Rules by state

Solar and battery interconnection rules in Wisconsin

Wisconsin distributed generation interconnection (PSC 119). 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, municipal utilities.

Check a Wisconsin address free
How the size is measured

export capacity in kilowatts alternating current: the lesser of the nameplate rating or, where limited by approved means, that limited amount. Nameplate rating is the sum total of maximum continuous rated power output while grid connected of all generating units and energy storage systems as identified on the manufacturer nameplate, regardless of limiting. Critically, the nameplate rating replaces export capacity for tier placement whenever a non exporting storage system is larger than the tier threshold.

Size bands and what each one obliges

Category 1 Size 0 to 20 kW

An export capacity of 20 kW or less, including a resource no larger than 20 kW paired with a non exporting storage system no larger than 20 kW. The application review fee is $150 from one to eight kilowatts and $300 from nine to twenty, with a $150 commissioning fee. Wisconsin requires $300,000 of liability insurance even at this size, the only state in the region to require it on a small residential system.

  • $150 or $300 application review fee by size
  • $150 commissioning fee
  • $300,000 minimum liability insurance
Category 2 Size 20.001 to 200 kW

Greater than 20 kW and not more than 200 kW. The nameplate rating is used instead of export capacity where a non exporting storage system is larger than 20 kW. The fee is $300 plus $10 per kW, the steepest per kilowatt application fee in the region, plus a $250 commissioning fee. Insurance is $1,000,000 and the utility must be named an additional insured.

  • $300 plus $10 per kW application review fee
  • $250 commissioning fee
  • $1,000,000 insurance naming the utility as additional insured
Category 3 Size 200.001 to 1000 kW

Greater than 200 kW and not more than 1 MW, with the same nameplate substitution where non exporting storage exceeds 200 kW. The fee is $2,000 plus $2 per kW with a $1,000 commissioning fee, and insurance is $2,000,000.

  • $2,000 plus $2 per kW
  • $1,000 commissioning fee
  • $2,000,000 insurance naming the utility as additional insured
Category 4 Size 1000.001 to 15000 kW

Greater than 1 MW and not more than 15 MW. The fee is $4,000 plus $0.50 per kW with a $2,500 commissioning fee, and the insurance amount is negotiated.

  • $4,000 plus $0.50 per kW
  • $2,500 commissioning fee
  • Negotiated insurance

The screens that decide it

Ask the utility this, before you sell it

  1. How large is the non exporting battery on this job? In Wisconsin a storage system larger than the tier threshold switches the measurement from export capacity to full nameplate rating, so a nineteen kilowatt array with a thirty kilowatt battery is not a Category 1 system and pays a Category 2 fee.
  2. Will you waive the application fees? The rule allows a utility to waive them in whole or in part.
  3. What net metering does your tariff offer, and at what size limit? Wisconsin publishes no statewide net metering rule; it lives in each approved utility tariff and is commonly capped at twenty kilowatts.
  4. Is this address served by an electric cooperative? Cooperatives serving members only are expressly excluded from PSC 119.

Worth knowing before you quote

Wisconsin is the only state in the region requiring liability insurance on a twenty kilowatt residential system, at $300,000, and Categories 2 and above must name the utility as an additional insured or prove financial responsibility another way. Application completeness and application review are each ten working days, and where no engineering review is needed the applicant may simply install. Engineering review runs from ten working days at Category 1 to forty at Category 4 and a distribution system study from ten to sixty. Wisconsin publishes no aggregate program cap. Whether PSC 119 contains a fifteen percent screen could not be determined, because the design requirement sections were not read in full; no such figure appears in the sections that were.

Utility programs we have read in Wisconsin

Source

Wisconsin Administrative Code Chapter PSC 119, rules for interconnecting distributed generation facilities, implementing Wisconsin Statutes Section 196.496

Read and recorded 2026-09-12. Establishes uniform statewide standards and binds public utilities, which in Wisconsin includes municipal electric utilities because a town, village or city operating a plant is a public utility under the statute. Electric cooperatives organized to serve their members only are expressly excluded and are not bound. Wisconsin publishes no statewide net metering rule; net metering exists in individual approved utility tariffs.

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.