Micro-inverter vs. DC-DC boost

There are two technologies that are garnering both interest and investment in the emerging solar-PV market.

• DC-DC boost - Boosting the DC voltage reduces the transmission losses due to lower current. Power loss is I*I*R. That is a 5% reduction in current leads to 25% reduction in power loss. Also the copper requirement reduces, thus reducing cost. Above all, the target market is existing centralized inverter installations. Besides the BOS cost saving, this technology also increases the total power generated by existing installation by providing per panel MPPT rather than per string optimization. 

• Micro-inverter - Unlike DC-DC boost, the target is new installations. The higher AC voltage makes installation faster and cheaper. And like dc-dc boost, it also reduces the cost of BOS components while providing higher efficiency. 

 There are several new companies in micro-inverter and DC-DC boost segments. However, it is interesting to note that Solar-magic choose to target the existing installations with dc-dc boost. National seems to play it safe given that the micro-inverter market is still nascent. There is third up-coming technology, optimizing per-cell power by making the panel smarter. The cost-benefit analysis is still against this technology, but this might change with new designs and manufacturing processes.