NG - National Grid (MA)
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Report a correction Net Metering AllowedYes
NEM TypeMonthly
Supply Side Taps AllowedYes
Line Taps AllowedYes
Load Taps AllowedYes
AC Disconnect RequiredYes
Net metering & export
- Net Metering Allowed
- Yes
- NEM Type
- Monthly
- TOU Utility
- No
- Post Solar Billing Method
- Net Metering
- Solar Export Type
- N/A
- Net Excess Generation Notes
- Excess generation at the end of each month is credited at the applicable retail electricity rate and rolled forward to future bills as a dollar credit. This credit rolls forward indefinitely to future bills but cannot be "cashed out".
- Rebates Offered
- Yes
- Deregulated
- Yes
- Allows Standby
- Yes
Interconnection & taps
- Approval Req To Install
- Yes
- Supply Side Taps Allowed
- Yes
- Line Taps Allowed
- Yes
- Load Taps Allowed
- Yes
- Tap Criteria
- Cannot be in same compartment as utility meter.
- (2) AC disconnects are required. Inv > Non-fused Disco (outside) > Fused Disco (inside, if necessary) > POI
- Automatic Transformer Upgrade Size
- 0
- Meter Aggregation Allowed
- Yes
System size & offset
- System Size Restrictions
- 25
- 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
- Utility Specific Adjustments
Please keep system size under 15 kW AC whenever possible.
For example:
- Please use mix of 7.6KVA and 5.7KVA to be under 15KW AC rather than using two 7.6KVAs. This will avoid Level 2 application and reduce approval times.
Curtailment Requirements
- National Grid allows system curtailment to avoid transformer upgrades and group studies
- Approved curtailment systems: Tesla Gateway, Enphase IQ, and Generac PWRcell
- Update all documents to show the system curtailed to 15 kW AC export
- Add a label showing aggregate AC kW/kVA ratings
- Show both total system size and curtailed system size
- Show internal DB protective device settings for inverters (see Tables 7.6.11.1-1 & 7.6.11.1-2, Page 33 in ESB 756)
- Provide a curtailment letter on manufacturer letterhead if the system is larger than the proposed export, including the model number of the Smart Hub/Gateway and the proposed system output (curtailed value)
- Inverter Oversize Restrictions
- Yes
- System Size Justification
- Load Justification
- System Offset Notes
Metering & disconnect
- Production Meter Required
- Situational
- Production Meter Criteria
Production Meter (SMART meter)
- Required for: Cash, Loan, Aura, Aura+
- Not required for: Lease projects
- Wire inverter on bottom side and utility on top side
- Only 1 production meter per project
- Second meter allowed only if 12 months have passed since existing system PTO
- Production Meter Position
- Inv-Disco-PM-POI
- Production Meter Labeling
- Production Meter
- AC Disconnect Required
- Yes
- AC Disconnect Labeling
- Accessible and Lockable AC Disconnect
- Meter Spot Required
- No
- Allowed Meter Adapter
- None
Plans & docs
- Electric Service Reqs
- Meter relocation is required if the utility meter is located indoors or inside any cabinet
- Single Meter - Center of meter must be between 30 and 60 inches
- Multi Meter - Center of meter must be between 36 and 60 inches
- Placards
- Unit designation labels are required for the meter sockets at the premise (Example; Unit 1, Apt 1, etc)
- Electrical Stamp Required
- Yes
- Equipment Approvals
- Other
- Meter Num Req SLD 3LD
- No
- ESID Num Req SLD 3LD
- No
- Site Plan Notes
- Label Page Notes
- Cover Page Notes
- Electrical Diagram Notes
Battery [STORAGE CHARGING CAPABILITY: GENERATION ONLY STORAGE DISCHARGING CHARACTERISTICS: ON-SITE LOAD ONLY]
- Website
- link
- Phone
- (800) 322-3223
Other details
- Revision Required
- Yes
- Mod Swap Requires Planset
- Yes