Dive Brief:

• Duke Energy this week reached a settlement with North Carolina solar developers, allowing projects to move ahead and interconnect with the grid while authorizing the utility to disconnect them should grid issues arise.
• The agreement includes more than 30 solar companies; Duke said in recent months some utility-scale projects have been "detrimentally impacting normal distribution system operations and service quality."
• There are currently 3,300 MW of proposed solar projects pending in the state, while Duke owns 500 MW and has purchased another 1,300 MW of renewable power from developers.

​Dive Insight:

North Carolina is a leading state for solar energy in the eastern U.S., but at times that distinction has come with growing pains. In recent months, Duke said it has seen a slate of utility-scale installations hurting the system's ability to provide power to retail load customers, as circuits are overloaded or the intermittent nature of solar causes stability issues.

Now, the utility has worked out an agreement with solar companies allowing their projects to move forward, while giving Duke the authority to disconnect them from the grid should issues arise.

The settlement allows projects that failed a “circuit stiffness review” to move forward, "while providing Duke with power monitoring equipment and clearly-defined rights to disconnect an ADP generator if potential power quality impacts to the Duke system or retail customers caused by that generator occur in the future."

Duke's issues with large amounts of solar connecting to the grid are a familiar problem to utilities in other states as renewable energy grows. In Hawaii, the state's largest utility had put all rooftop solar installations on hold in 2015 citing grid issues, until the state directed Hawaiian Electric to resume connections.

"This could have been a contentious issue. But making North Carolina #3 in the nation for solar power took a lot of compromise by all parties," Duke spokesperson Randy Wheeless wrote in an email statement. "The state is not perfect, and I’m sure there will be disagreements in the future. But right now, the solar record fro Duke Energy and NC looks pretty good."

There are 4,200 net metering customers in North Carolina; Duke has 1,800 MW of solar capacity through projects it owns and capacity it purchases, but there is almost double that amount of capacity currently being developed.