Hi, dont know if im in the right place to ask, Ive got Sunburst Solar 2 kw system, i live up Swan Hill way, my solar only produces 4-4.5 kw per day, yet my neighbors 2kw system produces 8-10+kw per day it not a sunburst solar system, we are both dead north, 30 degree roof pitch and no shading,any reasons for this?
Thanks
Are solar panels worth it?
(123 posts) (31 voices)-
Rtoll
MemberPosted Monday 3 Sep 2012 @ 8:59:07 am from IP # -
Russell Moore
MemberRtoll, something is very wrong with your system, if what you are telling us is correct. My first thought is that you need to contact the installer right away, and ask them to come back and do an inspection.
Check out the pvoutput.org site to see what others are getting out of their systems near you. Good luck.
Posted Monday 3 Sep 2012 @ 12:23:43 pm from IP # -
olfella
MemberI agree Roger, something very wrong with Rtoll's system.
I'm in Sydney, magnetic north alignment, 30deg, unshaded all day.
My 2.4kW Sunpower/sunnyboy system has been in for over two years now & has averaged 11.94kWh/day since installed. With today's sun & a few passing clouds, it generated 13.9kwh.
Mum's is a similar 1.8kW system & has averaged 8.94kWh/day.
I know Sunpower are higher efficiency panels compared to most, but a any 2kW system aligned as stated should be at least equalling 8.94 figure, if not more.If that is all you've been getting from the start Rtoll, then there must either be an equipment or instal fault. I'd be getting the installer back if I was you. If not an electrician familiar with solar to check it out, if you can't do any good running the original installer to ground.
Posted Monday 3 Sep 2012 @ 2:49:47 pm from IP # -
Sunshine
MemberOk, so 12 panels should equate to 2kw of panels.
Generally you should see around 1600w during the peak of the day, maybe a little bit more.
The roof being live when wet is not only dangerous but indicates the insulation of the cabling more than likely has been cut and you are getting a leakage of current to earth, hence your low figures. Contact your installer ASAP.Posted Wednesday 5 Sep 2012 @ 10:18:19 pm from IP # -
Buyer beware.. I have had two customers this week ringing me asking me to fix these problems with systems..I build wind systems not solar but they still keep rin ging me to fix them..I think this is a huge industry wide issue..No point ringing me or anyone else ring your original installer or take it up with the CEC council who issue these licences...Lets run a general rule of thumb here in Swan hill yopu shopuld have at least an average of six hours a day sun producing capability so on average you should expect no less than 12kw a day from a 2kw solar system in your location..I built an off grid solar/wind sytem for a customer out that way, the 2kw solar is showing up over the last six month period with about 11 kw avearge a day and the 5kw turbine is averaging about 50kw a day in same location.If you do not think your solar system is performing it probably isnt so ask someone who has been installing solar for years to look at it, I know of one electrician who is fixing on average two of these badly performing grid systems a day..
Posted Wednesday 5 Sep 2012 @ 10:30:57 pm from IP # -
Rtoll
MemberI been trying to get someone to look at the system from day 1,and nobody wants to look at it, but the live roof was noticed over 1 year ago, a plumber got a boot from it, CEC aren't interested, Energy Safe sent me a letter get it fixed. So I'm getting nowhere fast
Posted Wednesday 5 Sep 2012 @ 10:44:57 pm from IP # -
Well it costs money to get an electrician out there , there are some willing to travel but it depends on how much you want to pay....but no doubt its live and sounds like one string is not properly connected...I would be riniging your original installer and insisting it gets fixed..I have dropped by and looked at some peoples for free but the sheer numbers make this too much of an issue to keep doing.The name you threw up there is still in business but since I have had "interesting" dealings with said company I am sure many other people are in same boat as you.
Posted Wednesday 5 Sep 2012 @ 11:04:17 pm from IP # -
johnmath
MemberRtoll, do you know what brand of panels and inverter you have? My SMA inverter has a protection system for ground faults (shorts to the roof) and will shut down, but maybe your roof isn't earthed? You may get some leverage by contacting the supplier of the inverter. Reputable companies (like SMA) don't want their reputation being trashed by cowboys.
First some basic questions: you said your panels facing north at 30 degrees and you do not get any shading, but what about TV antennas or chimneys? Even a small amount of shading can effectively shut down one of your strings unless the inverter has separate MPPV tracking for each string. Some inverters, such as my SMA SunnyBoy have dual inputs but only a single MPPV tracker which is a bit of a trap unless the two strings are identical and have identical insolation.
If you momentarilly switch of the AC isolator to the inverter, you should be able to read off the open circuit voltage of each string, until such time as the inverter re-syncs and connects back to the grid. Check your documentation if you don't know how to read the array voltage.
In sunlight, of course, the open circuit voltage should be six times an individual panel's open circuit voltage, which will in the documentation. If you can’t find the specification, you can work it out near enough by multiplying the number of cells in a panel by 0.49. For example, my panels each have nine rows by 6 columns of cells: 9 x 6 x = 54 x 0.49 = 26.46 volts. A string of 6 panels will be ~ 26.5 x 6 = 159 volts.
Troubleshooting a system isn't rocket science, but there are safety risks involved so should only be undertaken by someone with at least basic electrical theory understanding. There are some tips below if you feel competent.
To shut down the system for troubleshooting, FIRST turn off the AC breaker at the fuse box or electrical board, THEN turn off the DC breaker next to the inverter. There will also be another DC isolator at each array, but if there is a risk that the roof is live, don’t get on the roof – this needs to be left on anyway to do the next test.
You said you have two stings of six panels. Each string has the six PV panels with a positive and a negative lead -(+)PV(-)- “daisy chained” together as below:
-(+)PV(-)--(+)PV(-)--(+)PV(-)--(+)PV(-)--(+)PV(-)--(+)PV(-)-The basic principle of joining together the leads from six panels in series with polarised connectors is simple enough to be done blindfolded. If you don’t get the correct voltages, there may be a faulty panel, any incorrectly wired string, or a wiring fault.
Once the system is safely shut down, you can unplug the two wires (one positive and one negative) for each string from the inverter. The voltage is measured from the (+) at one end of the string and the (-), i.e. the two far ends in my outline above. Note that this is a potentially lethal voltage and must be measured with care (don’t touch the metal electrical conductors!). You measure this voltage for each string, first across the two wires from one string, then the two wires from the other string.
If you have unplugged the BOTH wires from BOTH PV strings from the inverter then it should be electrically safe to get on the roof, but don’t touch the array until you shut off the isolator next to the array. Then it is safe to check that the strings are actually connected properly and that the cables are not damage or crimped between the panels and the frame or the frame and the roof. Once you unplug each PV panel from the string, it becomes safe electrically.
There is a good discussion on testing individual panels here: http://forums.whirlpool.net.au/forum-replies.cfm?t=1945625
I have tested all of my panels as described near the end of the discussion with 2 x 50 watt halogen globes as suggested in this thread, using a test rig I made with some old downlights and a solar extesion lead cut in half to give me a (+) end and a (-) end.
Posted Thursday 6 Sep 2012 @ 1:21:01 am from IP # -
johnmath
MemberRtoll, in my long winded replay (sorry) I lost my original train of thought about the possibility of mismatching of the strings and the inverter. Six panels in a string could potentially be too low a voltage for some inverters. If you post the make and model for the inverter and the panels, I have look up the specifications and check.
Posted Thursday 6 Sep 2012 @ 2:15:03 am from IP # -
johnmath
MemberFirst I must stress I have no direct experience with these products, nor am I an accredited installer. I am an electrical engineer by training, but my career has been in electro-acoustics. When you say you have two strings of six panels, I am assuming you mean two electrical strings, as opposed to two sets of panels all connected in one series string.
The inverter specifies a MPPT input range of 250 - 450 volts, but two strings will supply only 144 volts at peak output, so it is likely that the inverter is unable to calculate the optimum V/I power point for the arrays at any given moment. It would be preferable to have all the PVs in one string from this point of view, to bring the input voltage up to 288. You can check the DC PV voltage by pressing the Function button four times.
The inverter documentation only shows one input. Therefore if your system is configured as two strings, then the installers must have joined the two strings together electrically externally to the inverter. Two strings joined this way can under underperform if one string has some shading.
The inverter manual states that it has fault detection for ground and isolation faults. If such a fault is detected, it should shut down and light the red LED, instead of green. It's not clear then how the plumber could have got a boot off your array.
It's also possible that high local grid voltages are shutting down the inverter. This can happen when there are lots of PV systems, but the utility company hasn't compensated by adjusting the local grid voltage. When the sun comes out and all the PV systems start feeding the grid, the grid voltage goes up, which can cause an inverter "Grid Disturbance" fault, causing it to shut down (red LED) until the grid voltage drops.
There doesn't appear to be any logging of faults in your inverter so there isn't any way of knowing what's happened historically if you are not there to see it. Have you monitored the grid AC voltage on the display? The inverter will shut off at 270 volts or lower depending on the firmware setting in the inverter. If this is the problem, you may need to get the utility company to adjust grid transformer tappings in your local grid, or get the inverter company to update the operating firmware, depending on which item is outside of the standard.
Finally I would repeat that the effect of even slight or intermittent shading should not be underestimated!
Posted Thursday 6 Sep 2012 @ 8:53:09 am from IP # -
I think you are on the right track Johnmath with your assessmenty on the low voltages per string.., the lesson for everyone here is yes you can buy cheap solar systems but then the quality suffers..its far better to use a good quality inverter like the SMA which has far more functions, accesibility, data storage and grid protection than the cheaper offerings on the market..sure you can buy cheap but the costs down the road add up to far more than if you bought a quality system in the first place.I had an 80 year old gentleman drop by to see me the other day he had bought a 1.5kw solar system two years ago but it was not taking anything off his bill despite his main use only being lights and tv....Feeling a bit community spirited I went and had a look ...the system was working but it was not connected to his meter!!!..So I sent an electrician there and fixed it for free...the problems with poor quality solar systems are just starting to show up..I see a future full of poor performing systems needing major upgrades...
Posted Thursday 6 Sep 2012 @ 10:39:18 pm from IP # -
Jeffrey Jones
MemberOn the subject of quality and efficiency, how do Trina panels and Clenergy inverters stack up? We've just got a 2.1kw system and our best return was 17.5kwh over two days
last Sunday and Monday. We're averaging 6.5kwh since mid July.Posted Friday 7 Sep 2012 @ 2:51:40 am from IP # -
Russell Moore
MemberJJ,check out pvoutput.org, and find someone close to you who is posting results. Don't forget to click on the different attributes to bring up information on what systems they have. I'm in Sydney, and I get full sun from 8am to 4.30pm, and at the moment on a full sun day I can get 5.5kWh per kW. At that rate you should be getting 11.55kWh a day.
Posted Friday 7 Sep 2012 @ 3:07:35 am from IP # -
Rtoll
MemberI have 2 solar inputs on my cms2000 inverter, it wasn't a cheap system that the salesman sold me,but what was installed is another matter,yes buyer beware, all the solar panel cables are lying on the roof, I'm disabled so I can't do anything about it, but one day I might find someone to check the system out
Posted Friday 7 Sep 2012 @ 3:13:44 am from IP # -
johnmath
MemberTwo last thoughts Rtoll.
Where are you getting the figure of 4-4.5kWh per day, from your electricity bill or from the inverter? The electricity account doesn't show what you generated, just what you exported. What you export is less than what you generate, because you use some of what you generate yourself. To see what you have generated, you have to read the value from the inverter.
Secondly, are you talking about average annual generation or current daily generation? No two kilowatt system anywhere in the southern half of Australia is producing 10+kWh per day at the moment.
The 2012 daily averages in Swan Hill adjusted for a 2kW system are for May 4.5kWh, June 3.5kWh, July 3.9kWh, August 5.3kWh, September 7.1kWh, whereas the yearly average for 2011 was 8kWh per day. In December and January you can expect 12.5 kWh per day average from your system. See: http://pvoutput.org/list.jsp?id=941&sid=737
Posted Friday 7 Sep 2012 @ 3:50:42 am from IP # -
Perhaps yopu should use this scientific analysis to determine your daily sunshine levels for output..
http://www.auses.org.au/wp-content/uploads/2010/08/ASRDH_cover_contents.pdfThis gives you the daily AVERAGE hours per location....at Swan Hill its about an AVERAGE seven hours of sunlight per day... now this is average so multiply that to get AVERAGES.A solar system of 1kw should give a theoretical output of 7kw a day but lets reduce this somewhat for efficiency losses and say minimum 5kw per day AVERAGE over a year..From my own data logging equipment on an INSTALLED 2kw system in the Swan Hill area its running an AVERAGE of 11kw a day output...but solar panels and efficiency are also determined by quality and if you install cheap stuff then its most likely you will not see efficient results..
Posted Friday 7 Sep 2012 @ 8:43:13 am from IP # -
I started to search for all the brands for ongrid inverters and created a spreadsheet sorted by price/watt.
I hope all of you can contribute to it so we'll know what is the cheapest product. I found the lowest price/watt to be 0.18$ . Lets see if we can find anything lower... Check my table here and post your findings so I can update it.
http://ongridmaster.blogspot.ro/p/brand-model-power-watts-price-watt.html
Posted Thursday 22 Nov 2012 @ 4:03:50 pm from IP # -
johnmath
Memberongridmaster said:
I found the lowest price/watt to be 0.18$ . Lets see if we can find anything lower...You effort is commendable, but I am not sure what the point of this is. Surely "cost of ownership" is more important than initial purchase price?
In a simplified sense, cost of ownership is (initial purchase price / years of service) * factor for efficiency * factor for non-interupted service.
The efficiency factor will vary depending on individual circumstances. I have an inverter which is around 91% efficiency and a 1.5 kW PV array average daily yield of 7 kWh, of which I earn / defer cost of buying power at an average of say 45 cents / kWh. If my inverter was 96%, that would be worth 0.05 * 7 * 365 * 0.45 = $57 per year, or $570 over the 10 year expected life of my inverter.
It is clear from posts on this and many other websites that there is considerable differences in MTBF (Mean or average Time Before Failure) of inverters, by brand. Some brands are only a year or two, whilst other brands are stretching out to ten+ years). I am not going to mention inverter brands here - anyone who wants to spend five minutes searching will discover there are no surprises that the German brands (and one in particular) are way above the others and the "cheap" brands are at the bottom of the list.
MTBF can be, and is, estimated by accelerated life testing, which is where products are stressed by running at an elevated temperature. There is a well known relationship between temperature and lifespan, so it is possible to calculate the MTBF in advance using these tests. In fact by knowing the MTBF of the components that are used in construction, it is possible to design a finished product to achieve a specific MTBF. To extend MTBF, every component generally costs more. You can bet that the companies that copy other electronic circuit designs and manufacture at a low cost, don't even know about these things would not have the laboratory facilities to do the accelerated tests either.
Buying an inverter on purchase price alone is rather foolish and counterproductive - a race to the bottom. The cheapest inverter / kW is like to cost two to four times as much, or more, to own over the life of the PV system, plus there is the disruption of repairing a failed system and potential damage to other connected items to contend with.
Posted Thursday 22 Nov 2012 @ 8:23:06 pm from IP # -
I had thought that installing a solar photovoltaic system might give me some protection against long term problems with cost and reliability of the power grid.
It is quite a shock to see johnmath's discussion of a critical component, the inverter, having such an extremely short mean time before failure (MTBF)."Some brands are only a year or two, whilst other brands are stretching out to ten+ years."No, I don't think solar PV systems are worth it.
Posted Thursday 22 Nov 2012 @ 11:39:22 pm from IP # -
johnmath
MemberCatopsilia said:
It is quite a shock to see johnmath's discussion of a critical component, the inverter, having such an extremely short mean time before failure (MTBF)."Some brands are only a year or two, whilst other brands are stretching out to ten+ years."I should point out that my usage of the term MTBF is a little loose in this thread. Inverters have a MTBF but may also fail prematurely if they are poorly installed, stressed by electrical surges or heat. The better brands have greater reserve capacity for stress / better thermal performance and so on. Then if they are installed with due consideration (my inverter is in a cool shaded, breezy place) you should expect a decent service life. Hopefully I won't have a premature failure due to a lightning strike or a car crashing into a power pole in the street, for example.
My 2 1/2 year old system is only 6 months away from paying for itself. I have an SMA inverter and expect to get ten years plus service from it. If I have to replace the inverter, so be it. Thanks to supply and demand, a replacement inverter will cost much less per watt than the original one, and I can select a more efficient model and improve my PV system's performance at the same time.
Posted Friday 23 Nov 2012 @ 2:48:59 am from IP # -
PeterReefman
MemberCatopsilia said:
No, I don't think solar PV systems are worth it.
Cato, I find that an amazing statement to say now at the end of 2012, with solar PV having progressed to the point where it is all-but financially viable even with almost zero Govt incentives. And that's not even mentioning the environmental benefits.
Regarding inverters, yes they WILL fall over early - and this isn't limited to Chinese made inverters. My German inverter broke down after 2 years, but it was under warranty and was fixed. Simple as that. Almost all inverters come with 5 year warranties now, and even some Chinese are hitting the market with 7 year warranties and Australian offices to service from. Plus when you consider that continued R&D and economies of scale is making them both better and cheaper, they're really just not a risk (as long as you don't buy for the cheapest cheap price from a fly-by-night installation company importing without local servicing of course).
Honestly, when I bought my first system WAAY back in 2009 (yes, not long ago at all) the Sanyo HIT panels worked out to be about $1,750 each. Today a very similar (but Chinese) panel will cost a little under $300.
So high FiTs contracts are gone. John Howard's $8k is gone. The solar multipliers are almost gone. That's all true (and arguably good, especially the multipliers from a climate action perspective). But a well sized/designed system will still have a less than 10 year payback anyway. And while it won't ZERO a bill anymore (thanks to low FiTs), it will still reign-in an electricity bill to a far more manageable 50% or so.
One of the biggest problems I feel we have with the "Are solar panels worth it?" question is that we in Australia really did have it perhaps a little TOO good for awhile there, and now solar advocates and the industry has this looming challenge of trying reset people's expectations to be a little lower - It's not AS worth it, but still well worth it. From a financial AND climate perspective.
PS For transparency, yes I work in the solar industry. But it's a small outfit that
- I won't name
- Does not operate nationally
- and I very much doubt I'd ever supply a system to anyone reading this forum.
So take this as an "objective" opinion from inside the industry - and from someone who has been a passionate advocate for environmental sustainability and climate action long before accepting a job in a solar company.Posted Sunday 25 Nov 2012 @ 11:53:47 am from IP # -
Yes I agree Peter. The initial subsidies and Fits have done the job and solar is now firmly established. It will only grow from here. I see a lot of new homes now with solar hws and PV being installed post the big handouts as people realise it just makes good sense to do it up front.
Equipment made now is also reasonably robust and normal variances in manufacture will always occur.
Posted Sunday 25 Nov 2012 @ 9:18:53 pm from IP # -
Professor Tim Flannery says Australia installed more solar panels last year than any other country, but the renewable energy sector still has room to shine.
The Climate Commission has released its first major report on renewable energy, which shows Australia is doing well but is still under-utilising its renewable energy potential.
http://www.abc.net.au/news/2012-11-26/climate-commission-release-renewable-energy-report/4391764
Posted Monday 26 Nov 2012 @ 3:42:27 am from IP # -
dp.elec
MemberCripes Rtoll!! Get back onto Energy Safe before someone gets killed!
Try http://www.esv.vic.gov.au/For-Consumers/Emergencies
An electrical inspector should have checked the work and obviously needs to look at it now.
Good Luck
Posted Monday 26 Nov 2012 @ 10:56:39 am from IP # -
Buzzman
MemberTechnically, as I understand it from talking to the sparkie, the phrase "the meter runs backward" is, strictly speaking, incorrect.
The old spinning disc meters should simply NOT spin if you are on a NET setup and using your own power, then when your panels aren't generating enough to cover the load, the meter starts spinning again as you import from the grid.
Modern Smart meters don't spin so can't 'run backwards'.
The difference between a Gross tariff set-up and a Nett tariff set-up is that with a Gross install ALL the power generated by the panels is Exported to the grid, and ALL the power used in the house is Imported from the grid. You do not, technically, 'use your own power' at all. The export cable and the import cable are separated and separately metered.
With a Nett system, the house is connected directly to the panels (for practical purposes) and so any power generated is used by appliances in the house FIRST, and only if you produce more than you are using does any get exported.
The trick is to firstly REDUCE the amount of power you actually use, by changing to low watt bulbs, turning off stand-by power, limiting people's shower times (if electric HWS) and generally minimising every single use of power.
This then Maximises any export and 'credits' to your bill, and this in turn reduces your total bill. But only against the 'usage' component.
You still have to pay the 'service access fee'.
So if you want to get a "$zero" bill, you need to be exporting enough power to earn 'credits' to offset the access fee as well your usage.
So in an 8c/kWh export contract, you'd need to produce an additional 18kWh per day just to cover the access fee. This would require approx a 3kW system just to cover the access fee (based on access fee of $1.50 per day, which is what we're now paying).
A 3kW system is around $7K.
As you'd probably need an additional 3kW to offset even a modest usage, and you're up to $14K, which is equivalent to about 7-10 years worth of moderate power bills.
So it 'just' stacks up financially with a 10yr payback (ROI). Just.
For people using more power than a 'moderate' household, the cost could be significantly higher, sending the amortisation period out to 15 or 20 years.
Who knows where we'll be in 20 yrs??? Thermo nuclear???
For me, it was only worth doing because the FiT was so generous. Due to the reductions in usage I have made by being completely anal about ALL power usage, my household usage is down to around 3kW per day.
My 2kW PV system exports an average (over 2 years) of 7.8kW/day. So I'm earning approx $3.30/day or approx $300/qtr. And got no bills to pay. (Bills average $260/qtr, fully offset by export credits).
My $4700 (installed cost) system will have paid for itself by the middle of next year and I will have until June 30 2017 (when the NSW Gross FiT scheme ends) to save the excess to double the size of my system at that time so I can still have a "$zero" bill.
I would not advise anyone to go solar today unless thay can cut a 'like for like' deal with their retailer (ie: credit for export at same value as import cost).
At the 'wholesale' rate of 8c/kWh it's just too marginal.
And the joke is, the so-called "8c/kWh wholesale rate" is a fiction, as the actual spot price of power varies dramatically, and is sometimes as high as a few dollars per kWh according to research I have seen.
Be nice if, in this allegedly competitive de-regulated electricity market, we "solar generators" could opt for max pricing during summer time peak events.
But I doubt govt would even consider such a move, hence we're stuck with 'whatever the retailer is willing to pay'.
Posted Thursday 29 Nov 2012 @ 6:16:11 am from IP #
