Thanks to Luke Walker for alerting me to this:
ABC News: Solar takes off with US power supply deal
Extracts:
Two of America’s biggest power utilities have unveiled plans for a multi-billion-dollar expansion of solar power supply, backing the argument that solar energy can indeed become a viable alternative to coal-fired electricity.
The company at the heart of the development is Ausra. It was started by Australian solar expert David Mills, who left this country for California earlier this year to pursue the further development of his ground-breaking work.
What makes the announcement more significant is that the utilities are confidently predicting that their solar power will soon be providing baseload electricity – that is, day and night – at prices competitive with coal.
Australian technology
The solar technology developed by Dr Mills already exists here in Australia, in the form of small pilot plants attached to the Liddell coal-fired power station in the New South Wales Hunter Valley.
A plant officer explains that the system’s emphasis is on simplicity, with near-flat mirrors on giant hoops tracking the sun.
“Sunlight, on a clear day like this, strikes those mirrors and is gathered up onto the tower, and there’s an absorber underneath that tower,” he said.
Out comes steam, ready to drive a conventional power turbine. This is on a small scale; the new US company started by Dr Mills and Mr Khosla, Ausra, is now planning plants far bigger.
Dr Mills says the first plant size is more than two square kilometres in area and will generate 175 megawatts of power.
“But really we want to aim for gigawatt-style plants, and they’re much bigger than that,” he said.
Assumptions overturned
The coal and nuclear industries have long asserted that baseload power cannot be supplied by renewable energy. That mantra is oft repeated by Australian politicians like federal Environment Minister Malcolm Turnbull.
“You cannot run a modern economy on wind farms and solar powers. It’s a pity that you can’t, but you can’t,” he said.
Prime Minister John Howard says solar is “a nice, easy soft answer”.
“There’s this vague idea in the community that solar doesn’t cost anything and it can solve the problem,” he said.
“It can’t. It can’t replace baseload power generation by power stations.”
But baseload power supply is just what Ausra is now being contracted to supply for the insatiable US market. It says that within two years it will be able to economically store its hot water for more than 16 hours.
Dr Mills says there is a convenient correlation between humans’ power consumption and the sun’s power supply.
“We get up in the morning everyday, we start using energy, we go to sleep at night,” he said.
“And the presence of the sun, that’s natural. And that correlation means that we can get away with a lot less storage than we might have thought.”
Better than coal or nuclear
Dr Diesendorf says the huge US investment into solar will soon make talk of clean coal and nuclear as solutions to climate change redundant.
“Basically, the solar thermal technology will be on the ground, certainly in the United States and many other countries long before so-called clean coal and nuclear power,” he said.
Mr Khosla says solar power is developing rapidly and will be cheaper than either nuclear power or ‘clean’ coal.
Jennifer Marohasy BSc PhD is a critical thinker with expertise in the scientific method.
Sounds great, I hope it works.
Good idea, go for it.
I liked the concept when I first saw the article on Four Corners and had to look up the actual press release from Ausra http://www.ausra.com/news/releases/070927.html .
The plant for one of the power generators is 1000Mw providing 50 million megawatt-hours over 20 years. I may have gotten my maths wrong but the 50 million over 20 years equates to 285 Mw per hour which equates to 28.5% availability (similar to the global average of wind farms}. If you base it on a modern coal fired plant with an availability of 85% {usually higher} the solar plant is really only a 335Mw plant.
This is a good start for the technology but should been presnted in comparision to the coal plant it is suppose to replace. I am focusing on the technology not the carbon reduction due to the claim of replacing baseload capacity.
I know there was a bit of work done in the Hunter open cuts with ‘hot rocks’ and heat exchanges/thermal pumps but like all these things, when push comes to shove…
..but its all good, isnt it Luke.
Like many other intelligent and capable people in Australia in the current narrow minded times. Anyone with a good idea and development potential for solar power such as Dr Mills finds more support elsewhere.
Here so often over the last decade they have received mostly scoffing from the government and its supporters.
Australian solar technology has left with the researchers to Germany, China and now America over recent years, leaving this nation of wingeing yobbos and ignorant fools to watch its rivers run dry and its heart shrivel.
Germany has the biggest domestic solar industry in the OECD.
Bloody stupid Australia, with a lot more sun and space than Germany has gone hardly anywhere.
Germany is also building 15 new coal fired power stations blinky and collectively the OECD looks to contribute more not less to burning of fossil fuels, blinky.
WWF identify Germany and the UK as the location of 10 of the most polluting coal plants in the EU, blinky
50% of german power comes from coal, blinky
Here is the company’s website:
http://www.ausra.com/
Some observations:
1. It certainly is a great achievement that US power utilities are investing so much money in this technology, that says a good deal about its promise I think, and is testament to the work David Mills had obviously put in over decades.
2. Solar thermal technology is an old idea, but, as I understand it, this technology is differentiated by its low cost, land efficient approach to “collecting” the sunlight. California has had the worlds biggest solar thermal installations since the 1980s, hopefully Ausra’s approach will be *better* (read as cheaper).
3. Ah the promise of baseload. Sounds good. But it doesn’t seem to have been tested as yet. As far as I know (could be wrong), the Liddell installation doesn’t use any storage, and it is the storage that is required to make it base load. I don’t think it has been demonstrated.
Storing hot water is simple, so doing that doesn’t need demonstration. But I imagine it is very lossy though, and it does need to be demonstated on economic grounds. And water can only really hold energy up to 100degreesC, before changing phase to steam.
It seems that it is still in the conceptual stages, with hopes to demonstrate it economically within 2 years.
Sounds bold, sounds promising, but stay tuned, it isn’t there yet.
Some quick Mottanese back of the envelope work:
For a gigawatt-scale plant, I’m assuming that they’ll need underground reservoirs in which to store the hot water.
I calculate that, in raising 1 litre of water from 20degC to 90deg C, you can store about 0.3 megajoules of energy.
So for a 1 GigaWatt plant, maybe you want to store 5 hours of rated power output (5 gigawatt-hours.)
5 gigawatt-hours = 18 million Megajoules (1 kilwatt-hour = 3.6 megajoules)
18,000,000 / 0.3 = 60 million
So you’d need maybe 60 mega litres of water to store that energy. Thats a space the size of a warehouse measuring 100m x 60m x 10m high.
Or maybe I’m wrong in assumnig they are storing hot water, maybe they are storing pressurised steam or something? Can store a lot of energy in that phase change from liquid to vapour, if you can economically store the steam…..
Peter – “This is a good start for the technology but should been presnted in comparision to the coal plant it is suppose to replace. I am focusing on the technology not the carbon reduction due to the claim of replacing baseload capacity.”
Part of Ausra’s technology is heat storage. Eventually heat will be able to be stored for up to 2 weeks for times when the sun is not shining. Additionally solar power quite neatly follows patterns of energy use. Peak demand very often correlates with peak solar output.
What this means it that at night instead of having hundreds of megawatts of inflexible baseload sitting around doing nothing at off-peak times the solar plants will naturally follow the peaks and troughs of demand.
In an integrated smart grid of renewables comprising geographically spaced wind, solar thermal, solar PV, geothermal, wave and tidal power there will be sufficient storage in both heat at solar thermal plants and electricity in V2G cars to ensure 24X7 power to supply demand. There will also always be, as there is now, an operational reserve of gas fired turbines that can respond quickly and automatically to changes in demand. These gas turbines can be powered from natural gas while it lasts, gasified coal while it lasts, or stored hydrogen from waste biomass.
The last thing that the future grid needs is inflexible 19th century baseload power stations. The quicker that these can be phased out the better in favour of much more flexible intermediate or peaking power generators the better.
Good point Ender.
People think baseload is the be all and end all of power. But baseload doesn’t respond to peaks – a power grid cannot rely on 100% coal any more than it can rely on 100% wind, because coal isn’t responsive enough. That’s why peak generators such as hydro and gas are needed, and they charge a premium for their responsiveness.
In any functioning grid, their will be a mix.
Baseload to provide much of the kWh, peak load to provide the kW when and as its needed and match supply with demand, and “green load”, to reduce the greenhouse intensity of the grid as a whole.
Steve – “Or maybe I’m wrong in assumnig they are storing hot water, maybe they are storing pressurised steam or something? Can store a lot of energy in that phase change from liquid to vapour, if you can economically store the steam…..”
It is more likely to be molten salt:
http://www.sandia.gov/Renewable_Energy/solarthermal/NSTTF/salt.htm
http://www.volker-quaschning.de/articles/fundamentals2/index_e.html
Steve – “Baseload to provide much of the kWh, peak load to provide the kW when and as its needed and match supply with demand, and “green load”, to reduce the greenhouse intensity of the grid as a whole.”
The key is to gasify the coal. Gasifying it makes it much easier to capture the CO2 and the power station that uses gasified coal is a intermediate or peaking plant (gas turbine). The same plant can be fuel flexible and use gasified biomass just as easy as gasified coal. The main point is that only a small part of the modern grid should be inflexible baseload. Intermediate and peaking fossil fuel power plants are much more suited to interfacing with renewables as they have automatic controls and can vary their output economically within seconds to minutes.
We do not have to eliminate ALL fossil fuel use only get its use under 30% where CO2 emissions can be stabilised. Nuclear power has no place in the future as it is baseload only quite apart from it’s massive waste disposal and proliferation issues. Really NP is good old Victorian power with a fancy new way of heating water. If anything it is less flexible than coal and is only partially economic run flat out all the time – there is no in between. And before anyone asks France uses pumped hydro from Sweden to supply its peaking demands.
The Howard government has run dead on this issue for ten years, and only given it token support. Looks like research can give us ways to reduce our use of fossil fuels. They have had billions of dollars in surplus from the resources boom and an unprecedented are of global economic growth, and blown it on tax cuts that are just being used for big screen TVs and property speculation. In the years to come, Howard will be seen as one of the most ignorant and incompetent Prime Ministers in our history.
The idea looks fine in concept but what about the detail.
How much water is used to keep all those mirrors clean and at maximum efficiency? There’s a lot of mirrors so at 250ml per mirror per day that’s a lot of water.
How does the efficiency of the system vary at latitudes outside let’s say 30 degrees?
Another way of storing electricity is by electric storage water heaters in peoples homes. When there is an excess of power the heaters are turned on by the power utility.
Heating water electrically is inefficient but maybe not as inefficient as storing the hot water before generation into electricity.
Ender,
The whole point was that this station{s)are said to be 1000 Mw but that is not a continuous rating,its more like 335Mw plant. The storage capcity of the heat is only 20 hours not 2 weeks at this stage but the greater the storage time the more complex the system which goes against what Ausra is trying to achieve.
Baseload is the minimum continuous power demand that is required by the network which is the problem wind,solar etc at this time, Peakloading is handle by quick response system. Systems have to be developed to cover all the critera and renewables at this stage are not ready.
Peter – “The whole point was that this station{s)are said to be 1000 Mw but that is not a continuous rating,its more like 335Mw plant. The storage capcity of the heat is only 20 hours not 2 weeks at this stage but the greater the storage time the more complex the system which goes against what Ausra is trying to achieve.”
The continuous rating is of little importance if the power station is not required continuously. Large coal plants that cannot be shut down are run continuously anyway consuming fuel but not producing electricity. Most power is just not needed at night. The heat would be exhausted in 20 hours however it can be stored for 2 weeks or more The length of time that the solar plant can run without sun is only dependant on the size of the molten salt tanks and can be added to if necessary without adding to complexity.
“Baseload is the minimum continuous power demand that is required by the network which is the problem wind,solar etc at this time”
You are fundamentally misunderstanding the term baseload. It is a common misconception and is perpetuated by fossil fuel interests.
Baseload is a type of power station. It is the type that have the operating characteristics that are is very slow to start up and shut down and change output. Baseload plants can take days to start and stop therefore the only way these plants are economic is to run them flat out all the time. Nuclear and Thermal Coal are of the type baseload.
Any power plant from solar PV on a roof can contribute to what you call ‘baseload’. Peaking plants are usually gas turbines or diesels. At any one time the current power demand can be met by any combination of available power generators and renewables are ready now to contribute. Right now the NEMMCO is legislated to have 800MW of operational reserve to instantly take over the load of a failed coal generator. Any single wind farm is far less than this and most can be coped with with normal reserves. Solar plants are not nearly as intermittant and wind plant are already adding increasingly cheap storage to make them more despatchable.
Try reading a few documents at the NEMMCO. You will have a far greater understanding of how power generation is manage and avoid mistakes like misunderstanding baseload.
http://www.nemmco.com.au/nemgeneral/NEM_general.htm#Publications
Ender,
The article that Luke has linked to indicates that they are aiming for baseload meaning that they will be able to produce power day and night.
Remember to produce that 1000Mw per hour during the night they must store the equivalent amount during the productive daylight period. They will have to oversize the plant to a large degree. Unfortunately at this stage I cannot find their expected power production curve so I don’t know what that will be but the indication is that if the said plant produces 50 million megawatt hours is converted to a baseload projection which they are aiming for it would equate to 335 Mw plant coal fired power station. My gripe is the description of the capcity such as in the article and my pet dislike in other similar types of articles 40,000 homes (it is meaningless).
You should possibly read some more of the NEMMCO documentation on alternative energy sources such as wind power and see how they define them. There will always be baseload need i.e minimum power required by the community over a 24 hour period 365 days a year allowing for seasonal changes. It is not as dynamic as peak power and as the peaking plant power is expensive the lower cost continuous power (compared to other forms of power)is the baseload or intermediate load providers.
Peter – “They will have to oversize the plant to a large degree. ”
As what happens now. Coal Plants do not produce power 24 X 7 for 365 days of the year. There are extended maintenance periods and failures. An old plant can have a capacity factor as low as 75% so the power generation system is ‘ovesized’ at present.
“There will always be baseload need i.e minimum power required by the community over a 24 hour period 365 days a year allowing for seasonal changes”
Yes you are right however there is no difference from supplying that demand from renewables. With widely spaced renewable power stations using different forms of renewable power there will always be some power being generated somewhere. And there will always be the requirement for generators using stored fuel somewhere. There is absolutely no reason why gasified coal cannot contribute up to 30% of the energy mix. Even more so if CO2 capture and storage can ever be made to work.
“My gripe is the description of the capcity such as in the article and my pet dislike in other similar types of articles 40,000 homes (it is meaningless).”
You need to come to terms with the concept that is used with power stations of capacity factor. I do not like the description of 40 000 homes etc either however this is the only way most people can relate to electricity. Most people do not know what a kWhr is. I constantly get asked to put the term watt into something that others can understand.
The articles that give you an analogy to homes are not meaningless. They look at annual energy (kilowatt-hours), not rated power output (kilowatts).
E.g. the average home in Sydney uses about 8,000 kilowatt-hours , or 8 megawatt-hours, per year.
A single 1 megawatt wind turbine at 35% capacity factor produces 1 x 0.35 x 8760 hours in the year
= 3,066 megawatt-hours per year.
3,066 / 8 = 383
So the description is that a 1 megawatt wind turbine produces enough electricity over the year to meet the yearly electricity consumption of 383 homes.
You shouldn’t be upset Peter when people talk about rated power output instead of average power or energy etc. Energy is complex, and you just have to deal with it, and make sense of it, rather than jumping to conclusions, or jumping to a conspiracy. I’m an engineer and I think it the units that are used for power vs those for energy, and the difference between them are confusing, not to mention the difference between instantaneous power, average power and rated power. Its been complicated like this for decades, its not a new thing that renewables companies are doing to appear better than they are.
For example, the total installed, rated power output of all generators in NSW combined is something like 12 gigawatts. And yet the AVERAGE power consumption (yearly energy consumption divided by time) is closer to 8 gigawatts.
Being told that the NSW has a rated power output of about 12GW only tells you what we can cope with on the hottest (or coldest) of days when the grid is at its breaking point. But there is a enough reserve capacity that we rarely reach that point, in fact we only come close a couple of days a year. That should also suggest to you what a mistake it is when you assume that a generator has to operate 24/7, 365 days a year to be classified as ‘baseload’. Most generators in Australia, whether coal or otherwise, don’t fit that description.
Steve,
Baseload and baseload power plant are to different things. Load is a demand on the system, generation is the response to the demand.
The point about the NSW system being capable of 12 gigawatts but usually only 8 gigawatts reminds me of Cain/Kirner/Kennet sell off of the SEC(V). They stated they had plenty of power available (I think they were claiming 10 gigawatts) but the reality was that there was a lack of reliable low cost power supply.
As for appearance it is misleading just as there has been claims that windpower had nearly 100% availability but the definition of availability had been changed though the Actual Capacity Factor was a lot lower than the thermal plant. This seems to apply to the Ausra plant. In this world of Nemmco there would be a willingness to chase the dollar and not look at system needs. If they wish to make this plant a baseload plant capable of producing a sizable output overnight they will have to restrict the output of the turb/generator hence my comment that the continuous output was more like 335 Mw.
All that being said I liked the Ausra concept when I first saw it because of its general robustness and what seems like current cheap (relatively) componets unlike the say the Solar Farm that is set to be built near Mildura. By the way does anyone what is happening with the Solar Tower that was suppose to be built out there.
Ender I usually equate it to the number of 2 Kw bar heaters it can supply and for how long but it is still big numbers.
Steve,
Are you sure you don’t work for a windmill company? You said you work for gummint. Department of Windmills? Minister Don Quixote? CEO Sancho Panza? Windmills are a blot on the landscape. Now algae that produce hydrogen (Quantum last night) – I like it.
Peter – “Baseload and baseload power plant are to different things. Load is a demand on the system, generation is the response to the demand.”
There is no such thing as baseload – it is an imaginary term that is misunderstood. True load is the amount of demand on a system and generation is the response however demand varies over the day and over the seasons and can be satisfied by any combination of whatever power generation capacity is available.
Demand never drops to zero and up until now the most efficient way of satisfying the minimum demand was with a power station that is more efficient running flat out than changing to meet demand. Up until recently only large power stations were economic however that is now not true. It is just as efficient to generate a kWhr from a 1kWhr solar panel or a 100kW microturbine as it is from a 1GW Coal Plant. Up until now this has not been the case and large power stations were the only way electricity could be generated efficiently and the old technology did not scale down at all.
Baseload power stations got their name from the fact that they were the best things for the largely unvarying base of the daily/yearly demand curve however it is not true today. Anything can deliver the base as long as it is despatchable. Coal operators desperately trying to remain valid in a changing world where they might have to actually pay for their greenhouse emissions they have invented the term baseload and invented the idea that coal plants are the only thing that can deliver it.
“If they wish to make this plant a baseload plant capable of producing a sizable output overnight they will have to restrict the output of the turb/generator hence my comment that the continuous output was more like 335 Mw.”
Again you are fundamentally misunderstanding how power stations operate. Are you suggesting a thermal coal plant of 1GW be called and 850MW one because it has an 85% capacity factor? Or a nuclear power station that is down for 2 years because of defects be downrated from 1GW to 0GW. The rated output of a power plant is independant of the capacity factor.
“If they wish to make this plant a baseload plant”
It already is a baseload plant as it is a thermal steam turbine that I am pretty sure will not be able to be varied quickly so it would be classified as baseload at worst or intermediate at best.
Davey – “Are you sure you don’t work for a windmill company? You said you work for gummint. ”
No sorry struck out on both there.
Ender,
If a thermal (coal or gas) power station was said to be a 500Mw unit it will if it is mechanically, electrically sound and inputs i.e. fuel, water etc are available it will produce 500Mw as a maxium continuous rating MCR (there are always slight caveats to this but they are usually close). This means that its availability capacity factor (ACF) is 100% if it can maintain the 500Mw 24/7. As factors such as fuel, temperatures, mechanical and electrical failures, outages for overhaul and cleans (note not demand or load) then affect the ACF reducing the factor to whatever but this thermal station is still a 500Mw unit.
On the other hand the Ausra plant is 1000Mw but I presume that this maxium would be for a certain period of the day but the “fuel” the sun degrades and then vanishes as the Earth rotates that means its ACF is reducing from 100% to if their figures are correct to 28.5% over the day/week/year. Not good in terms of control of the network i.e voltage and frequency. So to supply this generation as “baseload” (their claim i.e “predicting that their solar power will soon be providing baseload electricity – that is, day and night – at prices competitive with coal.”) like a “baseload” thermal power station which is available 85% (the ACF) of the time the solar heating system has to be over three times the size to feed the “heat sink” or the 1000Mw must be dropped to approx 335 Mw either way the solar farm has to be a multiple of over 3 to achieve this based on the figures in this article.
Baseload plant is the lower cost, reliable power (closer to 100% ACF than discussed)suppliers compared to say the peak generation which will be high cost and/or unreliable i.e. its “fuel” water, sun etc but usually quick response.
Ender I will guarranttee that if you wished to rely on a solar cell at home (no mains or fossil fuel backup) that you would oversize the capicty install and add batteries to enable you to operate day and night. Your base load would be the fridge, the standby power on your aplliances, the light that one of the children has left on, the electric alarm clock anything that consumes electricty day and night even thogh you aren’t at home. In a large network they also include buisinesses (the nightclub that runs all night), factories that run 24 hours a day and still be able for you to switch on the light at 2 in the morning to find out what the dog is barking at. This is some of the things that Nemmco has to allow for and they know to a fair degree what the minium power requirements are at certain times of the year hence the warnings about not having enough capacity in the system that they sometimes give and I am sure that you would not want to pay the maxium 10,000 dollars a Megawatt that could occur if the peaking plant has to be continually used.
Baseload will be here to stay but it is the definition/excepted wisdom of baseload plant that may change.
Peter – “f a thermal (coal or gas) power station was said to be a 500Mw unit it will if it is mechanically, electrically sound and inputs i.e. fuel, water etc are available it will produce 500Mw as a maxium continuous rating MCR”
Look you are absolutely and completely wrong here.
http://en.wikipedia.org/wiki/Capacity_factor
This is a good definition of capacity factor. There is no powerplant in the world that has a 100% capacity factor. For this it would have to run 24 X 7 X 365 with no maintenance and no failures. This is clearly impossible. There is also another term called availability. You cannot get power out of a coal plant that is down for maintenance. A wind farm with its drastically lower maintenance requirement has, given a good wind, a higher availability. A shut down coal plant even though there is coal in the bunker cannot deliver any power.
“solar heating system has to be over three times the size to feed the “heat sink” or the 1000Mw must be dropped to approx 335 Mw either way the solar farm has to be a multiple of over 3 to achieve this based on the figures in this article.”
Only if the solar plant was the sole supplier of power as would be a standalone rooftop solar plant. In a future power supply system the solar plant would be a part of a network similar to today. You could not have a system that comprised 100% thermal coal or 100% nuclear power as these systems cannot do peaking loads. Our present coal plants are backed up with peaking plants. Also the system is already oversized to cope with the lower availability of thermal coal. Any solar thermal plant would also have wind, geothermal, IGCC coal plants, natural gas, tidal, wave etc power plants that will satisfy the current demand whatever the time of day or the season.
The thing that you are not allowing for is that power is more valuable depending on the time that it is available. For instance a roof top solar array cannot be relied on 24 X 7 without backup batteries. However connect it to the grid and it’s value magnifies. One of the greatest recent demands is home airconditioning and it it threatening to overwhelm the grid. Grid-tie solar systems deliver power at precisely the times of greatest demand ie:when it is hot and sunny. Therefore the value of the power is much greater because it is delivered when it is needed. If the coal plants that delivered to grid power was more reactive it could be easily scaled up and down in response, saving greenhouse emissions. As it is now those coal plants are still running flat out however producing nothing and never able to change fast enough to make large savings. This is why renewables with coal do not deliver the emission savings that are predicted.
Ender.
Note it is the articles point that it could run day and night.
Your examples contain 2 fosill fuel plants and others that have either have to have storage facilities of some sort (which is Ausra’s claim) or you only take them when they can supply (not pricing but when the sun is up or the wind blows). Geothermal is probably the only one that will work.
So Ender you are advocating fossil fuels. Why would you? I know. You want that consistent power supply for the load requirements part of which would be called baseload with wind only being approx 30% available (global) solar about the same. You must be in the pay of big coal.
Seriously though I know there are mixes hence the baseload, intermediate and peaking. I am only pointing out that to get to a baseload plant solar (photovoltaic or steam generator) would require a large storage system which would have to be filled if the supplier wants 24 hour production (Ausra will if they get it as cheap as coal plant i.e. profit hopefully 24 hours a day not just for 8 hours).
Ender,
The definition you linked to for the Capity factor is Availabilty Capcity Factor (ACF). The ACF changes on power plant as it requires cleaning, runs out of fuel, mechanical and electrical problems etc. So no Ender I am not “absolutely and completely wrong here” or do you think that plant should not be able to run at its rated capcity at all or as I noted the Maxium Capcity Rating (MCR) which the ACF will be based on.
Peter – “So Ender you are advocating fossil fuels. Why would you? I know. You want that consistent power supply for the load requirements part of which would be called baseload with wind only being approx 30% available (global) solar about the same.”
No I am advocating a mix of power with fossil fuels reduced to less than 30% and absolutely no nuclear. I am not a renewable power zealot and I admit we will need a mix of power sources to power the future however the absolutely last thing we need is more baseload. We need more intermediate such as co-generation gas turbines burning either gasified coal, gasified waste biomass or natural gas. We need vastly more solar thermal, solar PV, wind, wave, tidal and geothermal. Coupled with large scale storage and new HVDC transmission lines with superconductor storage the requirement for fossil fuels will diminish as V2G cars and other storage take over the regulation and operational reserve.
One of the tasks that wind flow battery storage can do really profitably is grid regulation. The power converters that change the DC battery voltage to AC can also change phase, voltage and frequency instantly under automatic control to supply the extremely valuable ancillary services to the grid when wind farms with storage become more common. One is already installed at King Island.
http://www.metaefficient.com/archives/renewable-power/australian-island-using-flow-batteries-to-store-wind-power.html
Ender,
I was sarcastic but the link that you provided was interesting but again they are aiming to be as baseload type plant as possible considering that would be a small network. They have increased their contribution to the network from 12% to 40% by diverting unused power to this flow battery system. King Island is a small network but my stance is still the same. The wind generators are capable of X amount of generation at optimal conditions, they divert power to the battery system to achieve a larger portion of the load or demand without increasing the to amount of windmills. The network is small and has larger variabilities than say the East cost network and as such a very small baseload if any and are able to charge their flow batteries when the wind blows and demand is lower.
So what after all this is your problem with my statement that the Ausra 1000Mw plant with the restrictions given in the article and had to operate day and night at a consistent output (using some form of storage)which is their aim that it would be approximately equivalent to 335Mw coal fired low cost plant baseload plant with an ACF of 85%. Remember most people if they were asked to tell you the output of a Hunter Valley Power Station they are more than likely to quote the maxium continuous rating. I was setting some common prespective getting away from the number of homes supplied or 50 million megawatt hours over 20 years which mean very little to the person who sees these large power stations but doesn’t realise that the Ausra plant power output quoted is really only its “peak” output (I don’t like the term, it would be getting confusing with peak load)and hence a smaller plant than the 660 Mw unit they see in the their “backyard” in total capacity.
It was not about network stabilistion, power mixes etc just a reasonable comparision to the average person.
Peter – “So what after all this is your problem with my statement that the Ausra 1000Mw plant with the restrictions given in the article and had to operate day and night at a consistent output (using some form of storage)which is their aim that it would be approximately equivalent to 335Mw coal fired low cost plant baseload plant with an ACF of 85%”
None at all except that at least now you are understanding the concepts of capacity factor and peak power etc. However you still comparing apples with oranges. Just because the solar plant has a lower capacity factor does not mean that it is inferior. The only reason that a coal plant can be low cost and operate 24X7 is by externalising all environmental costs and using highly concentrated stored sunlight at fuel.
At last coal operators are going to have to start paying for external cost that up until now they have been able to avoid. In this regime the solar plant’s zero CO2 and aerosol emissions make up for it’s lower capacity factor. As long as sufficient storage is provided in both thermal and electrical means then electricity will be available when it is needed. Additionally if we drive the storage around as well, as we will when vehicle to grid cars come on the market, we can solve the other major problem we are facing, that of Peak Oil.
Ender,
My understanding is the same as at the start of this discussion and it is you who seems to jump the gun. The meaning of availability capacity factor, continuous rating, baseload requirements and what is actually stated in the article which I have discussed with you haven’t changed.
The Ausra plant seems like a fairly versatile system which may supply a fairly consistent power source if they are solving any storage technology (likely). The real benefit is the is that it doesn’t seem to use very energy intensive processes to make the components unlike some photo voltaic systems
Don’t be to sure about the environmental costs I am sure governments will find other ways of taxing even “environment friendly” plant due to their influence on the environment (to top up their budgets. Now I am cynical.)
Be aware of the externalising of environment costs due to the fact that basically very little business is truly willing to “internalise” their environmental costs.
Oh by the way at least in the Western world coal fired plant do reduce some of their external environmental conditions, believe me if you they didn’t the particle pollution, sulphur and nitrous emission would be a lot worse. I know you will say that society has made them but then society is what sets the benchmark, whether in industry, law, morals, art the list goes on.
Peak oil the only thing I know is that there have been many claims of when peak oil would occur.
The last thing is that the electric car will become a common technology when the battery/storage system and associated support(charging, changeover and disposal)are dealt with while maintaining low cost (primarily purchase price to that of its petrol driven cousin).
Dear Sir/ Ma
Good Day,
We would like to inquire if you have in stock or can help us get 80 watt or 123watt solar panel and Xantrex Charge Controller 30 to 60 ams . Please advise your unit pricing as we would be buying upto 10 or 12 units of this material from you for our upcoming project.
And also let us know the credit card type you welcome for payment.
Thanks for your anticiapted business relationship and cooperation.
Thanks
Steven Douglas
10420 Kinsman Rd
Newbury,OH 44065