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Post by trag on Feb 9, 2013 3:31:46 GMT 9.5
www.theregister.co.uk/2013/02/07/wind_power_cheaper_than_new_coal/This article, followed back to its source, has Bloomberg Financial claiming that unreliables are cheaper than fossil fuel electricity generation and that all new generation in Australia should be from unreliables. While I certainly don't object to eschewing fossil fuel generation, the idea that wind or solar is affordable, much less practicable has been disproven again and again in the real world. Any ideas on Bloomberg's motivation?
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Post by David B. Benson on Feb 9, 2013 16:28:01 GMT 9.5
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Post by sod on Feb 11, 2013 5:33:06 GMT 9.5
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Post by David B. Benson on Feb 11, 2013 11:57:10 GMT 9.5
Not only sunning but maybe even stunning as well.
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Post by anonposter on Feb 11, 2013 15:08:12 GMT 9.5
Reducing peak demand when the days are sunny, not doing anything of note on days that aren't sunny.
That isn't really very useful as you need the capacity available.
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Post by David B. Benson on Feb 11, 2013 15:24:55 GMT 9.5
Anon --- Having the corresponding graph for the winter quarter in South Australia would certainly help.
Nonetheless, the article did say that one coal burner has been permanently turned off.
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Post by sod on Feb 11, 2013 18:36:00 GMT 9.5
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Post by sod on Feb 11, 2013 20:59:15 GMT 9.5
by the way, what is the "unreliable" part of a power source, which is delivering power when demand is at its peak?
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Post by anonposter on Feb 12, 2013 0:18:51 GMT 9.5
What happens when a cloud rolls in?
I'll tell you what happens, you lose most of the solar power and if you don't have a gas turbine standing by you get a blackout.
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Post by sod on Feb 12, 2013 5:37:57 GMT 9.5
What happens when a cloud rolls in? I'll tell you what happens, you lose most of the solar power and if you don't have a gas turbine standing by you get a blackout. when a cloud rolls in, absolutely nothing will happen. we are talking about spread out roof top solar. it will not notice a single cloud. But if you are talking about a cloudy day, we get a different situation. But again, there will be neither blackouts nor will we need gas turbines on stand by. Please look at the pdf, which i linked above. temperature and power demand are closely correlated. hot days - big demand - much solar power cool days - low demand - little solar power
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Post by David B. Benson on Feb 12, 2013 9:48:59 GMT 9.5
In addition, the wind turbines produce more in the winter than in the summer.
However, the general point of requiring dispatchable balancing generators for wind and reserves for solar remains. The cost of both must be considered.
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Post by sod on Feb 12, 2013 18:30:58 GMT 9.5
However, the general point of requiring dispatchable balancing generators for wind and reserves for solar remains. The cost of both must be considered. you are right, of course. But we also have to factor in the benefit of solar, for example on peak demand. (a price reduction that often isn t factored into consumer bills) and back up will often come from old plants (so we do not need to factor in construction costs) or gas plants, which were build under optimistic assumptions. (gas plants build today as base power plants will do nothing but reserve duty for the majority of their life time) as the article in original post mentions, the future is indeed looking grim for coal. in South Australia, wind is producing more power than coal. theconversation.edu.au/wind-power-why-is-south-australia-so-successful-9706and over 7% is up all the time. (and does not need more back up than other plants) wind plants might even have a higher capacity factor than old coal plants... www.climatespectator.com.au/commentary/should-sa-fear-closure-coal-power
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Post by anonposter on Feb 12, 2013 20:13:23 GMT 9.5
The Price Reduction isn't factored into consumer bills because it isn't actually real, in fact it costs more and the consumer has to pay more because of it (why does Germany have such expensive power?). We've gone over this before. wind plants might even have a higher capacity factor than old coal plants... The best wind power plants get 40% and that is very rare with 30% being more typical, in Europe it is often worse than 20%. If you have a coal plant that isn't making at least 50% then you need to ask some serious questions about the operation of the plant. One other advantage coal has over wind is that the times when it is running are decided by the grid operator, that's why a 40% capacity factor for a coal plant is actually better than a 40% capacity factor with a wind farm.
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Post by David B. Benson on Feb 13, 2013 7:41:17 GMT 9.5
Best to distinguish availability and capacity. The capacity cannot be larger than the availability but can readily be less. The availability factor of old coal plants is probably greater than 85% but because such are inefficient and so rarely used the capacity factor might be only 20%.
Typically wind farms are on a must take basis so the capacity factor equals the availability factor. In Spain wind producers are not quite must take and the capacity factor is about 3--5% less than the maximum, the availability factor of around 25--30%.
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Post by proteos on Feb 19, 2013 20:57:08 GMT 9.5
and back up will often come from old plants (so we do not need to factor in construction costs) or gas plants, which were build under optimistic assumptions. (gas plants build today as base power plants will do nothing but reserve duty for the majority of their life time) as the article in original post mentions, the future is indeed looking grim for coal. The future is not grim for coal everywhere at today's price. In the EU, gas is much more expansive than gas, and for old plants, it's just the marginal cost (~fuel cost) that matters. That's the huge problem when changing the electrical system. Without a meaningful carbon cost, coal is here to stay. To give an example, coal plant are only closing now in France, 40 years after the start of the nuclear programme. Some have run for 50 years, their use has changed from baseload to "half base" or "semi peak". It is only now that have aged too much to be able to respect the EU directive that they will close and be replaced by (most of the time) gas or (from time to time) german coal-generated imports. If you want to expel coal from the electricity generation, you must use one of these ways: - overwhelming build of powerplants that displace most of electricity generation towards a low marginal cost means. That's what Denmark and Germany are failing to do: 25% of production is not enough
- Price carbon emission agressively (i.e not 5€/tonne but more like 30-50€/tonne)
- Find a cheap source of gas
- Enact punishing anti-pollution regulations (might not work!)
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Post by jagdish on Feb 23, 2013 11:26:35 GMT 9.5
Renewables/unreliables were the energy source in the pre-industrial world. Suitable niches can still be found where three conditions can be met:- a. Places away from power grid where it would be uneconomical to extend them. b. Adequate storage for the time when the wind is not blowing and the sun is not shining. c. A different low cost technology. The wind can be used for mechanical purposes by not going the electrical route and storing the energy as compressed air and using pneumatic technology. More efficient technology continues to be developed for conversion of sunlight to electrical energy and battery storage. This can be used in a 12V DC system for efficient CFL lighting and electronic use in radio, TV and computers. More of direct use of sunlight can be made in heating of water and cooking, besides existing uses.
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Post by anonposter on Feb 23, 2013 12:51:55 GMT 9.5
Renewables/unreliables were the energy source in the pre-industrial world. Suitable niches can still be found where three conditions can be met:- a. Places away from power grid where it would be uneconomical to extend them. b. Adequate storage for the time when the wind is not blowing and the sun is not shining. c. A different low cost technology. I would have added where reliability doesn't really matter (in many cases it'd be as a supplement to a more reliable source, e.g. solar hot water, the one use of solar power that actually makes sense). The wind can be used for mechanical purposes by not going the electrical route and storing the energy as compressed air and using pneumatic technology. Compressed air is about the most expensive energy source out there so no, that's not such a good idea. More efficient technology continues to be developed for conversion of sunlight to electrical energy and battery storage. Not really, we're pretty much at the efficiency limits of solar power (sure, we could do a bit better, but PV development is more focused on lower cost at the expense of efficiency).
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Post by edireland on Feb 23, 2013 17:07:22 GMT 9.5
The only way to get much higher efficiency from solar cells is to go for nantennas.
We haven't quite been able to make those yet.... although 90% efficiency with no rare materials in the array sounds rather game changing....
As to grid extension costs making it possible to have places where solar is cheaper than the alternatives... the places where this can happen are shrinking fast thanks to reductions in costs for things like 'HVDC Light'.
In theory most of these places are close enough to a heavily populated area to be coupled into a grid, and I believe that is what will happen in the future.
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Post by sod on Mar 5, 2013 6:52:28 GMT 9.5
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Post by edireland on Mar 5, 2013 10:43:10 GMT 9.5
You can have very hot and humid conditions under a rather dull sky.....
And in Ibiza I recall air conditioning loads being rather significant 24 hours a day during the summer, and solar is not available during the night.
India's grid is almost nonexistant on a national scale with huge fractions of thepopulation having no grid access, it is hardly representative of the western world.
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Post by David B. Benson on Mar 15, 2013 13:13:54 GMT 9.5
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Post by sod on Mar 17, 2013 18:21:56 GMT 9.5
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Post by anonposter on Mar 17, 2013 22:28:38 GMT 9.5
When these constructions end in a decade, they will be up against fierce competition with cheaper renewables. If the public still buys the renewable scam, remove the subsidies and solar and wind are gone. These nuclear power plants will have trouble selling power during summer daytime at all! Only if solar gets subsidised (and takes up an excessive amount of generating capacity, nuclear reactors will undercut fossil fuels on marginal cost and that is what determines which generators get used).
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Post by edireland on Mar 18, 2013 12:31:45 GMT 9.5
When these constructions end in a decade, they will be up against fierce competition with cheaper renewables. These nuclear power plants will have trouble selling power during summer daytime at all! Only because solar and wind turbine operators have managed to obtain a "must take" priveledge that requires any power they have at any time to be purchased no matter the operational issues. Firstly "3.3GWe of capacity in 2012" equates to about 330MWe average capacity. This means Solar has been built with a capacity equal to constructing one ESBWR every 5 years. This is not really that impressive. Additionally if you actually read that article about the Corps of Engineers solar farm, you woudl note that the electricity is only cheaper than grid power because of the tax credit they recieved for building it. In other words the Department of Energy budget is being used to reduce the expenditure of the Department of Defence.
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Post by jagdish on Mar 26, 2013 15:37:32 GMT 9.5
The costs are given at the time and place of generation. It is the shift to the place and time of use that makes the difference. In case of nuclear you can shift the place by a transmission line. In case of wind and solar, the need for storage to shift the time is so critical that you have to give it priority. It should be generated at the place of use like the roof-top panels. It can then be stored for use. It can serve the rural niche.
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Post by edireland on Mar 26, 2013 18:12:12 GMT 9.5
There is no real "rural niche" anywhere that consumes large amounts of electricity.
Advances in power transport technologies have seen to that.
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Post by David B. Benson on Apr 5, 2013 14:50:11 GMT 9.5
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Post by David B. Benson on Apr 6, 2013 11:51:50 GMT 9.5
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Post by David B. Benson on Apr 11, 2013 14:00:43 GMT 9.5
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Post by Nuclear on Apr 12, 2013 0:05:45 GMT 9.5
In some regions, the plant-level levelised cost of electricity for wind turbines is competitive with that of natural gas generators at high gas prices.
Adding wind to an energy mix dominated by natural gas makes sense if good wind resources are available and gas prices climb past a certain level.
Thanks to fracking, gas prices in the US have hit a new low and soon, natural gas will be the largest primary energy source used in the electricity sector. But gas prices will likely increase in the coming decades, giving wind a chance to compete without the aid subsidies. The advantage of wind over nuclear is that it can be added to the grid incrementally, which reduces investor risk compared to huge single projects like nuclear power plants which are prone to cost and schedule overruns.
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