Sunny Thoughts

Clear the thread ! Long train coming through ................ toot toot !!! :-))

Yeah, sorry. What was missing is the simple fact that energy from whatever generation type is storable in batteries. The spin on a lot of stories is that only 'green' electrons can .... one has to be careful to separate out the technology from the hubris about the technology ! However well intended. :-)

Yup, the simple physics is Energy = mass * g * height of fall/rise. Water is close enough to one kilogram per litre, g is close enough to ten thus we have 10 Joules per litre of water per vertical metre.

{ One Joule may be defined here as the energy given/taken when a force of one Newton is applied over one metre. For example 10 Megalitres of water up one metre will be 100 MJ stored, the same amount going up 100m will be 10 GigaJoule. The time rate of charge/discharge is (mega)Watts as usual, so one GJ if transacted in 100 secs will be at 10MW. Etc. }

This of course ignores all the dissipative aspects so one needs to account for them ( per installation ) to get available/useful energy. You lose on the pump-up as well as the fall-down. But electric batteries have this too. If you like hydro schemes do have the equivalents of internal resistance etc. It is reasonable to think of the fall/rise height as like voltage, time rate of volumes ( ie. bulk water flow ) as like current. I wouldn't confuse matters by trying to find inductance/capacitance analogs, but one probably could. Let's stay with a DC model for our water storage. :-)

Dams are landscape altering and thus collide with many public issues outside of energy management.

Dams have a huge on-cost and far lower maintenance. Construction and usage are well beyond current public policy timelines.

The tension is between micro vs macro grids ie. what is the physical scale encompassed by an arc involving generation -> storage -> usage. This thread started because I wanted to do all of that on my modest residential block ( 0.9 acre ). There are many other models which differ in that scale. Alas this goes beyond technical points as the supply side is largely monopolistic or at least cartel dominated : despite contrary reports the market acts 'as if' interior knowledge is being exchanged and Occam's razor on that says guess what ? :-)))

Well we have a massive interior desert where only the hardy survive ! But you are correct, the Great Dividing range forms the precipitation trigger that benefits the coastal side and corresponding rain shadows that prejudices the inland side. This indeed was the logic of the Snowy Mountain scheme : to divert flow inland that would have gone to the eastern ocean. Hence the irrigation belt down the Murray River through to South Australia and into the Bight instead. We wouldn't have those lovely Barossa wines otherwise ! The hydroelectric component was a lesser motivation compared with enabling cropping where only seasonal pastoral use would persist.

{ I've found a great background source on the hydrology of SE Australia : Nature's Line. This is the story of George Goyder, a government surveyor ~ 150 years ago. You can tease out true long term trends as measured from much modern speculation that has no observational support. In effect he discovered the El-Nino/La-Nina oscillation that dominates land use cycles here. He defined a line on the map which would reliably separate those lands for which agriculture could sustain populations vs. boom/bust pastoral leases. We now call it Goyder's Line. All of his assertions remain true today. }

On paper that's a great idea. The present reality is finding any willing private enterprise that will be a co-party to a contract with extant governments down this way. Without getting into messy political detail the commercial imperative is to avoid legislative risk, that being the ability of the sovereign entity to totally re-define the entire basis of the transaction by suitable retrospective legislation. That includes all terms, especially price, and long after contract agreement. The example I have in mind involved an over $1 billion AUD loss. Repudiation of sovereign debt, or threat of it as a negotiating tactic, has now been normalised. Two out of the three major civil contractors ( capable of immense works ) in this country were burnt badly and have literally left the state. They were forced to settle for much less than the actual tort against them, and keep quiet to boot. For another ( human ) generation I reckon all such matters would have to be cash in advance of works strictly. Sad but true. This will close the option of amortising construction costs over very many budget cycles which is the typical method for this category of public works.

See above. While these issues are interesting, they are of minor rank in importance compared to simply honoring a well conceived contract. It really has descended that far. It is notable that for the SA battery scheme all major providers are foreign. This is not just a matter of technical expertise or production capacity, the locals simply wouldn't touch it with a barge pole. :-((((

The greatest difficulty in SA was micromanagement by political entities of technical matters. That has been the prime determinant of the present situation and thus driving historically revisionist narratives offered now ie. what has been left out of the discussion. Last year's storm simply revealed the actual quality of the projects. My kindest remark could be that they moved too far and too soon, and are now ideologically trapped and won't even partially row back. Human pride ultimately. Visionary is one of those ambiguous adjectives. It could mean an Einstein-like once-per-millennium intellect or a total fool with his head up his own colon. Can one see for light years or only a few centimetres ? Go on. Guess which I think applies here .... :-)))))

Cheers, Mike.

( edit ) Caboose : Don't I pontificate ? A bit. I was once semi-offered a run for parliament. My reply was that my only good work within government chambers would be with an automatic weapon. A decade later that remark isn't quite so funny though .... nor has the offer been revisited. They may have thought I really meant it. Either way it was a hostile response to the proposal ..... like I care to be a member of that club. LOL. :-)))