Is it worth it to upgrade a solar system to get power from partially obstructed panels?
What you are hearing about are called "micro-inverters". Instead of one large inverter, you have separate, small inverters, one on each panel. I believe you can get them both sepatate and already integrated into panels.

This would require rewiring your PV system, removing the old inverter and installing micros at each panel. as you say, probably not cost effective.