Yep, sounds all too familiar. I installed a east/west facing set myself on our flat roof. Looking at dynamic power prices of the preceding year, multiplied by

Yep, sounds all too familiar. I installed a east/west facing set myself on our flat roof. Looking at dynamic power prices of the preceding year, multiplied by expected power output. Even wrote a simple space optimizer for this one time. But messed up some measurements so had to change on the fly anyways. The old adagium still holds: measure once and curse twice.