Northwestern Corporation

Montana Utility Interconnection & net metering rules

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Net Metering AllowedYes

NEM TypeAnnual

Line Taps AllowedYes

Load Taps AllowedYes

MPU Rules<p>If MPU is required, Northwestern Energy requires it to be

AC Disconnect RequiredYes

Net metering & export

Net Metering Allowed: Yes

NEM Type: Annual

TOU Utility: No

Post Solar Billing Method: Net Metering

Net Excess Generation Notes: If during the monthly billing period the electricity generated by the consumer is greater than what was consumed, the excess kWhs shall be carried into subsequent billing periods, until the consumption offsets the excess kWh balance or the time of the annual true up at the end of the designated 12 month billing period, which ever is earlier. At the annual true up, any excess kWh balance remaining will be granted to the utility with no compensation to the customer.

Rebates Offered: No

Deregulated: Yes

Allows Standby: Yes

Interconnection & taps

Approval Req To Install: Yes

Line Taps Allowed: Yes

Load Taps Allowed: Yes

MPU Rules: If MPU is required, Northwestern Energy requires it to be a minimum 200A Upgrade. This requirement is only when we are upgrading.

Automatic Transformer Upgrade Size: 0

Meter Aggregation Allowed: No

System size & offset

System Size Restrictions: 50

System Size Restriction Type: AC kW

System Size Battery Included: No

System Size Includes Existing Systems: No

Offset Type: No Restrictions

Offset Value: 0

Offset Calculation Period: 0

Industry Standard Watts Sqft: 2

System Offset Notes

Up to 50 kW AC

NOTE:

-At the annual true up, any excess kWh balance remaining will be granted to the utility with no compensation to the customer.

Offset Calc Tool: Historical Usage

Metering & disconnect

Production Meter Required: No

Production Meter Criteria: PM socket is optional if the customer wants it. It is not a utility requirement. Please

Production Meter Position: N/A

Production Meter Labeling: N/A

AC Disconnect Required: Yes

AC Disconnect Labeling: Visible Lockable Labeled Disconnect

Allowed Meter Adapter: None

Plans & docs

Site Plan Reqs

Standard - Must show distance between AC Disconnect and utility meter, if equipment is not grouped together. If grouped together a note stating equipment within 10' is adequate.

AC Disconnect Required

External, visible and lockable disconnect within 10 feet of the utility meter
If the AC Disconnect is not within 10 feet of the utility meter, the utility must approve the location prior to installation, which may require a utility site visit.
If seeking a variance from the 10 foot requirement, the installer must show the proposed location of the AC disconnect in the detailed site diagram, and include an explanation justifying the need to locate the AC disconnect more than 10 feet from the meter (including physical limitations).

SLD Reqs: Standard - Must show distance between AC Disconnect and utility meter

Electric Service Reqs

Install Reqs: Northwestern energy will not allow us to install on split structures IF the home has 2 or more meters - If it has 2 or more meters, the panels MUST be on the structure the meter we are offsetting is on. For example, if the home has 2 meters, one of the detached garage one on the main home, and the customer wants the panels on the garage but we are offsetting the main home meter, they will not allow this. Please message staff if you have any questions

Electrical Stamp Required: No

Equipment Approvals: California Energy Commission

Meter Num Req SLD 3LD: No

ESID Num Req SLD 3LD: No

Site Plan Notes

Cover Page Notes: remove Utility Meter number from all pages. (delete)

Website: link

Phone: (406) 497-4165

Other details

Revision Required: Yes

Mod Swap Requires Planset: Yes