Bifacial panels and inverter selection

[Moxi]

Morning, I would like to access the hive mind, with regards to selecting inverters to run with bifacial panels, please.

The first question is how do you determine the full capacity of the panel (front and back) and how does that then relate to an inverter? There seems to be a bit of a dark art to determining the output from the rear panel that I am not yet familiar with.

The second question does mounting bifacial panels require a different approach, all the videos I look at seem to use the standard methods with a rail running across the face of the rear of the panel which must reduce its potential ?

Thirdly do bifacial panels require specialist inverters to get the best output performance ?

Fourthly and slightly pre-determining the probable answer to 1 and 2 above, are they worth the extra cost / effort?

For context I have a south facing gable wall which has a textured render over EWI, the wall is painted magnolia and has a hi albedo on sunny days, the paving adjacent to the wall is a rough stone paver with a Cotswold stone colour finish so another light reflective surface. I am thinking of hanging 4 panels on a free standing vertical frame, the panels would be attached by hinges at the top cross bar allowing the panels to be swung from 90 degrees vertical to 90 degrees horizontal (should the occasion be required) and anything in between to suit the light conditions and season. I reality I see them being at 90 degrees vertical during winter and windy weather and in summer swung up at 30 degrees off the horizontal to catch the sun at good angle. The frame will be secured to and wind forces counter balanced by more gabion baskets which in the recent stormy conditions have performed exceptionally well on the bin store keeping the one mounted panel there secure despite a very exposed position.

The panels would each have their own inverter due to shading issues from a tree that stands opposite (cant take it down yet as the MIL is fond of it), I would add extra batteries to the house stack to soak up the extra production via the existing AC coupled DNO approved Hybrid Solis inverter, at a later date I will probably go down the route of changing the Solis for a larger 5 or 6kW Hybrid inverter to keep pace with the transition from LPG to a fully electric cottage.

Moxi

[nowty]

Your over thinking it, the extra power amount your going to get will be mainly on cloudy days when there is diffused sunlight, or when the sun is in non optimal positions, so won’t overload an inverter. In any case, with most inverters you typically cannot overload an inverter, they just power limit or current limit. You only kill 99% of inverters with over voltage and a bi-facial panel will only increase the current, not the voltage.

Just treat them as you would with any other panel using the standard panel output.

Maybe if you live in a desert with a very reflective background you might need to think about it a bit more.

[resybaby]

Friends of ours have a few bi facials mounted on the side rails and open rear canopy of their 50 foot yacht to pick up the reflection of the sun from the sea and the deck. From what they told me, the 'reverse' side of the panel doesnt generate much at all when compared with the 'face' side of the panel, but in their instal its worth grabbing everything.
Quite the install they have aboard. Four separate standalone invertors, battery banks and panels for guaranteed problem free power.
Currently on a two year long world cruise, left the Azores a few days ago heading to the Canaries.

[Moxi]

I'm only considering them as they are about the same price as standard panels on City plumbing and as you say Resy, it might not be much but its extra for not a lot of dollar so why not now that Nowty has cleared up my overthinking imagination. Kids and the wife are away next week for a short holiday while I stay home to dog sit and work - means I will have some quiet time to do my unistrut and gabion basket shopping list and start ordering stuff.

Found this earlier which might be of interest to a few folk on here:

https://assets.usesi.com/product-media/ ... ochure.pdf

Moxi

[resybaby]

May as well then Moxi.
just took my first look on the city plumbing page. Some excellent deals on there.
My first FIT system cost me £11.5k back in the day, now look what you can get. Scary cheap.