Printable View
In today's news there is an article about relieving fixed export limits for solar panels to the grid.
World-first flexible export limits are coming to rooftop solar. Here'''s how they work - ABC News
This is the kind of simple but brilliant tech that will get us there. Flooding the grid apparently only happens around 2 % of the time, or something ridiculously small, so until now the whole system gets choked down all the time and solar generated power is just being wasted.
Nicely spotted, FF.
That problem must be particularly accute in South Australia because they source such a high percentage of their electricity from renewables - an incredible 66% from solar and wind. On a windy, sunny day the overloads must be incredible.
Tasmania is over 99% renewables - 80% hydro and 20% solar plus wind. The other states are lagging.
Attachment 523739
Western Australia still generates around 85% of its electricity from fossil fuels - only 15% from renewables - solar + wind. Silly me, I thought WA was sunny!
Thanks FFQuote:
Originally Posted by FenceFurniture
The "flooding " of the grid only happens occasionally during low demand periods coupled with high wind and solar generation. It is true to say that at this stage of the game only SA has the capacity to supply it's electrical demand with 100% renewables: But only rarely. Really there should be an emphasis on facilities to store the surplus energy and that is the area that requires the most attention.
Regards
Paul
Graeme
Those are interesting statistics you have posted. However, while true in some regards they may be a little mis-misleading in others. I am in no way suggesting that was your intention. However, a couple of comments would be:
1. Although SA has the highest percentage of renewables, it is the percentage of their demand, which is the smallest of all the states excepting Tasmania. However, Tassie is only a little smaller. I think QLD has the highest percentage of renewables, but with a demand averaging around three times that of SA the percentage is well down based on that demand figure.
2. The split for SA only indicates renewables and gas. What happened to the 500MW interconnector from Victoria where the predominance is brown coal? Without that interconnector SA would be down the gurgler.
I imagine that somewhere in the fine print of those stats there is a reference to daytime consumption or some other qualification.
Regards
Paul
Hi Paul
That bar chart was produced by the Federal Department of Climate Change, Energy, the Environment and Water - what a mouthful - in April last year. Hopefully, it will be updated next month? The chart depicts electricity produced in each state and territory - it does not say anything about transfers or ultimate consumption.
My understanding of the "grid overload" or "flooding" problem is that grid-wide it is an infrequent issue. However, at the micro level, it is quite a common occurence. Small geographic areas may be sunny and windy and produce excess electricity and that sector of the grid gets overloaded faster that the energy can be transferred elsewhere. Essentailly, the grid is set up to transfer electricity into suburbs, not out, but that a process of adaptation is underway.
I do not understand your comment about Queensland. According to the DCCEEW bar chart, Western Australia is the only state that produces a lower percentage of its electricity from renewables than Queensland.
Who names government departments? I can remember one and two word names.
The thing that struck me about the bar chart is how different the sourcing of electricity is between the states.
Wait to see what happens when liddle power station shuts down next month
Theres 900mw out of the grid.
GraemeQuote:
Originally Posted by GraemeCook
I think the percentage relates to the individual state generation. Therefore SA may be able to supply, at times, 100% of a low demand. Say 1500MW. So assume they have a 1500MW capability. QLD may also be able to deliver 1500MW but as a percentage of a 6000MW demand that would only show up as 25% on the bar chart. If QLD can supply 2200MW of renewables they would clearly have more capability than SA but as a percentage of demand it doesn't look as good.
Now, don't take my figures as precise, because they most certainly are not. I chose those figures to make the sums easy. However, I think it makes the point and hence my early comment about who produces the most.
Regards
Paul
HABQuote:
Originally Posted by havabeer69
We may see the two interconnectors from QLD to NSW running hot for quite a while!
Regards
Paul
We already have a flexible limit designed into every inverter which will throttle your export as the grid voltage rises and cut off your export at 255v. For most people in suburbs with lots of solar this happens every day during peak solar generation and for a lot of rural properties as well. The problem is the grid was never designed for rooftop solar and limiting export to 5kw is the only way to have equity. In fact the solar generation is so great during the day that generators are quite often paying for people to take the excess supply.Quote:
Originally Posted by FenceFurniture
We can never get to 80% renewable or even 50% without a massive investment in the grid infrastructure.
Well, reducing the number of "nookelar" submarines ordered by one single unit should be enough to cover the "massive investment in the grid infrastructure" and wouldn't take 20 or 30 years to start seeing a difference....!!Quote:
Originally Posted by Nutz
Totally agree, we got fleeced on the sub deals. Countries thrive or die on the cost of energy and the only countries that are lowering their energy costs are China and Russia. Mind you China holds third world status so is not required to meet any future emissions targets and will likely receive "compensation" from countries like Australia.Quote:
Originally Posted by yvan
I can recall only one blackout this year but that is likely to change for the worst very soon. Imagine running a company and the power goes out, 0 productivity but same labour cost. These are the real issues facing EU countries right now and Australia is walking straight into the same.
haveabeer mentioned in post #1026 that Liddell would be shutting down in April. It appears that the date is 28 April. This article tries to explain some of what has been happening:
‘It can’t be left to the market’: the closure of the Liddell power station and the uncertainty of the future (msn.com)
A few comments would be that Liddell is indeed at the end of it's life. In fact I was there for about 18 months around 1985 and it might have been argued that the end was nigh even back then. It is remarkable that it has lasted even this long.
For some time only three of the four units have been operating. The fourth unit was probably a spare parts store. Of the three remaining units all have been de-rated from their nominal 500MW capacity down to 320MW and in practice rarely supply much more than 300MW. Consequently the effective loss to the national grid when Liddell shuts its doors is about that 900MW mark: Not good, but not quite as bad as the 2000MW of the halcyon years.
The main problem now is that the strategies AGL were putting forward to pick up the slack and pacify opposition appear to have hit the first two or three hurdles. Some have been chopped completely, others have not really progressed and are truthfully a long way off. The other aspect to which we have to be wary is when the figures are trotted out. For example, there was talk of a 500MW battery ( this is one of the projects that has not progressed) as if that would replace a 500MW coal fired unit. Assuming that the battery is rated for one hour, which is not an unreasonable assumption based on what is typically available, replacement of the fossil fired unit, and fossil is so appropriate in this instance, would require 24 batteries of 500MW!
I read on to the concerns of the local communities as eventually power stations and coal mines begin to be phased out in the Hunter region. The COO, who hails from Dusseldorf, said that their were thousands of templates for absorbing the change. Hmm...Maybe, but I wasn't completely reassured by this statement when he continued by saying that Australia was not an island. I think he has a different Atlas to me.
I know that communities do adjust when industry is removed, but to suggest that it is easy, that there are many opportunities and that it is not without pain is a lie. It is always galling in the extreme when a person who is probably well placed in the community as far as finances go glibly implies that everything will be OK. Rubbish. There will be a mile of hurt. The time to prepare is right now.
Communities adjust, because they are forced to adjust.
Regards
Paul
Déjà vu, California, all over again.
Shall we consider one scenario:
AGL closes Liddel on schedule; the Greenies applaud, all that nasty coal fire pollution removed from the atmosphere, and 900 MW electricity removed from the supply chain.
But, as Paul says, little effective planning has occured to replace that 900MW. Peak hour wholesale electricity prices will soar due to "market forces". Electricity demand in the short to medium term is notoriously inelastic - people do not switch off the lights when prices rise.
And AGL will be ready to supply a reduced amount of electricity from their other plants at substantially higher prices. It is all due to "market forces". AGL would not manipulate the market.
Surely AGL would not be that cynical?
Surely I am not being cynical?
Surely, our politicians could not be that stupid?
I have repeatedly, and somewhat boringly, trotted out the mantra that there is no power source today that does not have at least one fundamental flaw or in some instances several fundamental flaws. I think nuclear may fall into this second category.
This is a little demolition job on the nuclear option:
Disarming the persistent myths of a glowing nuclear renaissance (msn.com)
One of the flaws in any proposal, electrical or otherwise, is assuming that everything will go just fine. This is often far from the truth as this castigation implies.
Regards
Paul
All true, as long as you can outsource all manufacturing to some 'friendly' nation.Quote:
Originally Posted by Bushmiller