OAR 860-150-0050
Environmental Attributes and Renewable Thermal Certificates


(1) The environmental attributes of RNG produced or purchased pursuant to these rules must include, but is not limited to, an estimated carbon intensity for the pathway utilized to produce, transport, and deliver RNG to a retail natural gas customer.
(2) Each large natural gas utility and each small natural gas utility that is authorized by the Commission to participate in the RNG program under these rules must use RTCs to track the chain of custody of the environmental attributes of RNG that is produced or purchased for the utility’s retail natural gas customers in Oregon. RTCs used for compliance with these rules must be issued, monitored, accounted for, and transferred by or through M-RETS.
(3) All entities that generate, acquire, purchase, sell, transfer, or broker the trade of RTCs for eventual use by a natural gas utility under these rules must register and maintain accounts in good standing with the M-RETS renewable energy certificate system. A natural gas utility may not use RTCs under these rules that are issued by, acquired from, or transferred by an entity that has not complied with all information, data reporting and verification requirements of the M-RETS system, including payment of registration and transaction costs.
(4) Each entity that generates RTCs pursuant to these rules must estimate the carbon intensity of the pathway for the RNG. To estimate the carbon intensity of the RNG, the entity generating RTCs must use one of the following, as appropriate to the pathway in question:
(a) A Tier 1 OR-GREET calculator or simplified calculator published by DEQ for the Clean Fuels Program;
(b) A Tier 2 OR-GREET calculator published by DEQ for the Clean Fuels Program;
(c) A Tier 1 CA-GREET calculator published by the California Air Resources Board (CARB) for use in the California Low Carbon Fuel Standards (LCFS) program, with the transportation and distribution cells modified for that RNG’s pathway to Oregon;
(d) A Tier 2 CA-GREET calculator published by CARB for use in the LCFS program, with the transportation and distribution cells modified for that RNG’s pathway to Oregon; or
(e) A methodology that a natural gas utility may otherwise be directed to use by Commission order.
(5) For any of the calculators described in section (4), entities submitting documentation to M-RETS are not required to use cells that would not apply to RNG delivered to retail natural gas utility customers, such as compression above normal pipeline pressures that would only be appropriate for compressed natural gas (CNG) vehicle fuels. In the Natural Gas Transport cells of the calculators, an entity may use the pipeline distance to a large or small natural gas utility’s city gate instead of pipeline distance to a CNG station.
(6) Each entity that generates RTCs pursuant to these rules must provide documentation to M-RETS regarding the carbon intensity of the pathway in question pursuant to section (4). That documentation must include:
(a) One of the calculators described in section (4), with the appropriate cells modified and values entered for the pathway in question; and
(b) A resultant carbon intensity value for the pathway in question.
(7) Upon the Commission’s request, each large natural gas utility and each small natural gas utility that participates in the RNG program must provide documentation to demonstrate that, for each RTC the natural gas utility purchased or otherwise acquired, one dekatherm of RNG was delivered to an injection point on a natural gas common carrier pipeline.
(8) A large natural gas utility must retire one RTC in the M-RETS system for each dekatherm of RNG counted towards the annual targets for a large natural gas utility established in ORS 757.396 (Participating large natural gas utilities).
(9) A small natural gas utility participating in the RNG program described in these rules must retire one RTC in the M-RETS system for each dekatherm of RNG counted towards the quantity of RNG the utility specified in its filing with the Commission pursuant to OAR 860-150-0400 (Mechanisms for Recovery of Prudently Incurred Costs by Small Natural Gas Utilities).
(10) Once retired, a RTC may not be sold, transferred, or claimed again by a natural gas utility or any other entity.
(11) A large natural gas utility or a small natural gas utility participating in the RNG program described in these rules must obtain attestation from the RTC generator demonstrating that:
(a) The entity claiming the environmental attributes represented by each RTC has the exclusive right to claim environmental attributes associated with the RNG;
(b) The environmental attributes, and the RTC that represents those attributes, are associated with RNG produced by a specific entity, in a specific location, using a specific process and a specific pathway; and
(c) The environmental attributes have not been used or claimed in any other program or jurisdiction.
(12) Each large natural gas utility and each small natural gas utility participating in the RNG program must retain the attestations described in section (11) and make them available for review by the Commission upon request.
(13) Each large natural gas utility and each small natural gas utility participating in the RNG program described in these rules must maintain records of each RTC retired under the RNG program, as well as the attestations described in section (11), for a minimum of five (5) years after the date on which the RTC was retired.
(14) The attestation described in section (11) of this rule may be made, stored, transferred and retained electronically through the M-RETS system to satisfy the requirements of sections (12) and (13) of this rule, or through another means specified by the Commission.
(15) Large natural gas utilities and small natural gas utilities may be directed by Commission order to use a generally-applicable RTC tracking system instead of the M-RETS system. In that event, all references to the M-RETS system in sections (2) through (14) of this rule shall apply to the designated RTC tracking system.
(16) For a large natural gas utility, an RTC generated during the target year, the preceding year or the subsequent year may be retired to comply with the annual RNG targets established in ORS 757.396 (Participating large natural gas utilities). For a small natural gas utility, an RTC may be retired during the year in which it is generated, during the subsequent year, or retired and applied to the year preceding the year the RTC was generated.
(17) An unused RTC expires, for the purposes of these rules, at 11:59 p.m. on December 31 of the year subsequent to the year during which the RTC was generated. A natural gas utility may not use an expired RTC to comply with these rules.

Source: Rule 860-150-0050 — Environmental Attributes and Renewable Thermal Certificates, https://secure.­sos.­state.­or.­us/oard/view.­action?ruleNumber=860-150-0050.

Last Updated

Jun. 8, 2021

Rule 860-150-0050’s source at or​.us