A Sungrow Hybrid Inverter connected to 6.6 kW of solar and 12.8 kWh of Sungrow batteries. And a dishcloth.
As a solar installer in Australia, I’ve looked at many Powerwall alternatives for residential battery storage systems. In this guide, I want to share my knowledge about using hybrid inverters for grid-connected solar battery systems.
Hybrid inverters are an alternative system design to ‘All-In-One’ battery units like the Powerwall. One of the best things about them is that they allow you to legally add more solar panels than your local electricity network usually permits. That’s a massive advantage in bureaucratic Australia, especially if you want to maximise your solar generation.
Hybrid solar/battery inverters manage solar power generation and battery storage in a single unit. It streamlines your solar setup, and if you’re buying solar and batteries together, it can save you money on hardware and installation.
Most of this post will give you the information you need to buy the right hybrid solar/battery system for your home. Buying a solar and battery system is much more involved than simply buying solar, and I want you to go in with your eyes wide open so that:
- you get the right-sized battery and hybrid inverter
- you get enough solar to charge that expensive battery all year round,
- you get your bills as low as possible
- your system backs up the appliances you need when the grid goes down
- your system can recharge from the sun in an extended outage
Towards the end, I’ll give a curated list of Hybrid-inverter powered Powerwall alternatives available in Australia.
Note: If you’re interested in a battery system that doesn’t require a hybrid inverter, you should check out my previous post, where I explore ‘All-In-One’ Powerwall alternatives. – where you get one main unit with its own integrated battery inverter that ‘AC Couples’ to existing solar systems as a simple retrofit.
Two Things You Need To Know Before Buying a Hybrid Battery System in Australia
Here are two links you should read before you start worrying about specific hardware:
- First, you need to Know Your DNSP Inverter Limits.
- Secondly, there are strict rules around battery locations rules that can be a showstopper for certain options.
Do The Maths
If your bills are too high despite already owning solar, there’s no point just throwing money at a battery and hoping that will fix your bills.
The new ‘solar cowboys’ on the block are now knocking on your door or posting you unsolicited mail implying that a bolt-on battery will cure all your energy ills. Just like the solar-panel cowboys, they can’t possibly make that claim without seeing your unique energy import and export data.
Before you spend thousands on a battery, you need to get a consumption meter, or look at the one you already own. It can show you the best way to invest your money, whether that’s more solar or batteries (or efficiency). A good installer can help here.
Better still, devices such as Solar Analytics can use your actual solar and consumption data to:
a) do the sums for you – advising on the best-sized battery for you and the annual savings it will give
b) choose the best retail electricity deal with or without that battery. As retail plans become more complicated with seasonally adjusted, super off-peak, off-peak, shoulder, peak and demand charges, this is becoming impossible with a back-of-the-envelope calculation.
If you have a vintage solar system without monitoring, your retail smart meter lets you access your ‘NEM12 data’. This data typically covers half-hourly meter readings for 12 months.
Look For Reliable Warrantors
If you want to knock yourself out with warranty fine print, my fellow blogger Ronald has got you covered with his deep dives into Sungrow warranties, the Powerwall warranty and many others. But as Ronald always advises – the organisation providing the warranty is more important than the warranty fine print. And that’s because the retailer must provide a reasonable warranty under Australian Consumer Law – no matter what the manufacturer writes in their warranty document. The organisation providing the warranty is the one that takes your money for the system – the solar retailer/installer. So choose your retailer/installer wisely.
Use The Same Inverter And Battery Manufacturer Where Possible
If possible, prioritise a hybrid with an in-house battery over other compatible models.
From my personal experience, I can share that when Victron replaced an entire model range of inverters under warranty, their relationship with LG Chem soured, and the warranty support for existing installations was left in limbo. This was the solar retailers’ problem, not the consumers’ problem – but it still caused headaches all round.
Interesting tidbit: I’ve been told Tesla dropped their ‘DC-coupled’ Powerwall 2 model because of the shit fights they had with third-party battery inverter manufacturers with the DC-coupled Powerwall 1. They settled on the AC-Coupled Powerwall 2 that could be retrofitted without any third-party inverter.
Hot Water Is A Battery Too
We mustn’t forget that hot water is a great way to store energy. Using your existing hot water as a solar battery can drastically reduce the size of the ‘real battery’ you’ll need.
I’m still a big fan of old-fashioned storage hot water systems. In many cases, it’s a battery you already own. With only an element and a thermostat, they are perfectly simple, there’s just one moving part, and unlike a heat pump, the whole system is covered by the same warranty without exclusions.
This system has a hard export limit. But when the hot water tank needs a boost, lots of solar is self-consumed – not exported – so the generation can go way over the export limit kW.
Adding a contactor to automate your hot water service often makes sense. Many solar inverters have relay outputs to divert solar yield, or you can have a Catch Power Diverter or Catch Power Relay for additional monitoring smarts, which is especially handy for legacy solar that doesn’t have an app.
It also makes good sense to overhaul the switchboard at the same time. In fact, many installations don’t have enough space to install the required gear. You may need to remove old mechanical meters and condense old two-pole or four-pole safety switches into single-pole units that offer greater redundancy.
Be Clear On What Will Be Backed Up
Of all the issues that cause me grief as an installer, I hate the awkward conversations about segregating the switchboard into essential and non-essential loads.
If you buy a cheap system *cough Alpha cough*, it will often have very little surge capacity to start a motor, like the one in your fridge or rainwater pump. In my opinion, one power circuit and some lights are all they’re really good for. I don’t care what the salespeople might have implied; I will not connect your cooktop or air conditioner because it will only end in tears.
Grid Hybrids Are Not Off Grid
An important thing to take from this article is that you must not confuse the terminology with the capability. Most hybrid solar inverters will offer some form of blackout protection in the event of a power cut, but getting through a few hours or a day or two doesn’t mean you can go “off-grid” in a meaningful way. Hybrids aren’t designed to deal with whole house loads and often have warranty exclusions if they’re operated for more than 20% of the time without the grid connected.
You must ensure your expectations are realistic for the budget and documented in the sales process. If you intend to “treat the grid with contempt”, you need a really well-built system. True off-grid energy independence isn’t cheap, but the grid is cheaper and more reliable than the generator you’ll need to have anyway.
You May Need More Solar
Without surplus, cheap energy, batteries don’t make much sense1.
The SolarQuotes Solar Calculator shows you the predicted generation for each month of the year. You can use this to quickly see if you have enough solar to fill your battery in the depths of winter.
For example, a friend with a 13kWh battery still had reasonably large winter bills. He had an 8kW east/west system and wanted to buy a second battery.
In 30 seconds, our calculator showed he can expect 47 kWh per day in January – more than enough for his 20 kWh daytime load plus battery recharge:
But in June, he’s going to struggle to put any energy in the battery at all:
More solar was more important than more batteries in this case.
Nobody has ever complained to me that they installed too much solar, it’s always the opposite.
A big enough solar panel array means that, for any given hour, you can convert whatever sunlight is available into useful energy, especially when the electricity is most valuable at the end of the day. When you have a surplus, the hot water service and/or the electric car charger can be turned on automatically.
Which brings me back to the point. Whether in the long term or a shorter horizon, if you’re thinking about a battery or an EV (a battery with wheels), you generally need surplus solar to charge it cost-effectively.
Batteries Enable More Solar
If you install a solar system with a battery, you can legally install as many panels as the inverter manufacturer allows, which neatly avoids the silly Australian rule limiting systems to 133% oversizing.
Installing 10kW of panels on a 5kW inverter with a DC-coupled battery is not uncommon because you can use any excess power (otherwise clipped at 5kW by the inverter) to charge your battery. This is the fundamental advantage of a hybrid over an AC-coupled battery like the Powerwall.
And That’s Why You Want a Hybrid Inverter
All of this brings me neatly to my final point – that hybrid systems are an excellent option for many, if not most, people.
Batteries aren’t the be-all and end-all. In fact, I have seen a few predictions that once EVs with V2G become common, house batteries will only be bought by homes with special use cases.
If you have legacy solar that works, don’t fret; it doesn’t need to go in the bin if you buy a new hybrid system. A modern hybrid inverter will measure what’s going on, harvest energy from your existing solar (or the grid when electricity is cheap), and offer the ability to offset costs when the price of power triples at 3 pm. Better still, it means you can measure even the dumbest of old inverters.
But the best thing about adding a battery with a hybrid inverter is: it allows you to add more solar.
So what are your options for buying a hybrid inverter battery system?
The answer is you have heaps of options.
A List Of Hybrid Inverters You Can Use As Powerwall Alternatives
This list doesn’t pretend to be comprehensive. With over a thousand units on the CEC-approved list, we can’t cover every permutation. However, every entry on the list is what I see as a more or less viable Powerwall alternative,
Follow the links for a deeper look and some of my thoughts on each option (links will be added over the coming days):
- Selectronic SP Pro (my top pick, robust, reliable, and reassuringly priced)
- Fronius Gen24
- Sungrow SH5.0RS
- GoodWe GW5000D-ES
- GoodWe GW5000-EH
- GE H5.0-1U-10
- Redback SH5000
- SolarEdge
- Q.cells Q.HOME CORE H5
- Growatt MIN 5000 TL-XH
- Sofar HYD-5000-EP-AU
- Huawei SUN2000-5KTL-L1
- Alpha ESS
Summing Up
As a solar installer in Australia, I can confidently say that hybrid inverters are a viable and often superior alternative to all-in-one battery units like the Powerwall. They streamline your solar setup and enable you to legally add more solar panels, allowing for maximum solar generation.
With numerous hybrid inverter options available in the Australian market, choosing a reputable brand, considering your energy import and export data, and consulting a professional installer are essential.
Footnotes
- Dirt-cheap solar sponge tariffs are an exception. In Adelaide, you can pay as low as 9c per kWh for grid electricity during the day if you are prepared to pay 60c per kWh during peak times ↩
About Anthony Bennett
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Hi Anthony,
Thanks for your article. I have 16 x 250w of solar panels (4Kw) on Enphase 215w inverters in the Citipower area in Melbourne. I know I am limited to a maximum 5Kw inverter before export restrictions. I have been looking at Powerwalls for sometime and also have roof capacity for more solar panels. Would I be better going with a hybrid system and can this be done with Enphase Micro inverters?
Hi Cam,
I’m pretty sure you can make use of a 6kW hybrid and leave the legacy enphase system on the grid side of it.
If there’s 4kW of existing system then your new one can be limited to export a maximum of 1 to arrive at a total of 5kW export, however off the top of my head a 6kW Sungrow will handle 12kW of PV solar. Happy days if you have the roof space.
Enphase have a new battery coming, you’ll get first dibs as an existing customer but you’d have to talk to them about compatibility. We suspect it’ll be hard to find enough wall space for the enphase battery system and you’ll not enjoy the same advantages of a DC coupled hybrid.
Thanks Anthony,
Apologies if this is a silly question, but are you saying the solar power from the enphase inverters (which is ac) can feed into the hybrid inverter and then to a battery or the 4kw of solar that I currently have won’t be able to charge a battery in a hybrid setup? Also I have found a few installers I have spoken too still don’t have a great understanding of hybrid inverters, batteries etc. For the Melbourne area how would you go about finding an installer with the right knowledge and expertise?
Hi Cam,
A hybrid can function just like any other AC coupled system, that is you install a consumption meter so that the hybrid can see what’s coming and going from the premises, then give it priorities to work with. If your 4kW enphase system is exporting to the grid, the hybrid will see that and divert the energy into the battery or maybe switch on a load. When the consumption is high and the sun is low, your enphase system will power the house and the hybrid will use it’s own solar capacity and maybe some battery energy to power the house as well.
I wouldn’t expect you can hook up the enphase system to the downstream/backup side of the hybrid as it may not be controlled properly, so if there’s a blackout you’ll lose that 4kW capacity but that’s probably not a deal breaker. If you were to bin the enphase and install a compatible AC solar inverter you may be able to have all your solar available during a power outage, but that would mean an entirely new system and probably sending your old panels to the third world.
Click “I’m ready” and put your details into the SQ website and we’ll find you an installer, or reach out to [email protected]
A great, useful article, but I still don’t understand what a hybrid inverter is. What does it do?
from our glossary:
hybrid inverter : an inverter (see next entry) that has both solar and battery supply, from which it can draw energy to create 230 volt AC power. Hybrid inverters can also draw 240 volt AC from the grid to charge a battery if programmed to do so. This may be triggered by a price signal from an electricity retailer or scheduled for a time of day when grid supplied electricity rates are exceptionally low. With the right electricity retailer and the right hardware, there’s potential for those brave enough to get paid to both charge and discharge a battery.
inverter: These convert direct current (DC) to alternating current (AC). The most common type in Australia are string inverters which send DC produced by solar panels along one or more cables called strings to a single inverter. Another type are microinverters which consist of a small inverter attached to each panel that directly converts its DC to AC.
I’m interested in Vehicle to Home (V2H) or Vehicle to Load (V2L) so my EV can be used to store solar and also to power essential loads in a power outage.
In the schematic I can’t see the Batter (call it EV battery) charge – can this come from a hybrid inverter?
If there is a grid outage (common in rural areas) can my solar be used to charge the EV during the day, and use the EV for essential (V2L) at night. Are there any hybrid inverter/EV combinations that can do this? IF they can I won’t need to install a separate battery
Hi Robert,
There’s nothing off the shelf at the moment but people are doing some experiments.
https://wattever.com.au/power-your-home-from-an-ev/
I’m going off grid by islanding two power circuits in my house and leaving the rest grid connect.
I have five 100ah 48v rack mount batteries and an inverter charger. No drama.
Increased grid connect, I added to myself to cash in.
Over 25kwh of battery backup with inverter that cost me any $12000.. I dont care about the cost but it’s way cheaper and better than retail available systems as I want next to nothing to do with the supply other than then paying me
Location?
That is one of the best-written and well-considered articles on batteries I have ever seen. Well done!
I agree on Selectronic – it’s far and away the most robust and flexible solution and if you want whole house back up, it’s the pick of the bunch. It’s also the only one where you can go fully off-grid if the DNSP is really annoying you and you want to take your bat and ball and go home…
Thanks Tony,
I try to explain to people that spitting the dummy with the grid isn’t the best approach but I certainly see the appeal. Electricians hate network companies too.
Keeping an existing grid connection is cheaper and more reliable than the generator you’ll need otherwise, plus export means you can scrape up a few sheckles to offset the daily cost.
Re. Hot water. I’ve got a SolarEdge system which can be fitted with the diverter to use excess solar. We currently use gas for hot water but want to switch to electric. Any recommendations for an efficient hot water system that plays nicely with solar? Thanks
Hi Andy,
For outright electrical efficiency, where your hot water is produced for 900watts instead of 3.6Kw (ie a system your solar PV is likely to be able to run) I quite like Reclaim CO² heat pumps. Sanden and Stiebel Eltron make a nice unit too I believe. Avoid Dux & Rheem and do not consider Cromagen/Midea.
With that said, I still like the elegant simplicity of a conventional storage hot water with a thermostat and an element. Any electrician or plumber knows how to fix them, there’s no refrigeration mechanic involved and there’s no exclusions to the warranty.
Resistive hot water isn’t as likely to run straight from your solar power, it’s beneficial to use a smaller than normal element (2.4Kw instead of 3.6Kw) but if you have lots of energy to export it can still be a great solution, especially when combined with a dynamic energy diverter such as a greencatch from Catchpower.
Andy,
Any recommendations for an efficient hot water system that plays nicely with solar?”
See my comments at: https://www.solarquotes.com.au/blog/premium-fit-hot-water/#comment-1525470
The Sanden unit’s coefficient of performance (CoP) is 5.96 (at 32.45 ºC ambient air / 18.74 ºC cold water inlet), but I’m reliably informed reduces to around 2.76 (at 0 ºC ambient air temperature).
On 21 Feb 2023, I noticed my Sanden unit had stopped working. The fault was found to be a ruptured replaceable fuse on the secondary circuit board, and it seems an electrical short had probably occurred due to the presence a cockroach, found dead below the board. A replacement fuse was installed, as well as applying a liberal spray of surface insecticide around the internals of the outdoor unit, and the system has been working normally since.
I’ve also experienced an insect infestation in an outdoor immersive electric hot water storage tank system over a decade ago at a property I was renting at the time in the form of an ant nest in the thermostat recess, stopping the thermostat switching on.
When I looked at hot water boiler I found that from heat pumps only Sanden has off-peak allowed in warranty. While obviously cutting power will control any of them, warranty can be voided. DRED would be better but so far no-one seems to bother with offering it. I installed Sanden mid 2021 with tasmotized Shelly 1PM which is controlled by my Home Assistant and viola. No issues since installation except leaking over-pressure valve. Power is delivered depending on PV surplus, weather forecast and current needs. It also does 3-day cycle for legionella, in case it has not been used otherwise. Shelly also logs power usage. There is one caveat, however. Sanden does not start just because it has power. It has to be either – mid-tank sensor below some temp, 24h past last cycle or at 10AM by its internal clock. Potential automation has to accommodate these rules.
There is a problem which makes it impossible. I tried hard when I installed my panels in 2020, however I was simply unable to find any 10kW single phase hybrid inverter! It might be a solution for small systems but as it limits panels power it isn’t true that hybrid makes possible to have more panels. It makes system smaller, limited by inverter size. Unless we speak 3-phase but then it isn’t PW2 alternative which is single phase. On top of these problems I found these hybrid inverters unable to match PW2 inverter output while on battery.
Now, I believe, there is a Delta but not well regarded for this new version (including unreliable warranty). So, even after 3 years still nothing to replace my string inverter.
Hi Darek,
There are a few single phase 10kW units available now. GE offer one with 3 MPPT inputs, I’ll cover that in upcoming posts. The other option is two 5kW units, which gives you 4 MPPT inputs and the ability to split the solar across different buildings. Some manufacturers are even rating their units at 4.999 just to skirt Queensland’s dumb emergency backstop rules. https://www.solarquotes.com.au/blog/qld-dumb-solar-shutdown/
Please stay tuned as we work though the available machines in coming weeks, there certainly are models available now, so long as the stock is in the country.
Anthony, 2x5kW does not fit my purpose:
– It won’t be possible to control export. I have no restrictions but I may need it for Amber
– While I would need PV most during grid failure, I would have only a half of it available.
– It will be poor power rating, let me bet, 3kW from battery?
That 3xMPPT seems interesting, however, for replacing my Goodwe. Especially if it works with high voltage battery (a bit too far for 48V).
You might also like to know that Fronius have promised 8 & 10kW hybrid units, due in “Q3” this year.
Anthony, I’ve got a Sungrow SH10RT, Sungrow SG5.0RT and a Sungrow SBR128 battery connected to 19.92kW of Trina S panels. I also have a 230V AC power source (up to 2.3kW) – that is not the grid – that I would like to use to ‘top up’ the battery in the early hours of the morning, ready for the morning peak demand. Possible? Viable? (For full disclosure, my non-grid power source is 10amp V2L)
Hi Maka,
V2L is a question we’re looking to address in an upcoming post. If it was a Selectronic SpPro I’m pretty sure you could treat it like a generator… but Sungrow are yet to release that functionality.
Where V2L is going to cause problems is with RCD/earth leakage/safety switch functions. Your car will likely see the MEN link in your house switchboard as a fault… I think the only reliable way forward will be to use an isolation transformer and treat the install as you would a boat connected to shore power.
Hi Anthony,
When I was investigating which way to go in late 2021, the default systems (panel arrays and choice of string or micro inverters) were offered up first.
There was an assumption on budget by all quoting installers.
When I asked “what happens if there is a blackout during the day?” I was surprised to learn that I would need batteries.
There are many, many installations without batteries and I think that is a result of installers taking advantage of the rebates.
I said to my installer, it’s like having a bar, a barman, and a willing customer but no beer until the power is restored.
“Oh, you need a hybrid string inverter.”
I don’t like the sound of that; the best of both comes with the worst of both.
But, you should have mentioned this advantage in your article; you can be in blackout and still fully run the house and charge batteries simultaneously.
I chose 40 x REC 370 panels, 2 x Fronius Primo Gen24 5.0 Plus inverters, 2 x BYD HVM 11kWh batteries, 4 x Fronius Smartmeters (set up as 2 independent systems but all 4 strings powering the pool heat pump when grid connected) all controlled by a SwitchDin Droplet.
The system won the Fronius Installation of the Month (Feb 22) because it closely resembled a toy transformer (to me!), still not as neat as a Powerwall, but very pretty all the same.
We were still fine-tuning the configuration, which was mostly achieved in May 22. I still have a monthly account from Ergon, which is negative from Sept to May inclusive.
The system can supply continuous 9kW in backup mode (10% loss due to electrical headroom) and have seen brief output in excess of 11kW, running 6 x reverse cycle A/C’s on top of normal 0.6kW house load with bore pump and water urn cycling in/out.
40 sec from blackout to backup.
BUT and a biiiig BUT, Fronius refuse to alter the b/u frequency from 53Hz, citing not wanting to sync with another grid-connected inverter. My coffee machine and pool filter do not like it at all.
FIX IT FRONIUS!!!!!
Anthony
I want to ask how you tested and came up with your recommended list?
Like Monty’s reply i worry about 53hz of some of these inverters in your list – why was it not part of your criteria as it is extremely important as a lot of devices cannot survive for any period at that frequency
By the way – I agree with your #1 choice – i have 2 7500 watt Selectronics
Hi Tim,
The list wasn’t a scientific endeavour but it’s a range of what’s available. I suspect there could be more added as new entrants appear. Some of them I wouldn’t recommend but like the Delta unit in our last AC coupled comparison article, there has to be something to provide contrast.
Hi Monty,
Sounds like a good fun system you have there.
We have a new post out that might be of interest to you. Right now your Fronius Gen 24 isn’t compatible but I’m led to believe they’re being developed for coupling to a Selectronic SpPro.
I won’t predict when or if all of your equipment would play nicely, but if you want to treat mains electricity with contempt then there’s no substitute for a proper grid forming inverter.
https://www.solarquotes.com.au/blog/selectronic-sp-pro/
Anthony,
I have tested and supplied feedback to Fronius, including a request to have their Premium Software display Frequency, a currently unavailable channel, surprisingly.
This has given me a little more faith in their product and service. It is a shame I had to endure repeated “cannot be done” replies from many and varied sales engineers.
General question about using a house battery. I have a 13kwh battery (hybrid), 12kw of solar and an EV. My house is very energy efficient and typically overnight the battery still has 4-5kwh left by the morning. This will change over the next 12 months as we convert gas appliances to electricity but for now I have excess storage.
I can use some of this to charge my car overnight, but should I use the house battery in this way? I can schedule EV charging for a few hours and use 2-3kwh.
thanks
George – missing data is how much power do you punch up the grid.
You sure can use your batteries this way but does not make sense unless your house batteries at least are equal in size (best to be greater) than that of your car
Lots of other things to consider but that’s a starting point
Hi George,
Thanks for electrifying, I’m just back from the Smart Energy Expo in Sydney and the take home message is this : Just hurry up and get on with it.
Using batteries to charge batteries rubs me up the wrong way a bit. Having read a lot of warranty documents I would think the better option is not to hammer your house battery so much, thereby extending it’s life.
See how you go as the gas appliances disappear.
Cheers
Hi Anthony, thanks for the explanation. We are looking to replace our 1.9kW solar with a larger system. We are in Perth so are sadly limited to a 5kW inverter on single phase. (I don’t know what Western Power has against the concept of export limiting a larger inverter) We’ve recently bought an EV and are weighing up whether it’s worth the extra costs of getting a hybrid inverter and small battery to allow stepping up above the standard install of a 6.6kW panel ‘limit’.
Can you tell me – am I correct in saying that a, say, 9kW hybrid inverter in this situation would have a 5kW AC side (complying with Western Powers Rule) and a 4kW DC side?
Also, can the 4kW DC side only send power to a home battery? Given that I have a 78kWhr mobile battery (EV) it would be great if the inverter could send excess to it independent of the 5kW AC limit. (This EV can accept 7.3kW). Thanks for any enlightenment.
Regards, Mike.
Hi Mike,
In the coming days we’ll have more posts about more hybrids, but for an example you could get a nominal 4999w Sungrow and hang two strings of 13 x 460w panels on it for a total of 11.69kW peak solar capacity. That will run 5kW into the grid and leave more to charge the battery simultaneously, however I couldn’t tell you exactly how much, there’s a maximum 6.6kW rating and it would also depend on the battery size & state of charge.
Car charging will be via the AC side, so a hybrid will peak at 5kW continuous throughput, wherever you decide to prioritise the energy flow.
Western power will allow a separate battery inverter and a solar inverter so you could also explore a Selectronic SpPro combination as well. ie There would be an export limit on the total system, but 5kW AC output from a solar inverter, plus 5kW AC output from a battery inverter (which is powered from a virtually unlimited size DC coupled solar array) would satisfy your car charger and house too I would think? Would need to clarify with a local installer anyway.
I have 2 x 3 phase systems (8.1/8.2 west & 6.6/5 east) on Fronius Symo inverters. No monitoring hardware at this stage but working from home and no gas means we are able to harness high production periods most of the time through positive solar habits. Washing machine/dryer & dishwasher generally run in the middle of the day. My issues are cooking (induction) and heating (ducted heat pump) at peak times as the sun goes down.
Off the cuff, what would you recommend? What should I research? DC coupled battery? Ours bills are reasonable but would like to eliminate if possible (for green & $$$).
Many thanks,
Drew
Hi Drew,
That’s a mildly tricky one and it’ll depend on connection capacities and budget.
Going to first principals you could try a device like the sadly defunct Solectair which is a passive solar heating device to reduce loads on your air con.
If you want the gold standard you could have your Fronius units SCERTified and install three Selectronic SpPros, but we might spend $50k on that venture, or more? You could treat the grid with contempt though…
https://www.solarquotes.com.au/blog/selectronic-sp-pro/
Depending on the size of your existing inverters, there may be connection capacity left to enable you to add another Fronius Gen24 (or swap out an existing unit?) and that is a really nice hybrid solution.
https://www.solarquotes.com.au/blog/fronius-gen24-review/
Cheaper again would be a 3 phase Sungrow, but I’m not sure they would tie the monitoring together as well, though there may be some chance of running one of the Fronius units on the backup side of the hybrid for better capacity when the sun is shining?
More details will help
Cheers
Would a DC-coupled system be worth considering? I’m still researching, I hope that isn’t a silly question.
Drew if you have a look at these posts it might help, but ask any questions you need
Cheers :
https://www.solarquotes.com.au/blog/selectronic-sp-pro/
There are low voltage Sungrow units available as well as others.
https://www.solarquotes.com.au/blog/solar-switchboard-upgrade-guide/
Drew – if you are just trying to time shift to beat Peak rates etc when cooking – then have a look at the Goodwe SBP Pro – AC coupled for about $1500 – will output 5KW and can accept 48V batteries so relatively cheap to add
It is a single phase unit – but can be coupled with a Goodwe GM3000 – three phase meter to net out all your phases.
Will not maybe satisfy both your AC and Induction cooktop at once – but there is some trickery that can be done with having multiple units on different phases – but you then get into some custom control logic (i have 3 of them on 3 phases and can store/export 15KW)
Hi Anthony (and the SolarQuotes team),
We’re looking at upgrading our Solaredge inverter (SE6000H) under their program to swap it to a hybrid for free to a 10kw inverter and the SolarEdge battery. We’ve currently got 7.4kw of panels and one installer suggested only going to 133% of panels and not 200% because it’s “not efficient” once the battery is charged.
I kind of understand their point but I’m thinking why not go all the way to 20kw and have solid generation early morning/ late afternoon/ winter etc. as well as the potential for a second battery in the future or charging an inevitable EV?
Am I wasting money adding the extra 7 odd kw to get to 20kw (I’ll be export limited by Essential Energy to 5kw btw).