Nature of Operations

3 Months Ended

Mar. 31, 2026

Organization, Consolidation and Presentation of Financial Statements [Abstract]

Nature of Operations

1. Nature of Operations

Description of Business

Unless the context requires otherwise in these notes to the consolidated condensed financial statements, the terms “SHI,” “ the “Company,” “we,” “us,” and “our” refer to Soluna Holdings, Inc. together with its consolidated subsidiaries, “SDI” refers to Soluna Digital, Inc., “Soluna Cloud” or “Cloud” refers to Soluna Cloud, Inc., “SEI” refers to Soluna Energy, Inc., and "Soluna Wind" refers to Soluna Wind Holding, Inc.

Soluna Holdings, Inc. (“SHI”) is a digital infrastructure company that specializes in transforming surplus renewable energy into computing resources. The Company’s strategy is to operate data centers co-located with wind, solar, and hydroelectric power plants, supporting compute-intensive applications, including Bitcoin mining, generative AI, and high-performance computing (“HPC”). This approach aims to create a more sustainable grid while providing cost-effective and environmentally friendly computing solutions.

Soluna Holdings, Inc., was originally incorporated in the State of New York in 1961 as Mechanical Technology, Incorporated and reincorporated in the State of Nevada on March 24, 2021. On March 23, 2021, SHI's common stock commenced trading on The Nasdaq Stock Market LLC ("Nasdaq"). Headquartered in Albany, New York, the Company changed its name from “Mechanical Technology, Incorporated” to Soluna Holdings, Inc. on November 2, 2021. On October 29, 2021, Soluna Callisto Holdings, Inc. ("Soluna Callisto") merged into Soluna Computing, Inc. (“SCI”), a private green data center development company and subsidiary of SHI, in which SCI was subsequently sold and transferred all its assets in December 2023 to the Company. SHI currently conducts its business through its wholly owned subsidiary, Soluna Digital, Inc. (“SDI”). Additionally, SHI formed Soluna Cloud, Inc. (“Soluna Cloud”) on March 24, 2024, to operate cloud, colocation, and data hosting services related to high performance computing and AI. On April 2, 2024, SHI formed Soluna Energy, Inc. (“SEI”) to own and manage renewable energy power purchase agreements and land leases through a series of service subsidiaries. In January 2026, SHI formed Soluna Wind Holdings, Inc. to own and operate wind-powered energy generation facilities through its subsidiaries.

As of March 31, 2026, the Company has five operating sites under management. In 2021, the Company constructed a 25 MW data center and commenced operations in its Murray, Kentucky location ("Project Sophie"). The Company’s Texas site (“Project Dorothy”), located at the Briscoe wind farm, holds the potential for up to 100 MW of power generation. By June 2024, SHI had energized 50 MW of the site across two phases, Project Dorothy 1A and 1B. As of March 31, 2026, SHI holds a 14.6% Class B membership interest in Soluna DVSL ComputeCo, LLC (“DVSL”), owner of Project Dorothy 1A, and a subsidiary of SHI holds a 100% Class A membership interest in DVSL. Subsequent to March 31, 2026, the Company purchased the remaining 85.4% Class B Membership Interest in DVSL and the Company now owns 100% of the issued and outstanding membership interests in DVSL, see Note 16 for details. SHI also holds a 51% ownership interest in Soluna DV ComputeCo, LLC (“DVCC”), owner of Project Dorothy 1B. On July 22, 2024, the Company closed financing for the 48 MW data center (the “Project Dorothy 2”). Project Dorothy 2 is financed by Soluna2 SLC Fund II Project Holdco LLC, an investment vehicle of Spring Lane Capital (“SLC”) and SDI. As of March 31, 2026, SDI has 100% Class A membership and 0% Class B membership interest in Project Dorothy 2. On July 22, 2025, the Company closed financing with SLC for a 35 megawatt (MW) expansion of Project Kati, a data center campus in Willacy County, Texas, with Project Kati 1, which has a capacity of 83 MW. The funds and further contributions are being used for the construction of Project Kati 1 that began in the third quarter of 2025. As of March 31, 2026, SDI has 100% Class A membership and 13% Class B membership interest in Project Kati 1.

On April 1, 2026, the Company acquired 100% of the equity interests in Briscoe Wind Farm, LLC ("Briscoe"), a 150 MW capacity wind generation project. See Note 16 for details.