Solar Advice

[Marc]

The time has come for us to install solar at home, now a number of other renovation projectors have been completed. 

I started diving in and realised what a mine field the solar game is, so I'dm rather be armed with the right info from those that have been through the process and can make recommendations on size, need for batteries, Tesla Powerwall benefits, etc.

 

It's a large 4-bedroom, 3-living areas + Media Room home, with 12kW ducted HVAC, and potentially a 12kW heat pump for a soon to be installed pool.

The roof space is likely no problem, and facing precisely the right direction.

 

According to my Powershop app, we use on average 38kWh per day, faily consistently with peak usage between 3PM and 9PM.

I work from home and there's generally two of us here all day, every day.

I'm thinking we need a 12kW system to have a bit of headroom, and it seems the average price of this is around $13,000?

 

I had one quote today from LECA, using Jinko panels - didn't catch the invertor name, but it's only rated to 10kW. So to get ~12kW he wanted to use two of these inverters for $14K.

 

I've just filled out the quote request on solarquotes.net.au to get 3 quotes but would like to know more before I start talking to those companies.

 

Is there any other information I can provide that will help give us some advice? Thanks in advance

[betty boop]

might want to check this thread

 

 

 

[muriwai]

rmpfy? Is your man

[evil c]

@Marc avoid Jinko panels, highly recommend LG Neon 2 panels - 25 year guarantee and to within much stricter performance criteria.

Lot of cheaper panels start dropping off in power output after a few years.

 

I went with LG and a Solar edge inverter as had shading issues so excluded string inverters which would take out a row if 1 panel was in shade.

Fronius are the other good brand to consider.

I forked out around 12k before loan or subsidy for a 6kw system so  more expensive but out performs lot of similar size systems..

 

Went through Total Solar Solutions and they were one of the best companies I've ever dealt with, very professional and importantly ethical.

Do all electrical work too.

Recommended to a few other people and they are very happy customers.

 

Wouldn't hurt to get a quote  , hopefully do in your area.

[Irek]

I would be very careful with those panels. They are very bad for environment. 

 

"Thousands of ageing rooftop solar panels represent a toxic time-bomb and major economic waste unless Australia acts swiftly to keep them out of landfill".

 

"The last few years have seen growing concern over what happens to solar panels at the end of their life. Consider the following statements:

– The problem of solar panel disposal will explode with full force in two or three decades and wreck the environment because it is a huge amount of waste which is not easy to recycle. 1

– Solar panels create 300 times more toxic waste per unit of energy than do nuclear power plants. If solar and nuclear produce the same amount of electricity over the next 25 years that nuclear produced in 2016, and the wastes are stacked on football fields, the nuclear waste would reach the height of the Leaning Tower of Pisa (53 meters), while the solar waste would reach the height of two Mt. Everests (16 km). 2

 

– Contrary to previous assumptions, pollutants such as lead or carcinogenic cadmium can be almost completely washed out of the fragments of solar modules over a period of several months by rain water.

– In countries like China, India, and Ghana, people living near e-waste dumps often burn the waste in order to salvage the valuable copper wires for resale. Since this process requires burning off plastic, the resulting smoke contains toxic fumes that are carcinogenic and teratogenic (birth-defect causing) when inhaled. 2

Solar photovoltaic panels, whose operating life is 20 to 30 years, lose productivity over time. The International Renewable Energy Agency estimated that there were about 250,000 metric tons of solar panel waste in the world at the end of 2016 and that this figure would definitely increase. Solar panels contain lead, cadmium, and other toxic chemicals that cannot be removed without breaking apart the entire panel. "

[stereo coffee]

With solar panel installations I wrote to the ABC about this a few days ago

 

"Something consumers contemplating solar energy need to know, is the difference between parallel connected solar panel energy, and the much less desirable but widely offered series connected panels.

 

With parallel connected panels the user has approximately 17 volts and a lot of amperage to easily charge and store, in off grid batteries to be used at any time of the day. Conversion to 240v is then done with an inverter which recreates the AC waveform from a lower DC voltage

 

Almost like a professional con job, what is invariably being offered though, is series connected panels with no local storage. These provide high voltage and relatively low current. 

 

End users with series connected panels, are not able to power appliances at night from their solar panels, rather they receive a pittance of a discount approximately 4c per kilowatt, ONLY when their solar panel is producing energy. At other times they have NO advantage over a normally wired house. 

 

The wise installation would see perhaps a combination of both series, but  mainly parallel panels , IF and only IF the electricity provider offers a reasonable tariff reduction to sell back to them .   

 

The easy way to remember IS to ask if what is being offered has or does not have local battery storage, and will work at night without the electricity meter speeding up, when the appliance is turned on. 

 

 

[Addicted to music]

I’m going through the process again because the company I was dealing with has just refunded my deposit and we’ll  have to reapply for the solar rebate....

 

i did some more research, if you can afford it, consider Enphase micro inverters....  but it’s up to you....

 

A few good reasons

 

• Eliminates the possibility of a DC fire from occurring as there is a small inverter attached to every panel...  therefore no high voltage DC routed anywhere 
• Faster diagnosis of the circuit that can pin point which panel/inverter is faulty
• Unlike string arrangements if  shadows partially fall onto a panel the rest of the system will still work,  the panels that don’t have shadows falling will still work, so the rest of the System is still producing.

High Voltage DC can be installed safely but are harder to switch, they need regular maintenance  in case the wiring gets compromised.   Around 1.7% of house fires are caused by solar installations for what ever reasons, but the worst is the regulation to install isolator switches and it’s only compulsory in Australia and nowhere else in the world, yet we have a higher percentage of solar PV fires in the world.

 

 

 

 

https://safersolar.com.au

 

[Tony M]

Our investigation and experience endorses EvilC's opinion that LG Neon 2 panels are worth the (not-inconsiderable) extra cost.  We liked them so much we installed 60 on our larger shed, coupled with solaredge inverters.

 

We also installed 2 LG batteries, taking advantage of Simply Energy's VPP battery rebate scheme.  I think this scheme is limited to SA, but there are similar ones interstate.  The salesguy (CEO of the company) said it was the Simply Energy rebate was the first time battery installation made economic sense to him and that opinion made sense to me.

 

The clincher was when he told me they used only their own employees for the installation whereas many (?most) companies subcontract to various installers who they squeeze down to the lowest cost possible.  He promised a super-neat/high-quality installation with great attention to detail and he delivered on that promise.  I wanted the cables hidden in the garage, but was fine with exposed conduit in the "big shed" - it's a farm shed after all!  When snags arose in relation to computer communication between the big shed, small shed and the house, they provided the best solution as opposed to the cheapest, keeping to the original quote.  No stuffing around with wifi - they ran ethernet to areas I thought impossible to do at reasonable cost.  It's great having a modem in the "big shed" now.  I like Sonos and stereo in the workshop.

 

Overall, it's performing in excess of all expectations.  I'm ashamed to say our electricity bills were heading for $10,000.00 pa.  This is to be expected with a big house and RC A/C in winter and we're home most days.  Also, bore pumps, other pumps dam aerators etc etc.  And this is with me avoiding going over to the "small shed" to watch movies and listen to music in winter as it's just another large area to heat and it's no fun being rugged up because of the cold.  Anyway, our electricity bills have been significantly in credit since the installation 4 months ago and a payback in well under 5 years is a realistic expectation.   Part of this is having 3 phase so we can put up to 15 kW into the grid at a time.  Unfortunately we only get 15 cents per kWH, whereas my early adopting BIL is still getting 62 cents!  Still, we put $13 into the grid one sunny day when we weren't using much ourselves and this is not a rare occurence.

 

It's also kind of neat to be able to monitor all aspects of system performance on a computer or remotely on the phone app. 

 

Hope I've given you some food for thought from our experience so far, Marc.  Please let me know if I can add any other info that would be useful.

 

EDIT: Forgot to mention - we do have micro-inverters attached to each panel so individual panel performance can be monitored and this also helps with shading issues.  We removed one big tee next to the shed prior to installation and will decide next winter if another one needs to go.  The lateral spread of shade from tall trees in the depth of winter due to the sun's trajectory is amazing.

 

EDIT2 :  A side benefit is that the "big shed" stays MUCH cooler on a sunny day than it did before.

 

Solar panels on "big shed"

Batteries and inverter in garage

Inverters in "big shed"

 

 

 

 

Edited December 5, 2019 by Tony M

[frankn]

Solar is great if you don’t have a mortgage 

[frankn]

[Addicted to music]

@frankn

 

have you or anyone with a solar edge system had any problems?

[Guest rmpfyf]

@Marc I'd be happy to help via PM or phone if suitable. I work in the energy industry on these sorts of projects. I don't sell PV, batteries or home automation though I design systems, work with most of the major vendors directly and have helped out a few people here. I maintain some very complex homes for customers with all sorts of PV, battery and smart home combinations. I also design software to simulate PV, battery, VPP, smart hot water etc and would be happy to run your home through this if you're interested.

 

38kWh/day is not so bad, a bit over twice the state average but there's bigger out there for homes your size. A 12kW system is rather large and is likely to generate significant export in summer - even in winter most days - really depends what you're intending to do with the excess energy.

 

Assuming you're non-shaded you won't need a microgrid or hybrid microgrid system. I have zero issues with Enphase or SolarEdge - both are safe with arc faults, both are efficient systems. A SolarEdge system costs slightly less, can do a bit more in a smart home context, and is considerably easier to integrate batteries with. I would hold off on purchasing batteries if you're so intended - there are some solid new choices to connect to such systems within the year and it's going to be worth the wait. 

 

There are some good string inverters out there - Fronius is among the pick of the bunch (you can spend a lot more if you have specific requirements) though for a system that size you'll be looking at multiple inverters. If going string, invest in better panels as your system will be as good as its worst performer. LG Electronics and Sunpower are your two best bets (my own system is LG/Fronius). 

 

I assume if you're being quoted multiple inverters to hit >10kW that you're connected single phase? I'd be aware that there is no DNSP in Victoria (poles and wires company) that will let you connect a system that size without some sort of export restriction, so you'll need some form of export limiting, and it's therefore prescient to have some form of smart home connectivity that can use additional power when you generate it (assuming you're stuck on a very large system).

 

Storage is important but it doesn't need to be battery - consider what you can do with hot water and other demand response around the house. This will influence which systems you'd consider a good deal, as some are very amenable to this sort of work. If I was designing a system I'd be looking at making your hot water electric (done that here - very cheap storage), whether you have an EV and/or want to control charge there directly, what make/model of HVAC you have, how you'll want to control your pool, etc. Some systems interface very well with third-party control also, some have good APIs or IFTTT integrations, plenty of ways to skin the cat - really up to your poison and choosing a system in a complementary way. In terms of cost benefit, an 8kW system with good control over where energy goes can generate a ton more value than a 12kW system with none. Trick is not to bolt it on, be holistic about what you want it to do (e.g. SolarEdge customers on this thread are pretty well off here - the home automation suite, API sets and accessory range are all pretty robust and industry-leading). 

 

You may want to consider upgrade potential in your system design also. Some systems are amenable. If you're not already three-phase and your DNSP allows it, it's something you might consider. 

 

The audiophile in you might also budget for a decent line filter for your PV, and/or separate circuits, and/or (if you need it) a switchboard upgrade. I've even got people that choose this moment to install in-line power analysers, all is possible  

 

Happy to talk if it suits; at any rate hope the above helps.

 

@Tony M nice system! (would have put the comms and power lines in your batteries in separate conduits, though no biggie - they did well to hide wires in and out of the isolators, that's a really nice touch - and those labels they've used cost real money, can see from here it's an 'attention to detail' job, very nice to see). 

[mattd2308]

Have just recently had installed as well. Was fortunate to be part of the Vic Solar Rebate scheme. Had a 6kw system installed (Fronius inverter and 23 x 275 watt Suntech panels)

Being in regional Victoria has its benefits with having credible installer/electrician perform the installation. 

Was recommended by work colleagues, who stated he is VERY experienced with Solar Panel installations. Terrific bloke to deal with, he arranged all paperwork following the completion.

Notifying Powercor/CitiPower, and our retailer, Lumo Energy (who have been quite helpful) to convert and calibrate the smart meter for PV.

Has supplied and installed a few thousand  and well over 20 odd thousand panels. Stated has never had an issue with Fronius or Suntech Panels. 

Fronius, as others have stated, are probably the best inverters going around (Made in Austria)

Even the Inspector, who assessed his work for compliance  stated he has  never had any issues with this  electrician. 

[Guest vagabond]

We have 35 LG Neon panels and a Solaredge inverter.  Each panel has a power optimiser module that compensates for shade on some panels (otherwise you get lowest common denominator in a string, so if one panel is in shade that's the max output for the entire string).  I can even check real-time production and usage online, which is great.

 

Not a single problem after a year, and it will pay for itself in less than 5 years. As someone else said, the panels have a 25 year warranty.  Happy to this point, waiting on the next gen batteries to see if they have a better ownership cost than the current ones.

 

[aussievintage]

On 05/12/2019 at 2:52 PM, Marc said:

According to my Powershop app, we use on average 38kWh per day, faily consistently with peak usage between 3PM and 9PM.

I work from home and there's generally two of us here all day, every day.

 

 

This is exactly where I get to, and cannot further justify buying a system without a battery.  Two of us as well, and similar usage patterns, IOW we start using power just as the solar stops putting it out. 

 

I hear what @rmpfyf says about other storage.  Hot water storage is a great idea, but other than that and using a bit for aircon for a month or two in Summer, I cannot find any other daytime usage for the power.  It just has to be stored.  

 

So, I await reducing battery (or other storage) prices.

[Guest rmpfyf]

8 minutes ago, aussievintage said:

This is exactly where I get to, and cannot further justify buying a system without a battery.  Two of us as well, and similar usage patterns, IOW we start using power just as the solar stops putting it out. 

 

I hear what @rmpfyf says about other storage.  Hot water storage is a great idea, but other than that and using a bit for aircon for a month or two in Summer, I cannot find any other daytime usage for the power.  It just has to be stored.  

 

So, I await reducing battery (or other storage) prices.

 

Well... I just took delivery of my smart tank. Very happy. Effectively ~13kWh of storage that'll react faster than a battery, last twice as long as most and costs a third as much. No-brainer. I have a PHEV and two HVAC systems so plenty of demand response capability before I consider a battery. 

 

The Home Energy Management System that goes with the tank also accommodates a battery in future - I've got a client running one such implementation and its freakin' awesome. Stomps all over solar hot water.

 

I've upgraded from a Reposit Power controller, which is a very nice bit of kit - if anyone wants it I'd happily let it go at a very low rate for an SNA member. Reposit can be used with many batteries, all solar systems and some hot water controllers. There's also a nice IFTTT implementation and API for the hackers/smart home types out there. 

[Benje]

rmpyf

 

Smart tank?  Rheem system?

 

I'd like to link three appliances to a pool-price switch, and use the grid as my battery.

In winter, I have underfloor heating.  Happy to turn it off for a few 5-minute intervals or more if the price is high.  The house won't be that cool, and we can run the air-con when we need to (price allowing).

I have a large air-con, but the need isn't extreme for it as downstairs where we live doesn't get as hot as upstairs.  If the price goes high, happy to turn off and go see the neighbours or the local pub.  A bottle of wine at the neighbours and/or a couple of drinks at the local will be a lot less than the savings from having low consumption during extreme price events..

If I have pool price exposure, I'd even turn off the panels when the pool price is significantly negative.

 

I don't have electric hot water, so the Rheem Tank hasn't been an option.

 

I would use the SA residential TOU tariff with this arrangement if I can get it to go - run my floors early morning and during the day, with low network prices and using my PV output plus low pool prices..

 

Of course, I might be dreaming, and/or before my time.

We will see.  Just ideas now.  I'd rather do this and work with the grid than spend more money on trying to optimise my own PV output.  It also removes the ened for another big box (battery and/or tank) which is unlikely to get domestic planning approval.

 

Benje

[Guest rmpfyf]

27 minutes ago, Benje said:

rmpyf

 

Smart tank?  Rheem system?

 

I'd like to link three appliances to a pool-price switch, and use the grid as my battery.

In winter, I have underfloor heating.  Happy to turn it off for a few 5-minute intervals or more if the price is high.  The house won't be that cool, and we can run the air-con when we need to (price allowing).

I have a large air-con, but the need isn't extreme for it as downstairs where we live doesn't get as hot as upstairs.  If the price goes high, happy to turn off and go see the neighbours or the local pub.  A bottle of wine at the neighbours and/or a couple of drinks at the local will be a lot less than the savings from having low consumption during extreme price events..

If I have pool price exposure, I'd even turn off the panels when the pool price is significantly negative.

 

I don't have electric hot water, so the Rheem Tank hasn't been an option.

 

I would use the SA residential TOU tariff with this arrangement if I can get it to go - run my floors early morning and during the day, with low network prices and using my PV output plus low pool prices..

 

Of course, I might be dreaming, and/or before my time.

We will see.  Just ideas now.  I'd rather do this and work with the grid than spend more money on trying to optimise my own PV output.  It also removes the ened for another big box (battery and/or tank) which is unlikely to get domestic planning approval.

 

Benje

 

The smart tank is indeed a Solahart Powerstore (Rheem), and my current HEMS is by Combined Energy (for Rheem). It's to interface my EV supply equipment (Keba P20 I think from memory) and my 2 HVAC machines (a multisplit and a ducted system, which are both linked to one controller). I removed a gas tank because it's simply more economical for us this way. 

 

Pool price exposure requires having a retailer that will pass through some wholesale exposure to you. There are a few, and they usually use market schemes pertaining to virtual power plants to allow you to generate value from wholesale (pool) price movements (some implementations allow other market opportunities to be realised also). Tesla has such an offering through Energy Locals though it's for a battery only, there are a few others in your area though most are battery focused. AFAIK the only combination that'd work for you right now is Reposit Power with either Diamond Energy or Powershop, or SwitchDin with Amber Electric. I'd personally go with Reposit (you can PM me for the reasons), though if you want to do funky stuff, SwitchDin is probably a bet worth considering.

 

Aircon is easy for anyone to control. If you unit is DRED compatible you can control compressor load via closed contacts (relays). Otherwise something like a Sensibo can be used (which will give temperature control as well) with an IFTTT routine to do as you wish. Some controllers support Modbus or proprietary PLCs also. I have one customer that has an implementation able to work out when people are home, whether there's excess PV generation and - and will run the HVAC system accordingly with temperature setpoints that vary against time of year and ambient conditions. That requires no special control, though if you want for a demand response signal relative to pool price it's easy enough to effect from either a Reposit-type solution or via the aforementioned Ethernet relay and some simple software (done that before). 

 

Underfloor heating is also relatively easy to control. ToU arbitrage is very easy to implement. 

 

I wouldn't worry about negative pool price exposure vs PV export as currently regulation enforces your retailer to pay you no matter what the wholesale market is doing.... unless a retailer is willing to expose you accordingly and builds that into a hedging strategy (unlikely as variable export limiting is a relatively new thing in a regulatory sense, and even then it's intended for other purposes). 

 

Working with the grid is best though the economics of behind-the-meter generation (PV) are hard to ignore... I'd suggest aiming for both and winning  

[Benje]

rmpyf

 

Amber Electricity is doing a 1000 household trial in SA involving device control and pool price.

They got funding from the SA Government Demand management fund.

They do retailing through energy Locals with pool price membership.

 

It was in the paper today.

 

This program, coupled with the network TOU tariff, will be a good start.

The device control is only a single device (I think) - I'll try and do floors in winter and air-con in summer.

I think I have to commit to 12 months membership of Amber electricity.

 

Could be interesting.

 

I have been thinking further about this - it must be more valuable to do something with the market than to try and do it for self-consumption.

Why use a battery to supply yourself with energy which the market should be able to do easily, when the market values your demand response/battery etc more highly than the cost of the in-house energy saved.

A community solution must be more efficient than self-use - isn't free trade more efficient than trade barriers?

 

Benje

[Guest rmpfyf]

15 minutes ago, Benje said:

rmpyf

 

Amber Electricity is doing a 1000 household trial in SA involving device control and pool price.

They got funding from the SA Government Demand management fund.

They do retailing through energy Locals with pool price membership.

 

It was in the paper today.

 

This program, coupled with the network TOU tariff, will be a good start.

The device control is only a single device (I think) - I'll try and do floors in winter and air-con in summer.

I think I have to commit to 12 months membership of Amber electricity.

 

Could be interesting.

 

I have been thinking further about this - it must be more valuable to do something with the market than to try and do it for self-consumption.

Why use a battery to supply yourself with energy which the market should be able to do easily, when the market values your demand response/battery etc more highly than the cost of the in-house energy saved.

A community solution must be more efficient than self-use - isn't free trade more efficient than trade barriers?

 

Benje

 

Yes, that's the trial I'm speaking of with SwitchDin (who do the controls). 

 

From experience SwitchDin can control more than one device, and your retailer shouldn't care how many are connected as long as there's a response to a wholesale price event. The whole point of what sits at the edge of grid is to aggregate and mange whatever response lies behind the (your) meter.

 

Virtual Power Plants are dedicated to working with the market and sharing revenue opportunities.

 

It's not a competition with batteries for self-consumption - you can do both. 

 

 

[Marc]

Thanks for all the info and advice - sorry for lack of reply as I've been offline.

I understand a lot more now, but will check in with some more info ASAP.

[Addicted to music]

Here’s some info on the make of PVs

 

https://www.cleanenergyreviews.info/blog/best-solar-panels-review

 

 

[Addicted to music]

 

 

 

If  I had the money this would be my go to panel.  Note the solid copper grid plate that’s used for conduction.....   not sure about the cost, but I can assume it’s not cheap and would be on par with the LGs.  

Now do you really need this robustness when we also have flexible solar technology where you can roll it out for caravan use etc.....

Now the issue I have here is that if you’re on a budget like I am,  some of the others performed very well as long as you don’t have a cricket ball or 30cm hail stones landing or impacting on them....

Another consideration as watching the solar industry progress within a decade and you can see the changes, the specs get better, for example a decade ago the max was 225W, now you can get them to 400W per panel, multiple technology advances and almost 2x capacity as a decade ago,  we have hybrid and micro inverters to chose from etc etc.....    it’ll be  interesting in another 5-10yrs  to see where it’s headed with battery technology that’s steering away from Lithium ion.  

 

 

[Addicted to music]

On 06/12/2019 at 4:30 PM, Benje said:

rmpyf

 

Smart tank?  Rheem system?

 

I'd like to link three appliances to a pool-price switch, and use the grid as my battery.

In winter, I have underfloor heating.  Happy to turn it off for a few 5-minute intervals or more if the price is high.  The house won't be that cool, and we can run the air-con when we need to (price allowing).

I have a large air-con, but the need isn't extreme for it as downstairs where we live doesn't get as hot as upstairs.  If the price goes high, happy to turn off and go see the neighbours or the local pub.  A bottle of wine at the neighbours and/or a couple of drinks at the local will be a lot less than the savings from having low consumption during extreme price events..

If I have pool price exposure, I'd even turn off the panels when the pool price is significantly negative.

 

I don't have electric hot water, so the Rheem Tank hasn't been an option.

 

I would use the SA residential TOU tariff with this arrangement if I can get it to go - run my floors early morning and during the day, with low network prices and using my PV output plus low pool prices..

 

Of course, I might be dreaming, and/or before my time.

We will see.  Just ideas now.  I'd rather do this and work with the grid than spend more money on trying to optimise my own PV output.  It also removes the ened for another big box (battery and/or tank) which is unlikely to get domestic planning approval.

 

Benje

Smart water storage tanks are no good and will not last if they are not made of stainless steel.   Normally a stainless steel tank will inherent a 10year warranty replacement and even with this warranty make sure it’s specific that it uses stainless steel..   For any hot water storage solution ensure it’s a stainless steel tank, the cheap ones with have warranty of up to 5yrs  and are glass enamel metal storage that requires a self sacrificing anode to neutralised  the hardness in water that’s either alkaline or acidic so doesn’t corroded the walls of the tank,   These self sacrificing anode will need replacing every few years if depending on water quality. 

[aussievintage]

30 minutes ago, Addicted to music said:

requires a self sacrificing anode to neutralised  the hardness in water that’s either alkaline or acidic so doesn’t corroded the walls of the tank,

Your point is correct but I think you'll find the mechanism is a little different to that.  For a start, hardness is a different property to pH (acid/alkaline), but in this case it's neither. The electrode is combating electrolysis, which is a mechanism whereby electric current  causes one electrode to  be consumed.  The cure here is to provide a  convenient electrode that's replaceable, so that is consumed rather than the metal of the tank itself. 

 

32 minutes ago, Addicted to music said:

These self sacrificing anode will need replacing every few years if depending on water quality. 

Yes, because the more conductive the water, the more electrical current and the faster it consumes the electrode.