DM 158w Monocrystalline Solar Panel (2 Pack)

I'm a 1st time solar buyer, I have wanted to buy solar panels for a few years but too expensive, until now. I was very impressed with the overall structural strength of these panels, the aluminum frame really feels strong, and the panels don't flex in any direction. It looks like they use an anti-reflective glass to pass more light to the panels, and the cells themselves look to be very good quality, not a chip or crack or imperfection that I can see. Especially impressive since they traveled halfway across the country to reach me.I have not mounted them on my roof yet, but at a decent angle in my yard, they generated 267w of power - 32v @ 8.35a in series, with a 600w micro inverter producing 245w of AC power (measured by a Kill-a-watt meter). And with it being autumn, the angle of the sun is likely limiting these from producing full 290w of power. I would expect in mid-summer they will reach the rated power.I did receive the MC-4 Y cables, and was happy to find that the pigtails off of the panels are long enough to run the + to the - of the other panel with a little slack left over, and then the MC-4 connectors connect and the other end is simply a braided 12 gauge(?) wire. I had ordered MC-4 connectors in anticipation of needing them, and I don't think I will.The only disappointment is that it appears most solar panels do not line up with roof trusses, these are 26.5" wide, and my roof trusses are 16", and I have not found where to get the rails they show on professional installations, so I will have to figure out how to mount them securely on the roof.If my calculations are correct, in Indiana, I should be able to produce an average of 1.1kWh per day with these, once they're mounted properly on my south-facing roof with no shade from trees.I'm also considering buying another set of 2 panels once they come in stock, as I have not found any other panels of this output in this price range.Update 12/3/12- Very impressed after 3 weeks of use. I adjusted the angle on my roof for winter, and on one particular day, I saw the panels producing 308 watts DC. It must have been ideal conditions that day. Otherwise, in November, they seem to produce around 250w at noon. And they still produce 15-20w when it is completely overcast. Producing about 1kwh per day in northern Indiana, just what I was expecting. Can't wait to see what summer brings. But also hotter cells = lower efficiency, so will there be much difference in shorter winter days and longer hotter summer days? Only time will tell.

Pros:1 - Low low price2 - Highest peak power for off-grid applications3 - Excellent double-box shipping containerCons:1 - Large panel size2 - High sensitivity to shading3 - Low tolerance for non-optimal azimuthComments:** Full disclosure: I live in the northeast (Appalachian Mountains) in a wooded area so a lot of shading from trees, clouds and snow during winter months is normal. My comments reflect this scenario and are intended to assist others with the same situation.Since beginning my foray into solar, I have learned that the one constant is disappointment as the solar industry has no qualms about overstating performance figures. With the DM 145w panels, I was expecting far better performance than I get from my 100w monocrystalline panel and IT DOES in fact outperform it but it turns out that the theoretical advantage does not hold up under real world testing.In absolute terms, the performance of this polycrystalline panel is 45% higher than my 100 watt mono panel. Under a perfectly clear sky, I have measured 149w from one of the panels so it certainly performs above the published specification but that's pretty much where the party ends.The panel suffers from a very high sensitivity to shading and has little tolerance for non-optimal panel tilt. Peak power output is typically for only 2 minutes during the day and output drops off sharply afterwards (I have a data acquisition unit so I can see the output on a minute by minute basis). Throughout most of the day, it will yield about 90w of power where my 100w mono panel yields about 95w. Somewhat disappointing but it's solar... what's new.On the bright side (pun intended), despite the loss of efficiency on the top end, the low end performance is actually boosted. On a so-so day with clouds, rain and general all around gloom, this panel will actually generate power (my 100w does nothing under rainy conditions). I got 20 watt hours out of the pair. It also is worth mentioning that there has not been a day despite the weather conditions that this panel has not performed.So is this panel worth it? Absolutely! For small orders, this panel represents the best value in the industry.Would I recommend it? Despite it's real world performance issues, yes. The buyer of course needs to adjust their expectations. You will definitely get more than 145w but for only a few minutes during the day.Would I buy it again? No. For the panel size, monocrystalline panels can be had at the same price which will yield superior overall performance.Thanks for reading.

According to some tech savvy friends, the specs were awsome and because I joined the "Prime" club I got free shipping - free!!!!! shipping. The boxes arrived looking like someone had taken a hatchet to them and one of the panels was totally shattered. UPS picked them up and a couple of days later one of the boxes of two was returned. That was two weeks ago and I'm still trying to get the returned box picked up. Now the company MD Solar is offering another good deal but guess what now the shipping is over $300. I feel bad about giving this product a bad rating 'cause it is probably very good; I'm just very discouraged about this whole process.

I bought 6 panels of 158 watt each and 3 expensive 125 Amp batteries and Cobra 2500 watt inverter and Ramsond Sunshield Pro charge controller 60 Amps hoping to run one room with 2 computer light and a AC at the cost of $3000 and it cant do that, all I can do is run my computer and the batteries do not reach 100% in sun.Whom do you blame for the lack of performance, Solar Panels, Ramsond Charge Controller, Batteries or Cobra 2500 watt inverter all set up for 12 volt.I could have easily bought the Kit for 1.75 Kwhr for under $3000 and no hassle whom to blame if its a bum system!I would love to send it all back and buy a kit right here on Amazon.AjayNew Jersey

Good deal on panel, fairly quick ship. The package could use tape reinforcement on the ends as I watch the ups guy pick it up and the panel slid out,it wasn't damaged though.Unit put out proper voltage