> The panels easily pay for themselves over 30 years, so - yes.

But do they cover their opportunity cost?

The opportunity cost of what?

Of whatever else one could choose to invest in instead of the solar installation.

You can basically rationalise against any investment, because there is no limit to your imagined opportunity. Just keep the cash always so you always have the opportunity!

Does your opportunity cost computation cover the cost of not producing power from renewable sources?