Key Cargo Hybrid System

In 2018, Greentech Renewables provided engineering and procurement services for a 625 kW hybrid system for Key Cargo in Jacksonville, Florida. The system included equipment from JinkoSolar, SolarEdge, Chilicon, and Ecolibrium. The site includes a 200 kW generator on-site that ties into the Chilicon portion of the array to provide emergency backup for critical loads.

The project was located at an industrial distribution facility. Power resiliency was paramount for the customer. As such, they wanted to add both solar plus the ability to backup large, critical loads on site. The project was unique because the customer requested that part of the solar system operate in parallel with the backup generator during grid outages. Most solar systems installed on site with backup generators are interconnected in such a way as not operate during an outage condition. In fact, very few inverters in the market are capable to run in parallel with an on-site backup generator.

To meet this challenge, the project was designed with the two different inverter types and interconnected at two separate points behind the same meter. A 121 kW PV system with Chilicon microinverters was interconnected along with a backup generator downstream of an Automatic Transfer Switch. Critical loads for the facility were also moved into this new protected panelboard. The Chilicon microinverters operate like a normal grid-tied inverter when the grid is active. During an outage, the chilicon inverters sense voltage/frequency from the backup generator and resume generating. Chilicon offers an advanced Volt-Watt mode grid support functionality, which enables the inverters to operate in this microgrid without the risk of causing an over-voltage condition which arises when generation is not matched to load. Voltage is constantly monitored by each inverter and the inverters linearly derates power between preset start and stop voltage thresholds.

The second component of the project consisted of a 500 kW PV system with SolarEdge 33.3kUS inverters which is interconnected on the utility side of Automatic Transfer switch and shuts off like normal during a grid outage.