Rules by state

Solar and battery interconnection rules in the District of Columbia

District of Columbia small generator interconnection. Every threshold below was read out of the document linked at the bottom of this page, and the same rules answer the free screening check.

Who this binds: investor owned utilities. A utility outside that list sets its own terms, so confirm who serves the address first.

Check a the District of Columbia address free
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

Level 1 Size 0 to 20 kW

An inverter based facility with a nameplate capacity of 20 kilowatts or less. There is no application fee for a Level 1 request, set by the rule itself rather than by tariff. Screening results follow within five business days, the agreement within three, and authorization to operate within twenty business days of the completed second part.

  • No application fee at Level 1
  • Inverter based equipment
  • Authorization to operate within twenty business days
Level 2 Size 20.001 to 5000 kW

Eligibility depends on the line voltage at the point of common coupling and on location: under 4 kV the limit is 1 MW, rising to 4 MW at 31 to 60 kV, and each band is higher for a facility within two and a half miles of a substation on a main distribution line of at least 600 amps. Results follow within fifteen business days.

  • Fee set in the utility tariff rather than in the rule
  • Line voltage and distance from substation both affect eligibility
Level 3 non export and Level 4 Size 5000.001 to 20000 kW

Level 3 handles a non export facility up to 20 megawatts using reverse power relays, minimum import relays or other protection assuring power can never be exported, and is not available on a spot or area network. Level 4 handles anything not approved at a lower level.

  • Non export protection at Level 3
  • Facilities study at Level 4

The screens that decide it

Ask the utility this, before you sell it

  1. What is this customer historical twelve month usage? The District allows generation up to 200 percent of it, reached by an annual schedule that stepped from 120 percent in 2020 to 200 percent in 2024, measured when a new or amended interconnection application is filed.
  2. What are the Level 2, 3 and 4 application fees? The rule sets only that Level 1 is free and a pre application report costs $300, and puts the rest on the utility website and tariff.
  3. Is the battery in front of the meter and exporting? If so it goes to Level 4 review regardless of size, which no other jurisdiction read does.
  4. Do you have power flow based study results for this line section? Those govern, and the 15 percent figure is only used when they are unavailable.

Worth knowing before you quote

The word insurance does not appear anywhere in Chapter 40, confirmed by searching the full chapter text, so there is no requirement and no prohibition in the interconnection rules. Storage is addressed directly: a non exporting storage device is treated as load based on incremental net load, storage must comply with IEEE 1547, and overcurrent protection ratings from the inverter nameplate may not exceed utility capabilities. Minimum load may be established from actual measured data, from five percent of peak load, or from a customer or utility estimate. The District is one of the few jurisdictions publishing an express authorization to operate deadline.

Source

District of Columbia Municipal Regulations Title 15 Chapter 40, small generator interconnection rules, with net metering at Chapter 9 and D.C. Code Section 34-1518

Read and recorded 2026-09-12. Applicability is written against the facility rather than the utility: the rules apply where total nameplate capacity is 20 megawatts or less, the facility is not subject to PJM interconnection requirements, and it is designed to operate in parallel. There are no municipal or cooperative electric distribution utilities in the District, so the usual ownership question does not arise.

What to do with this

Check a real address

The rules below are the general case. Run the free check to see which utility serves a specific address, which tier the system lands in, and what to ask.

Run the free check
Installers: keep the answer with the job

GridProjeX holds the project from here, with every value tied to the document it came from and the utility and permit tracks run to permission to operate.

How it works for installers
Utilities: see what applicants are told

The same published rules your applicants read here are the ones your queue sees. GridProjeX is the record both sides work from.

How it works for utilities

Also from CivyxIQ, if they fit what you already do: SolarProjeX for running the crews and the jobs, and Solar Home so the homeowner can follow their own project. Neither is needed to use the checker.