Engineering TV

But what is the efficiency loss.  Like she said, you don't get something for nothing.  Power loss from 100%?

This is identical, I believe, to what "Inphase Technology" does with their microinverter. A friend has 24 panels on his roof; at times, clouds/trees/etc. will shade a panel or two and the whole string is degraded in performance. By selectively cutting out non-producing panels, the string's output is not effected. Remember, when one panel is dark, it begins to act like a resistor, causing a significant problem for the inverter. Also, a smaller inverter can be used since tolerances are easier to maintain, lowering the total cost for the system. These small "microinverters" usually cost about $100 - $200 dollars and are guaranteed for 10-15 years. I personally have not included solar panels in my "efficient" home as of yet because of the difficulty in panel placement and the extensive design choices that have to be made when calculating the panel size. One major point I see to these small units is this: a single panel can be added at a time, instead of requiring strings of 8-12 units or more. This alone is an attraction for most people. You simply add panels as money becomes available.

I believe these units are the single biggest advance to come along in solar electric design in a very long time and will greatly influence how quickly panels become commonplace on roofs across the country!