...apparently cant add to the other thread of the same name older than 1 year!
Just installed a 12.7Kw solar system - 33 x 390W Hyundi panels, 33 Enphase microinverters
Almost completed needing:
- Electrical Inspector and Retailer side (metering/tarriff) to finalise.
- Install timers to control septic/sandfilter pumps and hot water to only operate during the day.
Other than that, changing habits so more appliances are used during the day such as Dishwasher, washing machine and dryer.
Our aim is to utilise as much solar as possible rather than rely in feedin credits as I feel they are on a limited life as more solar installs challenge (increased costs) the the network operators in managing thousands of "generator" added to the system with surplus power they don't need at different periods. At some point they will either stop or become next to zero benefits for the "generator" owner.
Looking at the chart, averaging 70% solar usage over network usage. Figuring with the change above, may be able to increase the average to 75% but obviously lower in winter.
The upshot is I may be able to pay off the system in as little as 3 years and reduce our annual electricity bills from $5,800 to $1450
I've a couple of projects on the to do list:
1. water tank on 25m hill to gravity feed water at mains pressure which will shift water pump usage to only daylight hours once a week
2. Install a wetback to the zero clearance fire for hot water - is now shelved as will see performance of solar electricity and solar hot water over the next 12 months
Initial charts indicate I have over capitalised as there is way more solar generated than is currently used and feedin credits (10Kw) consume and perhaps a 6 to 8Kw system would have been fine for 1/2 the cost.
But I guess over time, by changing habits and infrastructure (water tanks on hill, timers for pumps and hot water etc) to utilise more solar/power during the day, the usage will improve. It also allows for a point in the distant future to add batteries (when they make more economic sense to my situation) and if I ever venture down the EV path, to charge it up for free (...free in the context of post system payback period of 3 to 4 years)
Anyway's it now become a new "hobby" to see how much we can maximise the solar usage!!![]()
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Well, its been 3 months of solar power and really pleasantly surprised with the outcome.
By December, I'd installed 3 timers/contactors for the House hot water, Shed hot water and septic pumps circuit (ground water pump, septic pump and sand filter pump) so all only operate during daylight hours.
The shed hot water I'd only planned turning on occasionally however with the large solar excess, ended up leaving the HW breaker turned on.
As I've 2 phases and the network operator allows 5Kw feedin per phase but also has capped the amount going back into the grid/will pay for, so a total of 10KwH per day. This equates to approx $70 per month @ 6c per Kw with the current retailer.
Our "summer" quarter spend was forecast pre solar to be ~$1200+ due to greater solar hot water efficiencies which reduced to ~$190 and would have been lower if the timers were operational at the start of the quarter. As we are now billed monthly, our last bill was $25...partly due to a network outage re-imbursement. Depending on the winter solar surplus, I'II likely turn off the shed HW.
We are averaging 80% solar usage over a 24 hour period with most of the network consumption kicking in when the sun goes down
ie: During daylight hours 95 to 100% of solar electricity usage.
What I've learned from the system and subsequent analysis.
- Our previous high bills were predominantly due to the House hot water with no off peak and the septic pumps. The latter was a complete surprise as the analysis revealed they could be operating for several days at a time particularly during and after heavy rains on the sand filter.
- I've staggered the timers for the Hot Water and pumps so they are not all coming on at once to minimise the likeyhood of exceeding solar generation and therefore would require network electricity to top up demand.
- Moved appliance usage where possible to day time use (Dishwasher, washing machine, dryer)
- 12.7Kwh system is definitely way too big based on todays usage as a lot of solar is going un-used (similar to the graph I'd previously posted particularly given network operators now impose feedin limits which were never sustainable anyway and so a good thing to cap feedin quantities for the broader customer base. If I could do it again, I'd likely only install a standard 6Kw system for half the price and still achieve a 2 to 3 year payback.
- Tier 1 system with 33panels and 33 Enphase micro inverters, producing a nice easy to read view on what each panel is producing and more importantly if a fault occurs with a panel/inverter then its super easy to identify.
Future opportunities to use up more of the solar excess going to waste
- Install two 5,000 to 10,000 litre tank on the hill. I can easily get 20m elevation which will achieve main water pressure. Once installed, then all water pump usage can be solar generated to pump up during the day when required and have constant water pressure 24/7 including power outages which is our biggest pain in the rear. On a spur line and outages are reasonably frequent.
- Due to the excess solar generated, it leaves a lot of scope at some "futue" point for batteries (house/car) when they make more economic sense for me and the technology improves.
In hindsight, as I'm now un-employed as at the end of Dec 2021 and taking an extended break from the workforce for 3 to 9 months, the timing of installing the solar with reduced household incomes couldn't have been better![]()
Every time I see this thread title I think someone is right into astronomy, and that we are not alone![]()
here in WA I get 2.75c during off peak and 10c Peak for a grand total credit of $14 over 2 months.
I have just moved into a place with 2 systems for a total of 8kW (well, that is what the re blurb said).
I am pretty happy since my bill is 1/3 of what it would be without the solar.
Had to change my habits, eg put the air cond on during the afternoon to cool the bedrooms down before they get too hot so as to utilise the free sun.
I like the idea of an EV and/or a home battery but the costs don't add up.
It seems like the way to go in the future is to have an EV that can be used as a home battery.
EV chargers for V2G and V2H to arrive in Australia within weeks, after long delays - ABC News
That's interesting, I have been wondering how high I would need a tank to feed an auto retic system.water tank on 25m hill to gravity feed water at mains pressure
Wonder what the council would say about a tank on a 25m high stand?
Yes, I read that somewhere.
The 2 systems were installed at different times from what I can see, and there appears to be a small panel removed from the carport roof at some stage (underground wiring runs back to house, and looks to go to one of the existing inverters (disconnected)).
I had a rough read through documents left behind by previous owner and can't suss the real capacity - will need to delve more.
I have had a sparkie here (to replace the timber consumer pole) and he seems pretty ignorant on solar. There seems to be either solar specialists or domestic elecs with no cross over? I did ask him and he said it wasn't worth the extra annual license fee and he couldn't compete with solar cause they cut too many corners (going by the underground cabling at just below the surface I would have to agree). I am hoping to find someone good on solar so I can have a safety check and maybe improve the system(s).
I had a look around at how to monitor my system and am none the wiser. The inverters give a readout (PAC?) which seems to imply what they are generating.3 complete years, average export just on 10MWh, usage around 5MWh from a 5kW invertor and 6.6 of panels. On the flat rate so get a whopping 7c for export.
Still it's pretty much paid for itself already.
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The Synergy accounts are unfathomable.
I did find there was an upgrade possible to my meter box that would give me a readout of net usage but it involves a subscription based model and wifi (and the meter is too far from the residence for that). Something else to ask the solar specialist.
Monitoring largely depends on the inverter brand installed unless you install a complete stand alone monitoring system.
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I have a Fronius unit, which the easiest option is uploading to their website. That gives you the green bars (inverter output).
To be able to read my import usage (blue bars) in a compatible manner I had to install a single phase Fronius meter at the switch board.
For free it gives me a good number of monitoring functions, tho a couple of the advance options require a subscription.
I would say most sparkies have a basic knowledge on solar even if they don't install them. Solar is pretty cut throat so a unless you're specialising in installing them its not worth the cost of the fee's.
At a total guess without pics it sounds like someone may have snuck some extra panels onto the inverter, then removed before selling.
For the bill you will only get a total value for the period. "Export" = how much you sent to the grid during peak and off peak periods.
Then you will have something like "peak" and "offpeak" usage which is what you are buying from the grid.
Some good info on explaining AC and DC coupling to a grid tied system.
The challange is finding a cost effective AC coupled solution that I can add a small battery of say 1 to 5 kw thats enough to trick the panels into staying on during an outage and provide enough short term power during cloud periods during the day.
The main pain point during outages for me is the lack of water (no power to the pump), power to the solar hot water circulating pump and fridge/freezer. Happy to turn on a genset at night for a few hours where required.
https://www.youtube.com/watch?v=WVM0...nnel=altEStore
I used Solarquotes. They have lots of info on the current state of equipment quality etc. Through them it was easy to get 3 local quotes from installers that had good reviews and are available to quote/install in a reasonable amount of time.
It was years ago now, but after some research i'd pretty much narrowed my equipment down to Fronius inverter and REC panels. Maybe things would be different for me these days, but I've been really happy with my system, not a day of downtime
Used Solar quotes. They put you in touch with 2 or 3 recommended companies (which are constantly rated) and overall they were really professional (the companies I delt with). In general, found the quotes were all within each others ball park.
Also used the site as it has heaps of info with product rankings for panels, inverters, installers, pro's/con's of different solutions.
In the end it came down to (for me) Fronus or Enphase micro inverters. The micro's were a bit more expensive (2k out of pocket for the 12.7Kw solar) as opposed to a string inverter like Fronus but for me well worth it given the life of the system will be decades and probably still going long after I'm gone (panels are still producing 83% after 25 years) and you can easily see via the app what panel/micro inverter is playing up as opposed to a string of panels and one inverter.
Currently:
Looking into how I can make the system run during daylight hours during a power outage as they are all designed by default to shut down (with good reason). each to their own goals but for me, putting in a 10Kw "tesla" type system is a zero sum exercise with no payback. ie: current annual bill is forecast to be ~$1000/year, AC couple battery solution ~$15k therfor 15 years to break even with the battery performing ~4,000 cycles and likely to be end of life.
So my focus is to enable the solar to keep generating during an outage as there is heaps of surplus to power critical loads - fridge/freezer, solar hot water circulating pump, water pump (were on tank water) and septic pump with the ability to also plug in a sine wave generator. Likely to be an AC Coupled solution with a small battery and aiming for something less than 4 to 5k (if at all possible) purely for convieniance rather than payback on investment but with the capabilities to expand when the economics are more favorable.
Yep I hear you which is why I said "purely for convieniance rather than payback on investment"
Generally due to our rural bush location at the end of a spur line, every year we have unplanned power out for days at a time. Last year we had stints of 5 days when those big storms came through that had the dandenongs off in some parts for 6+ weeks, 3 days, 2 x 2 days.....plus 3 or 4 single days of planned outages. The single days arnt a big deal as I can roll out my small gen set just for the water pump (tap water & toilets) but even the smaller 2Kva gen set the wife cant pull start it.
For the longer outages its a matter of "me" rolling out the 8Kva gen set, 8 extension cords to fridges, freezers, solar water circulation pump, spare for a light/charges, water pump, fuel up daily etc etc which is a pain in the ar%e.
The easy solution is to put a bypass switch and gen socket at ~$1,000 and a new key start genset but just exploring additional options of getting the solar to run during daylight hours with a small battery to cover short periods of cloud cover. Much easier for the wife and young adult kids to flip a switch when I'm not there than to rely on them knowing how to set up and "start" a gen set.
Looking at the surplus solar, Typically outside of winter, in an outage scenerio we could easily run the whole house without batteries whereas winter it would be critical loads only however based on research a small battery is generally required to cover short periods of cloud cover and to trick the system into thinking mains is still on so the solar wont shut down..... only working in conjunction with a network bypass switch for obvious reasons.
Fair enough. "Purely for convenience" though, and to get you through the nights for those days-long outages, seems easier to get a big battery
Thanks everyone, very helpful points to consider + will give solar quotes a try as well.
Thanks,
Rob
Completed analysis of the first 12 months of Solar savings for 2022
Will obviously be different for everyone, as mine based on:
all electric house, HW House, HW Shed summer only, Tank water (no town supply), Septic pumps x 3, Solar hot water panels x 2
Not as good as I was initially forcasting.... thinking i was only going to pay ~$1,000 each year however the reforecast is a payback in 4 years
With an annual electricity cost of $2400 as opposed to $6000....a 62% annual reduction
Still opportunities for improvement such as
1. HW heated by a DIY custom wetback in the combustion fire but a difficult task being a zero-clearance enclosed fireplace,
2. there is insulation around the HW tank, but could do more and enclose in a DIY cover
3. Install a header Watertank on hill to pump during the day however ROI isnt there but great for power outages to still get tap water or flush the toilet!
4. batteries (changes my previous position where they provided zero return with a $1000 annual bill) - will need to perform a further analysis to determine what/if any battery solution may provide a good ROI although I suspect solving the HW issue for winter in point 1 will substantially reduce the bill and render batteries a waste of time from a ROI view point. Hoping costs will come down at some point as there is ~8MWh going to waste.
Winter reduction in solar generation takes a much bigger hit than I was originally thinking with some days only 10% solar utilisation as opposed to a summer's day of ~75% to 80 %
With the long-range forecast predicted to have the 2/3 years of wet change to dry (more sunshine), it's likely the annual bills will be less.
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