Net metering measures the difference between the electricity supplied over the electric distribution system (by your utility company) and the electricity generated by an eligible on-site generator and fed back into the distribution system. The meter registers the flow of electricity in both directions, and only the net amount is billed (or credited) each month.
By installing an on-site generator, you may be able to reduce the amount of energy purchased from your energy supplier (typically your utility company) and receive compensation for excess energy (exported energy to the grid) produced by your on-site generator. This credit can be applied later to your future kWh usage.
In months when the on-site generator produces more energy than is consumed, the customer will be billed for zero energy and the excess energy is "banked" as an offset to energy consumed in future months. If the excess amount banked exceeds 600 kWh at the end of the March billing cycle each year, the customer will have the option to continue to bank the kWh towards future months or may elect to receive the economic value of the surplus kWh as a bill credit or one-time payment
. The economic value of the surplus kWh will be determined in accordance with the NHPUC 900 rules
As defined in RSA 362-A:1, II-b per the New Hampshire Public Utilities Commission, an eligible customer is an electric utility customer who fulfills one or more of the following:
Owns or operates an electrical generating facility (on-site generator) powered by renewable energy that has a capacity of not more than 1,000 kilowatts
Owns and operates a heat-led combined heat and power system (on-site generator) that has a capacity of 100 kilowatts or more but less than or equal to 1,000 kilowatts, which began operating after July 1, 2010
Owns or operates a heat-led combined heat and power system (on-site generator), with a total peak generating capacity of not more than 100 kilowatts that was installed on or before July 1, 2010
The on-site generator:
Is located behind a retail meter on the customer's premises
Is interconnected and operates in parallel with the electric grid
Is primarily used to offset the customer's own electricity requirements
Application Process for Interconnection and Net Metering
100 kW or Less Capacity Systems
For customers wishing to install systems of 100 kW or less, please fill out and submit the state-wide Simplified Process Application that is included in Unitil’s 100 kVA Interconnect Standards.
More than 100 kW Capacity Systems
For customers wishing to install systems greater than 100 kW, apply for interconnection and Net Metering using the Expedited/Standard Process. Please contact the Company for more information.
Other Useful Links:
(PUC Rule 900) - rules and technical requirements for net metering set forth by the New Hampshire Public Utilities Commission
Notice to Customers Interested in Net Metering
The Commonwealth of Massachusetts requires each electric utility to provide net metering to customers with qualifying generation systems. There is, however, a limitation on the amount of generation that is eligible to be net metered on each electric utility’s system. This is known as the statutory “cap” on net metering capacity. Each electric utility, including Unitil, is required to limit the combined generation capacity of all non-exempt net metering facilities to 3% of the utility’s historic peak load for non-municipal (“Private”) customers and 3% of the historic peak for municipal (“Public”) customers. Accordingly, for Unitil, the maximum amount of non-municipal generation eligible for net metering (Unitil’s Private cap) is 3.06 MW. The maximum amount of municipal generation eligible for net metering (Unitil’s Public cap) is 3.06 MW. Unitil is required by law to limit the net metering capacity in accordance with these caps. See, G.L. c. 164 s. 139. Systems that are a Class I renewable energy generating facility and have a nameplate rating less than or equal to 10 kW on a single phase circuit or 25 kW on a three phase circuit are exempt from the Private Cap.
The final determination of eligibility for net metering is made after it is installed and at the time the generation system has had its final inspection and commissioning test and is issued the Approval to Interconnect by Unitil. As a result, net metering may not be available to some applicants who request it, even if they have an approval to install the generation facility. In the event that the net metering cap has been fully subscribed, interconnection of customer generation to Unitil’s electric distribution system is still allowed, but not under the Net Metering Tariff, and Net Metering Credits would not be available for any of the excess electricity generated by the customer’s facility.
Please see the chart
at the bottom of this page for more information regarding the status of capacity remaining in regards to the private and municipal caps. We hope that this information is helpful. Should you have any questions please feel free to call our office at 888-301-7700
. We look forward to working with you.
The Massachusetts Department of Public Utilities approved Unitil's Net Metering Tariff
, effective July 9, 2012. The Green Communities Act provides for three classes of net metering customers:
Class 1: Solar/wind/agricultural generation, 60 kW and less
All other generation (non-renewable) 60 kW and less
Class 2: Solar/wind/agricultural generation over 60 kW to 1,000 kW
Class 3: Solar/wind/agricultural generation over 1,000 kW to 2,000 kW
Municipal or Government Entities
A customer wishing to be certified as a municipal or other governmental entity MUST be certified by the D.P.U. as such before the company can provide net metering service or allocate credits under the public net metering cap. Please complete the government application below and submit to the D.P.U. and the Company.
In addition to the Interconnection Application, an eligible customer must complete and submit Schedule Z in order to be considered for Net Metering.
System of Assurance
In order to guarantee a position under the net metering Caps, all non Cap exempt Customers must apply for allocation under the Massachusetts System of Assurance for Net Metering.
Other Important Net Metering Information
Under the net metering rules, customers that are net exporters of power for the month will receive a credit on their monthly bill based on the following formula:
Class 1 and 2 customers and municipal/governmental Class 3 customers whose generation is wind, solar, anaerobic digestion or agricultural will receive credit equal to the excess kilowatt-hours (kWh) by time-of-use rates, if applicable, and the product of the sum of the following charges applicable to the rate class under which the customer takes service:
Basic service kWh charge
Distribution kWh charge
Transmission kWh charge
Transition kWh charge
Other Class 3 customers will receive credit equal to the excess kilowatt-hours (kWh) by time-of-use rates, if applicable, and the product of the sum of the following charges applicable to the rate class under which the customer takes service:
Basic service kWh charge
Transmission kWh charge
Transition kWh charge
Class 1 customers whose generation is not solar, wind, anaerobic digestion or agricultural will continue to receive the average loss-adjusted monthly clearing price set by ISO New England.
|Historical Peak Load:||102 MW (July 27, 2005)|
|Private Cap Exempt Customers as of June 2013||0.73 MW*|
| || |
|Non-Municipal Customers|| |
|Net Metering Cap (Private):||3.06 MW (3% of historical peak load)|
|Net Metering Online as of June 2013:||1.55 MW*|
|Amount Remaining:||1.51 MW*|
|Completed Applications Pending:||0 MW*|
| || |
|Municipal Customers & Other Government Entities|| |
|Net Metering Cap (Public):||3.06 MW (3% of historical peak load)|
|Net Metering Online as of June 2013:||0.31 MW*|
|Amount Remaining:||2.75 MW*|
|Completed Applications Pending:||2.35 MW*|
*Calculated using 80% estimated DC rating for solar pv.