How is system size measured for interconnection in North Carolina?

The published limits are stated in kilowatts without saying whether that is the inverter alternating current rating or the array direct current rating.

What does 20 kW inverter process mean in North Carolina?

A certified inverter based facility no larger than 20 kW. The processing fee is $200 and is non refundable. For a residential system at or below 250 kW the insurance requirement is a standard homeowner policy with at least $100,000 per occurrence. Review completes in 15 business days.

What does Fast track, above 20 kW to 100 kW mean in North Carolina?

The fee is $750 and a supplemental review deposit of $750 applies. Non residential insurance at or below 250 kW is at least $300,000 per occurrence.

Is the nameplate capacity measured in alternating or direct current? The procedures define it only as the manufacturer rated output capability, where the South Carolina equivalent says alternating current outright.

Only the utility holds this figure. Ask before you quote the job.

What is the line voltage at this address, and is the site on a mainline within 2.5 electrical circuit miles of a substation? Fast track eligibility depends on both.

Only the utility holds this figure. Ask before you quote the job.

North Carolina solar interconnection rules, tiers and fees

How the size is measured: not published

The published limits here are stated in kilowatts without saying whether that is the inverter rating in alternating current or the array rating in direct current. On a system near a threshold that decides which band it lands in, so the checker asks the question rather than choosing an answer.

Size bands and what each one obliges

20 kW inverter process Size 0 to 20 kW	A certified inverter based facility no larger than 20 kW. The processing fee is $200 and is non refundable. For a residential system at or below 250 kW the insurance requirement is a standard homeowner policy with at least $100,000 per occurrence. Review completes in 15 business days. $200 non refundable processing fee Standard homeowner policy of at least $100,000 per occurrence for residential
Fast track, above 20 kW to 100 kW Size 20.001 to 100 kW	The fee is $750 and a supplemental review deposit of $750 applies. Non residential insurance at or below 250 kW is at least $300,000 per occurrence. $750 application fee $750 supplemental review deposit $300,000 per occurrence for non residential
Fast track, above 100 kW to 2 MW Size 100.001 to 2000 kW	The fee is $1,000 with a $1,000 supplemental review deposit. Above 250 kW the non residential insurance requirement rises to at least $1,000,000 per occurrence. Initial review runs 20 business days. $1,000 application fee $1,000 supplemental review deposit $1,000,000 per occurrence above 250 kW
Study process, above 2 MW Size 2000.001 kW and above	All facilities larger than 2 MW use the study process. The deposit is $20,000 plus $1 per kW AC below 20 MW, $35,000 plus $1 per kW AC between 20 and 50 MW, and $50,000 plus $1 per kW AC above 50 MW. $20,000 plus $1 per kW AC study deposit, rising with size $1,000,000 per occurrence insurance

The screens that decide it

Below the 2 MW fast track ceiling Limit 2000 kW.
Fast track eligibility also depends on line voltage: 100 kW below 5 kV rising to 2 MW from 15 to 35 kV, with a higher band on a mainline within 2.5 electrical circuit miles of a substation. Facilities on lines of 35 kV or more are ineligible for fast track regardless of size unless mutually agreed in writing.
Within the 20 kW AC residential net metering limit Limit 20 kW.
Residential net metering is limited to 20 kW AC and non residential to 1 MW AC. Above those the interconnection right survives but the rider does not.
Aggregate generation under 65 percent of the shared secondary transformer rating 65 percent of service transformer rating, a figure only the utility holds.
North Carolina uses 65 percent of the transformer nameplate rating on a single phase shared secondary.
Aggregate generation under 15 percent of line section annual peak load 15 percent of line section peak load, a figure only the utility holds.
North Carolina applies the classic 15 percent line section screen measured at the substation, and adds a screen the neighboring states lack: aggregate generation may not exceed 90 percent of the circuit or bank minimum load at the substation.
Aggregate generation under 90 percent of circuit minimum load 90 percent of line section minimum load, a figure only the utility holds.
This screen is specific to North Carolina and is not in the South Carolina version of the same document family.

Ask the utility this, before you sell it

Is the nameplate capacity measured in alternating or direct current? The procedures define it only as the manufacturer rated output capability, where the South Carolina equivalent says alternating current outright.
What is the line voltage at this address, and is the site on a mainline within 2.5 electrical circuit miles of a substation? Fast track eligibility depends on both.
Is this address served by a rural electric cooperative or a municipal utility? Neither is required to offer net metering and neither is covered by these procedures.
Which net metering rider applies? The legacy rider closed to applications on 30 September 2023 and existing customers ride it only to 31 December 2026.

Worth knowing before you quote

North Carolina publishes no aggregate net metering capacity cap. What closed was rider enrollment, not a capacity cap, so a screening tool should not carry a cap filled flag for this state. Adding direct current optimizers, converters, charge controllers, plant controllers or storage devices is not a material modification where it does not change the maximum generating capacity, the daily production profile or the proposed alternating current configuration.

Utility programs we have read in North Carolina

Source

North Carolina Interconnection Procedures, Forms and Agreements for state jurisdictional generator interconnections, effective 1 November 2025, North Carolina Utilities Commission Docket E-100 Sub 101

Read and recorded 2026-09-12. A single statewide document administered by the Commission jurisdictional utilities, Duke Energy Carolinas, Duke Energy Progress and Dominion Energy North Carolina. Rural electric cooperatives and municipal electric utilities are not required to offer net metering and are outside these procedures.

Solar and battery interconnection rules in North Carolina

Size bands and what each one obliges

The screens that decide it

Ask the utility this, before you sell it

Worth knowing before you quote

Utility programs we have read in North Carolina

What to do with this