Indeed but you can only export up to 5 but the whole system needs approval to export again once you have increased the production even if it still is only going to be the 5 you could export before the upgrade.
From the article
“keeping your connection as single phase, but installing up to a 10kW solar system with export limitation” (that limit being 5 kWh).
So you are part of the problem? 
(Seriously though only you know what that equates to in terms of generation and how that compares with your usage.)
I believe not. I believe it is simulating a mains outage - in both of its facets i.e. nothing in and nothing out. I haven’t dared to test that new option however. LOL.
On days when negative FITs are likely to occur (i.e. when any of this problem is relevant), power coming off the inverter would be limited to what can be used locally and the rest thrown away (wasted). On those such days, at the relevant times, it is unlikely to be the case that the grid would be needed to supply to me.
I think the rules vary between states and between grid operators.
Qld and with the 13.2 (-10 kWh at inverters total) we expect some 3-4 kWh at peak during the day export.
An interesting observation. Do you have a battery inverter and mains isolation?
My system has the capability to operate independently of the grid when the mains power is out. So when the mains power is out, the system can isolate itself from the grid (to protect linesmen) while still powering the house (to the extent of the available power, but on the sort of day when negative FITs would be in force the available power would almost certainly be sufficient to power the house). (I set this as a requirement when I was looking to get a PV install, due to the relative unreliability of the grid in my area.)
Hybrid inverter without battery.
The prior discussion has raised having to pay to export power. There is no need for an inverter to switch to an off-grid mode to prevent export. Most existing PV inverters can be upgraded with an added on external power meter to measure total household consumption. This provides for a no export mode setting. Our 3 yo inverter has the capability.
I’ve not seen any document suggesting consumers will be penalised by the application of negative FIT’s to solar PV export. Is this a misconception or speculation arising from the proposal to charge PV owners to export to the grid?
The ESB (Energy Security Board) has provided the following general advice on the future needs and direction of electricity supply.
There are significant recognised benefits from improving integration of rooftop solar generation and distributed/local storage.
Missing from the detailed discussion is a solution that allows residential consumers to monitor in real time power consumption or make informed decisions on exporting power?
Yes, speculation - because the details have never been provided.
However the original ABC article from March 24 linked from the ABC article from August 11 suggests that bigger PV systems (looking at you, @grahroll 
) will get hit harder than smaller PV systems. So that suggests that this is not a flat export charge used to fund electricity network improvements. It is of course possible that the ABC is not correct, given that the details have never been provided (and for a change coming into effect in 2025 that is somewhat understandable).
Whether this is implemented by actual negative FITs for selected periods of time or an across the board reduction in FITs … the effect is the same i.e. negative FIT notionally or actually.
The big difference between those two is whether you can avoid the penalty and avoid the “problems” for the electricity network by “going off grid” (/ export limiting) for selected periods of time.
Actual negative FITs for selected periods of time would be more “market driven” i.e. start to bring domestic generators into the dynamic pricing market.
The August 11 article also says:
They will not be able to impose flat fees, and charges will only be imposed when there is congestion on the grid.
Interpret that if you can.
Said article also says:
Power providers will be able to develop a range of packages for consumers to choose from, but they must include a “free basic service”, the AEMC said.
But Mr Barr said many people would find they would be financially better off choosing a paid option, because of the likely returns.
“If you don’t want to pay for exports, you don’t have to,” Mr Barr said.
So that suggests that AEMC has hospital-handpassed the blowback to retail providers and leave it to retail providers to shaft customers.
I think “free basic service” does not mean “free” at all. I think it means “a service that would be exempt from penalties for exporting” but no doubt clawing that penalty back elsewhere in the plan. So it seems as if there will also be an element of “confusopoly” and “information asymmetry”.
You may be right that there is an export limit setting somewhere, or there will be. However there’s a software Big Red Button marked “Go Off Grid” and who doesn’t love a Big Red Button?
Yes if charges start to be applied to export we would go back to only supplying through the inverters what our household uses and use a battery. Use of a battery however will incur the need for a three phase power supply as the battery inverter is considered part of the supply by Energex even though it will not be exporting and so will take us to 15 kWh which does require 3 phase under their rules.
Sad to think that the network has not been provisioned to use small scale production effectively but it is what it is, almost an anathema by Govt and Large Scale Energy suppliers to small scale production in a system of diversified energy production to support the grid. SA at least seem to have embraced the idea of VPPs in their energy supply mix.
A battery depending on capacity, can enable a consumer to hold back export from low demand periods. The ability to export any surplus energy during peak demand periods is likely a better strategy, assuming current TOU proposals or peak demand pricing is also reflected in higher FIT at these times.
As @person has previously suggested it’s difficult to forecast what the best strategy for consumers may be looking forward to 2025.
My guess only, a home battery will soon be more cost effective than grid connection for the majority of PV system owners. The greater the loss of incentive or penalty for having solar PV the more affordable the battery alternatives.
The proposed system and tariff changes over the next few years will need to be fair to and supportive of the large number of Australian consumers with rooftop PV. If not most will seize the opportunity to drop off the grid in one way or another. This will further burden those unable to leave the grid with sharing the cost of the grid across fewer customers. The same customers are also likely to see other added costs arising from the energy supply transition to increased renewable generation.
My guess: I doubt it. Although you did say “cost effective” and so that can ignore other considerations.
As far as I can see, there are three considerations for a battery.
As you say, who knows what the situation will be in 2025 but right now all of those could be problems for a random household considering going off-grid permanently (although the second is most uncertain). (It also depends on your latitude i.e. what works in Queensland may not work in Tasmania - but not because that impacts on the batteries.)
As FITs fall (either explicitly or in effect), and assuming that electricity usage charges remain as they are, the economic case for a battery improves - but that doesn’t mean that it changes from unviable to viable.
As FITs fall, the incentive to remain on the grid declines. (However there is also an inherent inefficiency involved. In order to be off-grid you will need to oversize your system, in order to cover days of poor generation, but that means that, without a grid to sell to, a lot of energy will simply be wasted in days of excellent generation.)
For a new housing development there is also the consideration that the cost to connect to the grid is a high visible cost. So what developers might do can differ from what an existing household might do.
While that is true, the cost to upgrade the grid to support household generation (this topic) would decline or disappear.
On today’s numbers, I doubt we will see a mass exodus. 2025 is anyone’s guess.
Some locales in the USA solved the problem by making it illegal to disconnect, or put up PV systems at all, or require certain aesthetics to be followed such as tile look panels. Although PV is seemingly a technical problem it was solved by political/governmental edicts.
… and mandatory to connect for new housing development?
My comment was of course predicated on the assumption that consumers are given free choice.
yes.
freedom, US (and others’) style, sometimes is the freedom to live somewhere else less restrictive/prescriptive.
With PV panels so cheap relative to the energy produced, it may not be an issue. Please excuse the speculation. I was suggesting there was a no win situation if Government decisions made it more attractive for consumers to drop off or withdraw from the grid than stay connected. As @PhilT suggests when it comes to future Govt decisions there is always the predictably unexpected .
I posted a number of links to recent reports on the strategic and some detailed assessments by the key Government Organisations responsible. It’s not certain that’s also how some Governments may see it. The suggested uptake of Renewables, and household PV by 2030 seem rather conservative. Follow to topic for links.
P.S.
We have 3 years of PV and consumption history. With the current differential between the FIT and supply tariffs, plus fixed charges, a battery system would be a looser. More than 60% of our current imported electricity (not discretionary) is in or close to peak periods. The exact future tariffs for peak usage or demand remain the unknown.
This is oddly UnAmerican. Still, perhaps we should worry about what is happening in Australia. For now at least, you do have the freedom not to connect and to disconnect.
As the FiTs reduce there are changes to consumer behaviour, measured and knee jerk. The FiTs were always ‘advertised’ as eventually going to zero and consumers responded eyes wide open discounting that in their purchase decisions. Now that it is happening there is some ‘shock-horror’ for them but it might be a kick up for battery installations regardless of the actual economics.
In Vic the FiT was $0.102 and current new plan offers are around $0.07. If reduced FiTs for existing plans start 1 October my retailer has yet to inform me but I expect a notice on the afternoon of 30 Sep as is often the strategy of delivering bad news.
Surely you don’t mean that? If the FIT is zero, that is theft.
FITs were at one time artificially high. FITs must ultimately reflect the wholesale cost to generate electricity, which is unlikely ever to be zero (averaged over, say, a year).
As the article says (as with petrol) the retail price never quite comes down as quickly as the wholesale price. 
In the coming years, the ACCC will no doubt scrutinise this in respect of electricity prices.
Whether getting a battery is the right response depends on the difference between buy price and sell price for electricity and the price of the battery. A far cheaper response could be simply to disable exporting. Yes, you will lose the revenue but the avoided electricity buy cost from getting a battery may never equal the cost of the battery plus the lost revenue.
However economics and policy need to recognise that consumers are not necessarily rational. Consumers recognise that the power is always with big government and big corporations, and so they may simply opt out - as their only way of exercising power and control over their own lives.
You may rationally get a battery for other than immediate economic reasons e.g. reliability of supply and e.g. as a hedge against future price changes.
A primer… now a bit dated, but. It focuses on the original programs but foretells the future.
The game is long since on where solar plans have higher costs to import from the grid than non-solar plans, and the amount paid for exporting is reducing over time, so it is probably closer to ‘net 0’ than is otherwise apparent.
An alternate strategy would be for solar PV owners to buy into shared local storage. The following project shows what can be delivered at scale. It also sheds some light as to the relative economics.
The economics in this example referenced per household.
Number of households serviced 40,000
Storage Capacity per household 12kWh
Peak Output per household 6kW
Average capital cost per household $4,250
Compared to a Tesla Powerwall the Mornington project delivers similar capacity at 1/3rd of the cost.
IE 11c per kWh direct cost of energy recovered at 90% trip efficiency and a single cycle per day over 10 years.
Compared to the current low wholesale cost of power during the day and premium paid for the morning and evening peak periods, the pay back period is open for comment.
It’s a more interesting prospect if residential PV owners were able to directly invest in their own shared capacity, rather than arms length as a shareholder.
One more challenge for the consumer with rooftop solar PV. Within the report are two items of concern. The first is progressive introduction of regulations to enable the operator to turn household rooftop PV systems off. The second is that rooftop PV systems shut down or reduce output in response to increased line voltage.
An immediate concern is that these actions penalise rooftop PV owners who have high self consumption. The penalty is indiscriminate and as severe as on those who oversized and export most of their generation for profit. It’s not a fair outcome. Those who were earlier adopters when the system was more capable are also penalised, as a consequence of the operators approving excess capacity of rooftop PV to be added.
Note:
Curtailment is a term used when the big network generators are required to reduce output below what they are contracted or able to provide.
Curtailment is most often for purely economic reasons where high cost generation is competing against lower cost generation, and there is insufficient demand to utilise all the available generation. IE Wind and Solar vs coal and gas.
Curtailment may be necessary to maintain system frequency (stability).
The use of curtailment is now being discussed in respect of grid connected rooftop PV systems. The challenges for consumers including reduced feed in benefits and having to trust the regulator is not favouring the big generators over rooftop production. The big generators have been caught out previously gaming the system, but only long after the fact and belated intervention by the ACCC.
