I don't see why the number of panels is so debated... ... Array's are a tier-branch that require the same number of panels that they replace, plus a storage device of the appropriate tier.
What if: the LV array's were made into a crafting-only item and couldn't be placed as world-blocks. ie: only use is as a crafting step to get to MV Array's?
That means you'd need 64 IC2 Solar Panels to be able to begin using array-based solar power. Plus whatever else is added to the recipe tree ie: solar circuit, that means the mat cost for a first array could be something like 64 Solars, 8 Solar Circuit's (? 2 AdvCirc, redstone, lapis, glowstone + some rare mat (EnderEye, Blaze Rod, ...) ?) + a center crafting slot (middle of the MV itself)...
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LV array (crafting only) = 8 Solar Panels + 1 'Solar Circuit'.
MV array (first array tier that actually generates = 8 LV arrays (64 panels + 8 solar circuit) + MV center slot (another high price array recipe, perhaps. An even more expensive center slot for the HV?)[/edit]
And let's have some fun... let's go better than a config that defaults to off... a config that defaults to off AND is undeclared... Meaning Array's would only become active after someone visited the forum, found the thread, and pasted the correct syntax into their config file.
I think that would make Solar Array's a suitable challenge both in-game and out. Anyone that keeps building solar after all that must be really dedicated to the idea...Yea? ...Nay?