Alternatively you could have two separate rows with a gangway down the middle. This would be safer as you wouldn't be walking along the edge of the roof but down the middle. Although if you raised them high enough then one row would start to shadow the other, I guess that by the time the sun got that low it probably wouldn't be generating much power anyway (early morning / late evening), so might not be too much of a problem.
It would also mean you aren't raising such a high sail-like structure as a single row of panels illustrated above. It would of course mean more construction as you'd need double the number of hinges / latches.
Steve.
