Bifacial Panels on Roof?

[billboe]

I'm looking to add 6 panels to an existing system and received a quote for 4 different panels available at my local supplier. It appears the best bang for the buck is a Hyundai bifacial panel. Is there any reason not to use this panel even though I'll get little (or maybe "no") benefit from it being bifacial (this will be a traditional rack install on a 8/12 roof).

Here are the 4 panels that are in stock (and ~400w) at my local supplier.

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While I'm at it, any info/opinions on this selection of panels is welcome!

[J.P.M.]

Some states limit additions to system sizes. Do VT POCOs or state/local regulatory agencies limit/regulate what can be added to an existing system?

[billboe]

Some states limit additions to system sizes. Do VT POCOs or state/local regulatory agencies limit/regulate what can be added to an existing system?

thanks jpm... my understanding is that they only care about the AC output (which won't be changing in my case).

any thoughts on the panel choices?

[J.P.M.]

thanks jpm... my understanding is that they only care about the AC output (which won't be changing in my case).

any thoughts on the panel choices?

So with larger STC rating but the same AC power output, you'll be clipping more?

On panel choices:
Since you ask, I'm not a big fan of bifacial panels, particularly when on a roof with a relatively low array standoff. Where's the advantage except in the advertising hype which, in the case of bifacial panels is unverifiable, mostly because of panel orientation and surrounding surface albedo with any enhancement over single faced panels usually vaguely stated with phrases like "up to X% greater output" which means under optimum conditions which I'm pretty sure you'll never see with an array sitting parallel to and probably less than 12" away from an angled flat roof in Vermont.
Then too I'm a big fan of KISS. Biggest reason being that bifacials are simply more complicated (more to go wrong).
Even for the same price for a single face panel, for the added complexity you're buying potential problems for what will be IMO only, not much, if any, increase in output.

Take what you want of the above. scrap the rest.

[billboe]

thanks again JPM!

So with larger STC rating but the same AC power output, you'll be clipping more?

yes, but i don't get a lot of clipping at the moment. i will be going from 113% DC oversizing to 139%.

On panel choices:
Since you ask, I'm not a big fan of bifacial panels, particularly when on a roof with a relatively low array standoff. Where's the advantage except in the advertising hype which, in the case of bifacial panels is unverifiable, mostly because of panel orientation and surrounding surface albedo with any enhancement over single faced panels usually vaguely stated with phrases like "up to X% greater output" which means under optimum conditions which I'm pretty sure you'll never see with an array sitting parallel to and probably less than 12" away from an angled flat roof in Vermont.
Then too I'm a big fan of KISS. Biggest reason being that bifacials are simply more complicated (more to go wrong).
Even for the same price for a single face panel, for the added complexity you're buying potential problems for what will be IMO only, not much, if any, increase in output.

Take what you want of the above. scrap the rest.

the reason i was drawn to the bifacial panel was because of the larger DC rating and the lower price (i was told that the 435w rating was without any added performance from the back of the panel). i wasn't counting on getting any benefit from the bifacial aspect of the panel.

so thanks for the complexity argument. i was also wondering if they were more prone to damage because i assume they are glass on the back of the panel as well...

the next best bang for the $ would be the jinko modules...