As we’ve discussed in the past on this blog, there are a number of ways in which the US solar market is changing- declining panel prices, volatile state SREC markets, and innovative incentive programs are just a few examples. However, a recent announcement from REFU Solar Electronics, or REFUsol, a German manufacturer that specializes in solar inverter technology, underlines what could be the next major shift in the US solar industry.
Upon receiving approval from Underwriters Laboratories, a public safety non-profit organization whose certification is globally respected, REFUsol has indicated their plans to aggressively expand into the US solar market. With plans to establish a presence in the Bay Area, Los Angeles, Colorado, Chicago, Dallas, New Jersey, and South Carolina, REFUsol cited the growing demand for solar in the US as the impetus for their new strategy.
Just as Chinese panel production has made solar more affordable in the US, so too can increased competition in inverter technology from reputable firms like REFUsol. Though they are not debated as hotly as panel manufacturing or rebate programs, inverters can have a huge impact on the long-term economics of installing a solar energy system, due to its role in determining a system’s productivity and lifespan. First, the efficiency of the inverters measures how much direct current electricity (DC) created by the panels is converted into alternating current (AC), the latter of which is sent to electricity consumption devices. The average efficiency of an inverter is about 94% (REFUsol has inverters with peak efficiencies of 97-98%).
Second, the type of inverter is equally important. Micro-inverters are increasing in popularity as opposed to central and string inverters. The main difference is that micro-inverters line up (usually) one-to-one with individual panels, rather than having all the panels in the system route through one inverter. This has a couple advantages. If a system is partially in the shade, or has a defective panel, the overall production will not be hindered as greatly (or entirely, in the case of string inverters). More importantly, the lower producing panel can be identified more easily. Another advantage to micro-inverter technology is that they allow for the possibility of expanding a solar energy system without significantly re-wiring the electrical circuits. Micro-inverters are an attractive option for residential solar because individual panel productivity is crucial to the affordability of the system; the marginal affect of one failing panel is much greater, so identifying and mitigating those defects is of utmost importance.
We’ll keep an eye out for significant updates and market developments in the world of solar inverters- stay tuned!