I have recently received several quotes from a number of companies for solar systems at my house in Adelaide. My roof pitch is 27 degrees and the panels would be located on the roof facing the front of the road which faces roughly north. I'm currently looking at a 3.4kW system using 40x85W thin film CIGS Q-Cells and I'm interested to see what people have to say about them and their performance. Based on the system specification the average power generation is estimated at 14.6 kWh/d and a peak summer generation at 18.7 kWh/d. I have done a fair bit of research on the CIGS panels and they seem to get good reviews.
I was wondering is other forum members have used these panels before and what actual power output they have received compared to the estimated output? Does anyone have any comments on these panels? The system is going to cost around $14,000 so I just want to make sure my investment is worthwhile. We are fairly conservative with our power use and most appliances are turned off while we are at work. My largest power bill has been $400 during the hot summer of 2009/10 and averages $300/quarter. Hopefully this system will cover all of our requirements and provide sufficient feedback to the grid to offset our annual electricty costs.
Hi Jarrod. I have no direct experience with this technology: our panels are "old tech" mono. If you look at the live system information on this (DKA) site, system 27 is CIGS Thin Film Q-Cell. I assume this is what you have been quoted on. In comparison to all other non-tracking systems, it does very well. The next-best system is No. 17 HIT Hybrid Silicon Sanyo. I use the benchmark of the Solar Compass, system 16 which has North, East, West and Flat orientations and is "old tech".
If you look at the "Year" data, then for the period ending 1/9/2011(click in the last plotted interval to get the data), you have the following "Average daily energy output in normalised units":
27: CIGS Thin Film Q Cells 5.94kWh/kW 17: HIT Hybrid Silicon 5.46 3: Roof mounted Poly X 4.91 16: Solar Compass North 4.86.
This ranking and relative performance seem typical of the other periods in the year. The CIGS Q Cells appear to generate about 15% more energy for the same system size compared with the older mono panels. I do not know the relative expenses or what constraints are placed on systems to get any Premium Feed In Tariff (PFIT) in SA, so I'll leave the economic considerations to you.
Your output estimate of 14.6kWh/d for a 3.4kW system is equal to 4.3kWh/d for 1kW, which is close to the Clean Energy Council guideline of 4.2kWh/d for Adelaide. Given the Q-Cells outperform mono, you might even do better than this.
As you are conservative with your power usage, this should net-off your consumption over the year: it is 5,300kWh over a year. You can compare with your bills. If you receive a PFIT for exported electricity, you may even come out ahead on cost over the year; the PFIT may more than compensate for the service charge component of your bill. c*p.
Thanks for your reply and in South Australia we have the PFIT of 44c/unit and the electricity provider will top it up. The top up price varies between different providers. My quote is through Solar Shop and my friends parents have a very similar system and are impressed with the output, compared to their neighbour who has a same sized mono system. There is a big difference under low light conditions - the mono panels arent prouducing as well as the thin film Q cells. based on this observation and as you said the thin film Q cells are more efficient and seem to be worth the additional investment.
My neighbour has also just installed a 3.5kW mono system and their house is positioned the same as mine (roughly north facing, no shading, same SMA inverter (3800)) so I'm going to try and see if he is keen to continually monitor the performance of his system and compare it to mine.
It is great to be able to view the different pv system performance on websites such as this as it does help people interested in investing in solar products to make the right choice. Keep up the good work!
Hi Jarrod, great information. The prices of systems are so cheap now compared to 3 years ago when we were getting quotes: out-of-pockets for systems of mid to large domestic size (over 3kW) are about HALF what they were.
There are 2 levels of sophistication you might want to investigate if you are serious about monitoring your system, as I am.
(1) Tabletop display. I have the Fronius Display. It is a remote system monitor and sits on the dining table. Thus I can read out instantaneous system output parameters during the day, and in the evening (or also during the day), I can obtain the parameters for the day's output (or from system start-up to the time observed). It also has data from system initialisation. This is a whole lot easier than going out to the inverter, and in any case the inverter ceases displaying when the system shuts down for the day so I'd otherwise lose the full-day data. It cost about $600. The SMA inverters have a similar option called the "Sunny Beam".
(2) Full data logger. Fronius has an option for a full data logging card to be installed in the inverter. It can send the data to your PC, and even automatically to Fronius over the internet for data storage. In this option, you can set up an account at Fronius and monitor your system over the 'Net. The abovementioned Sunny Beam has a USB connectivity to the PC for data download and recharging ... could be the way to go. I understand that SMA has a similar internet facility.
There is also a web site called "PVoutput". There you can see other people's outputs, and register to log your own as well as gain extra features which are not available to non-account holders. c*p