Future of the Australian Electricity Market

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Originally Posted by ian

LG(?) was done for having fridges and freezers that would measure the ambient environmental temperature and thus determine if the device was being subjected to a Standards' compliance test and lower the fridge/freezer's power consumption accordingly to obtain a better star rating.

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Oooo, they "did a Volkswagen". :)


I did a little reading on the historical reasons for voltages, amperages, frequency, etc last night.

I'd hoped for a really good scientific basis, solid with engineering, intelligent consideration and logic.

But, nay. It is a compromise of a compromise of a hack, of a competing system stolen off an inventor and its all arbitrary and all rather MESSY and disappointing.

Most of it is based on 1890's tech, such as filament lightbulb flicker, abilities of materials at the time, minimisation of public panic ("oh! The Vapours!") and sheer bastardry.

Bummer hey!

I'd hoped the numbers of 10/20 amps, 50/60hz, 120/240/360 volts and 2/3/4 wire distro were all rather neat science to do with neatness of circles and such. SO DISAPOINTING! :)

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Originally Posted by woodPixel

I'd hoped the numbers of 10/20 amps, 50/60hz, 120/240/360 volts and 2/3/4 wire distro were all rather neat science to do with neatness of circles and such. SO DISAPOINTING! :)

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Electrical distribution systems are a bit like the railway gauges. Once they are set up they are very hard to change.
The problem is that initially every engineer had their own idea of what was right and in the early days in some US cities the systems changed between city blocks.

Electrical quantities used these days are more or less chosen for a balance of practical purposes.

Let's start by looking at something as the energy requirement for boiling 2L of water.
You can can boil it quickly but you need high current and or high voltage - unsafe.
Too low a current/voltage and it will take too long.

10A at 240V = 2400W = 2400 Joules/second
To raise the temp of 1g of water by 1ºC takes 4.2 Joules
To raise the temp of 2000g of water by say 80ºC = 2000 x 80 x 4.2 = 672000 J
Divide that by 2400 = 280s or about 5 minutes (it turns out in practice to be a bit more because of heat losses.

Would you be prepared to be safer and for it to take 20 minutes? or would you be prepared to risk electrocution and go for 2 minutes?
Higher V would require much better/expensive insulation and protection mechanisms.

240V compared to 110V is interesting.
110V means less likely to get electrocuted
BUT
It means greater currents have to be used, so thicker wires are needed ie more copper in the wires, and this also results in more house fires.
It turns out about the same number of people die, ie house fires versus electrocution.

50/60Hz is primarily historical.
These days with VFDs you can have whatever frequency you like.

What's more whacky is the choice of 220-230-240-250V but for most purposes it doesn't matter. as most appliances can handle this range of V anyway.

Most people think of the V arriving at their shed as being something constant but it's rarely that. All its meant to be is a supply of power which the appliance eg computer, regulates to its specification.

The scientific definitions of voltage and current are interesting

Ampere is now a fundamental or "base unit" in science and tech
The base unit used to be Charge (Q, in Coulombs) based on the charge on an electron.
Current (amps) was then was "so many charges per unit time".
In 2019 current became the base unit because it could be defined in terms of of a force between two wires carrying currents ie mass/length/time.
Form Wikipedia
"The ampere is that constant current which, if maintained in two straight parallel conductors of infinite length, of negligible circular cross-section, and placed one metre apart in vacuum, would produce between these conductors a force equal to 2×10−7 newtons per metre of length."

Volts are defined in terms of kg/m/s and elementary charge "e"

Here is a very informative diagram from Wikipedia showing how all 6 of the base units are related.

The base units are the 7 shown in the inner circle
s , seconds for time
kg, kilograms for mass
mol. mole for amount of sunstance
cd, candela for luminous intensity
K, kelvin, for thermodynaic temperature
A, ampere, for current
m, meter for length

The outer ring (except V which I have added) are the fundamental constants used to define the base units, eg the meter is defined in terms of the speed of light "c", the ampere is defined in terms of fundamental charge (e)

I have added voltage so you can see where it comes from - it is derived from three base units (m, s, kg) and a fundamental constant "e" which is elementary charge
This was only worked out in 2019.
From about 2000 to 2013 I was in the thick of the redefinition of the "mole" but I've forgotten most of what happened because it was largely about chemists arguing with physicists over gnats whisker - being a physicist I was on their side, and all I remember is we won! :D
The wWikipedia article also has the pre 2019 version of the this diagram
Attachment 508774

Yep, electrical systems were often patented, and so like trains, every system did something a little different to skirt the competing patents. Also, the people doing the systems were competitors, so damn that fellow, I'll make sure my stuff won't work on his grid... and so forth. Sort of like trying to fit Toyota rims on a Nissan...

In the US, 220 v is 2 phase 110... Even more confusing is that 230v in the US is 3-phase 110... Then go over to Europe and it seems like every single country does something different to spite all the others.

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Originally Posted by Beardy

The Endeavour Energy representative said they were trialling some stabilising devices to alleviate the higher voltage problem but it is happening everywhere.

@truckjohn as you pointed out the systems have protection built in so as to not oversupply the system but the flip side of that is that when this happens you are not sell your power back to the grid.

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Yeah, well, that's just part of the "cost" of a cheaper system. Grid tie systems also automatically turn off if the electrical supply to your place shuts off - such as a downed line or a cyclone... So you may well be able to supply 100% of your own power, but you're still sitting there, sweating in the dark.

If you want to give the finger to the power utility and pocket all your "savings," get a battery system and set it up to only connect to the grid if your consumption exceeds your reserves. The trouble is that those cost like 3x more than a grid-tie system.

There's no free lunch... Either you pay, or I pay... I'm not surprised to learn that The Government always sides with itself when it comes down to shutting themselves down or shutting me down.

I could tell you all sorts of stories about municipal water utilities being forced to raise rates after successful water consumption reduction initiatives went through. I mean, you still have to pay for the water plant, ten-thousand miles of pipe, and it's employees, even if it's now operating at 2/3 capacity. Lots of fixed costs...

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Originally Posted by truckjohn

Yeah, well, that's just part of the "cost" of a cheaper system. Grid tie systems also automatically turn off if the electrical supply to your place shuts off - such as a downed line or a cyclone... So you may well be able to supply 100% of your own power, but you're still sitting there, sweating in the dark.

If you want to give the finger to the power utility and pocket all your "savings," get a battery system and set it up to only connect to the grid if your consumption exceeds your reserves. The trouble is that those cost like 3x more than a grid-tie system.

There's no free lunch... Either you pay, or I pay... I'm not surprised to learn that The Government always sides with itself when it comes down to shutting themselves down or shutting me down.

I could tell you all sorts of stories about municipal water utilities being forced to raise rates after successful water consumption reduction initiatives went through. I mean, you still have to pay for the water plant, ten-thousand miles of pipe, and it's employees, even if it's now operating at 2/3 capacity. Lots of fixed costs...

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Yes I get it and understand the situation but the broader community seem to think it is their right to be able to sell the power they generate back to the grid and that it should be a financially viable venture for them :?
The general talk about domestic solar is that they are doing it for the environment but the focus of the discussions always seem to oscillate around cost and saving money which highlights the underlying reason.
My motivation to install a system was purely financially motivated. I am all for saving the environment but think this is largely a placebo effect item and there are many more effective changes we can make to our lifestyle to make a difference but that is heading OT.

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Originally Posted by truckjohn

c In the US, 220 v is 2 phase 110... Even more confusing is that 230v in the US is 3-phase 110... Then go over to Europe and it seems like every single country does something different to spite all the others.

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Nope, their grids and electrical standards are standardised, so except for Romania (220V) and Gibraltar (240V) all other European countries (including the UK) are 230V. Even Russia is 230V. But it doesn't matter whether its 220 - 240V all domestic appliance should work within this range. One of my cousins owns a custom electric motor factory in Italy. His motors have work across the EU. and His 3P motors work just about anywhere.

Here in Western Australian we are supposed to be 240V but I often see voltages as high 250V and as low as 230V on my machine V/I meters. About 10 years ago we had a dishwasher on which the mother board went wonky and would not work when the voltage dropped below 240V! It was probably a faulty V reg on the motherboard but as the whole motherboard was potted in epoxy I could not get at the reg to replace it and replacing the motherboard was going to be too expensive. For about 12 months I ran the dishwasher from a Variable Transformer (Variac) set at about 105%. Then it need and even high voltage which the Variac could have provided but I deemed it too dangerous and had to scrap
At work where we ran many delicate electronic bits of gear, in my 40 years experience we had one device (an expensive 7 digit voltmeter rated for 220V) that didn't like more than 240V and had to be run from a stabilised supply.

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Originally Posted by truckjohn

I could tell you all sorts of stories about municipal water utilities being forced to raise rates after successful water consumption reduction initiatives went through. I mean, you still have to pay for the water plant, ten-thousand miles of pipe, and it's employees, even if it's now operating at 2/3 capacity. Lots of fixed costs...

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This is EXACTLY what happened here in Canberra. EXACTLY.

We had a terrible drought. The dam was empty and the local emergency supply river (Murrumbidgee) was far too low. It is fed by the yearly snowfields which are diminishing.

The local supplier (ACTEW) ran a concerted campaign that appealed to everyone to cut back everywhere. An cut they did. By SO MUCH that the pipes, sewers and drains needed regular flushing as the volumes were too low to move the ..... wastes ...

Big Problem. They ended up using their OWN water to flush the systems. Guess who paid? Hmmmm.... :~

Next problem is there was a basic usage charge.. cents per megalitre.. That fell over. Revenues collapsed, so they introduced rammed through a base rate plus "new" usage fee that Surprise-Surprise was the same as the previously charged before-reduction cost. Bills were now the same as before! GOSH!

But with now less usage.

We were vastly unimpressed.

The drought broke, the ACTEW build a stupendous new dam (its mighty, but at users cost) and it is now overflowing regularly.

Water prices remain just as high - no alleviation either on price or volume.

Bloody Government. Every. Damned. Time.

A big number was hit.

Humans have installed 1 terawatt of solar capacity, generated over 1 petawatt of solar electricity in 2021 – pv magazine USA

Apologies for thread drift...

BobL, thanks for that diagram. Back in the early '60s I bought a set of log tables (remember them) which had, inside the covers, the definitions of many physical quantities in terms of other, basic, physical quantities. I referred to them so often that eventually I learned them, and even, sometimes, understood. However, when I had to use seven digit logs, I somehow lost those tables.
Doesn't matter now, i guess, if so many of them have been re-defined.

OK, you may now resume normal service.

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Originally Posted by AlexS

Apologies for thread drift...

BobL, thanks for that diagram. Back in the early '60s I bought a set of log tables (remember them) which had, inside the covers, the definitions of many physical quantities in terms of other, basic, physical quantities. I referred to them so often that eventually I learned them, and even, sometimes, understood. However, when I had to use seven digit logs, I somehow lost those tables.
Doesn't matter now, i guess, if so many of them have been re-defined.

OK, you may now resume normal service.

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Yep - log tables I remember well, used them mainly in high school along with slide rules which I used all through uni undergraduate. Only in my last year of uni were we allowed to used calculators in one final exam - statistics, and as I couldn't afford one I had to borrow one from a mate. My first year out teaching I bought my first calculator and a couple of Years later I bought a programmable HP41CV which I worked hard especially when I went back to uni to do postgrad stuff. I still have the calculator and it still works but I also have a 41C simulator App on my phone which I use almost daily.

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Originally Posted by BobL

Yep - log tables I remember well, used them mainly in high school along with slide rules which I used all through uni undergraduate. Only in my last year of uni were we allowed to used calculators in one final exam - statistics, and as I couldn't afford one I had to borrow one from a mate. My first year out teaching I bought my first calculator and a couple of Years later I bought a programmable HP41CV which I worked hard especially when I went back to uni to do postgrad stuff. I still have the calculator and it still works but I also have a 41C simulator App on my phone which I use almost daily.

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HP41CV was an excellent calculator + peripherals. I once wrote a program for a HP9845 + plotter so you could type a HP41CV program in and produce the program in bar code, which could then be read by the 41CV+wand whenever you wanted to use it. Also loved the RPN notation.

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Originally Posted by AlexS

HP41CV was an excellent calculator + peripherals. I once wrote a program for a HP9845 + plotter so you could type a HP41CV program in and produce the program in bar code, which could then be read by the 41CV+wand whenever you wanted to use it. Also loved the RPN notation.

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We had a 9845 in our lab - I loved using it.

At one stage I wrote a crude numerical model for a nuclear reactor for the 41CV. The memory was so limited the program had to be organised so parts of the program and intermediate data were held on about 10 magnetic cards and swapped in and out as required. It did this eight times over about 16 hours to get a final basic result. This came down drastically when I got my first PC and then down to about 3 seconds when I got a 386 with a maths coprocessor.

Of course then I expanded the model and had it running for about 20 minutes and then out to even an hour and was able to run multiple models at the same time. I still have the program cards and mag reader for the 41CV - haven't used them for about 30 years.

RPN - is indeed a winner.

I still use my trusty HP32S RPN Scientific which got me through uni some 35 years ago.

Attachment 508904

We poor students could only lust after HP41C/CV, but thanks to the wonders of technology I now also use a 41C app on mobile phone.

Having grown up with RPN, it's very difficult to use anything else !

BobL, its some of your VFDs, but REALLY BIG!

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