have been swamped by the ever increasing demand.

    Not sure what it will take, but in the mean time adaptation planning (mitigation and adaptation in the wider context (adapting to be fossil fuel independent)) seems a sensible stance.
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  30. Ken Lambert at 00:59 AM, regarding the coal supply to power stations, there is a requirement for power stations to maintain a minimum stockpile of coal, something like at least a months supply to cover supply disruptions depending on the supply chain.
    The operators are not stupid and fully understand the realities of coal supply logistics in the real world, especially seasonal risks when force majeure is most likely and plan accordingly.
    The only sin considered greater than a power station running out of fuel is for an aircraft to do so.
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  31. Firstly, I dont buy that we need to go to zero. We just have reduce one hell of a lot (but then I work in oil/coal so maybe that is rationalization). Hard to see how we drop coal for steel-making.

    Second, I was impressed by the range of fuel options for liquid fuels detailed by cudby in from smoke to mirrors for those applications that have to have them.

    Will they be as cheap as FF. Nope, but then who thinks climate change will be free?
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  32. "It seems that I am 'horribly' wrong all over the park Marcus. It only that were true."

    Yes, you *are* horribly wrong Ken-& still are-but that's what happens when you rely on Coal Industry propaganda & not actual *facts*.

    Do you deny the press reports about 85% of Queensland's Coal mines being partially or completely flooded? Do you honestly believe that won't have-or hasn't already-had impact on supply?

    Also, if Coal Power stations are *so* flexible, then why do we get constant load shedding in Summer? Why do the plants operate at close to 100% capacity 24/7, when off-peak demand is barely *half* of that during the day? They'd hardly waste the fuel, so I'd guess its because they *can't* turn down the power to match supply.

    As to Transmission & Distribution losses, in spite of your claims this has everything to do with *distance*-the longer the distance between energy supply & energy demand, the greater the losses in electricity along the line. Distributed Generation is the only way to reduce-or eliminate-these losses, but inflexible coal power stations don't fit into a distributed generation framework very well.

    I've read far & wide on Wind-Farms, & your comments continue to display your ignorance regarding them. A 3MW Wind Turbine, operating at 30% Capacity Factor, will actually generate 8,000MW-h per year. Of course, without storage, some of the excess capacity-especially at night-will either go to waste or won't be harvested (i.e., excess capacity will get shut down). This is why VRB's have proven so successful at raising Wind Farm Capacity factors-to as high as 60% to 70%. Again, from my reading, current capacity factors are between 20% to 40%, with most modern Wind-farms achieving 30%-35% (without storage)-your ignorance of these facts doesn't make them any less real.
    Your talk of the negative health impacts of "Infrasound" merely prove that you spend way too much time reading The Australian for your information-a well known, anti-renewable newspaper. There is absolutely *no* medical basis for this so-called "disease", & its extremely odd that no one who actually has the wind farms *on* their properties (& are thus being *paid* for the use of their land) has actually been effected by Infransound-only those who live several kilometers away & object to the view. I wonder how they'd feel living near a coal power station & its associated, open-pit coal mine?
    Your claims about the distance taken up by a wind farm are equally facetious. Are you going to tell me that Coal Power stations, & their associated mines, don't take up land? Yet, unlike Coal Power stations, land with wind turbines on them are still able to be used for other purposes.
    Lastly, though your concern for endangered birds is....touching, its not a very good reason to oppose wind farms. Modern Wind Farms actually have very little negative impact on bird populations &-in fact-its been shown that the negative environmental impacts of the mining & burning of coal do *far* more damage to bird populations (per MW-h of electricity generated) than wind turbines. You know, what with all the land degradation & the harmful emissions from the power station-as well as the looming impacts of climate change. Seriously, Ken, I think you need to read a little more widely than the brochures handed out by WMC, BHP & Rio-Tinto.
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  33. Well, it feels very strange going into bat for Ken, but...

    "Also, if Coal Power stations are *so* flexible, then why do we get constant load shedding in Summer?"

    I'm not entirely sure what you mean, but station efficiency and generation capacity is dependent also their ability to reject heat to cool steam. This most certainly has a seasonal influence.

    " Why do the plants operate at close to 100% capacity 24/7, when off-peak demand is barely *half* of that during the day? They'd hardly waste the fuel, so I'd guess its because they *can't* turn down the power to match supply."

    I think you need to have some pretty complete figures on demand and production. Stations most certainly CAN turn down the power to match demand. You get efficiency losses (effectively useful heat that isnt being converted) as station comes off load, but they can certainly come down (and up) fast.

    I'm not that familiar with overall Australian generation system, but I would expect hydro to be used when possible, BIG coal to provide base load, and "others" to balance demand.

    Do I know anything about coal power stations? Well I am programme leader for this project and I've looked at a live data from quite a few Australian power stations.
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  34. scaddenp. During Summer, peak demand for power frequently increases, & this leads to load shedding-this is usually reported in the press as an inability for the base-load power stations to ramp up supply.

    "You get efficiency losses (effectively useful heat that isnt being converted) as station comes off load, but they can certainly come down (and up) fast."

    Yes, but the key point is the efficiency losses-this does limit its flexibility. Most renewable energy power stations can adjust their output *without* those same efficiency losses. Of course, coal power stations aren't very efficient to begin with-with only 35% of the heat from the coal being used to create steam. Personally, I think gas (be it natural gas or methane from decomposition of organic material) is much better-as even a conventional Gas Turbine gets 60% thermal efficiency-with a Combined Cycle Gas Turbine getting as much as 80%.
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  35. If cooling is impaired, then that limits output. No contradiction here.

    Efficiency losses on ramp-down arent that great. They do work much more efficiently at constant load agreed, but then you do need base-load.

    80% for CCGT?? 60% is outstanding. Got a link for someone claiming 80%? I also dont believe a single cycle turbine has ever hit 60%.

    However, for all that defense, I think moving away from coal power is highly desirable. They are inefficient, coal is dirty industry, and we cant afford the climate cost. That is reason enough. No need to gild the argument with spurious other factors.
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  36. Ken Lambert: if you invested your hard-earned on the basis of my back-of-the-envelope calculations, then I've got a nice bridge I'd like to sell you... :-P

    My point wasn't to do a detailed cost-benefit analysis, but to throw out some numbers for consideration.

    Yes, those numbers likely to be wildly inaccurate, but even if I was out by a factor of three, then going solar thermal has a long-term break even point, compared to coal - while totally ignoring the climate change costs associated with continuing coal use (which *will* be measured in $trillions, and in the absolute worst case, could cost 100% of world GDP - i.e. complete breakdown of global economies)
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  37. ( - numerous rantings violating the Comments Policy en masse snipped- )
    0 0
    Moderator Response: [DB] Posting on this site is a privilege, not a right. Future postings such as this one may have that privilege rescinded. Be advised.
  38. I think that this as a fantastic idea and I am right behind it. I do however need one last bit of convincing that it is possible. A final tick of approval for the plan if you will. Where are you going to get the raw materials, more specifically the rare earths. For every MW of wind electricity generated you require 1 ton of Neodymium. 90% of this mineral is mined in China and due to its advanced renewable energy projects they are not sharing anymore. Australia mine no neodymium until the mines at Mt Weld and Nolans bore are up to speed. Even then they will not produce enough. The whole world produces about 28,000 tons of this element a year (hence the term rare earth I guess). We would need a significant portion of the worlds supply to achieve these targets and even then there is the not sharing anymore issue. That is just one element. Add to the list Lanthanum and Yttrium and a host of others used in solar and reflective glass and electricity storage. Should we be fighting against the Greens and fast tracking rare earth mining project? Will we have enough?
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  39. Vague #88

    Please expand on the role of rare earths in Wind and Solar collectors??
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  40. Ken,

    Some of the most efficient & powerful wind turbines use rare-earth permanent magnets in their generators, which can generally be made smaller & lighter that way (an important property for something you're sticking in a nacelle 100+ metres off the ground!)

    I've seen statements here & elsewhere that it takes a tonne of rare earth elements to make one wind turbine, but I don't know how accurate that information is - my quick searching failed to turn up any such details.
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  41. Doesnt seem an unreasonable number. A number of rare earth elements are routinely used in making magnets. Just remember that "rare earths" mostly aren't that rare.
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  42. Marcus #82

    "Seriously, Ken, I think you need to read a little more widely than the brochures handed out by WMC, BHP & Rio-Tinto. "

    My prior reply was deleted by moderators, but the above ad hominem would seem a clear breach of the comments policy.

    Your points are unsupported by johnd and scaddenup who correctly agree with my comments about the storage of coal and load matching capability of coal fired plant.

    I was a commissioning engineer on a large coal fired C&F plant over 25 years ago, and although engaged in an unrelated industry since then - one does not forget the basics.

    Wind farms take vastly more space for the same output than a coal plant and mine. You tell me how much space you will need for 750 x 3MW wind turbines which would equate to 1 x Kogan Creek.

    And by the way - Kogan Creek would produce 750 x 24 x 365 x 0.9 = 5,913,000 MWhr of energy in a year at 90% availability. Your 3MW wind turbine at 30% availability will produce 3 x 24 x 365 x 0.3 = 7884 MWhr.

    5913000/7884 = 750. 750 Turbines required.
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  43. Ken #89
    My research was done a week or two ago and I'm afraid I don't have any links saved. When I get home I'll try and pull up some of the sites for you. All turbines and electric motors require permanent magnets. Rare earth magnets are really the only ones that can do the job as magnets made by other means are not at all permanent, less efficient and need to be replaced periodically at great cost. The recall the figure of 28,000 tons a year for Neodymium production was based on 2008 figures, but in a graph the production had pretty much smoothed out. China suspending the export of its rare earths is easy to find with a search. Would it be worth me writing all of this up as a blog (with references) and posting a link?
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  44. Vague,

    If you have all the numbers, yes, I'd like to see a nice summary of it. It's an important consideration for ramping up of renewables - the availability of the generation equipment.

    It'd be interesting to see, for instance, how much rare earths are required for a 6-10MW wind turbine, compared to the generator for a 500MW or 750MW thermal power station.

    Ken Lambert - there are wind turbines available up to ~10MW, so that reduces the number required substantially.

    As others have pointed out, the footprint of each turbine is small, though you're right, 250 turbines would spread out over a fairly large area. They don't have to be in a single row, though - in fact, I recall reading something suggesting that 'cascades' of turbines can actually achieve higher efficiency in wind energy conversion.

    If you assume each turbine sits in the centre of a 250m radius circle (probably closer than you'd want to space them in reality), then you get 16 per square kilometre, so ~16km2 for 750MW worth. But, again, very low footprint within that 16km2.
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  45. Ken Lambert, when you start talking about things like fake "medical" conditions associated with Wind Farms, then exactly what am I supposed to assume? Especially when you don't seem nearly as concerned with the very *real* medical conditions associated with the release of mercury, cadmium, radon & particulate emissions by conventional coal-fired power stations.

    @Scaddenp. You were right & I was wrong. I could have sworn I read 60% & 80% efficiencies *somewhere*-but it appears I was mistaken. As it stands, though, regular gas turbines get approximately 45% thermal efficiency, whilst combined cycle turbines get 60% thermal efficiency. However, from what I've read over the last 24 hours, this isn't the final word on gas-turbine efficiency (which is more than can be said for coal, which peaked at 35%). Either way, given that the gas can be obtained from effectively renewable sources-namely decomposing organic material-& has almost *zero* harmful emissions (aside from CO2), then this makes it much better for future energy generation than coal power stations.
    Also, as I understand it, a gas turbine can be built very small, whereas I have always been under the impression that there is a lower limit on how small a coal turbine can be built without *massive* trade-offs in thermal efficiency. So, here again, wouldn't it be better to have dozens of relatively small (50MW-200MW) gas-fired power stations-made up of several 10MW-50MW turbines-spread across an entire State, rather than just a few, very large coal-fired power stations-each of which has to spread its electricity out over *hundreds* of Kilometers?
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  46. "Wind farms take vastly more space for the same output than a coal plant and mine. You tell me how much space you will need for 750 x 3MW wind turbines which would equate to 1 x Kogan Creek"

    Again I ask you-give me the details? How much area does the Kogan Creek Mine site actually take up, & how much will it eventually take up before its life is over? As I said above, the land devoted to a coal mine & its associated power station is *lost* to any other use as long as the power station is in operation-something which can't be said of Wind Turbines. As Bern & I have already pointed out to you, existing technologies already allow for much smaller footprints for Wind Farms than what you claim. If you built a Wind Farm with modern 7MW turbines-with VRB storage-you'd be able to get the output of Kogan Creek with fewer than 200 turbines. You'd also be able to get the output with much, much less energy waste during off-peak periods.
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  47. ....also, Ken, why only focus on Wind? A zero carbon future won't rely on a single source of electricity-it will rely on the integration of several sources of electricity-depending on regional factors. Bio-gas, Wind, Tidal & Solar-not to mention conventional hydro-electric power could easily replace coal for our power needs-especially when you include a decent source of energy storage for Wind, Tidal & Solar. It will also rely on a more distributed system of electricity generation-a move away from the overly centralized approach we have now. Consider it the "networked computing" approach to electricity generation.
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  48. Marcus #95-97 Bern #95

    I am in favour of any energy source which is cost effective and has low or zero emissions.

    Coal and 'carbon pollution' just happens to be the cheapest and most reliable energy source on the Australian scene. Export of coal to less efficient and clean CO2 emitters such as in China, India and other places is a major source of revenue for State and Federal Govts. So while taxing its use here in Oz - those same Govts rely on coal export revenue for balancing budgets and providing foreign exchange so we acvnm but flat screen TV's.

    Those filthy 'carbon polluters' derided by our politicians were (and some still are) none other than State (Taxpayer) built run and owned electricity utilities. The filthy polluters were and are in fact - ourselves.

    What you have to consider is that base load 24/7 from black coal plant generates electricity for 4-5 cents per kWhr, Gas, Nuclear and Geothermal are in the 8-12 cents range. Wind 7-12 cents (depending on site and without storage).

    Solar PV used to be around 50 cents but that could have dropped with falling prices - please update me on this as I have not checked for some time.

    As for medical conditions - coal is not great, nuclear has its risks, wind induced low frequency sound effects are real enough for those affected.
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  49. "wind induced low frequency sound effects are real enough for those affected."

    As I've said, though-why aren't people living even *closer* to the wind-farms suffering from the same effects? It seems odd that no-one who has been paid to site wind turbines on their land has suffered ill effects, whilst people up to 20km away claim their health is being impacted. I'd be inclined to suggest that these people are just miffed at having a wind-farm in their niehgbourhood, or are annoyed at not having received money themselves.
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  50. "What you have to consider is that base load 24/7 from black coal plant generates electricity for 4-5 cents per kWhr, Gas, Nuclear and Geothermal are in the 8-12 cents range. Wind 7-12 cents (depending on site and without storage)."

    Apples & oranges Ken. Black Coal is only so cheap because it has received almost 100 years of 100% tax-payer support & a virtual monopoly in most energy markets-yet even then it took several decades for prices to fall below $1/kw-h. Even today Black Coal receives a number of generous tax-payer subsidies, like cheap water, reduced diesel fuel costs, free infrastructure & subsidized waste disposal & land rehabilitation. Yet not only are its supporters unwilling to consider a removal of these subsidies, but they complain about coal's competitors receiving *any* subsidies at all.
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