[glxxyz]

> I’m guessing you’re not counting the fact that if you buy a stock for $100 you still have the $100 (you can sell the stock)

Your guess is wrong. A better term for what I calculated is the IRR of a series of cash flows. You're correct that stock is a liquid asset, I'm obviously aware that I can't liquidate the panels attached to my roof.

This whole thread got out of hand, I was just giving the anecdote that I saw a much better return on a heatpump than a solar installation. I don't care who believes or doesn't believe my calculations.

> Easy to verify though: what was your install cost and how much is it saving you on energy bills?

A rough estimate is given on my original comment in this thread.