Net metering was originally authorized for renewable-energy systems and combined-heat-and-power (CHP) facilities with a generating capacity up to 30 kilowatts (kW) by the Massachusetts Department of Public Utilities in 1982. In 1997, the maximum individual system capacity was raised to 60 kW and customers were permitted to carry any net excess generation (NEG) — credited at the "average monthly market price of generation" — to the next bill.
In July 2008, net metering was significantly expanded by S.B. 2768, which established three separate categories of net-metering facilities. "Class I" facilities are generally defined as systems up to 60 kW in capacity. "Class II" facilities are generally defined as systems greater than 60 kW and up to one megawatt (MW) in capacity that generate electricity from agricultural products, solar energy or wind energy. "Class III” facilities are generally defined as systems greater than 1 MW and up to 2 MW in capacity that generate electricity from agricultural products, solar energy or wind energy.
Massachusetts also allows “neighborhood net metering” for neighborhood-based Class I, II or III facilities that are owned by (or serve the energy needs of) a group of 10 or more residential customers in a single neighborhood and served by a single utility.
Nevada’s original net-metering law for renewable-energy systems was enacted in 1997 and amended many times. Systems up to one megawatt (MW) in capacity that generate electricity using solar, wind, geothermal, biomass and certain types of hydropower are generally eligible, although systems greater than 100 kilowatts (kW) in capacity may be subject to certain costs at the utility’s discretion. Systems must be designed to offset part or all of a customer-generator’s electricity requirements. A system is not eligible for net metering if its generating capacity exceeds the greater of (1) the limit on demand that the class of customer of the customer-generator may place on the utility’s system, or (2) 150% of the customer’s peak demand. Each investor-owned utility operating in Nevada must offer net metering until the aggregate capacity of all net-metered systems in its service territory equals 1% of the utility’s peak capacity.
For net-metered systems up to 100 kW, utilities must offer the customer-generator a meter capable of registering the flow of electricity in two directions. The utility may not charge these customer-generators any fee that would increase their minimum monthly charges to an amount greater than that of other customers in the same rate class. Excess electricity generation can be carried forward indefinitely on the customer’s bill to offset electricity use. NEG can be counted by the utility toward renewable energy portfolio standard requirements.
Thereare different rules for systems above 30 kW and systems sized larger than 30 kW will not have as attractive terms economically speaking. Utilities must offer net metering for eligible systems until the cumulative capacity of all such net metering systems is equal to 1 percent of the utility’s peak capacity.
View Nevada’s Net Metering Statute
Nevada Revised Statutes 704.766 to 704.775
New York’s original net metering law was signed into law on August 13, 1997. The law has been amended several times since. In 2008, the net metering rules were changed for the state’s investor owned utilities. Project can be developed on a first-come, first-served basis until overall system limits are reached. The aggregate limit on net-metered PV and on-farm biogas systems combined is set at 1.0% of a utility’s 2005 electric demand, while the limit on aggregate wind system capacity is 0.3% of 2005 demand.
- Solar: 25 kW for residential, 2 MW or peak load for non-residential;
- Wind: 25 kW for residential, 500 kW for farm-based, and 2 MW or peak load for non-residential;
- Biogas: 500 kW (farm-based only)
In January 2009, the municipally-owned utility, Long Island Power Authority (LIPA), made effective changes to its net metering policy. LIPA’s net metering rules are generally consistent to the terms offered under the NY state net metering law, although unlike the state, LIPA does not offer net metering to farm-based anaerobic digester systems.
Underthe most recent revisions, net metering is available for residential, non-residential, and farm-service PV and wind systems subject to the following system capacity limits:
- Residential: Solar, wind, or hybrid systems up to 27.5 kW.
- Farm-Service: Solar systems up to 27.5 kW and wind systems up to 500 kW. Hybrid systems are subject to the 500 kW cap.
- Non-residential: Solar, wind, and hybrid systems are eligible. Non-residential customers with a peak demand of 25 kW or less during the preceding 12 months may net meter systems up to 110% of their peak billing demand. Non-residential customers with a peak demand of 25 kW to 27.5 kW during the preceding 12 months may net meter systems up to 27.5 kW. Non residential customers with a peak billing demand of greater than 27.5 kW during the preceding 12 months are limited to systems sized at 100% of their peak demand, not to exceed 2 MW.
Netmetering will be made available until overall solar enrollment reaches 51.2 MW (1% of 2005 peak electric demand) and overall wind enrollment reaches 15.3 MW (0.3% of 2005 peak electric demand). Net metering is accomplished using a single-bidirectional meter. Net excess generation (NEG) is carried forward from month to month at the customer’s retail electricity rate. Excess NEG left over at the end of a 12-month period is purchased by LIPA at the seasonal(winter/summer) avoided cost rates.
The Oregon Public Utilities Commission (PUC) adopted new rules for net metering for PGE and PacifiCorp customers in July 2007, raising the individual system limit from 25 kilowatts (kW) to two megawatts (MW)for nonresidential applications. The limit on individual residential systems is 25 kW. Systems that generate electricity using solar power, wind power, hydropower, fuel cells or biomass resources are eligible. Net-metered systems must be intended primarily to offset part or all of a customer’s requirements for electricity. Utilities may not limit the aggregate capacity of net-metered systems.
Net excess generation (NEG) is carried over to the customer’s next bill as a kilowatt-hour credit for a 12-month period. Any NEG remaining at the end of a 12-month period will be credited at the utility’s avoided-cost rate to customers enrolled in Oregon’s low-income assistance programs. Customers retain ownership of all renewable-energy credits (RECs) associated with the generation of electricity. The aggregation of meters for net metering is permitted.
Oregon’s municipal utilities, electric cooperatives and people’s utility districts must offer customers net metering and systems that generate electricity using solar power, wind power, hydropower, fuel cells or biomass resources are eligible. The aggregated capacity of all net-metered systems is limited to 0.5% of a utility’s historic single-hour peak load.
Passed in early 1998, Vermont’s original net metering law was interesting in that it established a new class of electric generation qualifying for net metering called the farm system. A farm system was one that generated energy from the anaerobic digestion of agricultural products or byproducts, solar-electric (PV) systems, wind systems or fuel cells may net meter systems up to 150 kW (non-farm generators had to be less than 15kW to qualify for net metering).
Vermont’s original law was modified several times including in 2008. Any electric customer in Vermont may net meter after obtaining a Certificate of Public Good from the Vermont Public Service Board (PSB).
Netmetering is generally available to systems up to 250 kilowatts (kW) in capacity that generate electricity using eligible renewable-energy resources, and to micro-combined heat and power (CHP) systems up to 20 kW. “Renewable energy” is defined as “energy produced using a technology that relies on a resource that is being consumed at a harvest rate at or below its natural regeneration rate.” Biogas from sewage-treatment plants and landfills, and anaerobic digestion of agricultural products, byproducts and wastes are explicitly included.(The term "renewable energy" explicitly excludes solid waste that is not agricultural or silvicultural, as well as nuclear fuel, coal, oil, propane and natural gas.)
Vermonthas established special provisions to allow “group net metering” and net metering for farm-based renewable-energy systems.
Net metering is available on a first-come, first-served basis until the cumulative capacity of net-metered systems equals 2% of a utility’s peak demand during 1996 or the peak demand during the most recent full calendar year, whichever is greater.
Note that Green Mountain Power, an investor-owned electric utility operating in Vermont, offers a bonus payment to customers with net-metered photovoltaic (PV) systems. In addition to the benefits of net metering, Green Mountain Power customers with a PV system receive a payment of $0.06 per kilowatt-hour (kWh) of electricity generated by the system. This payment is available to all customers of Green Mountain Power, which serves roughly one-quarter of Vermont’s population. This program, known as Solar GMP, took effect in July 2008.
- View Vermont’s Net Metering Statute – Title 30 V.S.A. §219a
- Vermont’s Department of Public Service has a section on Net Metering in Vermont
- Vermont Public Service Board’s Rules covering net metering
New Rules thanks the good people at DSIRE for much of the information in the descriptions above and who do a great job tracking these developments across the country.