Earlier this year in Western Australia, a rule went into effect that all new or altered electricity network connections must have a circuit breaker as the main switch. In some cases, this circuit breaker will trip if you use more than a piddly 20 Amps in your home.
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UPDATE April 6, 2023: The WA Government has announced the mains switch circuit breaker rule has been revised – and there’s good news. Find out what’s happening here.
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This is not retrospective. Existing homes must only comply with the new rules if they undergo an electrical alteration such as installing solar, batteries or an electric car charger1.
Why Does This Rule Matter?
Replacing the main switch with a circuit breaker results in the enforcement of maximum demand limits for an electrical installation.
In other words, you need to watch how much power (i.e. Amps) you use at any one time, otherwise the main switch may trip, leaving your house without power until you switch stuff off and reset the breaker.
Metropolitan Vs Regional Vs Rural
The network service capacity in the Perth metro and major regional areas is different from our cousins in rural Western Australia. Unfortunately, as usual, the country cousins get the worst deal.
The following are network service capacities for Western Power and Horizon Power customers in WA, and therefore the mandated main switch circuit breaker sizes.
For those of you struggling to view the chart on your phone, that’s:
- Metro and major regional – 63A single phase, 32A 3-phase.
- Rural – 32A single phase, 32A 3-phase, 16A split-phase (now changed to 20A).
Is This Really A Problem?
Not for me. I’ve got 63 Amps and no electric car! But it could be a problem if you want to fast charge an EV, if you want your home battery to be part of a VPP, or for any household limited to a maximum of 32 Amps per phase at any one time. That’s not a lot of Amps to play with in the 21st century.
Hubby will be in deep shit if he tries to strike up the arc welder in the back shed and trips the main switch while wifey’s cooking the Sunday roast chicken in the oven2.
Even if your loads are balanced across 3 phases, you’ll have to be careful when using high-powered appliances such as air conditioners, water heaters and ovens.
I’d go as far as saying it’s going to make life more than uncomfortable for rural households on single phase running their air conditioners on a hot summer day while simultaneously trying to get on with their life.
People may even avoid installing solar panels, batteries, air conditioners, induction hobs, electric hot water or car chargers to avoid triggering the requirement on their homes.
Let’s Talk About Solar
Let me be clear. Your solar power system will never overload and trip your new main switch/circuit breaker. In fact, your solar power system will help to reduce your maximum demand by taking the strain off the grid during the daytime. Yay for solar energy!
You: “What about exporting my power?”
Me: “Same thing. Exporting power will not trip your main switch/ circuit breaker by overloading it.”
The largest inverter sizes allowable in Western Australia will only ever export at a maximum rate of about 21A per phase. This will be even less when you’re using power during the day. Yay again for solar!
But…
Clause 4.5.3 in Basic Embedded Generator (EG) Connection Technical Requirements tells us you might need an extra pole in your new main switch/circuit breaker if a Western Power AMI meter is used for DER (distributed energy resources) management purposes.
This will be connected to the auxiliary function terminal of an AMI meter. The auxiliary function terminal may be used for either direct or indirect control of your inverter.
Yes, big brother will have the ability to turn on and off your solar power system – but don’t worry. It’s hopefully almost never going to happen as Finn clearly explains here.
You: “What about when the sun goes down? Won’t I have to watch my usage more carefully or risk my power going out?”
Me: “Oh shit, I forgot about that. Um, would you like to buy a battery?”
Batteries – The Good And The Bad
Like solar inverters, home battery systems also have size limitations. Electricity network rules in Western Australia ensure that your battery will only ever charge and/or discharge at a maximum rate of about 21 Amps per phase.
Me: “In addition to size limitations, there are also time-of-operation limitation rules.”
You: “You’re f*ing kidding me.”
Nope. Western Power have that covered. See clause 4.3.3 in Basic Embedded Generator (EG) Connection Technical Requirements. The following is mandatory:
10am to 3pm – no discharging.
6pm to 9pm – no charging from the grid.
Good news. The above times are already configured into the battery setup by your installer so you don’t have to worry. But here’s where it gets tricky. The following is recommended but not mandatory:
6am to 10am – avoid charging if battery level is greater than 50%
3pm to 9pm – may discharge for net-load reduction.
9pm to 6am – may charge or discharge as required.
If your battery is configured to charge from the grid, you’ll have to watch your power usage at that time, otherwise you may trip your main switch/ circuit breaker. If your battery is charging at 21 Amps, that only gives a rural WA home 12 Amps (2.8 kW) to play with. A kettle and toaster together will pull more than that.
You: “So I’m damned if I do, damned if I don’t?”
Me: “Not necessarily. You are only likely to be on a 32 Amp breaker with 3-phase power, otherwise you’ll have a generous 63 Amps to play with. Although rural folks only get 32A on single phase.”
If you’re a 3-phase customer and you’re nice to your installer, he will lovingly and professionally balance your loads across all 3 phases and have a nice conversation with you about energy management. This would include configuring your battery to best suit your particular situation.
This battery stuff I told you about above will probably never be an issue… unless… you’re a country cousin living on a rural property with a 32A single phase or 20A split-phase supply. My heart goes out to you brothers and sisters, you are well and truly screwed. A kettle, toaster and bar heater all on at the same time will bring you to the edge of tripping that 32A breaker.
A Quick Word About EV Chargers
If you’re lucky or rich enough to own an electric car, then read on. If you’re wondering when to make the EV move, you better jump in for the ride too.
With regard to this discussion about the ramifications of the new main switch/circuit breaker rules in Western Australia, it’s best to think of your EV as a battery on wheels. When you plug it in at home, it’s subject to the same rules as a home battery.
Most dedicated single-phase and 3-phase home EV chargers are rated at 32 Amps per phase.
You: “32 Amps, ouch. That’s a pretty fine line as far as my main switch/circuit breaker is concerned. Won’t it trip straight way?”
Me: “No way. The clever people that make EV chargers thought of that. Read on.”
There are smart chargers on the market that can charge at different rates. You can also schedule charging for off-peak times, and in some cases, the charger will automatically switch off other large household loads for you when you’re charging.
For more on this subject, I thoroughly recommend you read Finn’s EV Charging 101 Guide.
Fortunately, Synergy (WA electricity retailer) is using the carrot approach rather than the big stick to tempt you away from peak usage times, and now offers a reduced tariff for off-peak electricity called Midday Saver. Do your sums.
EV charging during off-peak times may save you dollars and go a long way to prevent accidental tripping of your now despised main switch/circuit breaker by reducing the chance other appliances are running while you charge your EV.
Under current rules, you need permission from Western Power to discharge an EV battery into the grid (V2G). You can apply here.
What Is The Rationale Behind This Main Switch Ruling?
This is Western Power’s official word – New Requirements for WA.
This is mine…
Electricity networks across the world have a colossal job in front of them trying to knock their respective grids into shape to accommodate an evolving decarbonised energy profile.
It’s not as easy as “let’s just put on lots of solar panels and drive around in electric cars”. There are very real engineering and technological challenges to work through, thankfully by people smarter than me.
My guess is that the main switch/circuit breaker ruling is a tool (a very blunt one) to help Western Power manage aspects of the energy profile and power quality by addressing load creep, phase imbalance and flattening the load profile curve.
They are very aware of the imminent wave of power-hungry electric vehicles coming to our shores and want to be prepared.
Unintended Consequences
I’ve already told you our rural neighbours have to make do with a measly 32A single phase or 20A split-phase supply while living in a modern electrified world. This is totally unworkable and really needs to be addressed.
The other thing that irks me is that although this ruling is for all new and altered connections, it mostly affects people installing solar, batteries and EV chargers. These are the very people driving the much-needed energy revolution. They should be rewarded, not penalized!
Double standards? Should this be rolled out across the state for all Western Power customers? Are solar power and battery owners somehow classed as high-energy users above others?
The last thing we want is for people to turn away from solar power, batteries and electric vehicles simply because of an ill-conceived regulation.
On the other hand, is this a good measure to keep everyone’s energy usage in step to help an evolving electricity network?
Me: (in a pirate voice) “Arrr, circuit breakers for everybody or none at all I say! Arrr you with us or against us?”
You: “Reply in the comments section below with or without pirate voice.”
Additional notes
After this article was written, a Western Power spokesperson reached out with the following response to my earlier communication:
“Western Power is aware of concerns raised by the electrical industry on the adequacy of the standard regional and rural supply allocation as customer energy needs change. In response, it is reviewing and assessing the opportunities, risks, and consequences of alternative options, and will provide an update to stakeholders by the end of the year.”
Footnotes
- You can get the rule straight from the horse’s mouth by reading the Western Australian Service and Installation Requirements (clause 11.1.2 and 11.6.4.3) and Basic Embedded Generator (EG) Connection Technical Requirements (clause 4.5.3). I wouldn’t recommend reading the whole thing though, because you won’t get through in one sitting. To be honest, many Western Australians working in the industry have not even read these. ↩
- or vice-versa ↩
About Kim Wainwright
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1) My daughter in South West WA has just moved into her first new home, as a good father I promised to buy her a solar system, if she went gasless in her choice of appliances, hot water etc. Should I wait until this debacle has been sorted?
2) Moving further south next year to Molloy Island, had Plico install a 8.8Kw solar plus 10Kw battery system last month, a Western Power went to change the old meter over yesterday, but couldn’t because it has a single neutral connection, is this part of the changes by Western Power?
Hi Robert,
If you install a solar power system or battery, your daughter’s property will almost certainly have to have a 32 amp circuit breaker as the main switch.
If she has a 100% electric household as you suggested, she will CERTAINLY experience REGULAR power outages just trying to live a normal life.
The bigger problem is that you can avoid installing solar or batteries, despite the damage this is doing right now to our industry, but if you add ANY electrical loads like an oven or airconditioner, technically you will still have to fit the current limiting circuit breaker. Sorry.
Consider the following loads, then think about whether you can realistically stay under 32 amps:
Electric Oven = 16 amps
Electric Induction Stove = 50 amps
Electric Hot Water Service = 16 amps
Reverse Cycle Airconditioner = 10 amps to 25 amps
Toaster = 10 amps
Microwave = 8 amps
Portable heater = 10 amps
Kettle = 10 amps
washing machine = 10 amps
dishwasher = 10 amps
dryer = 10 amps
vacuum cleaner = 8 amps
water pump = 4 amps
hair dryer = 7 amps
Air conditioner and stove = POWER OUTAGE
microwave, hot water, oven and kettle = POWER OUTAGE
Oven, dishwasher and dryer = POWER OUTAGE
Okay.
Forget all of that, for the moment – I am not putting it down, just making a single, simple point, that I think, makes all of those figures, redundant.
“Single phase rural – 32A”
Can anyone find a freestanding electrical stove, that is less than 32A?
The only one that I found, that is 32A, is a 50cm wide stove.
All of the 60cm and larger stoves, START AT 40A!
What drugs were the writers of the regulations, tripping on?
Primary objective of state government? Cause harm to WA.
WA state government = Public Enemy Number One (the PENO people).
We live South West 70km from Collie
Just got a quote for solar and found we would need to switch our 80AMP fuse for a 32 AMP fuse to accommodate solar.
This makes solar untenable to us.
If you pay $100,000 you can switch to a 50AMP fuse.
Yet recently WA government was required to inject money into Collie Coal mine.
Disgusting!!!!!!!!
“Euromaid EW50 WHITE” – “Direct Wired:32 amps hardwired”
“Westinghouse WLE532WC 54cm white electric freestanding cooker with separate electric grill, fan forced electric oven, 60 minute timer and a 4 zone solid cooktop.” – “Connected load KW9.1” – 38A
“Haier 54cm Freestanding Range
HOR54S5CW1” – “Plug type Hardwired – 40 amp”
“BFC60EMW1 60 cm White Solid Hotplate Upright Cooker” – “Fuse:min. 40A”
“Turn off the lights and everything else electrical! It is time to cook dinner, here in the Dark Ages Western Australia.”
Thanks Andrew, good info…told my daughter about this issue, so waiting with my purchase at the moment (Sorry about your business), until Western Power maybe reverses their silly decision, see what they come back with at the end of the year…but I’ll bet when on of the premier’s mates moves south and their fancy homes Power trips out, that something will be done ???
I bought this Northam WA property 23 months ago: 4/2 house + 2/1 granny flat + 60kL pool + 95m2 shed + 2kW solar: single ph 63A?
In May I had installed RC aircon to flat, heat pump to pool(13.8A running) and upgraded to 3ph from run-in right through to shed new 3ph 80A main sw,
25Aug had old solar replaced with 6k6W PVA (2k2E + 4k4W) into 3ph 5kW hybrid inverter: now have 2off shiny new 32A breaker as main sw!
One in Meter box on boundary pole and other in SB on house wall. The installers also put a “secret” directional meter/counter behind the supply side panel in SB. I have not installed my lathe or welder in shed but it is cable limited to 15A/ph … methinks a battery might be needed sooner rather than later. Will start complaining on first tripout.The new WASIR off 311 pages sure makes for interesting reading.
Hi Bob, thanks for your info…where do I access the Western Power info you mentioned…The Company (Plico) that provided my system on Molloy Island, never mentioned the 32A issue, although the installer did replace the main switch as part the job, the previous switch was pretty old, but he just put in a normal switch (I think), didn’t look at the amps either..going down this weekend to have a look…a bit annoyed at this time…
Hi Bob,
If you’ve got 3 phase, you’re one of the lucky ones: you may be able to “rebalance” your loads across the phases.
Getting 3 phase was a smart decision: unfortunately not everyone can afford the upgrade, and most rural properties don’t have the option.
Hi Robert,
I followed the links in the main article ” Basic Embedded Generator (EG) Connection Technical Requirements. ” and this one “New Requirements for WA.” but here is the direct URL: https://www.westernpower.com.au/media/5095/western-australian-service-and-installation-requirements-20210729.pdf
As for the 3ph, I could see that it was available in the street and got an estimate o $10k to upgrade when negotiating the purchase as I brought a lathe and grinder with me so wanted the option in the shed at least… anyway when it came to installing the heatpump on the pool the sparky worked out he needed to supersize the run-in from the meter pole to the house, then to the pool, and get Western Power to upgrade their end to 80A, so I asked about what $ difference or 3ph instead and that actually worked out cheaper even with adding the extra run to the shed because standard cable sizes were adequate – so the decision was a no brainer.
We live South West 70km from Collie
Just got a quote for solar and found we would need to switch our 80AMP fuse for a 32 AMP fuse to accommodate solar.
This makes solar untenable to us.
If you pay $100,000 you can switch to a 50AMP fuse.
Yet recently WA government was required to inject money into Collie Coal mine.
Disgusting!!!!!!!!
Julieanne, I feel your pain. There’s an update here that says Western Power has started a trial in parts of the South-West and Wheatbelt where the supply available to premises will be equal to that of metropolitan areas.
Info here… https://memberarea.necawa.asn.au/Admin/ViewContentPage?uniqueName=update-on-western-powers-main-switch-requirement-rural-trial
or directly from the horses mouth here… https://www.westernpower.com.au/community/news-opinion/rural-power-supply-allocation-increase-trial/
I’d be quizzing Western Power about this and keeping a close eye on where it goes if I were you. It might take a while to play out. Good luck.
Hello again Juilianne. I think you’ll be happy to hear some good news on this. It looks like you’ll be able to get rooftop solar after all. The installer will still have to change the main switch to a circuit breaker as per rules governing all WA, however they’ve upped the limits on single-phase rural in line with metro. That’s 63A single-phase, 32A 3-phase, 32A split-phase. I’d get back in touch with the company that quoted you before the powers that be change it back again! https://www.solarquotes.com.au/blog/wa-circuit-breaker-mb2889/
That rural limit (16 A/phase for a 480 volt (240 + 240) )system, probably a swer line, is astonishing. We have a rural property on a swer line, our pole fuse is 100Amp on a 240 volt wired transformer. Meter panel main fuse is 80 amp. We did fit an 80 amp circuit breaker for our main switch and have tripped it on several occasions during social functions.
Sounds like you have great parties!
You have got to be kidding. An 80 Amp circuit breaker will not trip until until nearly 120 Amps. A kettle takes 8 Amps. A hot water system usually takes 10Amps. A microwave and toaster may take 4 Amps. What on earth were you running?
Heinemann 80 amp CF series Standard curve (Curve 2): 100 amps will trip the CB between 10 and 40 seconds: Our main loads are electric heaters around the site, running close to the 80 amps. Sometime someone turns on a hot water element or electric stove at 15 amps and more resulting in a trip shortly after. No data log sorry (but being considered). The CB was new when installed but I calibrated it anyway to be sure of its compliance. Too much to loose if it’s a dud!
Peter Brett,
Data for Heinemann Series CD-CE-CF Compact E-frame circuit breakers can be found at: https://www.eaton.com/content/dam/eaton/products/electrical-circuit-protection/hydraulic-magnetic-circuit-breakers/heinemann-series-cd-cd-cf-compact-e-frame-circuit-breakers.pdf
Time delay curves (at 25 °C ambient temperature) are shown on page 6 for 50/60 Hz AC:
125% overload Curve 1 trip delay variation from 100 to 830 seconds
125% overload Curve 2 trip delay from 13 to 90 seconds
125% overload Curve 3 trip delay from 0.8 to 6.4 seconds
Trip time delay will decrease as ambient temperature is raised higher (above 25 °C) and increase as ambient is lowered.
Hm-mm, I am of the understanding that here in WA you can only have a 5kW inverter – if you wish to receive a FiT – single or 3 phase.
That is, 21A on a single phase, or an average of 7A per phase, on 3 phase (good for less voltage rise, not so good if any one phase goes excessively high shutting down the inverter – an early problem we had, that was fixed by Western Power).
Our 3-phase inverter runs from 6.24kW of panel rating – but only clips to 5kW a couple of hours around midday over summer. Trouble free for approaching 6 years (touch wood) – we are finally ‘in the black’.
Interestingly, our incoming power is protected by fuses rated at 100A per fuse!. This will be good if long-range EV prices ever come down to less than drug-money levels!
Sorry to cherry pick from your overall point, but does the 5kW limit really only apply if you want the FiT? If I wanted to vastly overbuilt solar for some future purpose I could get more than the 6.6 standard as long as I kept all the power?
Hi Jake
I’ll have to re-check – as best I recall you CAN have a domestic 15kW 3-phase inverter on the grid, but with no FiT – with 20 kW of panel rating (1.33333 × 15).
Corporates (e.g. shopping centres, gymnasiums) can go higher, but no FiT.
I found this on a Synergy or Western Power some years ago – but it is possible the details have changed in the interim. I’ll see if I can find the link and get back to you.
Of course, you could follow Lawrence’s suggestion, and have a second system off-grid?
Hi Jake
Recent website data suggests I was correct – Western Power allow a residential maximum inverter size of 5kW on single phase. This qualifies for FiT. Subject to their approval, they may let you have 15kW on 3-phases – but then you forgo FiT.
If you are thinking of a new, or upgraded system, you may become the subject of this whole post – with breaker-limited import capacity. There has also been talk of remote switching of exports.
Wish you luck.
Hello.
Go to
https://www.westernpower.com.au/media/5870/basic-eg-generator-technical-requirements-20211202.pdf
download and view the PDF document.
Page 15, Table 4.1 (not sure how this will display, due to formatting):
”
Table 4.1:
Maximum System Capacities for Large network category
Connection Basic
EG
service
system
phase
Maximum basic EG system capacity
Single DC coupled
energy with BESS(1)
source
Export limit(3)
(4)
AC coupled with BESS(2)
(i.e. no BESS)
Single-
phaseSingle- 5 kVA
phase5 kVA5 kVA PV (or other energy
source IES) and 5 kVA BESS IES
5 kW
Three-
phaseSingle- 3 kVA
phase5 kVA3 kVA PV (or other energy
source IES) and 5 kVA BESS IES
5 kW
Three-
phaseThree- 15 kVA
phase15 kVA15 kVA PV (or other energy
1.5 kW
source IES) and 15 kVA BESS IES Except where
(up to 5 kVA per phase)
PV (or other
energy source
IES) capacity
≤ 5kVA then
5 kW export
limit
“
Sorry Jake – forgot the link..
https://www.infiniteenergy.com.au/maximum-residential-solar-pv-system-size-wa/#:~:text=Eligibility%20for%20DEBS&text=Assuming%20Western%20Power%20gives%20you,inverter%20above%205kW%20in%20size.
We experienced this problem in May when ordered to replace wooden pole ?meter box ,
the contractor tried his up most to speak to and put our case forward .
He was stonewalled by some power person in Perth who had no idea about rural properties running welders , wool presses air compressors and a homestead .
The power persons take was upgrade your transformer, which is 10 kva and working fine to 25 kva at our cost .
All our neighbors have had similar expriences .
Frustrated by this stupidity
Brian ,great southern farmer.!!!!!!!
Here in Rural NSW I am on a 2 phase 480v supply. The 5 farmlets are on a 25Kw transformer. I used to overvoltage trip my inverters consistently, until the control was changed to voltage control. Now we all have better Solar PV voltage regulation because I wind back when the voltage goes high. I think I actually export more now because my inverters run all the time. (about a 2 min cycle if the inverter trips).
I have 12Kw of Zenaji batteries, that get out house through the morning & evening peaks. (I recharge to 30% at 1am for the breakfast rush!) The battery is usually full by 10am.
My electric cars are charged by 10a circuits atm. I will be installing a 32A EVSE very soon. btw, EV charger efficiency drops markedly at less than 10A, so the 10A charger should be the slowest you use (at abt 15Km/Hr charge at 10A)
One thing that can be done in WA Rural is to run a virtual off-grid setup.
Design the system to run mostly off the Solar PV + Batteries & really
try to only use the grid as a virtual generator. There is a Dairy farmer doing just that, that was on the Rural show on Rural ABC radio recently. Dairy farmers must reliably run the refrigeration for the milk. In some cases this uses most of the available power.
In my best pirate voice this seems to signal the approach of the death spiral for the power companies given the rising connection charges as well as restrictive regulations at least as far as early adopters are concerned. If you have a property with spare roof space operating two parallel off grid systems would now seem interesting.
We have a mostly electric home with gas space heating and were looking at moving to all electric this now seems less attractive especially as gas prices are now on offer with a 50% discount in WA.
I have friends in the US who have no electric power connection and large solar systems and use gas to power back up generators maybe this is food for thought. This avoids the electric power connection fee and one is then free to have a solar system of choice.
Kim Wainwright,
“My guess is that the main switch/circuit breaker ruling is a tool (a very blunt one) to help Western Power manage aspects of the energy profile and power quality by addressing load creep, phase imbalance and flattening the load profile curve.”
I’d suggest Australia needs to become much more energy efficient, and homes need to be a contributor to that process.
Per an Energy Source & Distribution article headlined It’ll be impossible to replace fossil fuels with renewables by 2050, unless we cut our energy consumption, dated Aug 25, began with:
https://esdnews.com.au/itll-be-impossible-to-replace-fossil-fuels-with-renewables-by-2050-unless-we-cut-our-energy-consumption/
I certainly agree that we all have a responsibility to be as efficient in the use of our resources as possible, this is a nonsensical approach to that particular issue. Most people live in metropolitan areas, so would it not make more sense to limit the main breaker rating in metropolitan areas?
Matt Cass,
“Most people live in metropolitan areas, so would it not make more sense to limit the main breaker rating in metropolitan areas?”
I suspect the standard connection 32 A (single phase) & 16 A (multi phase) restriction for WA rural areas has something to do with the available local electricity distribution infrastructure – wires & transformers. The population density (and long supply cable distances) in rural areas probably doesn’t justify an economic business case for the local network provider to increase the electrical current carrying capacity, unless the user wants to pay for a non-standard upgrade.
These changes are being driven by grid limitations and energy management problems hence they are directed where the greatest perceived problems are.
Fitting more breakers in the metropolitan area will do nothing to address problems in the rural grid. I am not apologizing for the abysmal performance of Western Power who seem totally reactive rather than moving to address emerging issues. Sure there are a few pilot and other small projects to address problem areas for instance pumped storage at Walpole.
A more positive approach would be to require people who install PV panels to install correspondingly sized battery storage systems. This would address the daytime peak output problems as well as the evening demand peak just as the sun goes down.
We all have the right to harvest the free energy from the sun however if there are gross oversupply issues during lower demand periods storage is the only answer. If we want to harvest free energy and we cannot manage any surplus ourselves it seems that the grid should be able to charge for that service to us?
Until we see grid scale storage in WA by whatever means the issue remains how does the grid deal with significant PV production in times of low demand? No amount of hand wringing and gnashing of teeth will alter this.
Sure it is an issue for Western Power to address and they are very slow to act so just get your storage and PV on location configured in an off grid setup and then use the grid only to “charge” your batteries as required.
Sure there will be no feed in tariff which is close to nothing in any case but you will be able to provide almost all your power requirements and not be subject to any of the current round of regulations.
Rural customers with a little bit of extra land than their city cousins, are in a great position to install a second Solar PV + Battery Storage Off Grid Solution on their property in addition to an already existing On Grid System.
Importantly the second Off Grid Solution is entitled to STC’s and the System size can be quite large. The CER rule is that the second system plus the first system must in total be no greater than 100 kW. So if you have a 10 kW On Grid System you could install a 90 kW Off Grid Solution for a total of 100 kW of Solar PV Systems and receive the full quota of STC,s applicable to the location, for that 90 kW Off Grid Solution.
The optimum systems inter-operability functionality, including load circuits switching and control between the Grid Supply Source and the Off Grid Supply Source, will require the services of an Off Grid Solutions Integrator specialist experienced in these designs.
Lawrence Coomber
Why is anyone surprised?
The voters of WA elected a government tjhat is owned by the fossil fuel companies..
The state government wants to fprce all households to return to using stoves, heating, and water heating, that burn organic matter, be it wood, coal, or gas.
Unfortunately this seems to be true.
Ironically, the same government are disconnecting the gas mains to houses in the Esperance area, and the government are paying for full electrification of the affected houses……
……. and I guarantee you they won’t be stuck with a 32 amp supply. They’ll get a 63 amp supply. otherwise they will trip their current limiting breaker every time they turn on the oven and stove together.
Well, aren’t i lucky….
horizon power is much better ?
I wouldn’t say that. In Esperance they are not even allowing you to instal solar connected to the grid ATM.
Go totally off grid not partially on.
Too complex otherwise.
Too dependant accomodating all the different needs of all of society
As many as possible Total independent households needed rather than this evolving hybrid system.
Do you go for a drive without food water tow rope tools spare tyre, blankets, mobile phone or rely on a tap , a tow truck or travtor if you are bogged , the RAC to change your flat tyre , a t shirt to keep you warm and smoke signals to get assistance…providing you brought some matvhes and they were kept dry.
Now, here’s something to consider.
In the document published at
https://www.westernpower.com.au/media/5870/basic-eg-generator-technical-requirements-20211202.pdf
on page 15, in Table 4.1, is
”
Connection service – Single phase
Basic EG system phase -Single phase
Maximum basic EG system capacity
Single energy source (i.e. no BESS) – 5 kVA
DC coupled with BESS(1) – 5 kVA
AC coupled with BESS(2) – 5 kVA PV (or other energy source IES) and 5 kVA BESS IES
Export limit(3) (4) – 5 kW
…
Connection service – Three phase
Basic EG system phase -Three phase
Maximum basic EG system capacity
Single energy source (i.e. no BESS) – 15 kVA
DC coupled with BESS(1) – 15 kVA
AC coupled with BESS(2) – 15 kVA PV (or other energy source IES) and 15 kVA BESS IES (up to 5 kVA per phase)
Export limit(3) (4) – 1.5 kW Except where PV (or other energy source IES) capacity ≤ 5kVA then 5 kW export limit
“.
Now, as mentioned above, in the SWIS grid, the standard single phase “mandated main switch circuit breaker size”, as is the “SEC fuse” (the fuse associated with the Western Power meter), is 63A.
For a 240V single phase supply, that is (P=VI) 15120W; close enough, to 15kW.
So, the question is this; as it would not exceed the “mandated main switch circuit breaker size”, or, the “SEC fuse” (the fuse associated with the Western Power meter), why are single phase households not allowed the same limits as specified for the three phase customers; 15kW for grid tied inverter, or, 15kW for hybrid inverter with DC coupled BESS, or, 15kW inverter with 15kW ACC coupled BESS; each scenario, export limited to 1.5kW?
That would fulfil the need to minimise disruption to the decrepit and fragile grid, if that would be the genuine reason for applying the limits that we have, and, would be consistent with the circuitry of the households.
The answer is simple and twofold;
1. the limits that we single phase households have imposed upon us, are imposed for the simple reason of gratuitous bastardy, and
One negative post once mentioned a German EV owner with a fast charger, who was very heavily fined by his supplier as he was using as much as several houses and his contract definitely prohibited that.
A great opportunity to move from the Grid to Off Grid.
Domestic / Rural / Industrial /Factory Fully Functional Off Grid PV system designs are happening and will become systems of choice going forward.
Adding an Off Grid PV System to any premises is a straightforward process and can be done most cost effectively using a DC Coupled PV + Storage design and a Standalone Off Grid PV Inverter (or multiple depending on the situation.
There are several approved Standalone Off Grid PV Inverters on the CEC approved inverter list both 1 phase and 3 phase from 20 KW up to 100 KW designed to accommodate the above scenario cost effectively and reliably, and STC’s apply to 100 kW of PV.
Industrial: A common scenario often found in (daytime) commercial factory type operations, relates to the daily duty cycle requirements of specific equipment (loads) at the premises. These type of operations may even have their power requirements fully satisfied by the Standalone Off Grid PV system alone, and not require any other power source such as batteries to meet their power needs.
For managing small demand overnight loads at factories, a small DC coupled PV/Battery Storage System can be easily added to manage loads such as security lighting and any other overnight use equipment such as fridges etc.
A typical example of a larger Standalone Off Grid Specific Load Circuit would be a Golf Course that includes a large irrigation pump (or several). This scenario is perfect for adding a separate Off Grid System + VFD’s for the customer to service these specific loads only, and no batteries are required in this sort of scenario. It is easy to extrapolate this concept to any other equipment (loads) as well.
There have been virtually no commercial / industrial / domestic premises that I have come across that cannot benefit substantially by installing a Standalone Off Grid PV – Specific Loads system (with or without battery storage – depending on the premises loads).
Lawrence Coomber
Can the publishers of the blog, please publish an article that compares, for each state/territory in Australia, the restrictions applicable to
1. the grid connection fuse/circuit breaker for the mains switch, and,
2. the maximum allowed generating capacity and, if applicable, export limit, for both grid tied PV inverters and hybrid (DC coupled) inverters,
for households with single phase grid connections?
Thank you in anticipation.
Electrical Circuit Breakers are not Circuit Current Limiting Devices by design. They are Circuit Wiring Over Current Protection Devices by design.
Current Limiting is best implemented by Consumer Mains Contactors installed and managed by the Network Authority.
Lawrence Coomber
Absolutely crazy not to allow discharging between 10.00 am and 3.00 pm. One of the reasons to install a battery is to avoid having to import power when the sun goes behind a cloud as well as when it rains. It would appear that whoever makes up these rules has no real world experience.
Hi John,
This rule is in place specifically to address the growing issues caused by an excess of solar generation in the middle of the day.
WA will soon go the way of South Australia and other Eastern States: We will see a day where 100% of the daytime demand is supplied by rooftop solar.
On the Eastern Seaboard, this isn’t such an issue, because your state can just export to the nearest neighbouring state where the sun may not be shining.
In WA, there’s nowhere for that excess to go, and until we see MAJOR upgrades to the Generation, Transmission and Distribution infrastructure, the whole system becomes unstable without a moderate to large “traditional” power station supplying a sizeable chunk of the load in order to set frequency and voltage.
This rule is just one of many “knee jerk” reactions from Western Power, who are in the unenviable position of trying to play “catch up” to modernise their network, after decades of funding neglect from successive WA governments.
Western Power are still not being given the funding they urgently needed 10 years ago in order to be ready for the grid that is happening now.
Andrew,
thanks for the thought-provoking comments. Do you think reducing main CB ratings on properties is preparing for loss of base-load generation in the future? I’m interested because it could be the eastern states go down the same path, sort of forcing people to install batteries?
Hi Peter,
Western Australia is feeling the “pinch” of a rapidly changing generation mix – much sooner than the east coast or indeed most developed countries’ networks.
This is because WA is an isolated network.
I don’t think the reduction of CB ratings is preparing for loss of “base-load” generation. I think it’s a “catch-up” measure to restrict energy usage by customers so that the over – stretched and under – engineered rural networks can cope. The second reason is to manage voltage regulation which is being seriously challenged by distributed generation. The less solar power connected to the rural grid, the less challenges the network operator has. It’s in their interests to discourage the connection of solar at private premises.
The network operator (Western Power) are in an unenviable position: They need to deliver reliability and availability targets, but they are not being given enough money by the state government to do this with the changing load and generation characteristics.
They are presently left with few choices. Unfortunately the extremely blunt instrument they have chosen is to restrict supply to rural customers to an outdated (and previously never enforced) 32 amp limit, in a rather desperate attempt to manage their obligations without the $$$$ to do the job properly.
The blame lies squarely at the feet of the state government – but to be fair, the blame lies at the feet of every state government for the last 40 years. The current government and the current energy minister are just the ones who happened to be there when the final straws were applied to the proverbial camel’s back.
This DOES mean that the current government, and the current Energy Minister, are going to have to be the ones to deliver on the neccessary funding and infrastructure investment to make the WA rural network functional for all it’s users in the 21st Century. Will they do so? We’ll see.
Possibly the Eastern States may start experiencing
Hi Andrew, just a comment re Peter’s statement “should we all get batteries”, I have recently connected with Plico Hybrid system on Molloy island re being at the end of the mainline in South West WA, I now have the Redback app working and while things need settling in on my tree covered home site, I have noticed that on a few mornings the system was only recording only a 0.1 Kw (66 Watt ??) discharge into the grid, whilst all the panels were exposed to morning sun, when I rang Plico support, they could see the same, but stated that Western Power had some glitches in the system, so were able to control the outflow of solar energy?, although I wonder if the Hybrid controller switch had influence on this as well. One good thing is that I’ve a 0.1 Kw discharge into the grid at night, but against that (apart from today), the system was using grid power to recharge the battery first thing in the morning. So although I am and always will be a solar fan, I’m just wondering if the grid companies have other ideas in mind to stablelise their precious grid.
Cheers Robert (love reading these posts)
Thanks Robert Bandura for the detailed reply, it’s a very good outline of the troubles faced by the poles and wires businesses (and the transmission guys too). A friend nearby in a dead-end Court filled with solar-powered houses suffers from high voltage during summer when he’s at home during the day and everyone else in the street is at work, drawing little power. Cheers Peter B.
It would appear that WA is still in “standard operating mode”. Several lifetimes ago, when I was living there(thankfully employed by the Commonwealth) they had yet another dry spell and water became an issue. So the Govt did all the water conserving and saving stuff, which the people eagerly adopted. So their bills went down.
The WAWA (water authority) twigged that its revenue would drop and that the Govt would still want the same dividends. So by a dint of lobbying the water charges were increased.
Ah, Denis; I suggest that, instead of “WA is still in “standard operating mode””, it would be nore appropriate to say “WA is in SNAFU mode, with no hope of escaping it, without a change of government”.
The state government has apparently decided that the WA state anthem should be “We’re the Flintstones – Come and have a Yabba Dabba Poo time in WA”.
Interestingly, in the Australian feral constitution, is
“117. Rights of residents in States
A subject of the Queen, resident in any State, shall not be subject in any other State to any disability or
discrimination which would not be equally applicable to him if he were a subject of the Queen resident in such
other State.”
banning the discrimination against “subject(s) of the Queen” on the basis of where they reside (on a state basis of residency).
But, in WA, discrimination on the basis of where a person lives, is evident, in that people who live outside the Perth metropolitan area, are openly victims of discrimination, both in the changes forced on the people of WA, in the sinister and unscrupulous changes to the state constitution, to protect the state government (the PENO People) from adverse election results, by prohibiting representation in the upper house, for residents outside the Perth metropolitan area, and, the restictions on electricity provision, where people outside the Perth metropolitan area, are banned from having and using, electric stoves, and, from generally, having adequate lectricity supply.
So, yes, “WA is in SNAFU mode, with no hope of escaping it, without a change of government”.
These rules should be highlighted by the eastern states newspapers and other media. It’s a very disturbing sign of what’s ahead for them as well I suggest. Thanks for placing it on the blog.
Thanks Ronald.
One word: Wow.
We “live in interesting times” as the grid very slowly changes from a 20th century dinosaur to a modern, efficient, green network.
I’m not even remotely surprised though, as the powers that be have had their heads in the sand for FAR too long, then come out with knee jerk reactions like this. I wouldn’t call it a blunt knife- I’d call it a razor sharp machete!
As a ex both electrician AND electrical engineer, I could manage our life to cope with these restrictions with no major difficulties. I’d basically go almost completely off grid and manage our use to barely use the grid and mainly only for battery charging in inclement weather…. or maybe just disconnect completely and have a generator available. There are pros and cons with both approaches.
(For me the biggest disadvantage of a complete disconnect is wasting excess solar power rather than powering somebody else’s appliances.)
There are some great and surprisingly inexpensive DIY battery solutions available these days- but only IF you have both the required knowledge AND skills.
HOWEVER for the average consumer with very little electrical knowledge (including for example my wife), or those who can’t spend enough money to upgrade and go mostly or all off grid, this could be a massive nightmare!!
Very unfair for those of us trying to upgrade older homes with simple “luxuries” like ceiling fans, airconditioning or other modern appliances. This has just happened to us and we are only 15km out of Bunbury – certainly not Rural – but Regional it seems.
In addition, we don’t have a water supply to our area (2acre bush blocks, Leschenault) and so have to run bores and water pumps to the home, over and above normal electrical use.
We have just added some ceiling fans and airconditioning to 2 bedrooms and this has triggered the new requirement for our main circuit breaker to be downgraded from 63A to half of that – 32A.
I am dreading this summer now and will likely have to run the bore and pool pump when we are asleep…meaning that we can’t take advantage of our solar power…therefore our electricity bills are going to increase as well….and put more load on the power supply..?? Crazy.
It’s a grossly unfair ruling on regional customers…and we all know it’s because the infrastructure is so poor in our areas and that it desperately needs upgrading!
Good morning Amanda,
I hope you have filed a formal complaint with Western Power and written to your local MP and the Energy Minister.
That seems to be the only way we are going to get any traction.
I’m really sorry (but not at all surprised) to hear your story: I hear it every single day.
Please engage with your local political representatives and the media. This situation cannot be allowed to continue.
That was my initial reaction too Amanda, but actually nearly a month in it has been no problem yet. I am on the Synergy “Smart Home Plan” so have 5 different rates Peak, off peak, shoulder, w/e shoulder and Export. The “Smart Meter” gives a reading at 30 minute intervals through all the previous days so I have used that to set the timer on my pool pump and heat pump, and HWS booster (family does not like “cold showers!). I run the aircond from mid arvo if the evening looks cool to pre-heat using any surplus solar + shoulder then minimised the peak draw.
As you say, Summer will be the test but my inverter is already maxing out at times during the day (battery is getting more interesting all the time).
Have not got my lathe and welder set up yet so some phase balancing may be needed -we’ll see… however, on the flip side, appliances are becoming far more efficient (inverter air-con, washing machines, frig & freezer, LED lighting, and so on, so perhaps it will not be as bad as it looks after the ‘teething period’. Needless to say, I will be logging every trip-out and lodging complaints. Computers and NBN modems rely on continuous supply and UPS have limited capacity. Time will tell. In the meantime I hope you are OK. Cheers.
Amanda:
On first read of you comments it seems you need to tap into an experienced RE System Designer who can give you some useful advice.
The key point is you have space and water [bore]. Take advantage of these points and you can slash your grid dependence entirely for several of your loads.
Firstly install a ground mounted Off Grid Stand Alone Solar PV System of around 10-20 kW and create a DC Backbone Bus from which any number of Power Conversion Devices can simply be connected to according to some of your Specific Services Loads.
For example: [A] Connect a VFD [Variable Frequency Drive] to suit your Bore Pump Motors [Single or three phase or Brushless DC; whatever], they can easily manage themselves with no demand on the grid.
[B] Same logic applies to a HWS or two. Run them from the Off Grid DC Backbone Bus.
[C] Irrigation Pumping is the same logic. Run an intermediate 1000-5000 litre tank filled from your bore, and use this as the replenishing/supply to an irrigation pump and Solar Variable Frequency Drive.
You are also eligible for STC’s to the full kW rating of the Solar PV Off Grid System.
You have many efficient and cost saving solar options at you disposal Amanda. Find the right system designer/integrator to discuss this stuff with.
Mainstream Solar system info trotted out everywhere, definitely does not represent the scope and breadth of good system design options available to Australian consumers.
Search and you will find.
Good luck moving forward Amanda.
Lawrence Coomber
Robert Bandura:
Thanks for your insights Robert.
Everyone should read your most recent post and reflect on it for a moment; and especially your comment “but against that (apart from today), the system was using grid power to recharge the battery first thing in the morning”.
Think about that very point and project forward: Does your situation represent a modern era [it is 2022] – RE, worlds best practice engineering / functionality power plant design?
All in favour, say Yes!
Your power plant design fails you miserably Robert.
Remember that: the errors; issues and weaknesses we blindly accept [in all subject matters – not just energy technology] becomes the standard that we embrace and perpetuate for all those who follow moving forward.
Lawrence Coomber
I forsee people wedging the breaker with a stick…
Tim, sorry but they now trip free of the lever. You could have an electrically-reset CB. I haven’t looked to see if the MCBs have these as an option.
I see two corrections in Kim’s article, now having read it the second time, (1) the mandatory breaker change applies to ANY electrical work – addition or alteration – it does not specify “major”. Secondly our WA “off peak” is 9pm to 7am, not 9am.
I have survived 2 months now without tripping the new 32A 3ph breaker in the meterbox but my 5kW Goodwe 3ph hybrid inverter is crying out for a battery as the output is flatlining at the limit several hours each day …
Have considered the Nissan Leaf 2 but the 10kW battery capacity – Any suggestions please???
Your blog contains a quote from western power that they would update you at the end of the year… did that happen? If so, can you please let us know what they said? If not, can you follow up with them? Thanks
Hi Larry,
Western Power are running a 6 month “trial” of an “increased” supply allocation from 32 amps to 63 amps.
Of course, it’s not an “increase” at all, but a return partway to the unrestricted supply allocation that was in place prior to Feb 2022.
Another problem is, the “trial” only applies to 6 Shires out of 75 shires that are affected by the 32 amp circuit breaker requirement.
Western Power have given no commitment to extend the trial beyond it’s end date in march.
Western Power have given no commitment to publish the results of the trial.
Western Power have given no commitment about whether they have any plans to make the “trial” permanent.
Western Power have given no commitment about extending the “trial” to the other 69 shires and 250,000 affected people.
That’s all there is to report at this stage I’m afraid.
Hello
What does the main breaker see? Does it just see the flow from and to the grid or does it see all of the house loads?
Reason for asking is if you have solar and a battery and these are serving behind the meter loads, is the main breaker seeing this and counting those amps or is it not and thus you have (for single phase Perth) 63 amps + solar amps + battery amps to play with (subject to each circuit limitation of course)?
Thank you
Adam
Hi Adam. Your main switch/circuit breaker doesn’t ‘see’ any loads directly serviced by your rooftop solar. For example: if your household loads were say, 80 amps (that’s a lot for an average home) and your solar was able to provide 30 amps then the shortfall of 50 amps would be serviced by the grid through your main switch. So yes it’s possible that your total household loads could be higher than the 63 amp main switch/circuit breaker and it wouldn’t trip – until that big cloud rolls over, then it’s lights out as the grid tries to take up the slack.
Thank you Kim. It’s interesting with a battery in this case. I can’t really see myself going above 63 amps but with an extra 5kW available behind the meter weather independent, there should never be a problem.
Hi Adam,
Just remember that the extra “weather independent” 5 kW you are factoring in from your battery, is only available while your battery still has charge (!)
If you’re like most home battery customers, your home battery will be flat after a couple of days of rainy weather.
Hi Andrew
The thought experiment arises because we dropped from 80 amp single phase main breaker to 63 amp and I was just confirming that the main breaker only sees the electricity coming from and to the grid. There would be the rare case I would need close to that 63 amps but if so I have an extra 11 amps from weather dependant source and 22 amps from a weather independent source taking me above my original grid connection for brief excursions.
Properly set up this would be a solution for rural properties with low amp and unreliable power to have extra power available and only be semi dependent on the grid.
One benefit we don’t receive in WA at present is reduce demand during periods of high demand. If as consumers we were given an incentive to reduce our demand during the periods when the reserve capacity obligation is determined, then it would reduce the contribution of our retailer and overall the amount of generation required (which we as consumers pay for).