High voltage direct current transmission lines have lower losses than AC ones, are especially suitable for submarine cables, and the AC converters can actually improve the stability of the grid due to the nature of the converters.
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High-voltage direct current - Wikipedia, the free encyclopedia
why not just this?
Thorium: Cleaner Nuclear Power? - Power Technology
Spot on, and not many people understand this. PV systems are reaching saturation point in suburban Australia, and this is one of the reasons the Government have cut it back recently. I'll try to explain...Quote:
Originally Posted by rovercare
Think of a residential street that has maybe 5 or 6 decent PV systems installed. There are plenty of examples of this around the country, and most of you will have seen such a street. Now, imagine on a bright sunny day (doesn't have to be hot - this actually reduces the effeciancy of a PV cell) everyone has breakfast and goes to work, thinking how much power they are putting back into the grid. When they get home, they discover that they have only put back 1 to 2 KWH when they were thinking they should have done more like 7 to 10 - what's going on they ask?
Not many people are aware of how the grid works, and what it's limitations are, or how a PV system puts power back into the grid. Basically the inverter at the house needs to push the voltage up to load its power back into the grid. But, once everyone has gone to work, and the load is low in the area, the voltage in that area will rise. Add a few PV inverters trying to squeeze more power in there by upping the voltage, and very soon, the inverters have reached the max voltage they can legally put out, so they stop or slow right down, and you find you have 250 volts at your power points.
PV systems aren't a magic bullet, I don't know what is, but while we continue to distribute power like we currently do, these sort of localised solutions are just a stop gap...
Regards - Gav
Thorium is promising, but there are a few issues with it, namely associated with fuel fabrication and spent fuel treatment. Thorium has a very high melting point, so this makes fuel fabrication very difficult and expensive.
PV is not really a good solution, as mentioned they do cause grid issues and the average one is only about 8% efficient, atrocious when compared to solar thermal and geothermal.
It's a bugger that, slowed down my installing to almost a halt:(Quote:
Originally Posted by bacicat2000
Yes, stop gap measure.... Mind you, I just put 18 extra panels on my shed, to make the most of the free government money:D
I'll go to 10kw total allowed when parity to the feed in tariff comes closer...
HRL are trying for a cleaner coal plant, but keep getting held up as Boone wants to rock the green boat, loy yang b should of been finished around 1990, the driffield, then Flynn, nothing much has happened aside from some piddly gas turbines, we are far behind where we should of been in modern base load generation, let alone green alternatives, considering these plants would of been 30 years newer, it wouldn't of been such an issue
Im waiting for the nuclear plant following the desalination plant:angel:
Also grid voltage is legally bound to 230v +10%, problem is if they change tappings to suit, voltage plummets when it's dark or cloudy and the antiquated regs can't keep up, apparently it's a huge issue around mallacoota
Anyhow, there is lots of aspects people don't know about, also which has failed to further advance again
The best solution, at least for Victoria is to build some more dams and utilise hydro-electric generation. What's that, increase water storage as well, building for the future? The Greens wont have it, and its political suicide to suggest it.
I'd like to see the dams to replace 6500MW, might need a snorkel:DQuote:
Originally Posted by hgsuzuki
I have read quite a lot of the document and offer the following.
My overriding concern is that the proposal inhibits personal liberty so much that it will never be politically acceptable.
NO petrol driven transport in ten years? Come on. How will these great electric trains and electric trucks provide goods and services outside the most populated areas?
Are we all willing to not have a single petrol/diesel driven car when we have to drive several hundred kilometers and camp in some out of the way place without a charging plug nearby?
I have major arguments with many of the assumptions used
probably going backwards since I put the objections on post its
Figure 2.4 showing a decline in oil /gas production.
I have seen this same graph showing a future decline but starting in 1980, when I was first briefed by Minerals and Energy as a trade Commissioner. It was BS then and is BS now as oil/gas companies never firm up reserves more than about 5 years out and report only comfirmed reserves to the gummmt.
The report Absolutely glosses over what they call "balancing power" which is power needed for a network when the wind doesn't blow and the sun doesn't shine.
"Variabilty can be future managed by adjusting the demand curve through the supply side scheduling ofspace and watt pump loads."
In understandable language this means they will turn off everyone's fancy reverse cycle air conditioning as they see fit say on a -5 day in Victoria if they start to run out of power , as they no longer have any gas or coal generating to fall back on. And of course turn off all the electric car chargers.
That will be popular!
The report makes comparisons with Germany and observes that Australia uses more power per capita.
One of the reasons for this is that it takes considerably more power to cool than to heat,and a major reason that summer is peak usage time in Australia. This is one reson greenhouses are more efficient in cooler countries than in hot countries.
I really like the $420 per household asumption. remember this is AFTER we all have smart meters and can only afford to use our dryers and dishwashers after 11PM at night.
So even after everyone changes their behaviour to try and reduce their bills they still pay 25% to maybe 50% more.
There does not seem to be any discussions of the network costs of all this. They claim wind will work better here than Denmark as they give a utilisation of 30% in Australia when Denmark gets 25% and is generally acknowledged as the windiest place in the World. AND in Denmark they get about only 11% utilisation in July.
But if the plan is to disperse wind generators all along the coast the networks will have to have immense sums spent.
This is ironic when it appears to have never been cost effective to build a distributor from Ord River to Darwin and use the free hydroelectric potential.
I wish that the dream could become reality, and we will hopefully see rational development, but IMHO the real stumbling blocks for this proposal are the presumption of technology and emissions are so much more important than human freedom.
Will you accept ONLY having an electric car (at what price by the way?)
Will you accept having the switching of your electrical appliances especially heating /cooling remotely switched , based on the whim of some bureaucrat who decides to load shed because the system cannot cope.
I also think the assumptions for many of the solar and wind capacities are very optomistic based on current experience. In 2000 Angela Merkel promised to shut down every German nuclear power staion by 2010. I think most are still operating. AFAIR The Danish Government promised to shut down most of their 4 Coal fired plants. AFAIK all are still operating.
Oh and I love the biomass bit. I was involved in a stillborn study to measure the biomass available in NSW . One of the assumption then about biomass was that farmers would give it away to the government. But hey I only had to talk to a few farmers and groups to find that biomass has a value and that there wasn't much available anyway since the advent of minimum till and zero till ( particularly wheat which the report targets). Rice growers burn theirs to reinput soil nutrients and would demand a considerable price. Yet another pie in the sky.
Regards Philip A
That's a touchy subject to those that live down that way... Mallacoota is supplied out of the Newmerella Zone sub, and is at the end of 150KM of 22KV feeder that looks like a piece of wet string in places. The regs chase each other at times, and the lights in the houses go up and down like a disco...Quote:
Originally Posted by rovercare
Charlton is another place that struggles. The 66KV radial line is a bit wimpy and on hot days the regulation of the 66 up there struggles. This will probably be fixed in a year or 2 when they cut in the next bit of reconductored line.
Somebody else mentioned wind - great while it is blowing. You only need to look at what happened on Phillip Island a couple of years ago on New Years Eve - stinking hot night, and no wind. The small wind farm at Wonthaggi was doing nothing, and the whole grid went down... If the same conditions happen again this year, the result will be the same. There were some large gensets in the Zone sub there over Christmas for a couple of years, but alas, no money for that this year, so anyone heading down that way between Christmas and new year will need to hope there is a breeze...