Monocrystalline vs polycrystalline for small off-grid cabin - real world experience?

Hi folks, new here. Been lurking for a while reading the energy threads and finally getting serious about designing the solar setup for my small cabin build. I keep going back and forth between mono and poly.

I came across a nice selection of monocrystalline solar panel options while pricing things out and the efficiency numbers look great on paper, but I wanted to ask folks with actual boots-on-the-ground experience - is the extra cost over poly really worth it for a small cabin system (say 1-2 kW)?

The argument I keep seeing is that mono performs better in low light and has smaller footprint which matters on a small cabin roof. But some older threads here suggest poly is still plenty good for the money if you have roof space to spare.

Anyone switched from poly to mono (or vice versa) and noticed a real difference? Mostly running lights, small fridge, laptop, maybe a well pump eventually.

It's so dependent on location and climate, these absolute one or the other just aren't universal.

I found having small solar experiments about the home now has taught us a lot about which panels are right for our climate and use patterns,  and which not. That way, when we upgrade the roof, we can get the right panels on there for us and our needs at that time.

Ethan Bell wrote:Hi folks, new here. Been lurking for a while reading the energy threads and finally getting serious about designing the solar setup for my small cabin build. I keep going back and forth between mono and poly.

I came across a nice selection of monocrystalline solar panel options while pricing things out and the efficiency numbers look great on paper, but I wanted to ask folks with actual boots-on-the-ground experience - is the extra cost over poly really worth it for a small cabin system (say 1-2 kW)?

The argument I keep seeing is that mono performs better in low light and has smaller footprint which matters on a small cabin roof. But some older threads here suggest poly is still plenty good for the money if you have roof space to spare.

Anyone switched from poly to mono (or vice versa) and noticed a real difference? Mostly running lights, small fridge, laptop, maybe a well pump eventually.

the only thing that really matters at the size you are talking is to make sure to design around an mppt charger and dont lock yourself into a 12 volt system. The mono vs poly debate played itself out and the market decided mono won hands down. The only thing poly had going for it was lower cost and the price of panels kept dropping to the point that poly's advantage disappeared. They still exist from secondary manufacturers but I would never put one into my builds. Racking, labour and space are what counts now not panel cost.
Cheers,  David

I don't even pay attention to it.  I purchase all my panels used on Craigslist, and my single most important criteria is watts/$.  BTW, don't shy away from used panels because they are used.  I've gotten better performance from used panels I got off Craigslist then the brand new panels I paid retail for.  Depending on your location, expect a good deal to be in the range of 3-5W/$.  Don't order your panels on the internet with shipping.  Cash and carry local purchases will be the best deals.

I do bring a voltmeter with me when purchasing to make sure one panel doesn't turn out to be a lemon.  Don't buy a panel that has a Voc more than 10% lower that what the sticker spec states.  So, if a panel sticker says the Voc is 37.5V, don't buy a panel putting out less than ~34Voc.