I've installed a home battery

[p38arover]

I did some spreadsheet calculations and I think the new 13.4kWh battery connected to my solar panels may pay for itself - eventually. It cost $10,640 to upgrade my solar system to the battery.

If electricity prices continue to rise (despite the gummint's promise of cheaper electrickery), the return on investment may be even better/quicker.

I'll continue to update my spreadsheet to convince myself that I did the right thing. I haven't yet decided whether to change my electricity plan to TOU (Time of Use). Various sites suggest TOU will give a quicker payback.

In July 2022, the supply rate went from 27.6 ¢/kWh to 36.762 ¢/kWh -a 9.162 ¢/kWh or 33.2% increase. (Prices shown include GST.)

In July 2023, the supply rate went from 36.762 ¢/kWh to 46.552 ¢/kWh - a 9.79 ¢/kWh increase, i.e., 26%.

We now get a paltry 5 ¢/kWh for exported power and some suppliers are proposing that we will have to pay them 1.2 ¢/kWh to export between 10am-3pm. When we first installed solar, we were getting 68 ¢/kWh for exported power so our first system (we now have two) paid for itself within 2 years.

What's going to happen this year?


We use a lot of power with the ducted air con. Even the standing power use is around 500 watts. It's amazing how much power is used by multiple computers, three NAS boxes, large TVs, and devices switched off but on standby, etc. Most lights in the house are LEDs. My wife was in hospital last week so I turned off a lot of stuff. That dropped the standing consumption to around 250 watts.

I used to track my solar generation and power consumption on PVOutput but owing to technical reasons, that stopped back in 2019. I've now restarted tracking. This is my PVOutput page: p38arover 6.460kW (https://pvoutput.org/list.jsp?userid=309) The graph doesn't take into account what is fed into the battery nor what is drawn from the battery.

I will keep you advised how it goes. The wet weather isn't helping this weekend! :)

[Arapiles]

Our premium FIT ends this November and after that we'd be lucky to get 5c/kwh - our plan is to increase the number of panels we have, put a battery in and start load-shifting so we're not paying for premium rates in the evening.

[DieselDan]

I've got 12kW solar panels and a 13.5kW battery that I got installed last year.
The leccy provider only gives me 5c/kWh for what I export and charges me higher supply rates between 3pm and 9pm so it's a case of shifting usage and hoping that the battery is fully charged by 3pm so that it covers the high cost period.
It worked really well over summer and the system is still creating significant solar energy at 6pm so between the solar and the battery I never used any peak priced electricity and even made a profit!
In winter, the solar is done and dusted by 4pm, but unless the weather has been really bad, the battery is still fully charged, so it's working out so far.

[DieselDan]

Forgot to add, the standing consumption usually hovers around 0.2 - 0.3kW, which is mostly the fridge, a couple of computers, a few LED lights and the septic pump.
Using the battery app is interesting to watch the different consumption levels of various items as they are turned on!

[p38arover]

I just received my latest electricity bill. For the month, I made a whopping 48 cents from power exported to the grid.

EDIT: Sorry, we made 48 cents, not 37. Updated post

[goingbush]

I've figured out a way to use the 28kwh battery in my E-Landy as a house battery .

Charge on off peak at 8c kwh (midnight to 6am) or for free from 11AM to 2PM then plug in to draw on the battery and feed in to the house at peak evening loads 2PM to mifnight . (peak is 33c on my plan)

I can feed in 1kwh or 3kwh depending which inverter I plug into . Just using second hand solar inverters ,( they don't care if the incoming DC feed is from solar or from a battery ) disadvantage over a proper battery system is I need to manage it manually .

190637 190638

[V8Ian]

I just received my latest electricity bill. For the month, I made a whopping 48 cents from power exported to the grid.
You could retire on that, Ron. [biggrin]

[Graeme]

How much did you pay for feed from the grid?

[p38arover]

How much did you pay for feed from the grid?

I'm with AGL, their charge is 42.32 c/kWh + GST = 46.552 c/kWh. I'm not on Demand nor TOU rates.

I'm going to seek a better/cheaper rate. AGL don't tell you on their website just what their rates are.

I haven't worked out if it's worth changing to a supplier who gives free power between 11am-3pm. I could use that during winter to charge the solar battery. In summer, that probably won't be necessary as we generate plenty of power then. For example, Oct 2023 - May 2024 we exported 3MWh (before battery installation). For the year Jun 2023 - Jun 2024, we bought in 6MWh after exporting 4.7MWh. I don't know how much of our own power we consumed. The new software that came with the battery installation will give us a better idea of that.

[Graeme]

Thanks Ron. I suppose really I was wondering how much less your grid power is now costing you.
My OE TOU peak rate is 49.7c and my average is 36.4c not including feed-in but the rates would be lower with 5c FIT instead of the 10c FIT on this plan.

[4bee]

I did some spreadsheet calculations and I think the new 13.4kWh battery connected to my solar panels may pay for itself - eventually. It cost $10,640 to upgrade my solar system to the battery.

If electricity prices continue to rise (despite the gummint's promise of cheaper electrickery), the return on investment may be even better/quicker.

I'll continue to update my spreadsheet to convince myself that I did the right thing. I haven't yet decided whether to change my electricity plan to TOU (Time of Use). Various sites suggest TOU will give a quicker payback.

In July 2022, the supply rate went from 27.6 ¢/kWh to 36.762 ¢/kWh -a 9.162 ¢/kWh or 33.2% increase. (Prices shown include GST.)

In July 2023, the supply rate went from 36.762 ¢/kWh to 46.552 ¢/kWh - a 9.79 ¢/kWh increase, i.e., 26%.

We now get a paltry 5 ¢/kWh for exported power and some suppliers are proposing that we will have to pay them 1.2 ¢/kWh to export between 10am-3pm. When we first installed solar, we were getting 68 ¢/kWh for exported power so our first system (we now have two) paid for itself within 2 years.

What's going to happen this year?


We use a lot of power with the ducted air con. Even the standing power use is around 500 watts. It's amazing how much power is used by multiple computers, three NAS boxes, large TVs, and devices switched off but on standby, etc. Most lights in the house are LEDs. My wife was in hospital last week so I turned off a lot of stuff. That dropped the standing consumption to around 250 watts.

I used to track my solar generation and power consumption on PVOutput but owing to technical reasons, that stopped back in 2019. I've now restarted tracking. This is my PVOutput page: p38arover 6.460kW (https://pvoutput.org/list.jsp?userid=309) The graph doesn't take into account what is fed into the battery nor what is drawn from the battery.

I will keep you advised how it goes. The wet weather isn't helping this weekend! :) Ron, just because they are not switched on doesn't meqn the Crankcase heaters are still off, Mine is an 80 watt heater. & on all the time, some cqn be activated by the Comp contactor & others not. This is essential for Cold Weather starts otherwise you could finish up with a shagged donk. This only applies to Recip compressors later one are different.

[disco gazza]

Am starting to think a battery would be good for my solar system as the rate of feed-in is getting lower down here in Tassie.
So what brand of battery did you get Ron?
If anyone else has a battery set-up, what battery did you get.
TIA.

DG

[p38arover]

I’ve got an AlphaESS 13.34kWh system. I bought it through Green.com.au (https://www.green.com.au/) (The family name is Green, it’s not just a name to appear green.)

It’s fed by my existing two solar systems.

The monitoring software appears very good. I haven’t worked out how to actively upload it to PVOutput so I download the data from the battery/inverter and manually upload it once or twice a day.

See p38arover 6.460kW (https://pvoutput.org/list.jsp?userid=309)

[oka374]

We've had a 14kw Tesla Powerwall 2 for nearly three years now, "bought" when a great NSW govt subsidy was running back then.
Could do with more solar in winter as we heat with a/c and only have a 5kw system so have been using lots of grid power once the battery is depleted of a night.
Had over $300 credit at the start of winter so not really worried about the cost as it's still far cheaper than timber for the slow combustion heater.

[p38arover]

I just received my latest electricity bill. For the month, I made a whopping 48 cents from power exported to the grid.

I've just had a look at some past bills (I have them in a spreadsheet).

These are the amounts we received in credits over several quarters:
$758.20
$529.04
$571.88
$331.16
$679.80
$538.20
$378.60
$501.80

Our first 3.4kW solar system cost $10K and was paid for very quickly.

The next quarter the feed in tariff dropped to 7 cents so we got $22.

I wouldn't install a solar system today without a battery.

[DieselDan]

I've also got a Powerwall 2.
And just today I received notification that my feed-in tariff is going down to 4.5cent per kW/h so I'm glad I've got the battery as solar wouldn't really be worth it on its own.

[Tombie]

I've just had a look at some past bills (I have them in a spreadsheet).

These are the amounts we received in credits over several quarters:
$758.20
$529.04
$571.88
$331.16
$679.80
$538.20
$378.60
$501.80

Our first 3.4kW solar system cost $10K and was paid for very quickly.

The next quarter the feed in tariff dropped to 7 cents so we got $22.

I wouldn't install a solar system today without a battery.

Save me the effort, as you have all the data.... How long to pay off the battery?

When I did the sums, I'd pay off the battery - just as the thing basically hit EOL. So saved nothing - all I got was some black out security.

[DoubleChevron]

Save me the effort, as you have all the data.... How long to pay off the battery?

When I did the sums, I'd pay off the battery - just as the thing basically hit EOL. So saved nothing - all I got was some black out security.

It probably works out well if you have the existing solar infrastructure and use a lot of power. I'm far convinced when it comes to batteries for the majority. for starters what do we do with them all at EOL. And I'm not wililng to have the fire risk here myself :)

[prelude]

the gubberment down here will kill all subsidies beginning 2027. This means that during peak hour (when everybody's solar is working just fine) you will be paying to enter the grid (already happens here and there) etc etc.

Mate recently bought a new property with 50kw of solar pre installed. Badly I might add but nothing we can't sort out. He is also eyeballing batteries but I have found it to be a difficult journey thus far. Such a large battery bank in lithium you do NOT want in or around your house IMHO so we are looking to install those in a small container outside of the building. Will add a small AC to manage temperatures in there to keep them batteries happy :) Still. Your average lithium battery manufacteror will give you around 2000 cycles at around 80% DOD. If I were to go with the "between 20% and 80%" crew, which I currently do with my mobile devices, I wonder why I wouldn't simply get myself some proper lead acid. I mean, the weight and size is not a problem and they are 4 times cheaper, even if they don't last as long AND I can store them inside the building.

Having said that, sticking to lithium since he thinks that's hip :) He wants to go totally off grid or at most reduce his connection to the smallest we can get here so that he would be able to charge his battery bank if solar proves to be insufficient. With so much solar on the roof he should be fine getting a battery bank charged, even during winter but you need the inverters to provide the power that you use. Sizing for an airconditioning is doable but he also wants to use his spot welder which is a beast of a machine with very large peak currents. I am kinda doubtfull we can make that work. It's probably possible but that would require a very large oversized inverter (or bank) and I think the costs for this would be excessive.

In short, I wonder what the ROI would be in this particular case. I guess power prices won't be going down untill we roll out more nuclear (fission or fusion, if ever) so it will be interesting to watch this space.

Cheers,
-P

[DiscoDB]

Save me the effort, as you have all the data.... How long to pay off the battery?

When I did the sums, I'd pay off the battery - just as the thing basically hit EOL. So saved nothing - all I got was some black out security.

The problem with the payback period is house solar storage batteries are truly overpriced on a $/kWhr basis. They seem to sell for 3-4 times the equivalent cost of a replacement EV battery which internally use the same cell technology and battery packs.

Hopefully as more EV/PHEVs are able to offer V2G this will help drive residential house batteries down in price as well.

[Graeme]

My annual grid power cost is currently $1,200 so there's no case for a battery on saved power costs.

[DieselDan]

The only utility I have (apart from water into the property) is electricity and the annual bill was well over $3k.
The pay off time for my entire solar/battery system is within (just!) the warranty period of the battery, so I figured it was worth doing.
The power outage backup protection has already been used several times and, should I ever sell, the theoretical increased value to the property far outweighs the amount I spent installing it.

[Graeme]

I'll buy a small generator to cover outages once my change-over switch and inlet socket are installed at the house, which may have to wait until my licenced brother makes his usual after-Christmas visit. I'm sure that the farm needs a portable generator.

[DiscoDB]

I built my own home back up system using 12v Lithium Batteries and a UPS Inverter. Keeps the main fridge, a small freezer and some LED lighting running for 2-3 days and automatically switches from AC to DC and back as required.

For around $2,500 gives me 6.9kWhr of back-up capacity.

[p38arover]

Electricity suppliers aren't your friend.

I've been with AGL for quite some time and their tariff has been (including tax) 46.55 c/kWh and the feed-in tariff has been 5c/kWh. Daily connection fee of $1.084

I did a Compare the Market and found their best plan was also AGL but with a tariff (incl tax) of 33.674 c/kWh and a FIT of 7c/kWh with a daily connection fee of 90.93 cents.

AGL never told me they had a better and cheaper plan. I've since changed to the new plan.

Mongrels.

So far, it's looking that with the battery, my electricity costs for the month are close to half what they were last month (we are on a monthly billing cycle).

[p38arover]

We are finally getting some full sun and, on some days, the battery is getting a full charge. Because it's warmer, we can turn the air con off earlier (heating in the morning) and turn it on later in the evening (again heating).

Over the past week, our consumption from the grid has been (actual consumption including from battery in brackets):

Sat: 3.56kWh (26.24kWh)
Sun: 12.56kWh (28.87kWh)
Mon: 9.42kwH (27.13 kWh)
Tue: 11.02kWh (25.33kWh)
Wed: 2.11 kWh (19.04kWh)
Thu: 1.55kWh (18.39kWh)
Fri: 3.93 kWh (17.06kWh) - Today so far to 4pm.

You can see the days when it was warmer and getting enough sun to fully charge. At the moment, the battery is fully charged and we aren't drawing any power from the grid, we are running on solar generation and battery. Our load is currently (no pun intended) is 343 watts, 15 watts of which s from the battery. The rest of our solar power is going to the grid and topping up the battery.

191067

[flob241981]

same

[NavyDiver]

Home battery was not on my To Do list. Getting interested in a company I bought and SOLD years ago that may make Solid State ones at scale soon- Its always Soon of course [bigrolf]

Putting Solar on my new shed being build in a few weeks. Several quotes and one just blew me away!

"[B]15 x 440W Canadian Hiku 6 Split Cell Mono Black Tier 1 panels
+
1 x 6 kw Potis Edge 1Phase Hybrid smart WI-Fi inverter + 1 x 20 kW Potis Edge Battery unit
"
$5490 inc GST[tonguewink][tonguewink][tonguewink]

Several other quotes with out hybrid or the stay on when the grid goes off are more by $$$$$$$

The fact I happily paid for 2 10kWh flow batteries years ago for about $20,000 or 10k each has this in prospective. Noting RFX is dead now. I have a funny thing with creditors claim on the liquidation as both of them required another replacement under warranty Redflow kindly gave me each time they replace those two
[bigrolf][bigrolf][bigrolf][bigrolf][bigrolf][bigrolf][bigrolf]

Not sure if I will ever see money for that. RIP another Aussie try hard


Back to my unexpected home battery. Canadian solar is not a fly by night company. About us | PotisEdge (https://potisedge.com/about/) are Canadian as well.

Both are built in China I assume!

Making a little addition to the rear of my shed now for 20kWh battery I did not expect to be getting [biggrin][biggrin][biggrin]

[PhilipA]

I have been pondering what to do in the future if the suppliers fit TOD meters to my villa's electricity supply . I cannot fit solar panels or get the battery subsidized. I live in a retirement village where I lease the house on a lifetime lease. I could theoretically buy solar panels but my roof area is small and poorly oriented and no subsidies.

I am considering making my own battery set up where I time it for off peak charging early in the morning for use in peak times. I thought of maybe 4to6x300amp hour LifePo4 12v batteries and an inverter

It would have to be pretty cheap as I am eligible for NSW State subsidies and currently the Commonwealth subsidy so my total yearly electricity cost is less than $1000.
Regards PhilipA

[p38arover]

Philip, there are electricity plans which offer free electricity at certain times of the day. The battery controller can be set up to use that.

However, power might be expensive at other times.

[austastar]

Hi,
If half your bill is hot water, switching that to off peak will save a bit and use the battery for the rest of the house during peak tariffs, recharging from off peak.
The cost and times of each tariff will determine whether you win or lose.
Cheers

[PhilipA]

My hot water is by instantaneous gas which ironically needs power to activate the start up. I have bought an inverter and have a few 12v batteries in case we have a blackout. I have a 40AH AGM and a 100AH and 120AH Lifepo4 in my car and caravan. This will also be enough to run my fridge for a few days.
Seeing the Spanish and Portuguese managed to get back on line in 12 hours our network should be able to be back up in 24hours (sarc) . I was in Porto when it happened.
Regards PhilipA

[NavyDiver]

I have been pondering what to do in the future if the suppliers fit TOD meters to my villa's electricity supply . I cannot fit solar panels or get the battery subsidized. I live in a retirement village where I lease the house on a lifetime lease. I could theoretically buy solar panels but my roof area is small and poorly oriented and no subsidies.

I am considering making my own battery set up where I time it for off peak charging early in the morning for use in peak times. I thought of maybe 4to6x300amp hour LifePo4 12v batteries and an inverter

It would have to be pretty cheap as I am eligible for NSW State subsidies and currently the Commonwealth subsidy so my total yearly electricity cost is less than $1000.
Regards PhilipA

It's tricky for many people Phillip. Units and flats and high-density places may not be suitable or economical for solar/batteries or similar. A person I know has a house heavily shaded by a Mountain to their North.

The real problem for everyone is the retail and commercial prices and the greenwashing of some wish list Types shout loudly. I can be included on BOTH sides of a fence on that divisive topic


The [B]almost rude part is I may use a commercial wholesale provider who may pay me rude amounts when wholesale prices go nuts which they do at times. That provider is not the Green or Red in the traffic lights.

Some are setting up a VPP. If your very lucky to be in one of the few areas that exists you may be able to have Spare Solar from people in the VPP.

Virtual Power Plant (VPP) Comparison Table - SolarQuotes (https://www.solarquotes.com.au/battery-storage/vpp-comparison/)


I am not in a VPP area. I did look and consider stumping up about a million to set one up locally then recalled managing a medical centre for a few decades and regained my sanity [bigwhistle][bigwhistle]

Of interest to some may be a report that a 6Kwh home system may provide 15 to 10 kWh of power per day in Winter in Meccico (VIC) and 20 to 25 kwh or so in Summer. RACV linked me to that data.
July power here including EV charging, HEATING, cooking and hot water was "01/07/2025 - 31/07/2025 1,291.01 kWh @$0.2700" Plus supply charges

I think even paying for my EV is cheaper than my Disco $400 (+ Maintenace per month) I do miss it!

Roughly 1/2 my winter power might be covered if the sun shines a bit. If I do that checky Amber wholesale bit payback time for the cost of the system is still a few years! It's not free and clearly not everyone can do it. I honestly think the whole country, Industry and others even need a better option. Happily I recall my former line "recalled managing a medical centre for a few decades and regained my sanity" [bigrolf][bigrolf][bigrolf]

Have a great weekend all. A few items cooling in the fridge for a post run rehydration. I drink H20 for the real rehydration.[bigwhistle][bigwhistle]

[p38arover]

My battery upgrade was done yesterday. It has gone from 13.34 to 26.68 kWh capacity. Now I just need some sun.

The additional battery was funded largely by the govt. subsidy. Cost was $8,000 less subsidy so out of pocket was $3,412