In December 2004, Zapotec Energy was hired as a designer and system integrator to complete a 12.6 kW solar PV system on the roof of MIT building 14, more commonly referred to as the Hayden Library. While Zapotec provided the PV designs, MIT electricians led the installation on the roof of the library as well as other similar systems throughout the MIT campus. The system at Hayden Library is one of four solar PV systems that Zapotec has designed for the Institute.

Last week, the design engineers at Zapotec, including CEO Paul Lyons, helped replace a PV inverter at Hayden Library.  Initially, the engineers noticed its poor production via the SolrenView website, a monitoring system that provides a report of the PV panels’ total energy production. It was obvious that the inverter was no longer functioning at an efficient level. Since the inverter has been connected to the rooftop PV system for 11 years, this came as no surprise to Zapotec. In fact, it was expected.

Typically, an inverter operates for about 10 to 15 years. System owners should expect that their inverter(s) will need to be replaced at least once during the life of a solar PV system, which is about 25 years. At MIT, Zapotec evaluated and diagnosed the inverter before Aldon Electric worked on its replacement and a couple of minor repairs.  The old inverter was replaced with a Fronius inverter and given a 15 year warranty to ensure it will last throughout the system’s remaining years.

“We have been tracking the performance of this PV system for over a decade now,” says Paul Lyons.  “Zapotec will continue to support MIT as they pursue renewable energy.” Overall, the replacement and repair work for the inverter was an easy process.