In July 2011, Connecticut enacted legislation amending the state's Renewables Portfolio Standard and creating two new classes of renewable energy credits (RECs): Zero Emission Renewable Energy Credits (ZRECs) and Low Emission Renewable Energy Credits (LRECs). A Zero Emission Renewable Energy Facility is one that produces no emissions, such as solar, wind, or hydro. Owners of these facilities have an opportunity to sell their ZRECs to the utility at a fixed price for a period of 15 years. 

In coordination with the state's other investor-owned utility, the United Illuminating (UI) Company offers owners of small ZREC projects (less than or equal to 100 kW) the opportunity to enroll in the Small ZREC Tariff Program. The Small ZREC price is set at additional 10% of the Medium ZREC Weighted Average Bid Price. For 2015 (Year 3) of procurement, Small ZREC Tariff rate was set at $84.01. 

The program is available on a first-come, first-served basis. The utilities are required to conduct solicitations up to 6 years. Sellers must register with NEPOOL Generation Information System and must apply to the Public Utilities Regulatory Authority (PURA) and be qualified as an RPS Class 1 generator. Equipment must be located behind the meter and have a dedicated ZREC meter. Customers may not have received funding or grants for the system from the state's Clean Energy Finance and Investment Authority (although customers that have received low cost financing are eligible).