Solar & Battery Regulation & Incentive Programs

Interconnection Standards

Program Overview


Category:
Regulatory Policy
Program Type:
Interconnection
Implementing Sector:
State
State:
Wisconsin
Eligible Storage Technologies:
Geothermal Electric, Solar Thermal Electric, Solar Photovoltaics, Wind (All), Biomass, Hydroelectric, Municipal Solid Waste, Combined Heat & Power, Fuel Cells using Non-Renewable Fuels, Landfill Gas, Wind (Small), Hydroelectric (Small), Anaerobic Digestion, Fuel Cells using Renewable Fuels, Other Distributed Generation Technologies, Microturbines
Website:
http://psc.wi.gov/utilityinfo/electric/distributedGeneration/interconnectionProcedure.htm
Applicable Utilities:
Investor-owned utilities, municipal utilities
System Capacity Limit:
15 MW
Standard Agreement:
Yes
Insurance Requirements:
Vary by system size and/or type; levels established by PSC
External Disconnect Switch:
Required; Varies by system size and utility
Net Metering Required:
No
Applicable Sectors:
Commercial, Industrial, Local Government, Nonprofit, Residential, Schools, State Government, Federal Government, Multifamily Residential, Institutional
Last Updated:
07/20/2015

Eligibility Criteria

EligibilitySectorsTechnologies
max MW15.0000
Commercial
Industrial
Local Government
Nonprofit
Residential
Schools
State Government
Federal Government
Multifamily Residential
Institutional
Geothermal Electric
Solar Thermal Electric
Solar Photovoltaics
Wind (All)
Biomass
Hydroelectric
Municipal Solid Waste
Combined Heat & Power
Fuel Cells using Non-Renewable Fuels
Landfill Gas
Wind (Small)
Hydroelectric (Small)
Anaerobic Digestion
Fuel Cells using Renewable Fuels
Other Distributed Generation Technologies
Microturbines

Summary

In February 2004, the Wisconsin Public Service Commission adopted interconnection standards for distributed generation (DG) systems up to 15 megawatts (MW) in capacity. All investor-owned utilities (IOUs) and municipal utilities are required to abide by the standard provisions. Electric cooperatives are encouraged -- but not required -- to adopt the state standards. The rules categorize DG systems by capacity and provide for several levels of interconnection review, as follows:

  • Category 1: 20 kilowatts (kW) or less
  • Category 2: larger than 20 kW, but no larger than 200 kW
  • Category 3: larger than 200 kW, but no larger than 1 MW
  • Category 4: larger than 1 MW, but no larger than 15 MW

The PSC has published two sets of standard forms for interconnection, available on the program web site. One set pertains to systems smaller than 20 kW while the second set applies to larger systems up the maximum size of 15 MW. The PSC also maintains a list of utility interconnection contacts on their Distributed Generation web site. The Wisconsin Distributed Resources Collaborative (WIDRC) has published a set of interconnection guidelines that offer some additional details on the interconnection process.

Generally speaking, Wisconsin's interconnection requirements become more stringent as the system size increases. The rules apply to all public utilities. The 20-kW dividing line between Category 1 and Category 2 installations corresponds to the maximum individual system capacity allowed under the state's net-metering rules. Systems that qualify for net metering are not considered commercial ventures that require commercial liability insurance.

Minimum liability insurance of at least $300,000 per occurrence is required for systems 20 kW and smaller (Category 1) with higher amounts for larger systems based on the category of review under which they fall. However, the law also permits applicants to prove financial responsibility using a negotiated agreement with the utility in lieu of the insurance requirements. Additionally, Category 2-4 facilities must name the utility as an additional insured party in the insurance policy.

Application and study fees vary by category, but systems 20 kW and smaller are not required to pay any fees for application reviews, engineering reviews, or distribution system studies. Facility owners are permitted to file an appeal with the PSC if they believe they are being held to unreasonable requirements, but the rules provide do not provide any guidance on how such appeals will be addressed. In practice, such an appeal would be addressed as a complaint under s. 196.26, Wis. Stats.


Authorities

NameEnacted DateEffective DateExpired Date
Wis. Stat. § 196.49608/30/2001
Chapter PSC 11902/01/2004