Solar Thermal Electric

Interconnection Standards

Note: The California Public Utilities Commission (CPUC) has an ongoing interconnection rule revision docket (Rulemaking (R.) 17-07-007) that has made many revisions to interconnection rules since July 13, 2017. Current interconnection rules for each utility are available at the CPUC website.

California's "Rule 21" generally applies to systems connecting to an investor-owned utility’s distribution grid, non-export generating facilities connecting to an investor-owned utility’s transmission grid and all net metered facilities in an investor-owned utility’s service territory. Systems connecting to an investor-owned utility’s distribution grid for the purpose of participating in a wholesale transaction must apply under the investor-owned utility’s Wholesale

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Interconnection Guidelines

Note: S.B. 295 was signed in March 2023, and changes related to interconnection were approved by the Public Service Commission in late September 2023 via Order No. 7 in Docket No. 23-021-R.

In April 2001, Arkansas enacted legislation directing the Arkansas Public Service Commission (PSC) to establish net-metering rules for certain renewable-energy systems. The Arkansas Public Service Commission (PSC) adopted net-metering rules in July 2002 (Docket No. 02-046-R, Order No. 4), which include interconnection requirements for net metering facilities interconnect to existing electric power systems (Section 3).* Systems that generate electricity using solar, wind, hydro, geothermal and biomass

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Net Billing

Eligibility and Availability

Utah’s net metering policy, adopted in 2002, applies to all electric investor-owned utilities and electric cooperatives. Systems up to 25 kW in capacity for residential and up to 2 MW for non-residential that generate electricity using solar, wind, hydrogen, organic waste, hydroelectric, waste gas and waste heat capture/recovery, certain biomass and woody debris, agricultural residues, dedicated energy crops, landfill or biogas, or geothermal are eligible. Enrollment is limited to 0.1% of the corporation’s peak demand during 2007 (this limit may be increased by the corporation’s governing authority). 

Net Excess Generation

Net excess generation (NEG) is credited to

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Renewable Energy Trust Fund

Massachusetts Public Benefit Funds

Massachusetts's 1997 electric utility restructuring legislation created two separate public benefit funds to promote renewable energy and energy efficiency for all customer classes.

Funding and Administration

The Massachusetts Renewable Energy Trust Fund is supported by a non-bypassable systems benefits charge of $0.0005 per kilowatt-hour (0.5 mill/kWh), imposed on customers of all investor-owned electric utilities and competitive municipal utilities in Massachusetts. (Non-competitive municipal utilities generally may opt into the Fund by agreeing to the same provisions that apply to investor-owned utilities and competitive municipal utilities.) 

The Massachusetts Clean Energy Center, a quasi-public research and development entity, administers

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Renewable Portfolio Standard

In March 2004, New Mexico’s governor signed into law the Renewable Energy Act (S.B. 43 (2024)), creating a state renewable portfolio standard (RPS). By 2020, investor-owned utilities (IOUs) are required to generate 20% of total retail sales from renewable energy resources, and rural electric cooperatives are required to generate 10% of total retail sales from renewable energy resources. This requirement was later increased by S.B. 489 (2019).

Eligible Technologies

Renewable energy is defined as electric energy generated by low- or zero-emissions generation technology with substantial long-term production potential; solar; wind; geothermal; hydropower facilities brought in service after

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System Benefits Charge

New York's system benefits charge (SBC), established in 1996 by the New York Public Service Commission (PSC), supports energy efficiency, education and outreach, research and development, and low-income energy assistance. To support the SBC program, the state's six investor-owned electric utilities collect funds from customers through a surcharge on customers' bills. The SBC program is administered by NYSERDA and funds numerous programs to improve the state's transmission and distribution infrastructure. The program goals include improving system-wide reliability and increasing peak-electricity reductions through end-user efficiency actions; improving energy efficiency and access to energy options for under-served customers; reducing the environmental impacts

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West Penn Power SEF Commercial Loan Program

WPPSEF Offers Conventional Financing that ranges from $25,000 to $1,000,000 and ACT 129 Micro Loans that range from $10,000 to $50,000. For more information on these programs please visit the website above.

The West Penn Power Sustainable Energy Fund (WPPSEF) promotes the use of renewable energy and clean energy among commercial, industrial, institutional and residential customers in the West Penn market region. Eligible technologies include solar, wind, low-impact hydro, sustainable biomass such as closed-loop biomass and biomass gasification, and innovative natural gas technologies as well as energy efficiency. Clean energy refers to advanced technologies, including landfill gas and fuel cells

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Met-Ed / Penelec Sustainable Energy Fund

FirstEnergy (formerly GPU) established the Metropolitan Edison Company (Met-Ed) Sustainable Energy Fund in 2000 with an initial contribution of $5.7 million. The fund later received an additional contribution of $2.5 million as a result of the merger between GPU Energy and FirstEnergy, bringing the total to $8.2 million. The fund is administered by the Berks County Community Foundation. The majority of funding available from the Metropolitan Edison Company SEF takes the form of investments made in businesses pursuing one or more of the fund's objectives. These funds typically will be distributed as loans or equity investments, but a limited number

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Modified Accelerated Cost-Recovery System (MACRS)

Note: The One Big Beautiful Bill (OBBB) repealed the ability for "energy property" to qualify for the 5-year Modified Accelerated Cost-Recovery System (MACRS). Instead, the OBBB permanently restored 100% bonus depreciation in year one. The summary below discusses MACRS as it existed for energy property prior to the enactment of the OBBB. 

Prior to the OBBB, The Tax Cuts and Jobs Act of 2017 increased bonus depreciation to 100% for qualified property acquired and placed in service after September 27, 2017 and before January 1, 2023. Bonus depreciation steps down by 20% each year beginning with 80% in

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Business Energy Investment Tax Credit (ITC)

Note: The One Big Beautiful Bill (OBBB) made significant changes to this tax credit. To qualify for the tax credit, solar and wind energy systems must be either placed in service by December 31, 2027, or construction must commence by July 4, 2026. Additionally, the tax credit is not available for systems that commenced construction after December 31, 2025 if the facility or property includes any material assistance from a prohibited foreign entity.

The tax credit for non-solar and wind technologies (combined heat and power, energy storage, hydropower, and geothermal) will experience the following step-down in value:

  • Construction commences
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