Hello,
I have been meaning to comment on this posting, but have been very busy lately.
My experience with these "cheaper" HF panels has been similar.
For a couple of weeks they DID do 40watts when brand new into my 12V batts.
But then they began doing less and less and less as the weeks passed by.
The instruction manual with the HF panels confesses:
"It is normal to see up to 20% (percent) degradation in amorphous silicon solar panels within the first 6 months life of the product before the amorphous coating stabilizes." -end quote
Well, my experience SO FAR is more like 50 percent degradation loss. The 3 panels now do 22 watts (1.6A) max in high, Direct, strong sun in the summertime.
I have bought TWO sets so far, and they both did the same exact 'degradation'.
I hope it don't go down any more! I got the first set a year and half ago, and the second set about 6 months ago.
I suspect my story is like many other new ones--- you don't have the $500 bucks to buy a quality 80watt solar panel and I was impatient to get started, so I got the HF for a couple hundred.
But now, I wish I had saved and got a quality 80watt $500 panel that will ACTUALLY KEEP doing almost the rated output for many, many years and last for 20 years and then you could sell them and get half (or more) your money back.
I am beginning to fear the HF panels may not last half that long.
Thus, I spent $400 for the two HF sets that together give me 3.2 amps (about 44watts// at 13.5v) in max sunshine. Whereas, if I had saved and got the quality 80W panel it would be doing 60-70watts (AFTER initial 'degradation) and last for decades. (This is what I have gathered from listening from others who have quality panels here) I personally have never bought and tested a quality panel yet.
So in this case, it looks like "You get what you pay for".
This is just my opinion and personal experience. I don't mean to offend anybody.
Maybe Others might get a little better results.
Maybe this is good for new ones to know, since they may decide to save for the quality panels.
Since I have almost no self-discharge with my fairly new (450Ah) battery bank, I still find them useful for about 400-450Watthours (Both sets) most days in the summer. So each day I get 2 or 3 hours of TV and DVD, couple hours of 5 watt lighting, and 12 hours with my 4watt big fan each night. So they still are useful and a good 'starter' set.
Those big Nicad batteries you have sure have a big self discharge. (over 100watthours a day looks like)
