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You didn't mention renewables, for basillio.
I won't enter any personal debates, but here's how power generation is shifted from one source to another without actually building any new power stations.
This is for a hypothetical grid, but it's broadly similar to the situation in Victoria. Suppose that you have (for simplicity I'm ignoring maintenance outages etc here and keeping it in layman's terms).
Peak demand of 10,000 MW
Maximum load on a mild day of 6,000 MW
Average demand of 5,500 MW
Normal minimum (excluding blackouts due to storms etc) demand of 4,000 MW
Coal-fired generation of 6,000 MW
Hydro generation of 2,000 MW
Gas-fired generation 2,500 MW
On a hot day with peak demand, you have to run basically everything flat out or very close to it. You therefore have no choice as to where the power comes from - all available generation needs to be running and there's nothing to spare.
But at other times you have a lot of choice. Technical factors limit the ability to switch coal plants on and off, but they can certainly be ramped up and down from full load down to (depending on the plant design) 30 - 60% of capacity.
So on a mild day with 4,000 MW overnight and 6,000 MW during the day there are a lot of options:
You could meet the entire load from coal, apart from some hydro or gas online as spinning reserve (in case a unit breaks down suddenly).
Or at the other extreme you could have 2,500 MW of coal-fired plant online, only running at 2,000 MW, and fully use the available gas and hydro.
For hydro it is usually a case of having a limited water supply and choosing the best time to use it which is itself influenced by recent inflows. If it's dry then run it only to meet the peaks (saving water). If there's a flood then run it flat out 24/7. If it's moderately wet then just run it during business hours. Etc. This is how hydro is normally used in a predominantly thermal (fossil fuel or nuclear) system.
But for coal versus gas it is simply a question of economics. If coal is cheaper then you prioritise the use of coal and minimise the use of gas. Reverse that if gas is cheaper.
A complicating factor is that costs are not fixed per unit of output. Eg it costs money to have a coal plant online in the first place, but getting extra output from it is cheap once it's online (you already have staff there, everything is already running etc). So depending on the economics this will change the desirability of using gas versus coal and create a "lumpy" effect. Eg with a carbon tax at a high enough rate it makes sense to keep coal units offline where possible, but once it's running it may still be cheaper to run it flat out and use less gas.
But the overall principle is straightforward. Make coal cost more than gas, and some production will tend to shift from coal to gas, thus cutting the use of coal and increasing the use of gas. That said, it hasn't happened to any major extent with the actual carbon tax we have. There has been a bit of an increase in gas-fired baseload and shoulder period (ie business hours) running, but if you look at it right now then the brown coal plants in Victoria are, with one exception, running at or close to maximum capacity whilst the gas-fired plants are offline doing nothing. So you'd need a considerably higher rate of tax in order to bring about a large scale shift from coal to gas based on the existing power stations.
What about new power station construction? A carbon tax will certainly favour gas over coal. But once built, it still comes down to the day to day running costs. Eg Mortlake power station (Vic) is a brand new gas-fired plant of medium efficiency. It is sitting idle right now whilst the coal-fired plants are running. Meanwhile there are gas-fired units online in SA operating well below capacity with about 22% of the SA load being supplied from Victoria. Enough said.
For a hydro generator it is basically about having a limited supply of fuel (water) and trying to get the best price for it, subject to system constraints.
It's public knowledge that Hydro Tas is pushing the system as hard as possible whilst the carbon tax is in place in order to maximise revenue. That is certainly not something that has ever been denied, indeed it was publicly announced in July 2012 when the tax commenced that this was the strategy being pursued. Needless to say, production will be throttled back as the carbon tax ends.
http://m.smh.com.au/technology/sci-tech/csiro-support-staff-face-huge-job-cuts-20140314-34so6.html
CSIRO support staff face huge job cuts
..widespread expectation that much of the agency will be privatised with the loss of up to 3000 public service jobs..
..Heads are also expected to roll among the CSIRO's executive ranks with the 22 bosses of divisions and flagships, who all have support staff, vying for just nine jobs heading up the restructured research flagships.
You didn't mention renewables
Climate Change: Evidence and Causes
Climate Change Evidence and Causes Booklet
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https://nas-sites.org/americasclima...ussion-on-climate-change-evidence-and-causes/
About the Document
The leadership of the U.S. National Academy of Sciences and the U.K.’s Royal Society convened a UK-US team of leading climate scientists to produce this brief, readable reference document for decision makers, policy makers, educators, and other individuals seeking authoritative information on the some of the questions that continue to be asked.
The publication makes clear what is well-established and where understanding is still developing. It echoes and builds upon the long history of climate-related work from both national academies, as well as on the newest climate-change assessment from the United Nations’ Intergovernmental Panel on Climate Change. It touches on current areas of active debate and ongoing research, such as the link between ocean heat content and the rate of warming.
Thanks for the link Bas and to you Smurf... 'your worth more money'
I bet Basillio, didn't know the ramifications of the current water usage, also the problem with having to supply the baseload to cover the unreliability of boutique renewables.I did not want to say this but maybe they should be paid in "Carbon Credits" ?
I bet Basillio, didn't know the ramifications of the current water usage, also the problem with having to supply the baseload to cover the unreliability of boutique renewables.
QUOTE]
Water consumption from coal plants
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Power generation has been estimated to be second only to agriculture in being the largest domestic user of water.[1] To produce and burn the 1 billion tons of coal America uses each year, the mining and utility industries withdraw 55 trillion to 75 trillion gallons of water annually, according to the US Geological Survey.[2]
Thanks for the analysis and summary Smurf. Really clear.
So it seems that for the short term the direct effect of the carbon tax has been to switch power generators. from coal fired power stations to hydro as far as possible. Current wind and Solar generators just keep on going regardless of the carbon price. (I wonder however if the power companies can refuse to take supply if they can get it more cheaply from coal? I think however that the current legislation that demands a certain percentage of renewable energy takes care of that issue )
So when the carbon tax is taken off coal fired stations come back into full production including those that have been mothballed because of the tax. Up goes our CO2 emissions
And then the government attempts to use direct action to reduce CO2 emissions......
Is that an accurate interpretation ?
Cheers
QUEENSLAND'S largest power generator will today declare that Australia is one of the world's most expensive countries for energy and warn that the electricity market is being distorted by the carbon tax, mandatory renewables target and solar-rooftop subsidies.
After Stanwell took the extraordinary step yesterday of announcing it would mothball its biggest gas-fired power station and resurrect a coal facility built in the 1980s - sparking predictions that gas-fired power plants would be withdrawn in other states - it will today call for a scaling back of the renewable energy target.
Before the introduction of the carbon tax, the RET scheme and solar feed-in tariffs, the abundance of coal had made Australia a source of low-cost electricity, the company will say.
"These policies appear to have been implemented for ideological reasons with little analysis of the impact on electricity prices and economic growth," Stanwell chief executive officer Richard Van Breda will say.
As described above, the continuing reduction in summer daytime demand is manifestly cutting the lunch of the big generators, eating into their most profitable trading periods. Unsurprisingly, we are now seeing significant push-back by the energy utilities in an attempt to restrict further take up of the new distributed technologies, and the incentives that have motivated their take up.
While that’s hardly a surprising reaction from an incumbent, what is surprising is how long its taken for the industry push-back. Now some five years into the decline and the question is, is it too late?
In its crudest form, the electricity business model has been focussed above all else on selling more electrons. But after yet another summer on the NEM, it is clear that customers are not buying it.
And looking at the trends, you’d have to be crazy to think the decline will stop. Not only is demand for “poles & wires” electiricty declining because of the new technological drivers, but big energy users are also exiting the market, making for a perfect storm. The recent announcement that the Point Henry aluminium smelter will close, effectively commits a further reduction in 350 megawatts - representing about 1.5% of NEM consumption (~7% of Victoria).
The total emissions, excluding increases in emissions from land-clearing, came in at 542.1 million tonnes of carbon dioxide equivalent for the year to September, or 0.3 per cent lower than a year earlier. When changes in land use are added, overall emissions for the 12 months came to 567.5 million tonnes, or 1.2 per cent higher.
Pollution from transportation, not covered by the carbon tax, has been rising steadily, while emissions from coalmine expansion and new gas plants have been soaring. The latter two sources are only partially covered by the carbon tax, now at $24.15 per tonne, with offsets or free permits reducing the cost to polluters.
Dr Pachauri's views contrast with arguments in Australia that views outside the orthodox position of approved climate scientists should be left unreported.
Unlike in Britain, there has been little publicity in Australia given to recent acknowledgment by peak climate-science bodies in Britain and the US of what has been a 17-year pause in global warming. Britain's Met Office has revised down its forecast for a global temperature rise, predicting no further increase to 2017, which would extend the pause to 21 years.
THE UN's climate change chief, Rajendra Pachauri, has acknowledged a 17-year pause in global temperature rises, confirmed recently by Britain's Met Office, but said it would need to last "30 to 40 years at least" to break the long-term global warming trend.
When you almost solely use material from The Australian as your source TS you are in trouble if you are trying to establish facts. On CC The Australian is a systematic liar (with a very few honorable exceptions)
The big talking point from CC deniers in the past few years has been the alleged failure of temperatures to actually rise. Or at least that is the story The Australian and co want to push.
One of the biggest users of water at the moment are the coal fired power stations. Use squillions of litres for the cooling towers and other systems. The URL I listed below is well worth reading on this point
In the longer term the development of solar thermal power stations could replace coal with no need for back up. The fast development of industrial size battery systems is also an option to temporarily store power from wind /solar energy.
http://www.sourcewatch.org/index.php?title=Water_consumption_from_coal_plants
Finally, Some Real Climate Science
The American Physical Society has been amongst the loudest alarmist organisations whipping up hysteria about CO2, but a review of its position that has placed three sceptics on the six-member investigatory panel strongly suggests the tide has turned.......
An Alarming Wake-Up Call From A Brand New Report On Climate Change
Dina Spector Today at 6:57 AM
January 2014 Land and Ocean Temperature PercentilesAccording to NOAA scientists, the globally averaged temperature over land and ocean surfaces for January 2014 was the highest since 2007 and the fourth highest for January since reliable record keeping began in 1880.
The evidence linking human activities to climate change is as strong as the data supporting the idea that smoking causes lung cancer, a new report from the American Association for the Advancement of Science (AAAS) warned on Tuesday.
“Many people do not yet understand that there is a small, but real chance of abrupt, unpredictable and potentially irreversible changes with highly damaging impacts on people in the United States and around the world,” according to the “What We Know” report.
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