A month's real life data for some HF panels

[pvale]

Well, Early last month I bought a Morningstar Sunsaver MPPT controller and installed it on 2 sets of Harbor freight panels. During the installation, got a wild hair and decided to check the individual panels. Found 1 panel that had no output whatsoever. Called HF and they agreed to replace it. Took them until today to get one to me. So my data taking was started on 8/16 with 5 panels feeding the SS-MPPT. After a few days i did notice that the panels were making a bit more Ah/Day into the batteries than Ghurd's controller. Will keep it around for a future wind project.

My Excel data file is in my files section if anyone is interested.

http://www.otherpower.com/images/scimages/9602/Solar_output_Aug_16_to_Sept_16.xls

[mixerman]

Thanks for posting this information. I dont know what it all means yet but im working on it. I take it your operating a short wave radio and afew other things.

I have had no problems with HF in Crestwood store. Thay do seem to sell out as soon as they get them in. I have 2 sets of three I havent opened yet, sounds like I better check them out. I had rain checks in my wallet for 2 months, just got them last week. Still no batterys.

mixerman

[ghurd]

Wondering if you have an idea how much gain with the MPPT.

Might want to check each PVs output about 3 days before the warranty is up.

I would like to point out it is rarely cost effective in small systems because for less than the MPPT cost, another HF kit would give more output.

G-

[pvale]

Ghurd,

I think my daily output on a good sunny day was about 18Ahours before I put the MPPT controller on. I think it gained me about 2 Ahours per day. I am planning to deploy a third set that I have still in the boxes. I expect the change to 36V feeding the SS-MPPT will get them charging earlier in the morning, and later in the evening. I also expect the MPPT controller to get me more savings as the weather gets colder. Right now I monitor the array voltage ahead of the controller, and these HF panels drop to as little as 13.5V when they are hot. I bought the controller from Northern Arizona Wind & Sun, and the guy I talked to there thought this controller would help the HF panels in a big way. He had sold this controller to others that were using them on HF panels. I agree that the cost is probably not justified for most people, but part of the reason I got it was the data gathering capability. I have it hooked up full time to a computer and it's nice to be able to see whats happening in the system without going downstairs and looking at the E-meter. I'm a data freak, and that along with a couple of Watts Up meters, and the E-meter gathering data, I can get quite a lot of idea what the capability of the system is.

[ghurd]

The ~10% data and your expectations sound about like what I would expect too.

The peak amps look a little low, I would expect 5A without MPPT.

Wondering if the panels are at the 'proper' angle for the location during that month, or they are set for better winter output?

Could be the batteries were about full before noon, hot PVs, etc.

Just a little something to make data freaks itch. B-)

People (like me) would be interested in an update on the system every so often.

G-

[pvale]

Ghurd,

For 5 panels, I see a bit over 3A into the controller. I'll start recording peak amps from the Watts Up ahead of the controller. Also, I'll get a thermocouple mounted to the back of one of the panels for temperature. I don't think I've ever seen more than .75A out of one of those panels.

I'll post another months data after I get them seriesed into the controller, and with 6 panels.

The HF panels are really pretty poor panels as far as output goes. I've looked at the Topray site, and found data that leads me to beleive these are really 10W panels, Especially since they seem to put about that out as a max output. The only thing they really have going for them is the cost. Wish I could buy the panels without the controller and lights.

[wooferhound]

I don't have Excel

could you post the results in a text readable format ?

[pvale]

Woof,

I'll try to put it into PDF format. But you know you can go out and download Openoffice at www.openoffice.org. The Calc part of Openoffice will open Excel .xls files. There is a Linux and Windows version of it out there. If yer on dialup, that openoffice download can take awhile though.

[pvale]

Here's a .pdf version of the Excel file for those of you

without Excel or Openoffice. Had to delete the neat little

graph I put in it to show amperes over the month though.

http://www.otherpower.com/images/scimages/9602/Solar_output_Aug_16_to_Sept_16.pdf

[tecker]

During the time of peak production and heating alike the panels produce more from a parallel connection . The drop in voltage is due to expansion but the panels are producing max  amperage then , The way the junctions are configured for each panel make them poor series conductors and with expansion  this drop in conductivity limits power in a serial string . I see  this even in the multi crystal as well . I think the mppt will do better in boost mode rather than Buck mode also . I'll see if I can get the circuit for this unit . The interface is a nice touch .

[tecker]

 Looking at the pdf the controller is a buck mode unit looks like no boost section cutoffs are fron 11.1 to 12.1 though and a float is 13.7  I'll keep looking .

[tecker]

You can pretty much see if the controller's working by how much time it's hitting 14 plus voltage across the batteries . It sounds like it's floating the batteries .If the controller never hits 14 volts across the batts it's either not set right or the thing is only good at  7 plus amps .

[kurt]

pvale. i had to remove your comment do to some weird scoop malfunction messing everything up. sorry about that please repost.

Kurt

[pvale]

Well, a few days into another month with the panels in series for 36V, I have a few observations. It appears that the efficiency drops for the 36 to 12V configuration. Just logical, but may not be apparent if some people hook the panels in series from the get-go, and never see the controller operate with the panels in parallel. Before, with the panels in parallel, the temperature reported never got above about 27C in a 25C ambient. It's 1:00PM now, and I see the heatsink temperature at 41C. I also see a drop of about 5 Pk watts. this is consistent with one of the graphs in the namual that shows the efficiency drops to about 90%. I only get full sun on the panels from 11:00AM to 4:00PM. At 8:00AM this morning, I was getting over 1 Amp with the panels shaded. I am seeing quite a bit more charge before peak sun, and after 4:00PM until the sun sets.

I am going to keep the system connected this way throughout this month's data, to see what the monthly stats are connected this way.