AC-coupled PV | Parkman

parkman-solar-ac-coupled-solaredge-inverter
INSOURCE RENEWABLES HIRED TO MODERNIZE BATTERY-BASED GRID-TIED SYSTEM

Sam Brown of Parkman has been an early solar adopter on several occasions and contacted Insource Renewables to expand his system and simplify the integration of the expansion with his existing system.

This project was the third stage of Sam’s project. His initial installation was a grid-tied system with battery backup utilizing an Outback charge controller and Outback battery-based inverters. He later expanded his system by installing a second PV array with microinverters that operated independently from the first system.

Insource’s installation of additional capacity involved some unique integration challenges. The PV arrays were located on a separate building than the main barn containing the batteries and inverters. There were two wire runs – one AC and one DC – between the buildings that were elevated, showing signs of distress, and in need of replacement. In addition, there was not a singular approach for expanding the PV capacity based on the systems already in place.

Given Sam’s history as an early adopter and his desire to simplify the system, we presented the option of moving to a DC coupled system. As part of the solution, we installed a new SolarEdge SE6000A-US inverter in the building below the arrays. We added DC optimizers to one of the existing arrays and combined it with the new array to feed the new SolarEdge inverter. We then were able to pull only AC circuits from building-to-building and eliminated the overhead wires.

Sam still wanted the battery backup from his prior system. To achieve this, we replaced his charge controller and battery inverters with an Outback Radian inverter. The use of this inverter allows Sam to island – which means that his system will provide battery backup when the grid is down and be able to run the SolarEdge grid-tied inverter, as well. This unique approach provides high-capacity battery charging from the new array and one of the pre-existing arrays, simplifies the system, and makes the system more adaptable with changing solar policy.

How does it buffer Sam from solar policy changes? The Outback Radian is able to determine the conditions under which to export or import electricity from the grid. With the benefit of batteries, Sam could store energy and export it at times when electricity is in high demand and recharge during times of low demand. As Maine’s energy policy evolves, we hope to see better options to encourage customers to assist the grid when there is significant demand.