Social Cost of Carbon and Social Cost of Methane

(a)The cost of carbon dioxide emissions shall be established by the Commission based on the most recent social cost of carbon dioxide developed by the federal government, in accordance with the following:#

(I)the cost of carbon dioxide emissions starting in 2020, shall not be less than the base cost of $68.00 per metric ton in 2020 dollars;#

(II)the Commission shall update the social cost of carbon values to the present dollar year for each year after 2020 by applying an escalation rate equal to or greater than the escalation rates established in the federal technical support document.#

(b)For net present value calculations of the social cost of carbon dioxide emissions, the utility shall use a discount rate equal to the lesser of 2.5 percent or the discount rate established by the federal technical support document.#

(c)The cost of methane emissions shall be established by the Commission based on the values set forth in the federal technical support document or on the federal government's most recent assessment of the global cost of methane as updated to reflect the latest available values derived from peer-reviewed, published studies, in accordance with the following:#

(I)the social cost of methane emissions, starting in 2020, shall not be less than the base cost of $1,756 per metric ton in 2020 dollars;#

(II)the Commission shall update the annual social cost of methane emissions values to the present dollar year for each year after 2020 by applying an escalation rate equal to or greater than the escalation rates established in the federal technical support document or the addendum to the 2016 federal technical support document if the social cost of methane is not included in the federal technical support document; and#

(III)the social cost of methane emissions shall use the best available leakage rates to determine the methane emissions from fossil gas extraction and processing, in addition to the greenhouse gas emissions identified in rule 4527, and consistent with § 40-3.2-107(2)(b), C.R.S.#

(d)For net present value calculations of the social cost of methane emissions, the utility shall use a discount rate equal to the lesser of 2.5 percent or the discount rate established in the federal technical support document.#

(e)For net present value calculations of portfolios of resources presented pursuant to rules governing clean heat plans or any type of DSM plan, the utility shall also present net present value calculations using the utility's weighted average cost of capital universally on all costs included within the relevant portfolio.#