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goughy

Solar power, cost, installation etc etc

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Well, interesting appointment.  Glad my wife is here, cause I hate numbers.  This guy was from alliance solar, who are new in Qld but from Vic.  The system he was talking was 6.6kw with 5kw inverter, ET Elite Poly panels with Goodwe Inverter, both with 10yr warranties (costs 320 extra for 10yr on the inverter).  And 10yr on installation.  Had his funky way of working out how much daylight average in our area and was working out we could generate about 26kw a day, and based on our highest average usage of 32kw, with their financing options we can afford it.  This system is gonna be like $11.5k, which with the 8 percent financing it's total is about $14.5k over 7 years.

I'll try parkies solar quotes site next and see what comes out from that.  Not that I expected $4k, but $11k was more than I was thinking?  Maybe that's why the guy was wearing an RUOK t-shirt, because of heart attacks at the price?

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55 minutes ago, goughy said:

This system is gonna be like $11.5k,

That's ridiculously expensive for what are OK but entry level components. Are there some weirdly difficult access issues for your roof that would make installation difficult? Does the electricity circuit board need upgrading? Did they include the STC rebate (which would be worth approx $3.2k off the price for north QLD zone)?

For that sort of money I'd be expecting top of the line LG panels and a micro inverter system like Enphase. You don't need that unless you have some highly variable shading problems.

Most definitely seek alternative quotes.

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As to being from Vic, I presume that means they sub contract out the installation. As a rule of thumb it's far better the company you purchase from employs the staff who do the installation.

And if something doesn't go right, or there's a problem that needs fixing, having a reputable local company to contact and sort it out is much better than a sales team half a country away who will pass the buck.

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21 minutes ago, Alex Simmons said:

which would be worth approx $3.2k off the price for north QLD zone

Goughy is from Toowoomba. SEQ, so zone 3 unfortunately.

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As to finance, there are institutions that provide green loans for solar installation. Going rates are ~6-7%. Several credit unions and some banks do them. Shop around.

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1 minute ago, Ex-Hasbeen said:

Goughy is from Toowoomba. SEQ, so zone 3 unfortunately.

Yep.

Zone three is a multiplier of ~1.2 or thereabouts, the current deeming period is 12 years and current STC price is ~$35/kW.

6.6kW x 1.2 x 12 x $35 = $3.2k

Can use this calculator:
https://solarcalculator.com.au/solar-rebates/

6.6kW in postcode 4350 gives a rebate of $3.8k.

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He didn't look at a single thing, just sat inside and discussed.  Shouldn't be any install issues at our place.  I've submitted to get 3 quotes through that solar quotes site and also for their green finance partner to contact us.  

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Alex's description on previous page describes us perfectly. 6.6kw/5kw inverter, comb of N and W facing on 2 arrays for 21 panels. We have averaged 20kWh/day PV production over the last 28 days. Our net meter gets installed tomorrow. We have averaged 5kWh net consumption from grid over last 28 days down from 28in previous 3 months. One daughter away for 3 weeks helps!!!!

Goughy I would also use wattever website to compare electricity suppliers. I've realised the companies will only show you their solar plans if they already have a solar system registered at your address. use the wattever plan comparison and it lets you do a future solar instal comparison. i've just found a better plan for me to switch to after my new meter goes in. No frigging phone call follow up either!!

We drew down on home loan as it was best rate we would get and we wre replacing our roof anyway. 11K sounds ridiculous. 

Edited by Parkside
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8 hours ago, goughy said:

He didn't look at a single thing, just sat inside and discussed.

Drives me nuts this sort of shit. These are the sort of sales people who promise all sorts of things, then leave it to the subby to sort out the installation problems, and that's when you find out they can't actually instal what you were promised, or to do it will require extra costs etc. They also tend to have lots of "out" clauses which mean they can substitute the agreed kit with other brands/model.

Yes they can do a preliminary analysis with satellite imagery, but they can't see the detail of roof issues, they have not even looked at your electricity box, assessed where the inverter might go, what issues with that there might be (e.g. inverters need at least a basic level of protection from the elements, especially to avoid direct sun). Roof assessment might be something simple like placement of TV antenna or other roof objects that can affect the placement of panels, the sort of roof and attachment systems required (these vary), tilt management if needed, shading analysis. Plus what will actually look good. Well done  solar PV systems look good and fit in really nicely with the home design, while others just look shoddy.

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Yes, while my wife was all excited, he was far from convincing to me.  She was excited because his numbers showed her we could afford it.  I told her to be excited, cause if we could afford those numbers then we'll be able to find cheaper.

He wore an RUOK t-shirt, he can't have been all bad?  

Parkside - we only have one electricity supplier available to us, Ergon.  

I'm actually kind of hoping that now the Qld govt loans have closed that some may be offering some deals to get people installing again?

Something I realised we're not really thinking with regards to our usage, is that we don't hear our water with electricity.  So while or bill might be 800 to 900 a quarter, we still have another bill for our gas, which won't be reducing.  But it's part of our utilities....

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52 minutes ago, goughy said:

Something I realised we're not really thinking with regards to our usage, is that we don't hear our water with electricity.  So while or bill might be 800 to 900 a quarter, we still have another bill for our gas, which won't be reducing.  But it's part of our utilities....

Yes and your bills are pretty high considering you have gas HW + cooking. For reference our annual bill before solar was in the $4.5k range (no gas).

It's the air con. It's going to be the biggest energy draw of all. Water rates are generally a relatively low cost compared with power.

Of course we have only been talking about the supply side of the equation.

It's also possible to address the demand side. How energy efficient is the house? Are there appliances than could be replaced with far more efficient options? Is it possible to reduce consumption in other ways?

Our home, being a 1970s build, isn't particularly energy efficient. It's on my radar to work on that. Draft proofing, better insulation for windows (we have 86m² of single pane windows), and an update/improvement of insulation is also on my list of improvements to make.

We replaced our clothes dryer with a new heat pump highly efficient model. Of course we use the clothes line or indoor rack when we can but rainy/humid periods and shorter days sometimes the dryer is a necessity. The pool pump got replaced with a modern multispeed model and only uses 1/3rd of the energy the old pump did. Lighting of course is something to consider with new low power LEDs, but replace as required. Modern inverter fridges are more efficient.

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House is only 10 years old, insulation in ceilings and all walks, including garage, and tinted windows.  Many of our bulbs are leds, and replaced any downlights with led versions a year ago.  The dryer gets used a lot, but since I do everything and have to work as well that's a lifestyle trade off.  Only stuff that goes on the line are Sports clothing that shouldn't go in the dryer.  Nearly every appliance we own in the house has been replaced in the last 3 years, except for the cooktop and oven (and one of the elements in the oven is busted), so none of that will get replaced any time soon (I hope).  I knew we were a big user of power, but remembering that my workshop is powered from that as well; had I still been renting elsewhere that would have been another set of costs I don't even want to think about.  And we're on tank water and have a septic system so there's associated pumps etc running.  Someone told me his water pump was a big sucker of juice.  But yeah, that aircon in summer is a killer!  My wife was actually getting keen on getting a bigger system to feed more back into the grid to get closer to getting rid of our bill all together!  Eek.  With Ergon, the feed in tariff is apparently 8c.

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The size of system is dictated by a few constraints, aside from budget. Roof capacity is one, can only reasonably fit so many panels on a suitable roof facing the right way.

The other is what you are permitted to connect by the local distributor.

Normally approvals for connecting 5kW inverter systems are pretty much automatic (or really up to 5kVA per phase as long as inverter has reactive power control). Anything larger generally requires further approval processes by a human, and the limit of this approval will be 10kVA per phase.

So if you are single phase, then a 5kW inverter is what will typically get approved quickly and with no problems. Once you start looking at larger systems though, then the approvals are not so certain.

This is where the knowledge of a local installer helps as they'll be far more familiar with how the local distributor is treating new solar connections in your area. Sometimes with larger systems you apply for a large size but they only approve something less than that.

Ergon's Connection Standard follows the norm, however they may have specific restrictions in some areas. e.g. in my case I was restricted to a maximum of 3kW export per phase. In some locations the local transformers are pretty tapped out and they won't approve any export without someone paying for an upgrade (which costs bazillions).

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This is an estimate BTW of production by month for an unshaded west 6.6kW facing array. It's the AC Energy column that matters:

LvQVGTv.png

with these specifications:

iKvCW1T.png

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Thanks.  Man there's lots to go through and think of.

I'm getting 3 quotes through that solarquotes site (I have heard of one of the three that will be contact us), and then I'll ask around friends and get more.  We live in a pretty affluent neighbourhood (we're the poor ones), and lots of houses around here have 40+ panels.  

Just looking at our roofline, we have about 20mtrs of West roof that could take two rows of panels with only one plumbing breather port in the way, but at the edge of the roofline.  East I think we'd for even more.  North, maybe, just maybe could take 5 panels, maybe 3 more if they were fitted sideways.  But 3 gables facing north ruin the roof line.  But our roof gets zero shading all year.

I think my wife would live to go bigger and feed more into the grid to get our bill way down.  It just depends on what we can afford to pay back.  Currently she pays off or electricity bill fortnightly so when we get a bill, it's pretty small and sometimes in credit.  So we know how much we can afford to pay each fortnight.  We just have to make sure that the system specs, financing repayments, and remaining electricity bill are no more than, and preferably lower than that.  Then at least until the system is paid off we're no worse of than now, and once paid for much better off!

The guy that was here was saying that for larger systems you have to have two inverters?  Is that the case?  I've been looking at the houses around here and I've never seen two inverters, and in some cases can't see one at all so I'm assuming those houses have micro inverters?

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Ok, so that chart is estimating 9000kwh a year in production.  And looking at our bills over a year, we're using about 11000kwh.  But of course, much of our usage would be when the panels aren't producing.  The guy was showing us how it could reduce our bill by 80%, but I'm not really sure that would be the case?  To offset ever kWh we use at night we'd need to feed 3kwh into the grid (based on feed in tariff vs usage tariff).  

I'm hoping these other guys will be more thorough when they come, have more of a look around the place and maybe give us some sort of idea of our usage profile, cause that is something I'm not really sure of.

If a larger system over a 5 year financing term, with whatever bill we have left, was just under what we're paying now I'd probably go for that.  Of course, factors have to be sorted out that I know nothing about.  Guess we'll see what happens.

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2 hours ago, goughy said:

I've been looking at the houses around here and I've never seen two inverters, and in some cases can't see one at all so I'm assuming those houses have micro inverters?

Mine is inside my garage, behind a wall, so no-one would see it unless inside the garage. There's probably a lot like that Goughy. 

If you go over 6.6kW (5kW inverter) you'll need 2 as they'll likely limit you to 5kW feed-in on each phase. I assume you are 3 phase.

 

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Ah ok, didn't think of am inside install.  I don't have 3 phase here (that I know of).

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8 hours ago, goughy said:

Ok, so that chart is estimating 9000kwh a year in production.  And looking at our bills over a year, we're using about 11000kwh.  But of course, much of our usage would be when the panels aren't producing.  The guy was showing us how it could reduce our bill by 80%, but I'm not really sure that would be the case?

He's full of shit.

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9 hours ago, goughy said:

The guy that was here was saying that for larger systems you have to have two inverters?  Is that the case?

No, you can have a larger capacity inverter, however if you are on single phase then it will need to have the ability to limit the export to no more than 5kW if that is the limit you are permitted to have connected.

e.g. Fronius have both 6kW and 8.2kW versions for single phase (their Primo range of inverters) and they can be programmed to restrict export to the required limit. In the case of Fronius it will require having the Fronius smart meter installed as well (for single phase that's a few hundred bucks extra, and the installer can include it in the quote).

As to micro inverters, usually the only reason you go for those are:

- you have variable roof shading issues (which you don't). Micros manage that problem much better than string inverters can.
- you are keen to consider adding additional panels in the years ahead (much harder to do with a string inverter set up)
- you would prefer the electrical conduits carry AC from the roof than DC to the inverter. It is claimed the AC scenario is safer, but provided the DC cabling and conduits are done professionally, the risk is very low (there's that "get a quality installer" message again). Keep in mind there are 2 million of these things on Australian rooftops already.

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9 hours ago, goughy said:

lots of houses around here have 40+ panels

Average panel capacity has increased up quite a bit in just the last 18 months, but even so, 40 x 200W panels is still 8kW, so your neighbours have quite large systems if they are on single phase. Perhaps some have 3-phase power.

Panels now are typically 300W-350W capacity. Mine are 275W, I have 40 of them so an 11kW system.

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9 hours ago, goughy said:

maybe give us some sort of idea of our usage profile, cause that is something I'm not really sure of

Without hard data that's going to be hard to nail down precisely, but with some basic questions you can work out the likely self consumption ratio and do some numbers based on that. Being wrong by +/-10% doesn't make a massive difference to the payback.

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7 hours ago, goughy said:

I don't have 3 phase here (that I know of).

Show us a pic of what's in your meter box.

It's actually pretty important to know whether you are single or three phase, as it changes the potential solutions quite a bit.

There are quite a few advantages to 3 phase but it can also mean more expense to access them (e.g. 3 phase inverters allow for much larger systems, and with that much higher feed in limits).

You can still fit a bog standard cheaper and smaller single phase solution but there are some risks with that as well, especially the increased risk of high grid voltages on that phase. Hence in this case which phase the system is connected to needs to be chosen carefully, and an installer worth their salt will need to do a voltage record audit on all phases beforehand.

This is really important as being on a phase with too high a grid voltage can mean your inverter will throttle production, or even turn off.

Some don't give a crap about it and the home owner is often none the wiser.

But this is only an issue to resolve if you are looking to fit a single phase system to a home with 3 phase power. If you are single phase, well you have no choice on that.

Edited by Alex Simmons

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9 hours ago, goughy said:

To offset ever kWh we use at night we'd need to feed 3kwh into the grid (based on feed in tariff vs usage tariff).

To offset the cost, yes.

Some get a bit tied up with wanting to see a zero $ bill. While it's achievable it can also require an over investment.

IOW the first 50-60% of bill reduction can be done with a pretty modest investment. The next 40% may require a tripling of your investment. The returns are still OK, but they are not as good as the returns on that first 50-60% of bill reduction.

Our aim was to reduce bills significantly and do so with an excellent rate of return. So far our bills are ~1/3rd of what they were. IOW dropping from ~$4,800/year to ~$1,700/year. The $3k/year saving represents a 22% ROI.

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If we have 3 phase I'll eat my trannies hat!

 

IMG_20190726_075229.jpg

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10 years ago in Toowoomba was last Tuesday!

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Thanks for all the info and advice in this topic.

I'm doing some of my own numbers before I get quotes. One thing I'm not sure about is actual physical size of panels to work out how many I could fit on each roof segment. Of course I'm sure it varies a bit between manufacturers, but one random website said about 2.0m x 1.0m for a 300w panel. Does that seem reasonable?

Thanks!

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On 25/07/2019 at 11:26 AM, goughy said:

Thanks.  Man there's lots to go through and think of.

I'm getting 3 quotes through that solarquotes site (I have heard of one of the three that will be contact us), and then I'll ask around friends and get more.  We live in a pretty affluent neighbourhood (we're the poor ones), and lots of houses around here have 40+ panels.  

Just looking at our roofline, we have about 20mtrs of West roof that could take two rows of panels with only one plumbing breather port in the way, but at the edge of the roofline.  East I think we'd for even more.  North, maybe, just maybe could take 5 panels, maybe 3 more if they were fitted sideways.  But 3 gables facing north ruin the roof line.  But our roof gets zero shading all year.

I think my wife would live to go bigger and feed more into the grid to get our bill way down.  It just depends on what we can afford to pay back.  Currently she pays off or electricity bill fortnightly so when we get a bill, it's pretty small and sometimes in credit.  So we know how much we can afford to pay each fortnight.  We just have to make sure that the system specs, financing repayments, and remaining electricity bill are no more than, and preferably lower than that.  Then at least until the system is paid off we're no worse of than now, and once paid for much better off!

The guy that was here was saying that for larger systems you have to have two inverters?  Is that the case?  I've been looking at the houses around here and I've never seen two inverters, and in some cases can't see one at all so I'm assuming those houses have micro inverters?

They cut the breather pipe and leave it under your solar panels!!

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11 hours ago, goughy said:

If we have 3 phase I'll eat my trannies hat!

OK, single phase. But that old meter will need to be replaced with a modern smart meter - it'll be a requirement of the retailer. How, when and how much varies by location. I can't say if the rest of the circuit board is up to scratch - something for the installers to check and quote on. In my place shortly after moving in I had the circuit board upgraded to latest standard so it was ready by the time I got round to the solar instal. It was old school wired fuses.

My retailer (EnergyAustralia) arranged for the meter upgrade once the solar PV system was confirmed as having been installed. There was a wait - I think mine took 24 days from when the solar PV system was installed to when the meter upgrade was done. But the time it takes can vary, a lot. Some do it quickly, others take ages, months.

In my case there was no charge for the meter upgrade but in some jurisdictions there can be a separate fee for the meter upgrade.

You would do yourself a favour as well by talking with Ergon to explain you are looking at installing solar and to ask them what they will need from you, as well as what it will mean in terms of changing plans once that happens (you will be required to move to a new plan for homes with solar). They probably have some info on their website as well.

Once solar is in, but before the meter has been upgraded, technically you are not permitted to have the system operating. With those old disc meters when your system is exporting (production exceeds your home's consumption) they will either not move or spin backwards. When they come to fit the new meter they will take the old meter reading. If it has gone below your previous meter read, then you might find you are in a bit of trouble. At best they will make an estimate of your typical usage and charge you that. At worst they can fine you for tampering with a meter.

If you manage it carefully and strategically turn the solar PV system on and off to keep the meter from going below the previous meter read, then for the times you are exporting power you are in effect getting full retail price for your export. But be absolutely sure it is off when the meter guys shows up, having the system on when they show up does not go down well.

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Not that I can clearly trust anything the previous guy said when he was here, but he said Ergon take at least 8 weeks to come approve the system so it can be turned on.  I won't be dicking around playing with things, that's for sure.

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Gonna try and build a power usage profile over the next few days.  Finding periods of time when it's nothing more than maintenance, what my work shed is using, things like that.

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1 hour ago, goughy said:

Gonna try and build a power usage profile over the next few days.  Finding periods of time when it's nothing more than maintenance, what my work shed is using, things like that.

Goughy, do you know any sparkys that may have a power logger. This would give you an accurate view of what it's really like.

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Nope.  Will just do it old school.

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It's actually kinda interesting, taking readings at various times, etc.  The house seems to use about .42kwh/hr just existing, with nothing happening and no one home.  Using the dishwasher, washing machine, dryer, and charging the robovac plus working in the shed lifted that somewhat!  Interesting to see what happens when I'm sewing, or have the air compressor going, as I'm just pulling Furniture apart ATM.

Granted my numbers don't have big periods of time yet to base them on.

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1 hour ago, goughy said:

It's actually kinda interesting, taking readings at various times, etc.  The house seems to use about .42kwh/hr just existing

Yep.

This is the energy consumption plot for a day recently when we were away:

mjDCF1q.png

The lift at about 8:30am through to ~3:30pm is the pool pump, it runs at high speed for 5-min then settles into its normal cycle. The big blip at 1pm is the spa pump. That's just the pump, not a heater. Can see how this old style single speed pump is way less efficient than the multispeed pool pump. Other than that, the bumps up and down are the fridges cycling on and off.

This is a plot from midnight to 4:30am this morning. Bouncing around 350W. Fridges plus all the various devices on standby, be they TVs, computers, modems/routers set top boxes, clocks, night light and other devices and so on. They all chew up power.

Nrnh24H.png

When the fridges are off, the rest of the devices in the house are sucking about 180W. Over a year that's about 1,600kWh or about $250 worth of electricity (weighted average value of import/export tariffs).

So while I focus on all the big things (Pareto principle and all that), the little stuff adds up too.

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This is my cycle overnight, Between 180-280w fridge on and off. 

First small blip at 5:30 is me getting up, the next blip at 5:40 is my wife 😲😂😂

A9F88262-AEEA-418A-BF0A-31E1926635D8.jpeg

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Well, that we a better appointment.  Much much more conservative on what a system will generate, even saying he'll be too conservative.  Fronius inverter with REC panels and 12 years installation warranty.  $3.5k less than what the other guy priced for elite poly panels with Goodwe Inverter.  I can't remember the name, but another panel they happily use would be $1k less still.  He is emailing us copies of everything he went through.  The previous guy gave us a business card......  The first thing this guy did before going inside was look in the meterbox.

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It's been interesting taking meter readings the last few days.  I think my wife will be surprised.  I think she expected the shop to be a bigger drain on the power than it is.  I haven't had a day though where I'm sewing all day long, which would be different.  But so far Sunday we used 68% of our power overnight, Monday it was 48% and Tuesday 56%.  The big difference was monday I ran the washing machine, dryer and robovac (so it charged afterwards).  So far when talking to the guys we've worked on a 60 to 40% split of power used during the day vs night.  But the cost figures will probably be getting thrown a bit out of whack.  Of course, at the mo the aircon is running at night, but not during the day.

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1 hour ago, goughy said:

Of course, at the mo the aircon is running at night, but not during the day.

This will be largest single energy draw and likely to dwarf the rest. So the timing of AC use and how it changes with the seasons will be key to assessing likely self consumption ratio.

1 hour ago, goughy said:

So far when talking to the guys we've worked on a 60 to 40% split of power used during the day vs night.

The trick is translating the time of energy consumption into a self consumption ratio, as this is what determines the financial return or the value of the solar production or the amount the bill reduces by:

Annual return = Annual solar production * [self consumption ratio * import tariff] + [(1-self consumption ratio) * export tariff]

e.g. say:

Solar production: 9,000kWh
Self consumption ratio: 40%
Import tariff: $0.29/kWh
Export Tariff: $0.08/kWh

Annual return = 9000 * [(40% * 0.29) + ((1-40%) * 0.08)] = $1,476

As self consumption ratio increases, so does the return.

Keep in mind that the self consumption ratio decreases as the size of the PV system increases.

For reference, we have an 11kW PV system, an annual consumption (excluding hot water) of ~15,000kWh, live/work form home and our PV self consumption ratio so far is 55%.

Our self consumption ratio does vary a lot by season, by month so far:
Nov: 41%
Dec: 60%
Jan: 80%
Feb: 59%
Mar: 50%
Apr: 30%
Jun: 35%
Jul:  55%

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After recording the figures on the meter for nearly a week now, I reckon our usage figures a wrong.  I reckon, over a year the usage may be more so 45/55%, or even 40/60% day/night usage.  I'm guessing that would make a bit of a difference to the figures of what we can afford?  I get completely lost in all the payback, benefits, tariffs stuff.  All I wanna see is a decent weekly/fortnightly/monthly figure of how much we can reasonably expect to be paying for all our electricity and that we can afford that.  But as the daytime figure keeps sliding, I'm assuming the affordability of it slides too.  The last couple of days the day usage has only been 8.95 and 10.7kwh's, with dishwasher, washing machine and dryer running on one or both days.  But the nighttime usage as been 18.1 and 17.2kwh!!  But the previous few days the nighttime usage was about 5kwh less per day.  But the only daytime usage past 11kwh was Monday, where I did several loads of washing and drying, dishwasher etc.  I'm taking the meter readings about 8am, and 5pm.

Then, of course, we only have one electricity supplier available to us.  One of the guys that came told us that if we lived 10k away the flood gates open, and we'd be able to cut our bill by more than a quarter, but also get feed in tariffs over 14c.  So should we play the waiting game?????     Arrrrgggggghhhhhhhhh

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The thing to keep in mind is work out what energy you consume in the evening now that you can shift to daytime use. Washers, dryers, dishwashers are great examples. "Load shifting" is a great way to reduce your energy bill with solar PV.

Aircon is the biggie though and timing of use tends to be dictated by desire for comfort. In some cases homes can use mid afternoon PV production to pre-cool homes and draw less energy in the evening.

Again, once you have some data you are happy with, doing the analysis isn't overly hard and we can help.

 

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I'm not in this market but wanted to shout out to Alex for the amazing amount of detail and help here. :thumbsup:

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Bloody oath FP!  

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Finally got a net meter installed but now realise I haven;t got a smart meter so cannot look at energy balance easily. Quoted $600 for Solar analytics unit installed. Any others Alex?

July was a cloudless month in the main, averaged 20kWh/day with 6.6/5 setup. Best days on 24kWh.  Predicted average from installer was 15.

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I think I'm gonna wander the neighbourhood this weekend and chat to a few that have solar, see how they've found it so far.

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7 hours ago, Parkside said:

Finally got a net meter installed but now realise I haven;t got a smart meter so cannot look at energy balance easily. Quoted $600 for Solar analytics unit installed. Any others Alex?

July was a cloudless month in the main, averaged 20kWh/day with 6.6/5 setup. Best days on 24kWh.  Predicted average from installer was 15.

Solar Analytics is pretty good, it's a subscription model though so keep that in mind. The benefit of the Solar Analytics is they kind of do the all the number crunching in the models for you to tell you that all is good or whether there's a problem.

I have the Fronius meter since I have a Fronius inverter and they work together well. For string based systems I'm not sure I'd recommend anything other than these two meters.

Here's an article on them both.

https://www.solarquotes.com.au/blog/solar-analytics-fronius-smart-meter/

Your energy production is excellent. I get some shading issues over winter so that's the sort of output I'm getting from 11kW.

Edited by Alex Simmons

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Had a chat to a friend nearby who seemed to have a fairly big system, to see if they're happy with it.  They have a 25kw system with 78 panels and fronius inverter! Holly snapping ducks.  Very happy, their bill had gone from 4k a year to 1.2k back.  22k system will have paid for itself in 4 years.

Seems to me that the fronius inverters are the way to go.  My friend said 7.5k for the 6.6kw system seemed a bit expensive, but change or the REC panels to the other type they install drops the price by 1k.  Still waiting to hear from others etc.  Not gonna rush it.

I've kept a record of our usage over the last week.  Taking a reading around 8am and 5pm.  Used a total of 193.85kw for the week, with 82.55 during the day and 111.3 at night.  But the aircon has been hearing every night, and only once did the day for one afternoon.  So that's about a 43% to 55% day to night split.  It's expect that to even up over summer with a lot more aircon use during the day.

This is how the dude suggested the panels would fit.  The left side is east facing.  The West for starts get some sharing from the next house at about 4pm mid year.  It gets no shading in summer.

 

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