Solar Panel, Power & Battery Discussion

[NM]

Last year my highest consumption month was double that of the lowest consumption month

Overall winter 3 J/J/A is 50% greater than summer D/J/F

In SEQ, my consumption is significantly higher in summer (Air-Con is biggest consumer), but also aligns with highest generation period. So my excess solar is very low in summer. I find Autumn and Spring are the seasons with my highest excess generation, due to longer hours of generation and minimal AC usage. Winter generally has more excess generation that summer for me.

The only way battery makes sense for me is if I add more generation capacity, which I can only do if installing a battery. This is due to restrictions on system sizes imposed by Energex. So my costs for battery install need to include new panels installed, re-stringing my existing panels, as well as the battery itself.

If basing it on purely on current tariff rates, its very marginal for me. But if I include an assumption (reasonable I think) that tariffs will continue to increase and are nowhere near a stable/peak cost, then over a 10 year period I will be significantly better off. And beyond 10 years, hopefully it will just be a battery replacement cost as panels all have 25 year expected service life (likely more than my personal service life in this property).

 

[Quickstatus]

tariffs will continue to increase

Here is the problem

The official position for the net zero is that electricity prices will go down over time
Im struggling to reconcile that with the notion of batteries which necessarily assumes that prices will stay the same or go up.

 

[NM]

Here is the problem

The official position for the net zero is that electricity prices will go down over time
Im struggling to reconcile that with the notion of batteries which necessarily assumes that prices will stay the same or go up.

My personal opinion is that the official position is flawed and will not reflect reality *

* using terminology appropriate for posting on AFF

 

[AuSammy]

Most of the alleged x-spurt talking heads on the tellie say that renewables are the cheaper option for the nation to get off burning stuff in the longer term but to get there tariffs will go up in the short to medium term until we get over the hump of converting.

On that basis I am assuming tariffs won't improve and will probably get worse over at least the next 5 years.

 

[exceladdict]

Those gosh darn unknowns impacting our financial models yet again The whole exercise has shown me that the headlines ("this will save households $1000 per year!") are never perfectly accurate, and not to trust the broad claims, especially from people trying to sell you something.

Last year my highest consumption month was double that of the lowest consumption month

Overall winter 3 J/J/A is 50% greater than summer D/J/F

Thanks for sharing this - it will be very interesting to see the winter data when we capture it.

 

[RB]

Those gosh darn unknowns impacting our financial models yet again The whole exercise has shown me that the headlines ("this will save households $1000 per year!") are never perfectly accurate, and not to trust the broad claims, especially from people trying to sell you something.


Thanks for sharing this - it will be very interesting to see the winter data when we capture it.

If you are really keen you could join pvoutput.org & find similar size systems in your postcode & have a look at some of their stats.
We have 6yrs of stats with the fronius smart meter so that helps but some years get skewed by holidays, particularly when when have gone on long holidays in winter. The noreasters do most of our summer cooling so very little air con used in summer

 

[Quickstatus]

I purchased a thermal detector. Handheld and image appears on mobile phone

I'm going to use it to check the cold spots to see if I can improve heat loss in winter

FLIR one edge Pro

 

[kookaburra75]

Last year my highest consumption month was double that of the lowest consumption month

Overall winter 3 J/J/A is 50% greater than summer D/J/F

We're in Canberra, where winter is the heavy-use period for us. I've been tracking the stats since our system was installed 8kW of panels - who doesn't like a good spreadsheet. The consumption during winter is 4x higher than summer. We don't have central heating/cooling and rely on electric panel heaters and the ceiling fans in reverse during winter. We only dip into the red in terms of credits on our bills in the winter quarter, which has been $550 on average.

Date	Yield of Plant(kWh)	Feed-in Energy(kWh)	Purchased Energy(kWh)	Household Consumption (kWh)
2022-07	482.3	367.8	928.4	1042.9
2022-08	602.6	405.8	827.6	1024.4
2022-09	921.5	602.2	600.8	920.1
2022-10	982.3	808.6	307.9	481.6
2022-11	1255.6	1063.9	137.3	329.0
2022-12	1411.6	1233.9	100.3	278.0
2023-01	1286.2	1139.3	78	224.9
2023-02	1160.6	1062.4	82	180.2
2023-03	988.8	868.6	85.3	205.5
2023-04	716.7	596.9	344.9	464.7
2023-05	567.9	291.1	993.7	1270.5
2023-06	421	146.9	999.9	1274.0
2023-07	569.4	321.3	756.8	1004.9
2023-08	684.3	404.1	708.5	988.7
2023-09	1061.5	855.4	354.4	560.5
2023-10	1160.3	1011.1	160.3	309.5
2023-11	1099.2	937.8	114	275.4
2023-12	1232.9	1081.6	89.5	240.8
2024-01	1194.3	1041	85.6	238.9
2024-02	1075.9	922.5	89	242.4
2024-03	1027.4	884.6	109.1	251.9
2024-04	699.5	553.6	230.4	376.3
2024-05	566.4	297.4	625.8	894.8
2024-06	462.3	192.5	861.7	1131.5
2024-07	556.9	217.6	1086.1	1425.4
2024-08	753	516.4	584.5	821.1
2024-09	1042.6	697.1	471.5	817.0
2024-10	1106.1	885.4	251.3	472.0
2024-11	1072.8	921.6	89.7	240.9
2024-12	1494.4	1306.4	93.6	281.6
2025-01	1364.4	1155.9	93.6	302.1
2025-02	1147.5	961.8	88.7	274.4
2025-03	992.9	837.7	109.2	264.4
2025-04	770.6	600.3	136.9	307.2

 

[Jacques Vert]

We changed to Amber a couple of months ago. With Amber you buy and sell at wholesale prices. (You still have the access charges plus $22 per month to Amber.)

It's rained here in CFS for most of the past 5 weeks and our daily usage has been less than $2 either way.

FInally the rain has stopped and we've had price spikes for the past few days as the weather has gotten colder. Yesterday our net earnings were over $111. Previous day was >$34.

If anyone would like a referral, check my post here: Amber Electric

 

[NM]

I have temporarily put my battery purchase/installation on hold, pending making a decision about potential change to my pool heating solution. My current pool heating is a solar solution consisting of heat absorbing piping/tubing on the roof. While it is on the south-facing roof, the circular cross-section of the pipes/tubes does not reduce its efficiency for heating from the sun. It is about 5 years into an expected 10 years life.

So I am considering removing the piping/tubing on the south-facing roof and installing around 10kW of new panels on tilt frames to provide a significant increase over the current 6.6kW north-facing panels to feed into battery/inverter (Tesla PW3 can take up to 20kW panels), then install a Heat Pump for pool heating.

This option will increase my overall cost by around $7K (remove old solar heating, paint roof section, install new pool heat pump), but the additional panels will more than cover the energy required to run the electric heat pump and ensure battery is fully charged before each evening peak tariff window.

Cost consider is that the current pool solar will require renewal or significant maintenance cost in about 5 years time, and a good quality heat pump for pool should last 15-20 years with minimal maintenance. So I am really just bringing forward costs that otherwise be needed in the future.

Still considering the options. I don't want to get caught by any future changes to the battery rebate scheme, such as only applying if you sign up for a VPP contract (which I do not want), and I am anticipating energy costs are going to continue to increase at crazy rates. Its not just a pure numbers game for me, since it is impossible to accurately predict future costs and basing calculations on current costs is definitely not going to accurate. The important thing to me is ensuring that I am able to control how I use the energy I generate or purchase, and reduce my reliance on purchasing from the grid.

Hopefully will be able to make a decision soon.

 

[SeatBackForward]

This option will increase my overall cost by around $7K (remove old solar heating, paint roof section, install new pool heat pump), but the additional panels will more than cover the energy required to run the electric heat pump and ensure battery is fully charged before each evening peak tariff window.

Cost consider is that the current pool solar will require renewal or significant maintenance cost in about 5 years time, and a good quality heat pump for pool should last 15-20 years with minimal maintenance. So I am really just bringing forward costs that otherwise be needed in the future.

We've recently had a new fibreglass pool with heating and solar all installed in the last six months. One thing that seems to have worked very well for us was using a Solar Blanket on the pool - Heat the pool during the day when the sun is shining, and the cover means very minimal heat loss over night.

Over the Easter Weekend on the Thursday the pool temp was about 21º, but using the heater during the day and the blanket overnight, by Saturday morning it was up at 28º.

 

[NM]

We've recently had a new fibreglass pool with heating and solar all installed in the last six months. One thing that seems to have worked very well for us was using a Solar Blanket on the pool - Heat the pool during the day when the sun is shining, and the cover means very minimal heat loss over night.

Over the Easter Weekend on the Thursday the pool temp was about 21º, but using the heater during the day and the blanket overnight, by Saturday morning it was up at 28º.

Unfortunately, the shape of our pool provides significant challenges to the installation of a pool blanket. For us, it would need to be an automated process to cover and uncover the pool, otherwise the pool blanket would just function as a leaf catcher all year round.

 

[Quickstatus]

We changed to Amber a couple of months ago

Had 2 colleagues that were with Amber.
No longer because their overall electricity costs were much higher. One now with AGL the other with OVO

They were taken by screenshots showing the resident making money but when they compared the total cost on an annual average cents/kWh they were worse off.

They had Batteries/solar/EV

 

[Jacques Vert]

Had 2 colleagues that were with Amber.
No longer because their overall electricity costs were much higher. One now with AGL the other with OVO

They were taken by screenshots showing the resident making money but when they compared the total cost on an annual average cents/kWh they were worse off.

They had Batteries/solar/EV

That's interesting. We have solar & battery, no EV. So far seems to be working in our favour although we do aggressively manually control when we buy and sell, especially during price spikes.

It will be interesting to see what our first bill looks like.

 

[DejaBrew]

Had 2 colleagues that were with Amber.
No longer because their overall electricity costs were much higher. One now with AGL the other with OVO

Amber strikes me very much as one of those "horses for courses" offerings. No doubt some households will do very well with it, whilst others will fare poorly. Not declaring that they're good or bad, just a matter of YMMV.

 

[RB]

Unfortunately, the shape of our pool provides significant challenges to the installation of a pool blanket. For us, it would need to be an automated process to cover and uncover the pool, otherwise the pool blanket would just function as a leaf catcher all year round.

Maybe this product is worth some research. We have a spa but they advised I could also use it Water TechniX Liquid Blanket 1L

 

[Quickstatus]

horses for courses" offerings.

Yes I think buyer beware because screenshots just show the good bits. Need to look at a whole year and compare.

 

[Quickstatus]

It will be interesting to see what our first bill looks like.

It's the overall annual cents/kWh that counted
Remember that it is more difficult to use the battery for dual purpose - VPP (Amber) + load shifting at home. If you export lots in evening to make profit you may not have enough for the house. In the end it can also be too much work.

So sum up all the bills.
Total net cost in cents /total grid supplied power kWh

Once I put in the 48kWh battery I will be using OVO.

 

[DC3]

Remember that it is more difficult to use the battery for dual purpose - VPP (Amber) + load shifting at home. If you export lots in evening to make profit you may not have enough for the house. In the end it can also be too much work.

And with a Tesla PW3, the 10 year warranty is reduced to 7 years if exporting to the grid.

 

[Quickstatus]

the 10 year warranty is reduced to 7 years if exporting to the grid.

I thought it changes from 10yrs unlimited kWh to 37MWh