Results 1,726 to 1,740 of 2079
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16th December 2023, 02:40 PM #1726
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16th December 2023, 02:49 PM #1727
Paul
my point was that until we had "advanced" to the stage where we could reliably measure the temperature at multiple points across the entire planet -- which required the appropriate satellite mounted sensors -- any temperature comparison was essentially worthless.
Prior to that sea surface temperatures -- "sea surface temperature" requiring that the water having a thermometer stuck into it be collected from 2 or 3 fathoms (12 to 18 feet) below the surface -- were reported, at best, on an ad hoc basis. While there were lots of sea surface measurements from the North Atlantic, other sea routes were less frequently sampled, and whole swathes of the ocean were only sampled as part of scientific exhibitions.
Warb
as recently(!) 540 million years ago (which is less than 12% of the earth's age) the earth is thought to have gone though its most recent "snow ball" phase, where almost all of the planet froze.
so there is geological evidence that the earth was once very much colder than at present.
As far as I know, the only reputable scientists who think that the earth will "survive" its current heating phase are geologists.
But given the time scales geologists work with, and their general view that modern civilisation is less than the blink of an eye on the geological time scale, their definition of "survivable" is somewhat foreign to those of us who are living with the daily reminders of temperature.regards from Alberta, Canada
ian
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16th December 2023, 02:54 PM #1728Originally Posted by Bushmiller
One of the things that I am becoming increasingly aware of is that all the currently available alternative sources - hydro, pumped hydro and even nuclear - all have lead times of at least ten years. With the increasing escalation of solar and wind power, I am not sure we have ten years before grid instability reaches an implosion point.
Also I am starting to have doubts about the real viability of pumped hydro. This is not just a reaction to the Snowy 2 cost hikes. I would love to see the feasibility studies!
* It takes a lot of energy to pump water up hill, a hell of a lot if that hill is a mountain,
* Is there a better use for that energy elsewhere?
* Why not just build a second hydro scheme - if you have the topography and rainfall.
EDIT: I have edited the embolded sentence. Bill Gate's auto-correct feature changed the phrase "grid instability" to read "grid installation" which is nonsensical.
I think that grid instability is developing into the major issue.
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16th December 2023, 03:02 PM #1729Originally Posted by Warb
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16th December 2023, 03:03 PM #1730Senior Member
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16th December 2023, 03:17 PM #1731
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16th December 2023, 04:01 PM #1732Senior Member
- Join Date
- Apr 2010
- Location
- NSW, but near Canberra
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Only if we assume the required changes don't involve "us" making changes directly. The generation, storage and transmission of power are controlled by the government and large corporations, but the usage of power is largely controlled by "us". How much less power would we use, and therefore how much less generation and storage would we require, if we put a bit of thought and the tiniest amount of effort into using less?
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16th December 2023, 05:27 PM #1733
Previously I said I would look for all the data on Katoomba and then break it into 10 year periods. A few caveats on those records:
- The BOM records start in 1907, but there are two enormous gaps. There are no records from 1942 to 1956 (15 years!), and none from May 1967 to June 1973.
- For the sake of completeness I have substituted the monthly mean temps into one 6 month period, and one other month, which were all blank.
- Looking at 10 year periods where possible allows some chance of evening out an El Niño or La Niña effect, e.g. 1978 was 15.4° but only 2 years later 1980 was 17.7°.
All of the following only refers to Katoomba.
1984–93 was 16.1°
2014–23 was 18.1°
As I posted before, 2023 will be hotter than the previous hottest year (1957 at 18.9°). Probably it will be in the range 19.1 to 19.3°
I charted the Mean° for the decades (as described in the charts), and then split that into the 6 warmer months and the 6 cooler months to see what differences it might show: nil difference whatsoever in recent decades (from 1984). That is, there is 2.0° difference between 1984-90 and 2014-23 for the overall temps, the warmer months, and the cooler months.
Kat decades temps.JPG
If we accept that more accurate records started to be kept from about 1980, the trend is quite alarming at 2.0° in just 40 years.
Notes:
- I had to slightly fudge the charts to ensure that the temp scales were all the same scale - some weird Excel thing going on.
- The first period 1907-1911 was, ahem, a "short" decade!
- The periods can be seen on the amber chart (for the warmer months).
- The last plot on the right is for 2023 only, and you can see a distinct up-tick due to the crazy temps we had in July-Sept.
- It looks to me like the warmer month temperatures are probably higher than reality between 1912 and the 1970s. There is quite a hump and a prominent "V" which seems unlikely, given that I am using 10-year periods. The cooler months chart is a bit more realistic, I think.
Some other points to note:
- 6 of the monthly records for the hottest months on record have all occurred in the last 6 years. These were the months of Jan, Apr, May in 2018, and Jul, Aug, Sep in 2023
- 3 of the monthly records for the hottest months on record occurred in 1957 (Jun, Nov, Dec) and it was the previous hottest year at 18.9° until 2023 which will be 19.1° or more)
- The Feb and Mar records were set in 1939 and 1940 respectively.
- The Oct record was set in 2014.
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16th December 2023, 05:30 PM #1734
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16th December 2023, 05:34 PM #1735
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16th December 2023, 06:22 PM #1736
Hi Graeme
to answer your implied questions ...
I've said before that Snowy 2.0, might be better described as Snowy 20 -- as in it's expected cost is 20 BILLION
Yes, it does take considerable energy to pump water uphill, but the energy cost is approximately the same for every 100 metres of head you achieve. Actually it might cost more in energy terms to pump water 100 metres up a small hill than to pump it to the same elevation gain up a mountain. The friction loss in the longer pipe or tunnel up the "hill" would likely be the major contributor to the additional cost.
Is there a better use of energy elsewhere? I'm thinking NO. In essence pumped hydro is just a long discharge battery. On those days when electricity generated from roof top solar leads to wind and solar farm electricity being "switched to idle", Snowy 20 will be able to use that reserve electricity to pump water uphill. Something within the chemistry of current battery technology limits the draw-down time to something like 4 hours regardless of the battery's total MWh capacity. Snowy 20 is designed to deliver power for several days.
However, there is another source of longish term battery storage and that is Australia's aluminium smelters. The molten aluminium pot lines within those smelters are very hot and if we could capture the IR radiation from them, they could become useful as GWh batteries. Capturing IR radiation has been done at laboratory scale with efficiencies around 2x that of regular solar panels. The beauty of this approach is that the high capacity feeder lines and transformers are largely in place.
I really like your optimism around building a second Snowy scale hydro scheme. The original Snowy Scheme essentially captured all the NSW snow melt and similar dams in Victoria's high country capture the bulk of the rest of the snow melt.
Tassie is pretty much built-out hydro wise -- I highly doubt that you would be able to get environmental approval to construct another dam, let alone concurrence from the Greens.
Which just leaves the rivers of Queensland's tropical north. Apart from the challenge of getting the electricity from FNQ to Sydney, there is the small challenge of obtaining environmental approval, not to mention First Nations and Greens by-in.regards from Alberta, Canada
ian
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16th December 2023, 06:38 PM #1737
FF De-commissioning is almost never talked about. In fact I had never really considered the implications until BobL alerted me to this way back in the depths of this thread. You can't just demolish them and haul the steel off to the recyclers, because the so much material is contaminated. I don't pretend to know all the implications of de-commissioning a nuke, but it is no walk in the park. There are quite a few nukes past their use by dates, but I have no information as to how the owners are coping with that issue.
Regards
PaulBushmiller;
"Power tends to corrupt. Absolute power corrupts, absolutely!"
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16th December 2023, 07:05 PM #1738
As a small exercise and because almost everybody else seems to be climbing on the statistical bandwagon (Only joking - I very much appreciate all the time and research that people have made), I went back to see the incidence of negative pricing during the day on the wholesale market. This was just for QLD and it probably is the worst situation from that point of. The other states not too far behind.
Please note that this negative pricing only applies to the spot market and I estimate the spot market could be as little as 25% of the total. The spot market varies in size while the contracts are inflexible. That 25% might be the case during the day, but for the evening peak it could represent a much larger slice. Perhaps 35% or 40%.
I went back until 13 June. During that time the daytime prices were negative most days, although for varying periods of time. There were only 9 days when the price did not go negative at some point. 5 of those days the minimum price was $0.00. 2 days were $1.00, 1 day was $7.00 (still nowhere near a viable level for generators as it doesn't even pay for the fuel) and the only day where it may just have been a viable price point it reached $39.00. That would not have been economic for everybody.
I am mentioning this to illustrate the difficulties a fossil powered station encounters. Solar, Wind and Hydro simply shut down, but of course they still don't make any money. Actually, the situation is still not that simple, but I am not at liberty to divulge more information there and every station will be different.
If the power generators can't make enough money during the night to cover their losses through the day, they are history. That is the problem looming and the one the government of the day is not tackling. The previous government was disgraceful in that regard and the current government does not appear to have done much to head us in the right direction either. maybe they think it will fix itself.
Regards
PaulBushmiller;
"Power tends to corrupt. Absolute power corrupts, absolutely!"
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17th December 2023, 04:16 AM #1739
I'll say watch this space -- my prediction is that when the lights start going out on consecutive hot days, governments (state and/or federal) will step in and prop the power generators up with non-recourse loans, designated as "commercial-in-confidence".
Given the quantum of cash the previous federal government gifted major corporations during Covid -- cash which ultimately ended up in the hands of their owners -- I have little doubt similar (up to full nationalisation) arrangements will apply. It's a classic case of privatise the profit, draw on the public purse for the losses.
As to the direction being taken by the current government, my understanding is that the current government has undertaken to underwrite -- a.k.a. take on the ultimate liability -- so that the private businesses proposing to purchase grid scale batteries can obtain bank loans at market rates. Which is a step in the "right" direction.regards from Alberta, Canada
ian
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17th December 2023, 12:19 PM #1740
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