How To Beat Future Solar Export Tariffs

Zero export dilemma

From July 1st, NSW, ACT, NT, and Victoria will start to slowly roll out two-way pricing, with others in the National Energy Market (NEM) set to join in next year. This new setup lets network companies charge electricity retailers for the energy that flows back to the grid during busy times.

Lately, some headlines have made it sound like Aussies will be fined for sending their solar energy back to the grid. That’s not true and the Mainstream Media should know better1. Take the Ausgrid area as an example: the new tariff could drop your feed-in rate by 1.2c per kWh from 10am to 3pm, but only if your retailer passes this cost onto you. Right now, everyone in this area is making more than 1.2c per kWh for their exported energy, so its unlikely anyone in the Ausgrid area will be paying to export come July 2025.

While things are okay for now, we can’t say what the future holds. We might see negative feed-in tariffs down the line. If that happens, there’s good news—solar inverters can be tweaked to reduce or halt energy exports when it’s not wanted.

So, what’s the best way to avoid potential future charges on exporting solar power? Can we set up our solar systems to automatically cut back exports from 10am and then go back to normal after 3pm?

Inverters with Export Limitation

Most modern solar inverters can be export-limited, so the power they send into the grid is throttled. The kilowatts exported can be changed and even set to zero. That’s good news. The bad news is that it’s not time-based. The feature can be turned on or off but usually has to be manually enabled through the installer portal, making it impractical for users to adjust frequently to take advantage of ToU tariffs.

In addition, you’d have to invest in hardware such as the relevant smart meter (for consumption monitoring) and CTs (current transformers). On the plus side, if you don’t have a smart meter for consumption monitoring, you should get one!

Inverter export limiting

Read all about how a solar export limiter works here.

Catch Control

The Catch Control (formerly Catch Solar Relay) is a great way to divert surplus solar to a high-energy appliance such as a hot water system, minimizing solar exports. It can also export limit compatible inverters.

catch control relay

Here are a couple of options to deal with export tariffs using time-based control and a catch relay:

All inverters: Configure the ‘Export mode’ in conjunction with ‘Top-up mode’ to come on during the hours you want to avoid exporting. This will send surplus solar to your HWS or whatever load you have wired in. It won’t throttle the inverter however, and some energy will, no doubt, be exported.

Catch Control compatible inverters: The latest version of Catch Control can export limit (including zero export) a growing list of inverters. You can use a time schedule via the Catch app to set a zero export between 10am and 3pm.

Update: Catch tells me they are working on a feature that can be configured to know any new export pricing rules and intelligently switch on loads or limit exports to maximise the value of your solar.

Dumb Hot Water Timers

Speaking of timers, dare I say it, hot water timers may be dumb, but they’re smart enough to know when it’s 10 am, and your export tariff is kicking in. They’ve copped a lot of flak due to their inability to see when you have surplus solar at your disposal. But now, with export tariffs looming, if you can’t afford a Catch Control, perhaps it’s time to re-run the numbers and see if a good quality hot water timer is worth it.

Energy Management Systems

There’s a community of energy enthusiasts using the popular open-source home-automation software ‘Home Assistant‘ to control their solar inverters. This can include export limiting, depending on your inverter model.

I’m waiting for a HA (Home Assistant) guru to build an integration that switches a solar inverter to zero export, and off again, based on the time of day. The challenge is – it has to be idiot proof. Anyone?

Home Assistant webpage

Home Assistant guru wanted. Apply in the comments! Image: Home Assistant

Solar Batteries And EVs

A solar battery is certainly the weapon of choice for optimizing solar self-consumption. It’s particularly useful for avoiding peak demand tariffs and the new kid on the block – export tariffs. Most BMS (battery management systems) can be configured easily to charge at a specified time, soaking up surplus solar and minimizing exports.

The same can be said for your battery on wheels. In fact, if you’re lucky enough to own both a solar battery and an electric vehicle, it’s unlikely that these export tariffs will affect you much. Your charging regime is probably already on point, although in the context of impending export tariffs, it may be worth re-thinking overnight charging if you can do it during the day.

Manual Monitoring and Adjustment

Then there’s always the old-fashioned KISS (keep it simple stupid) method. Simply monitor your energy production and consumption throughout the day and adjust usage accordingly to avoid exporting excess energy to the grid during peak pricing periods.

This approach requires more hands-on, but unlike the other strategies, it’s free! And for a modest amount, you can do it remotely with Wi-Fi devices such as the popular Shelly smart home energy products.

East/ West Facing Solar Panels

East and/or west-facing solar panel orientation is looking more attractive by the day, and I don’t mean aesthetically. It’s challenging for many people to shift consumption to the middle of the day, so why not move your solar production around to align closer to your consumption? It’s probably not going to stop you from exporting solar but every bit helps.

East - west facing solar panels

Will we see more east/west oriented solar installations as a result of export tariffs?

Wrapping Up

While there may not be a perfect, integrated, time-based zero export solution yet, there are several ways to dynamically manage your solar exports. As the solar inverter manufacturers catch up, we’ll hopefully see more integrated solutions emerge well before anyone actually has to pay to export.

Footnotes

  1. I suspect they do know better but can’t resist the temptation for negative headlines that guarantee a good click through rate. “You’re gonna get fined for exporting solar!” will always get more engagement than “Your feed-in tariff might reduce by 1.2c before 3pm. From July 2025. Depending on your retailer. And only if you go over a kWh export threshold.”
About Kim Wainwright

A solar installer and electrician in a previous life, Kim has been blogging for SolarQuotes since 2022. He enjoys translating complex aspects of the solar industry into content that the layperson can understand and digest. He spends his time reading about renewable energy and sustainability, while simultaneously juggling teaching and performing guitar music around various parts of Australia. Read Kim's full bio.

Comments

  1. Chris L. says

    We need more community type batteries, cost much less than snowy 2 and much quicker to install. Why dont the retailers invest in this?

    • Jonathan Prendergast says

      Anything costs less than Snowy 2.0. Community batteries often are more costly per kWh than home batteries and big batteries. They are in an awkward middle ground for economies of scale.

      • Andy Saywell says

        While that’s true when measured in terms of immediate costs rather than a true ROI business case..(and please don’t mistake me for thinking a true one of those which actual had real numbers was ever done….) pumped hydro is likely to significantly outlast any type of electrical battery solution. It should still, on balance be fulfilling its primary purpose 100 years after being 1st being turned on…when ever that will be….

  2. Peter Fuller says

    How about just getting an appropriate battery with an over sized solar PV system (I already have two inverters and two sets of panels, 3 phase totaling about 16kw) adding a small backup generator (bi Gen or tri Gen) and disconnecting from the grid

    • Jonathan Prendergast says

      The expected impact of the Ausgrid charge is $6 per customer. It would not be worth investing an extra $30,000 to be off grid to save $6 per year.

      • Finn Peacock says

        Completely agree.

        • One of the issues is that people who have invested a lot of scarce funds in solar have seen their somewhat lucrative FiTs slowly whittled away and are looking at being charged to feed in solar in the future. At the same time, use tariffs are sky high.This doesn’t sit well, especially when the trajectory is negative. It all compounds to further the belief that major corporations will shaft us any way they can. It’s no wonder people feel like going off grid.

          Thanks for the suggestions in this article though 👍

      • George Kaplan says

        That’s assuming the Ausgrid charge is remotely valid. Using today’s results as an average for the year – sunny but near Winter solstice so low yield, you’re looking at closer to the $100/year cost than $6/year. Does that justify a $30,000 battery system? Well no, but then would you really need a 30 kWh system, or a 25kWh system + generator?

        And you’re assuming the costs don’t rise as Ausgrid try to keep household solar out of the grid.

        • Mark Bradley says

          If ‘off the water grid’, as I am, then a “25kWh system + generator” is necessary. I have a hotwater solar system, selectronic, 24kw batteries and a gen. When the Tamborine Mtn 11-day blackout happened on Christmas night 2023, over 4300 residences were without power and all were in a serious bind being off the water grid. For over 8000 people this meant no potable water per pumping water through filters and UV sterilisers, no showers and no laundry. For me the blackout was like nothing happened. Resilience is of critical priority to me. Having no power bills is a side bonus. As for winter solstice being low yield it was in the south (had PV in the ACT) not so in SEQ. It’s one of the reasons I left.

    • It’s a bit of knee-jerk reaction from a lot of people about going off-grid.

      It is simply not worth the cost doing so in urban areas. Bit like cutting off one’s nose to spite the face type of scenario.

      For starters, as far as I know, at least for Tesla Powerwalls, Tesla will not allow Powerwalls to be in off-grid mode if customers are within grid services (I can’t remember but it was something like a couple of kms from the nearest grid pole/wires). The only way to have offgrid mode permanently for Tesla Powerwalls is if one lives in woop-woop with no grid services available. Then it make senses to invest heavily in solar/battery/gas because the cost of getting grid services to the premise can be very prohibitive (I know someone who was quoted $100k just to get a single phase service brought in).

      Secondly, the grid was, for the most part, designed in the 1970s, 1980s when solar PV system did not exist for the masses. The grid was designed for one way flow.

      The issue with having too many local solar PV systems is caused by consumers as the inverters need to raise the 240v supply in order to export. Allowable maximum is 253V, once inverters push past this limit, the solar inverters will either ramp down or shut down to keep the voltage within specs, otherwise appliances will be damaged if the voltage is not kept in check. This is a not a distributor problem but a consumer problem. The distributors job is to supply a stable voltage of 230v +10%/-6% range. Consumers solar inverters can and do push this out of range. The distributors can not do much about it with existing infrastructure.

      Solutions:-

      1. Retrofit the transformers with AVR (Automatic Voltage Regulator), this will solve local grid voltage. Problem is that there are thousands of these things across the grid. It will be costly and time consuming to do this.

      2. Curtailment – already in place by AS4077 standards.

      3. Cost reflective incentives such as solar export tariffs to change consumer behaviour.

      • I often go off-grid just for fun, with my Tesla Powerwall and I live smack bang in the middle of Ausnet grid services. It’s in the app.
        Bob

  3. David Klemitz says

    Interesting, no mention of SA.

  4. Mark Stokes says

    For those of us already exposed to negative FIT via Amber Energy, but not ready to spend all our time programming Home Assistant, the Village Energy Voltello Link ZB looks like a simple way to curtail the inverter and reference the market price using an API feed from Amber Energy. So no need for time of day control it just curtails to zero export when the FIT price is negative

    • The following is what Amber are telling me in a email

      “At the moment, we aren’t charging customers when the solar FiT is negative across a billing period, so instead we introduced the FiT floor pricing of $0 if your average FiT is less than 0c/kWh (note that this may change in the future). You’re still being paid for solar exports when your average FiT is above $0.”

      So I have to wait until the end of the billing cycle to see just what the above translates to. I have a SolarEdge inverter without a battery which Amber claimed you could do load shifting with. The product is called “SmartShift”. Have not heard a peep out of them in 4 weeks.

  5. We had a 315 litre Rheem HWS installed with our new house build last year. (Yes, contrary to what many say, you can have them in SA if you have a minimum of 1kW of solar panels on your roof.) One advantage of being retired is that you can turn on the HWS at the sub-board when solar production gets above 3.6kW. Fronius Solar Web lets you see on your phone or laptop what your production and consumption is in real time. It would be great to have an electronic switch that can be used remotely using wifi if one isn’t at home during the day. Is there such an item that can be installed in a sub board that doesn’t cost the earth and that will talk to a modem just like the inverter does?

    • why bother with all that sophistication when you can just run the HWS off the solar panels and dispense the controlled load tariff ? Doesn’t Fronius have an equivalent ?

      https://knowledge-center.solaredge.com/sites/kc/files/se-home-hot-water-controller-datasheet-aus.pdf

    • I say all solar system users should turn off their solar systems and see how the grid will crumble without us.

      So many lies and spin..

      • Now that’s one way to put the power back into exporters hands 👍

      • Andy Saywell says

        Yes….lets call it night time….

        and don’t hold your breath waiting for a crumble to oocur….statewide bad weather achieves the same outcome and no real crumble to be seen…..some significantly higher spot market prices will be paid to those that we in the PV world most probably don’t want to see collecting like the big O and the big A..

    • You can set this up on the Fronius inverter itself under LOAD MANAGEMENT.

    • I built a control box with a timer and a contactor to switch my HWS on and off. Cost around $100 using parts sourced from a reputable online electrical wholesaler. The HWS was disconnected and a new cable run from a 15A GPO via the controller to the HWS. It comes on at 1100h and turns off at 1400h every day when solar is producing max output here in central coastal Queensland. The HWS was wired via the off peak circuit and meter which was removed when the solar was installed March last year. This meant it was heating at off peak times using on peak rates. Haven’t had a power bill since May last year. We have a 10kW system with two Fronius Gen24 inverters.

      I’d suggest that if you know what you are doing, this may be an attractive solution.

      • Anthony Bennett says

        Hi Matt,

        I’m glad you’re coming along with us on the sustainability journey, I’ve always marvelled that solar gives people the tools but also fights the sense of apathy they have in saving themselves some money. It’s a win for everyone, even the science deniers and troglodytes.

        I should point out that fixed appliances like your hot water service should have fixed wiring installed by an electrician, otherwise your insurance is void. A few people claim to know what they’re doing, but end up creating dangerous situations for themselves and others.

        There are some really good power diverters available for harvesting solar into resistive hot water, but if you have enough yield, a relay (like catch control) and a smaller element are nearly as good.

  6. Related Home Assistant project here:
    https://community.home-assistant.io/t/solar-curtailment-on-dynamic-prices/561876

    This is based on hourly rates (dynamic contract), but similarly it could be done based on time as well.

  7. Michael Boland says

    I haven’t seen much discussion on lowering the price of electricity during periods of excess (solar) energy in the grid as an alternative to lowering feed-in tariffs to drive consumption of lower cost energy and flattening the “duck curve”. Whatever happened to using “market forces”? I expect it would put more stress on conventional coal plant economics for them to match even lower rates during the day, driving an even faster demise, which could be why this option is not raised.

  8. I have 11kW of solar and a Powerwall 2. As I am export limited to 5 kW, I have wanted to find a way to control my battery charging til the middle of the day to maximise my exports. Is there some way to do that with the Powerwall. I haven’t been able to work out a way to do it.

    • Ditto, but have Sungrow Hybrid and *supposedly 19.2kwh of Sungrow battery.
      And I have had this discussion with one journalist who’s articles reckoned we battery owners could simply charge them during the middle of the day and then discharge to grid in peak demand, because this is what her “industry experts” told her. What a lot of rubbish. Neither is possible for the home owner with Sungrow and probably isnt for any other brand either.
      When pushed she said her expert had sad the “software isnt perfect” !! NOT PERFECT, you just cant do it.
      I will send her the link to this blog.

      *That’s another tale.

    • My Tesla Powerwall 2 will start charging whenever there is excess solar.

      Once it is finished charging at a max rate of 5kW, whatever excess is then dumped onto the grid.

      Isn’t this how your solar installer wired up your system?

  9. Wouldn’t be surprised if when v2h is perfected a lot of people will go off grid !!

  10. Michael Costello says

    What gets me is that it will apparently be between 10am – 3pm. Yet, at the same time, between 2pm and 8pm, from 1st April until 31st October I am being charged a demand penalty for using electricity.

    So, between 2-3pm for 7 months of the they are penalising me for using electricity while at the same time crying that there is too much power in the grid.

    I’m truly not that stressed as I currently get 12c for the first 15kWh and 7.6c for the rest and my bill is $1000 in credit (had 12.8kW solar installed Nov 2022). It’s just the stupidity of penalising for use between 2pm – 3pm while at the same time crying there it too much power in the grid.

    • Hi Michael

      I’m calling that demand tariff the “Dinner Tax” ’cause if affects all those families trying to cook their dinners in their all electric kitchens. Especially those that don’t have a battery.

      • Finn Peacock says

        How Ronald dodges the ‘Dinner Tax’:

        • Hi Finn

          Ha!!

          Eat out of a slow cooker for 30 days and tell me you still like it.

          Want a roast dinner on Sunday – better have it for lunch otherwise you’re paying the Dinner Tax.

  11. Forever the pedant: :>

    Perhaps the homeowner of the east-west configured solar panels in the bottom picture would be better served financially by considering moving their satellite dish, before worrying about solar export penalties.

    • They are most likely using Enphase micro inverters or panel optimisers. Hence, they didn’t bother relocating that pesky dish prior to solar installation.

  12. Anoop Philip says

    While excess PV diverters are the best option, it may come with a long payback period due to high initial cost.
    There are also products which are more than just a water heater on a timer like the Thermann Smart Electric.
    In addition to be able to set schedules on the App, it comes with additional features like;
    1. Multiple operating modes including holiday mode

    ****I’ll stop you there Anoop – next time please disclose that you are a product development manager for Thermann… FINN****

  13. Textminer from WA says

    It’s perplexing – why would the good citizen of Australia even bother with any other scenario than self consumption. The entire ‘solar industrial complex’, certainly so far as residential solar is concerned, is in disarray –> lurching from one fix to the next reaction, then fixes on fixes, and reactions to reactions …. The system is broke, and it will drive people to disconnect. The only more stupid thing than paying to export is paying for no energy used … an imputed energy use tax (as one-time treasurer Keating would dream up) — don’t laugh — it may well come to that. What a clusterfuck!

  14. Joan Spelling says

    Hi Guys
    The catch all or catch control does not work on 3 phase , single phase only

    • Anthony Bennett says

      Hi Joan,

      Catchpower have a 3phase model coming very soon they tell us. I believe it exists and they’re doing some beta testing before it’s released.

      • Uncle Phil says

        I can’t understand anything you’re saying. It’s completely possible to charge during the day and discharge during peak. That’s how Amber is set up to work best and it’s how my system works. Sungrow can definitely do it with Home Assistant automations. If you send her a link to this “blog” you’ll be confirming she’s right and you’re wrong, though I’m sure she won’t mind at all.

  15. Solar feed in is now pointless – it’s only.worth a little when there’s no sunlight.

    Coal and gas wins, unless nuclear gets up again..

    Has anyone ran the figures on a community diesel generator instead of grid? It ain’t green but it’s running costs are known. Wholesale costs of $20 per kWh during a spike are just not realistic.

  16. There is a thread on the Home Assistant Community Forums (“Automate Fronius Soft Limit”) where people are using modbus control to adjust the Fronius export limit. Most of those doing it are Amber customers.

    It does not look too hard to set up the modbus control, and if it’s a simple time based trigger (e.g. no export from 10-3) then that would be pretty straightforward.

    But no “idiot proof” universal solution.
    One should never underestimate the ingenuity of idiots.

    So it’s certainly an option for those with Fronius inverter and Home Assistant (like us).

    I’ve bookmarked for future reference as the reality is:
    – negative FITs for regular retail plans are unlikely, at least not for some time yet
    – we’ve embarked upon a journey of load automation to maximise self consumption. Water heating, off-grid battery, EV can all suck down the juice almost at will, and match available excess PV generation capacity.

  17. This morning’s news says AEMO is predicting blackouts in SE Australia over the next couple of summers, yet solar exports are curtailed and export tariffs being imposed for exporting solar to the grid.
    This is in summer when demands for air-con, pool pumps etc will be at their greatest.
    I hope someone with more expert knowledge than me can explain this.

  18. Don Culey says

    Back in the dark ages, when nearly all electrical power was supplied by coal generators, there was a problem.
    During the day most power was used by industry and offices, in the evening was used by homes, and in the early morning there was an excess of power that needed to be used. This was partially accomplished by pumping water using pumped hydro as a storage device, but the smart engineers in the developed a system to “soak up” additional power and at the same time supply cheaper power to the end users. This was at the time called “off peak” (now morphed into controlled load). This was turned on and off controlled by the distributors. By using the controlled load they were able to “smooth out” the load on the grid (back decades ago).

    So this brings me to my question, why is it the talented modern grid operators are not smart enough to use the controlled load to assist in changing the load paramaters of the grid and “soaking up” the additional energy that is being supplied by solar during the middle of the day. Surely this would only take a small change in the timing of the ripple controllers (and smart meters) and the infrastructure is already there.

    I believe that using this 1950’s technology from the smart engineers of that time, would surely assist in balancing out the usage and generation of the grid. (or am I missing something here)

    PS retailers would even be able to make money out of this by using power when the wholesale price goes negative.

    I look forward to receiving a reply as to why this cannot be done.

    • A lot of people are shifting their biggest energy appliances away from controlled load tariffs. (I did in 2013, and put my HWS on a WiFi switch which can be now be programmable via Home Assistant).

      I know that Endeavour Energy (a distributor in NSW) has been trialling OffPeak Plus in certain areas to shift hot water heating to times when there is excess energy in the grid for a discounted rate. However, this requires a retailer to be engaged to offer this tariff. Not all retailers can do this. It should be mandated that all retailers offer all the tariffs available by the distributors.

      It’s either people not being aware, not savvy enough or too lazy to change their energy usage.

      There is no financial benefit for distributors to shift consumer’s loads and in the early days, when distributors were retailers, they would have been offered low rates to put hot water heating in the middle of the night so that the “baseload” generators can keep running during low periods of demand. But that’s not the case anymore. And exactly what is baseload these days?

      Controlled load devices (ripple control/Zellweger) will become a thing of the past. Distributors are slowly not allowing new connections to have controlled tariffs, and the consumers either be on ToU, SToU or Demand tariffs.

      • Hi Graham, you write “A lot of people are shifting their biggest energy appliances away from controlled load tariffs. (I did in 2013, and put my HWS on a WiFi switch which can be now be programmable via Home Assistant).”
        This is exactly what I am interested in. It must be a fraction of the cost of a Fronius Ohmpilot, but even my PV installers didn’t seem to know what I was talking about and they are a very reputable company. Can you provide further info on both the Switch and ‘Home Assistant’?
        Against my wishes the builder’s electrician last year had a controlled load meter installed in our meter box. It doesn’t do anything. When I asked ETSA Utilities if they’d like to have it removed I was told it would cost me a couple of hundred dollars to do so and just to leave it there. The builder’s electrician also installed a controlled load Night-Off-Day switch in the sub board inside the house, but it doesn’t seem to do anything either. I’d like to replace it with a WiFi switch. I live in Adelaide.

        • Uncle Phil says

          Home Assistant – just do a web search. It’s a very popular home automation system, open source and hence very cheap. Helps massively if you’re a nerd (guilty as charged). Lots of switches that can be controlled by it, or by their own control software. I’d recommend you install a proper contactor and control that via the WiFi switch rather than using the switch itself. Don;t worry about the meter, who cares if it’s there? Just have Off Peak removed from your tariff when you move the HWS connection. You’ll be saving quite a bit just be doing that as there is a daily charge for that part of your tariff – it’s a money-making opportunity these days.

    • Simon Jowett says

      I’m with Origin in NSW and recently received a e-mail saying my controlled load timings will be actively managed to deal with this issue. It’s taken forever but it seems they are getting there!

  19. When is the promised dynamic export limits being rolled out in Victoria? Supposedly 1st March according to solar quotes blog post.
    I have a compatible inverter but am still limited to 5kW maximum export.

  20. Alexander says

    As an Amber customer, I see that just when my batteries are full and I have an exportable surplus, is when I can expect a low or 0 cent FIT. What this tells me is that the grid has a surplus of solar PV! Better buy just enough PV for your own needs and a battery for evening peak prices.
    If you can cope with a bare-bones battery, it will cost 30% to 50% of a Tesla PW2. Check out this site https://diysolarforum.com/

  21. Greig spencer says

    Are they really serious ? Between 10am and 3pm is the only time most solar panels work.
    I have my pool pump and my spa operating during these times, and anything else that can be done. I’m doing my bit to use power during the middle of the day when my panels are producing their maximum…..very hard lately with lots of rain though..
    So, they are saying they don’t want the power from household solar panels ?

  22. I would have just one remark.
    Since we lost Rudd government our feed-in tariff are going down and down and down….
    Anybody really believes this is the best way to go to achieve our goal with 100% renewable energy?
    It is obvious that this is not in everyone’s interest and our government of the day will do nothing to stop this trend.

    • Joseph Viviers says

      I do not have the data or breakdown of the renewable energy supply over a 24 hour period. I assume however that solar is a major supplier for 10 to 15:00 in the winter and somewhat later during summer. Wind should be 24/7 when available. In my view Snowy 2 and the Marinus link should suck up a lot of power during the times of excess and the provide it back during the times that solar is not providing. Together with the big batteries I would have thought that they would want as much as possible power to store it for later use. I know it is a. Bit off but is should be operational for Marinus late 2025 and snow possible in 2028. I have a bad feeling that it is all about making money.
      In my case I will fit the biggest system I can get on my roof and add a big battery and just export enough energy to cover my daily supply charge from the energy company. I also have a feeling that the daily supply charge will keep on climbing in order to make money. Victoria already have 33 energy suppliers and they just keep on increasing as it is a money printing machine for them.

  23. Michael Paine says

    Hopefully Tesla will add more intelligence to the Powerwall & Gateway to throttle feed-in during times of surplus grid power. Fortunately we also have the option of charging an EV at these times (but the Powerwall thinks it is sending surplus solar power to the grid due to the EV charger configuration that avoids the Powerwall charging the car directly).

  24. Uncle Phil says

    I have my Enphase micro-inverter system set up to throttle based on export price (Amber electricity). It’s not super hard, though you need a (minimally) co-operative installer or the patience to get Enphase to give you installer level access to your system so you can configure it (not the preferred option in most cases as it would allow you to do something illegal if you were so inclined). If you just wanted to zero export based on time with Home Assistant, it’s easy and cheap to do. Plenty of other Amber customers do the same with other inverter brands, depending on the inverter. If you want to know how to do it with Enphase, get in touch and I’ll tell you.

  25. Wait… So let’s get this straight…

    We need to increase our electricity production to cater for higher demands with ev cars etc.

    But now we’ll punish people for increasing electricity production. So instead of increasing supply, lowering the price and making manufacturing cheaper, we’ve decided to limit supply…. Classic.

    This is madness to the highest degree. It makes absolutely no sense for anyone who consumes 10kwh a day to even bother installing solar.

    The FIT in Vic went from 12c, to 10c, to 6.7c, to 4.7c? To 3.3c and they want to make you pay 1.2c in two years time, so someone would probably get paid a fit of 2c and have to pay 1.2c, less than 1c lol, yeah no thanks.

    Sad it’s come.to this, this is what happens when you sell off your assets for privatisation

    • Uncle Phil says

      No, it just means it makes no sense for you personally to do solar without storage, though there are some plans that might make that untrue. However, don’t make the mistake of assuming that your usage patterns are universal or even common. If you work from home three days a week, for example, and drive an EV those solar panel will be eliminating your petrol purchases for the rest of your driving. Or maybe you have a pool pump, use dryers a lot, can run your washing machine on a timer and run your HWS from your solar. Any load you move to the solar production period saves you the cost of buying that electricity, which is an EFFECTIVE feed in rate of whatever your mid-day electricity charge would be. It’s only useless if you just buy them, whack them on the roof and don’t bother doing anything else.

  26. Mark Purcell says

    Zero Export mode is straight forward with SolarEdge inverters and Home Assistant.

    Here is my automation, when the feedin price goes negative, I switch to zero export mode, when the feedin price goes positive I disable export mode. I’m using this with Amber, but it will work with any retailer.

    https://community.home-assistant.io/t/emhass-an-energy-management-for-home-assistant/338126/1216?u=markpurcell

  27. I love the way “change consumer behavior” is used on this forum as a good thing. What gives private companies the right to “change consumer behavior” by charging them more. Say Woolworths and Coles decided to put their prices up on Sundays to “change consumers behavior” would that be ok.

    Whilst I’m on the soap box another instance of changing consumer behavior is the peak demand charge. This one I call the dinner tax because it’s squarely aimed at people who come home and prepare their dinner in the all electric kitchen. So, oven goes on, maybe the microwave or yeah the induction stove top. What are we using 6kW * Rate 8 number of days in the month. Excellent we have just been charged $54 for electricity we’ve already paid for.

    And if you say just change your plan, if you’re in an Ausgrid area with a smart meter it’s almost impossible to get a retailer to get you a plan that doesn’t include the dinner tax.

    And whilst I’ve got a minute left of my time on the soap box – what about Ausgrid and others determining the size of the solar installation you can have (by inverter size). So if you want to put some extra panels facing East to take advantage of the morning sun – no way that’s over the 10kW.

    • Anthony Bennett says

      Hi Chris,

      Having a fixed price on something with variable availability is a recipe for horrendous expense.

      Electricity authorities have always used price to change consumer behaviour, with off peak tariffs.

      Eg Electric storage hot water services were set to use energy overnight. Instantaneous electric hot water would be more efficient but standing losses in tanks were ignored. The customer paid for the leakage involved with storing hot water and the grid operator/generator got to run their equipment overnight without the metal fatigue and inefficiency of stoking boilers up and down twice a day.

      https://www.solarquotes.com.au/blog/stealing-electricity/

      If you’re really upset about, installing a decent solar and battery setup means you can have as much capacity as you like and zero export.

      https://www.solarquotes.com.au/blog/selectronic-sp-pro/

      I’m more inclined to help people think about the grid as a common good.

      https://www.solarquotes.com.au/blog/sa-off-grid-renewables/

      • Hi Anthony
        Thanks for replying to my rant.

        You make a good point re off peak tariffs. Off peak was a lie to make money out of what would be wasted production so we can probably say that companies will try to change consumer behavior in order to improve their bottom line. This is exactly how I see the upcoming tariff and the “Dinner Tax”.

        Thanks for those links.

        1. I have no problem with Time of Use tariffs – the only rip-off is the “Dinner Tax”.

        2. That setup sounds great and if I had read it 5 years ago I might have a different setup. As it is I have enphase microinverters that have reached Ausgrids limit and I cannot add any more panels. They don’t even give you the option of adding more and limiting grid output.

        3. The things that have been done in the name of the common good. I think all those who have put solar on their roofs have contributed to the common good even if that wasn’t their intention.

        • Anthony Bennett says

          No worries Chris,

          Sometimes people just need another lens given the transformation we are going through.

          As of two days ago I think(?) Selectronic have been certified as what will be defined as an “independent supply” under the new version AS4777. Sadly they won’t let you export form the DC side so the batteries aren’t going to be a resource for the grid, however you can have any amount of solar you like downstream of the SpPro. For your place it might be feasible to run the enphase as a grid connect and have more solar added later.

          The battery will see you avoid the demand charges and provide a bulletproof supply in an outage. It won’t be cheap but it’ll be good.

          I think the best thing we could do would be nationalise the electricity grid, and they can train people like they used to.

          • Beau Roberts says

            Hi Anthony, for some reason the ‘reply’ button was not present on your reply below to my original comment, so I had to reply to this comment instead.

            Yes, glad you understand the reality of thermal generators. Unfortunately the very situation the operators were hoping to avoid is now a daily reality. In NSW you’ll see the coal generators sit around 5-600MW through the night where renewables are nearly non-existent, ramp up to 660MW for the morning peak then down to 200MW within an hour where they sit until about 4pm.

            Another ramp up to 660 for the evening peak then the cycle repeats. Boiler tube leaks are a frequent occurrence now because of these abnormal conditions, hastening the demise of these already creaking plants. We need firmed renewables yesterday to address this, preferably with much better building codes to increase energy efficiency and a compulsory rollout of TOU meters to address the duck curve via price signals.

          • Anthony Bennett says

            Thanks Beau,

            Sadly the thermal industry hasn’t seen the writing on the wall, neither have their cronies in the pervious federal govt.

            Electrification of transport is going to help a lot because the available battery storage will be massive.

            Buy a 40kWh battery and get a free car! If we get enough of them, (sooner than the generation/interconnection transition) there will be a lot of overnight demand until things are properly settled.

        • Beau Roberts says

          “Off peak was a lie to make money out of what would be wasted production”

          That is simply not true at all. There is no ‘wasted production’ from coal fired generators, or any generators for that matter. The generators are ramped up and down according to network load by reducing the rate of coal fed into the coal mills by the gravimetric coal feeders.

          The off-peak controlled load concept was designed to reduce the damage caused to plant by severe thermal cycling, and to prevent costly network upgrades by shifting appropriate loads from periods of high consumption to periods of low consumption.

          • Anthony Bennett says

            You’re right Beau,

            What many don’t realise is that stoking a boiler up and down costs money in metal fatigue and maintenance. We all used to pay for that when the networks were government owned. So off peak was made artificially cheap just to keep the wheels turning and spread costs.

            We still need the costly network upgrades because peaky demand profile is driven by sh!tty building design and people who demand refrigerative air conditioning.

            Everyone ignores the fact that using thermal storage to shift consumption involves standing losses, which are paid for by the end user.

            Luckily the solar duck curve needs flattening, and thermal storage will be good for that.

            (I believe outright efficiency would see us using heat exchangers in shower drains and instantaneous electric hot water)

    • Hi Chris,

      Taking into acount your self proclaimed “rant”, to be honest, what you’ve said about Ausgrid sounds like they are fair (in a large corporation sense).

      On the feed-in limit, the 10kW feed in limit is per phase. So you could do 30kW if you are willing to invest in the infrastructure to provide it to the grid fairly. It is reasonable they want the phases balanced when someone’s system becomes larger.

      I’m a bit surprised you are stuck on a “dinner tax” tarrif. I’m in Ausgrid with Solar only 15 months old with a flat rate tarriff plus controlled load. That might be because of luck. Our retailer changed our meter because they wanted to about 2 weeks before solar was installed rather than the other way around. I think the Ausgrid rules say you can at least request to move to Time of Use after 6 months on Demand tarriff. Might be worth a chat with your retailer.

      Lastly, on the “private companys” the “right to charge” and “change consumer behaviour”. You are partly correct. They are not doing it to “change consumer behaviour”. They are moving to a user pays system. Consumers can change their behaviour or pay the costs of what it takes to continue providing their current usage patterns. While they are a monopoly, they at least have a right to charge customers what it costs to provide to that customer. It costs to provide that peak to those who insist on cooking dinner without thought of their peak usage in a small window. That cost is either borne by everyone or only by those who contribute to the problem. Whether it changes consumer behaviour or not doesn’t really matter. At least the consumers who don’t adjust are the ones who pay for it and it gives consumers options to avoid paying for the gold plating of the network for the sake of a 30 minute local peak. For an article on this effect, search for the power surge caused by electric kettles at the end of the TV show Corination Street in the UK!

  28. While I’ll probably cop some charge (well my retailer changing things a bit to hide an additional charge to them), things are moving so quickly that investing now in something additional like battery or Catch Control (doesn’t stack up for me due to the control load rules under Ausgrid) for some marginal saving doesn’t make sense.

    I’m waiting for V2H, V2G to be a real thing as I can leverage one investment for multiple tasks. I think that will solve a lot of things for me all at once.

  29. Thanks for another well reasoned article Kim. With respect to “Most BMS (battery management systems) can be configured easily to charge at a specified time, soaking up surplus solar and minimizing exports”, I had a Solaredge battery installed last week and had hoped to be able to have the ability to change battery operating modes, inclusive of time of use scheduling, at will via their battery management app. All their website information & videos say as much, however the functionality doesn’t exist in the real world; “it may be availble soon” according to a Solaredge engineer I spoke with. In the meantime, if I wish to change the battery’s operating mode from it’s current setting, I have to call my installer who then places a request to Solaredge – that’ll be popular with affected installers once two way pricing rolls out !
    Have I been misled by the Solaredge website info, or have I “misunderstood” (puzzled emoji)

    • Thanks for your interesting response

      ” I had a Solaredge battery installed last week and had hoped to be able to have the ability to change battery operating modes, inclusive of time of use scheduling, at will via their battery management app”

      “however the functionality doesn’t exist in the real world; “it may be availble soon” according to a Solaredge engineer I spoke with. In the meantime, if I wish to change the battery’s operating mode from it’s current setting, I have to call my installer who then places a request to Solaredge – that’ll be popular with affected installers once two way pricing rolls out !”

      That is what concerns me about a (solarEdge) battery. I have a solarEdge inverter so it is reasonable to suggest that extending the same platform would lessen the impact of any integration issues. Hot Water Controller too. However as you point out, how do you stop yourself from being caught between a rock and a hard place (installer and solarEdge engineer) to realise what are really pretty basic configuration issues.

      imho you do not need to involve the installer every time you want to change the functionality as discussed. You would think the solarEdge person would be able to do this over the cloud with suitable access. Or of course the phone app. Just out of interest, what state are you in . Any ideas gratefully received.

      “the menu is not the meal” RD Laing.

      • Michael Costello says

        Hey David
        I have the SE battery and currently have the Time of Use settings available as part if a trial, so hopefully soon.

        Cheers
        Mick

  30. Solaredge’s battery profile programming delivers the goods David – https://knowledge-center.solaredge.com/sites/kc/files/storedge_charge_discharge_profile_programming.pdf
    Mode ‘Discharge to maximize export’ could be used until the solar peak time period begins, then switch to mode ‘Maximize self-consumption’.
    It doesn’t look that tricky so I wonder why customers aren’t trusted with it ?

  31. Michael Costello says

    I’m part of a trial at the moment and the only settings available are Maximise Self Consumption, Time of Use, and Backup Only. No idea why we aren’t trusted with a more complete version of the settings.

    There is a guy in England who seems to have access to a whole lot more.

Speak Your Mind

Please keep the SolarQuotes blog constructive and useful with these 5 rules:

1. Real names are preferred - you should be happy to put your name to your comments.
2. Put down your weapons.
3. Assume positive intention.
4. If you are in the solar industry - try to get to the truth, not the sale.
5. Please stay on topic.

Please solve: 22 + 5 

Get The SolarQuotes Weekly Newsletter