A more efficient microinverter

October 21, 2011 :

The more efficient the microinverter the better, right? One of the most efficient on the market incorporates innovations in power electronics and custom microchips to achieve a 96% weighted CEC efficiency. The M215 from Enphase Energy also includes a 25-year warranty, which is great news for high-performance installations such as commercial solar systems.

One of the biggest issues with inverters is operation and maintenance, but the M215 makes monitoring and analyzing simple with software that displays production information in detail, including graphs, time-lapse videos and energy output by hour, day, week, month and lifetime. The manufacturer’s Enlighten software alerts system owners and installers to any deviation in performance, allowing quick maintenance and increased uptime.

The invert outputs 215 Watts of power with a 22 to 36-Volt MPPT range. In addition to its low-voltage operation capability, the M215 is light weight and installs simply with a single-bolt mounting bracket.

SolarUniverse Inc. recently installed a 180-killowatt system in Livermore, California and used the M215 inverters. “We’re a strong believer in the microinverters for their reliability, high performance and easy installation,” says Michael Flood, director of operations at the company. “We like the system because it›s lightweight, quick to put in and reduces cable waste with its flexible cut-to-length design.”

The company demonstrated the microinverter’s easy of installation by holding a contest at their booth at the Solar Power International show in Dallas Texas October 17-20.  Every hour two contestants installed a system of four mock solar panels with the microinverters and Engage cable working directly across from each other. The overall winner received an iPad 2. Watch them in action and read more on the company’s blog (enphase.com/eblog).

  • ronwint

    You are correct in stating that maintenance is one of the biggest issues with inverters.Unfortunately maintenance of a micro inverter will probably become its undoing. Installing a micro inverter may be quick and easy, but hiring a contractor to remove and re-install several solar modules in order to gain access on a rooftop installation to a failed micro inverter will cost the homeowner up to $500.00 per occurrence. Having 2 or 3 micro inverters fail per year as the micro inverter system ages will get to be expensive in a hurry. And since the micro inverter warranty does not pay for the labor costs involved in removing and replacing products, the homeowner will have to bear this burden. Some micro inverters use electrolytic capacitors in their design. These components are tubular shaped passive devices that store energy. They contain a semi-liquid paste that has a tendency to dry out and fail over time when exposed to extreme temperatures or frequent thermal cycling. This will only enhance a micro inverter’s potential for failure. A much better product is a hybrid design such as SolarEdge which takes the best features of both a central inverter and a micro inverter and combines them in an innovative new product. SolarEdge offers a higher CEC efficiency rating at 97.5% 98.3% peak. It also offers better shade mitigation and a boost in energy harvest of up to 25%. SolarEdge also offers individual solar module monitoring via the Internet and a much higher power handling capacity at up to 300 watts per solar panels so you can use larger solar modules without wasting power on a limited 215 watt inverter rating. Solaredge does not require the addition of an expensive Internet portal or expensive cabling. The cabling and Internet portal are built into SolarEdge at no additional cost. The best part is that SolarEdge cost less than a micro inverter system while offering substantially better performance.