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High power panels


  • Registered Users Posts: 312 ✭✭ idc

    Had seen mention of 700W panels just before i saw your post but in reality they are not really much better than smaller panels.

    I took my existing 310W panels which are approx 1.6m2. the JA 800W panel is 3.9m2 but although that is 2.39 times bigger the wattage difference is only 2.58. So it is slightly better but then again my panels are at least a year if not older. I expect these larger panels will make sense in large ground mount deployments but can't see any installer trying to wrestle an almost 2m x 2m panel up onto a roof!!

  • Registered Users Posts: 1,285 ✭✭✭ SD_DRACULA

    Yeah I'm looking at the ones which are roughly 2.3m x 1.3m, 6 of these would fit nicely on the front of the house, ideally 670w.

    What I do wonder is if they will actually reach their max output or is that just in lab conditions? For example my current qcells rated 335w consistently hit that in peak weather.

    And why would they wrestle with them, the guy that installed mine came with a van with a crane thing, lifted them all the way up to the roof 😀

  • Registered Users Posts: 2,718 ✭✭✭ graememk

    Big panels!

    But I look at the spec sheet for them, should tell you and compare to the spec sheet of the qcells.

    As peak conditions in Ireland is may + June because of the long days and it's usually cooler. Mine easily hit the 6kw limit of my inverter. But in the good, but really hot weather of July and aug, it never reached 6kw.

  • Registered Users Posts: 312 ✭✭ idc

    Ah a crane well then that's different 😀

    Mine and a few other installs I saw in progress was a ladder and scaffolding

  • Moderators, Sports Moderators Posts: 16,061 Mod ✭✭✭✭ slave1

    Higher watt panels all down to larger surface area, efficiency virtually nothing to do with it

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  • Moderators, Education Moderators, Home & Garden Moderators Posts: 7,394 Mod ✭✭✭✭ Jonathan

    This is exactly the point that people don't realise. The efficiency of all A grade panels these days are broadly similar (between 18% and 22% efficient). However, you may get more kWp on a given roof using smaller panels as you can better fit them to the shape of your roof.

  • Registered Users Posts: 1,285 ✭✭✭ SD_DRACULA

    You'd think that but between stupid roof design with many corners/apex there isn't much wiggle room.

    Barely fit 9 x 1.6m x 1m panels for a total of 3kwp, but 6 x 670w ones will let me maximize the 8kw on the inverter and who knows, why not throw the 9 x 335w panels on the back of the house even though it's N.