Northwest Natural Holding Co

Certain businesses and activities of NW Holdings and NW Natural are aggregated and reported as other for segment reporting purposes.

The following businesses and activities are aggregated and reported as other under NW Natural, a wholly-owned subsidiary of NW Holdings:

•4.7 Bcf of the Mist gas storage facility contracted to other utilities, third-party marketers, and electric generators;

•natural gas asset management activities; and

•appliance retail center operations.

Mist Gas Storage

The Mist gas storage facility began operations in 1989. It is a 17.5 Bcf facility with 12.8 Bcf used to provide gas storage for the NGD business. The remaining 4.7 Bcf of the facility is contracted with other utilities, third-party marketers, and electric generators with these results reported in other.

The overall facility consists of seven depleted natural gas reservoirs, 21 injection and withdrawal wells, a compressor station, dehydration and control equipment, gathering lines, and other related facilities. The capacity at Mist provides multi-cycle gas storage services to customers in the interstate and intrastate markets. The interstate storage services are offered under a limited jurisdiction blanket certificate issued by FERC. Under NW Natural's interstate storage certificate with FERC, NW Natural is required to file either a petition for rate approval or a cost and revenue study every five years to change or justify maintaining the existing rates for the interstate storage service. Intrastate firm storage services in Oregon are offered under an OPUC-approved rate schedule as an optional service to certain eligible customers. Gas storage revenues from the 4.7 Bcf are derived primarily from firm service customers who provide energy-related services, including natural gas distribution, electric generation, and energy marketing. The Mist facility benefits from limited competition as there are few storage facilities in the Pacific Northwest region. Therefore, NW Natural has the ability to acquire high-value, multi-year contracts.

Asset Management Activities

NW Natural contracts with an independent energy marketing company to provide asset management services, primarily through the use of natural gas commodity exchange agreements and natural gas pipeline capacity release transactions. The results of these activities are included in other, except for the asset management revenues allocated to NGD business customers pursuant to regulatory agreements, which are reported in the NGD segment.

These include the following businesses and activities aggregated under NW Holdings:

•NW Natural Water Company, LLC (NWN Water) and its water and wastewater utility operations and water services business;

•NWN Water's equity investment in Avion Water Company, Inc.;

•NW Natural Renewables Holdings, LLC and its non-regulated renewable natural gas activities;

•a minority interest in the Kelso-Beaver Pipeline held by our wholly-owned subsidiary NNG Financial Corporation (NNG Financial); and

•holding company and corporate activities, including business development activities, as well as adjustments made in consolidation.

NW Natural Water

NWN Water currently serves an estimated 190,000 people through approximately 76,000 water and wastewater connections across six states. NWN Water continues to grow though customer additions within or near its service territories, and continues to pursue acquisitions. See further discussion about the status of water general rate cases in Part II, Item 7, "Results of Operations—Regulatory Matters—Water and Wastewater Utilities."

The water and wastewater utilities primarily serve residential and commercial customers. Water distribution operations are seasonal in nature with peak demand generally during warmer summer months, while wastewater is less seasonally affected. Entities generally operate in exclusive service territories with no direct competitors. Water distribution customer rates are regulated by state utility commissions while the wastewater businesses we own consist of some state regulated systems and some systems that are not rate regulated by utility commissions.

NWN Water launched its services business in April 2023. This business provides operations and maintenance services to water and wastewater system owners and works to create value by leveraging shared personnel, technology and expertise to support delivery of clean, reliable water at a reasonable cost. Today, NWN Water provides operations and maintenance services to approximately 25,000 connections.

NW Natural Renewables

NW Natural Renewables is an unregulated subsidiary of NW Natural Holdings established to pursue unregulated RNG activities. In September 2021, a subsidiary of NW Natural Renewables, Ohio Renewables, and a subsidiary of EDL, a global producer of sustainable distributed energy, executed agreements to secure RNG supply from two production facilities that are designed to convert landfill waste gases to RNG (EDL Facilities). The first facility was completed and commenced delivery of RNG to Ohio Renewables in September 2024. Upon reaching this milestone, Ohio Renewables paid $26.0 million to the EDL subsidiary. The second facility was completed and commenced delivery of RNG to Ohio Renewables in December 2024 at which time Ohio Renewables made an additional payment of $25.4 million to the EDL subsidiary.

Alongside these development agreements, Ohio Renewables and the subsidiary of EDL executed agreements for Ohio Renewables to purchase up to an annual specified amount of RNG produced by the EDL Facilities over a 20-year period at a contractually specified price. Ohio Renewables has contracted to sell the supply obtained from EDL at fixed-prices to investment grade counterparties.

Ohio Renewables has contracted to sell RNG produced by the EDL Facilities up to certain specified volumes in each of calendar years 2024 through 2026 to an investment-grade counterparty. We currently estimate RNG volumes to be sold pursuant to this agreement to be approximately 2,430,000 MMbtu over the life of the agreement, provided that such amounts of RNG are produced by the EDL Facilities during that period.

Ohio Renewables additionally has contracted to sell a fixed-volume of RNG under a long-term agreement with an investment-grade utility beginning in 2025 and extending through 2042. Amounts to be delivered under this agreement are estimated to be 112,500 MMbtu in 2025, 375,000 MMbtu in 2026, 1,950,000 MMbtu annually in 2027 through 2034, and 2,775,000 MMbtu annually in years 2035 through 2042. Under the current contract, if less than 75% of the contracted volumes of RNG are not delivered on an annual basis, Ohio Renewables is obligated to pay the per MMbtu price for volumes between the amount delivered and 75% of the contracted volumes on an annual basis.