Form 8-K

8-K — Soluna Holdings, Inc

Accession: 0001493152-26-018192

Filed: 2026-04-21

Period: 2026-04-21

CIK: 0000064463

SIC: 6199 (FINANCE SERVICES)

Item: Regulation FD Disclosure

Item: Financial Statements and Exhibits

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UNITED

STATES

SECURITIES

AND EXCHANGE COMMISSION

WASHINGTON,

D.C. 20549

FORM

8-K

CURRENT

REPORT

Pursuant

to Section 13 or 15(d) of the Securities Exchange Act of 1934

Date

of Report (Date of earliest event reported): April 21, 2026

SOLUNA

HOLDINGS, INC.

(Exact

name of Registrant as Specified in Its Charter)

Nevada

001-40261

14-1462255

(State

or Other Jurisdiction

Incorporation)

(Commission

File

Number)

(IRS

Employer

Identification

No.)

325 Washington Avenue

Extension

Albany, New York

12205

(Address of Principal

Executive Offices)

(Zip Code)

Registrant’s

Telephone Number, Including Area Code: (516) 216-9257

N/A

(Former

Name or Former Address, if Changed Since Last Report)

Check

the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under

any of the following provisions:

☐

Written communications

pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

☐

Soliciting material pursuant

to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

☐

Pre-commencement communications

pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

☐

Pre-commencement communications

pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Securities

registered pursuant to Section 12(b) of the Act:

Title

of each class

Trading

Symbol(s)

Name

of each exchange on which registered

Common stock, par value

$0.001 per share

SLNH

The Nasdaq Stock Market

LLC

9.0% Series A Cumulative

Perpetual Preferred Stock, par value $0.001 per share

SLNHP

The Nasdaq Stock Market

LLC

Indicate

by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§ 230.405

of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§ 240.12b-2 of this chapter).

Emerging

growth company ☐

an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying

with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. ☐

Item

7.01 Regulation FD Disclosure.

April 21, 2026, Soluna Holdings, Inc. issued a press release announcing a new expansion of its partnership with Blockware. A copy of

the press release is attached hereto as Exhibit 99.1 and is incorporated by reference herein.

The

information in Item 7.01 and in Exhibit 99.1 will not be treated as “filed” for the purposes of Section 18 of the Securities

Exchange Act of 1934 (the “Exchange Act”) or otherwise subject to the liabilities of that section. This information will

not be incorporated by reference into any filing under the Securities Act of 1933, as amended, or into another filing under the Exchange

Act, unless that filing expressly incorporates this information by reference.

Item

9.01 Financial Statements and Exhibits.

(d)

Exhibits.

99.1

Press Release, dated April 21, 2026

104

Cover Page Interactive Date File (embedded with the

Inline XBRL document)

SIGNATURES

Pursuant

to the requirements of the Securities Exchange Act of 1934, as amended, the registrant has duly caused this report to be signed on its

behalf by the undersigned hereunto duly authorized.

SOLUNA HOLDINGS, INC.

Date: April 21, 2026

By:

/s/ Michael

Picchi

Michael Picchi

Chief Financial Officer

(principal financial officer)

EX-99.1

Filename: ex99-1.htm · Sequence: 2

Exhibit 99.1

Soluna

Announces Fourth Expansion with Blockware, Surpassing 17 MW of Total Capacity

New 3.3 MW deployment marks Blockware’s first

presence at Project Dorothy 1B

ALBANY,

NY, April 21, 2026

– Soluna Holdings, Inc. (“Soluna” or the “Company”) (NASDAQ: SLNH),

a developer of green data centers for intensive computing applications, including Bitcoin mining and AI, today announced a new expansion

of its partnership with Blockware. The agreement adds 3.3 MW of capacity at Soluna’s Project Dorothy 1B site in West Texas. This

marks Blockware’s fourth expansion with Soluna and its first deployment at Project Dorothy 1B.

With

this latest addition, Blockware becomes the first customer signed at Dorothy 1B, a 25 MW data center co-located with and powered by the

Briscoe Wind Farm. Soluna recently acquired the Briscoe Wind Farm in a $53 million transaction, enabling full vertical integration

between its energy generation and data center operations. Across all sites, Blockware’s total deployed capacity with Soluna now

exceeds 17 MW.

“We’re

excited to expand our partnership with Blockware for the fourth time and bring them to a new site,” said John Belizaire, CEO of

Soluna. “As we scale, we remain focused on delivering reliable, renewable-powered infrastructure for AI and Bitcoin mining.”

This

announcement follows a February expansion in which Soluna added 6 MW of capacity for Blockware at its Dorothy 1A site in West Texas.

Deployment for this most recent project began in March and supports Soluna’s model of delivering behind-the-meter digital infrastructure

that converts surplus renewable energy into high-performance computing.

“As

Blockware’s capacity needs continue to grow, Soluna has consistently delivered,” said Mason Jappa, CEO of Blockware. “Their

ability to launch new sites allows us to deepen our partnership and scale alongside them.”

Following

its acquisition of the Briscoe Wind Farm, which powers all Project Dorothy sites, Soluna has also announced plans to develop Project

Dorothy 3 at the same campus. The Company expects to share additional updates as development progresses.

For

more information about Soluna and its projects, visit solunacomputing.com.

Safe

Harbor Statement by Soluna

This

announcement contains forward-looking statements. These statements are made under the “safe harbor” provisions of the U.S.

Private Securities Litigation Reform Act of 1995. These forward-looking statements include all statements, other than statements of historical

fact, regarding Soluna’s expectations with respect to the deployment timeline of the additional capacity at Project Dorothy 1B,

development of Project Dorothy 3, and other statements that are predictive in nature. These forward-looking statements can be identified

by terminology such as “will,” “expects,” “anticipates,” “future,” “intends,”

“plans,” “believes,” “estimates,” “confident,” and similar statements. Soluna may also

make written or oral forward-looking statements in its periodic reports to the U.S. Securities and Exchange Commission (“SEC”),

in its annual report to shareholders, in press releases and other written materials, and in oral statements made by its officers, directors,

or employees to third parties. Statements that are not historical facts, including but not limited to statements about Soluna’s

beliefs and expectations, are forward-looking statements. Forward-looking statements involve inherent risks and uncertainties, further

information regarding which is included in the Company’s filings with the SEC. All information provided in this press release is

as of the date of the press release, and Soluna undertakes no duty to update such information, except as required under applicable law.

About

Soluna Holdings, Inc. (Nasdaq: SLNH)

Soluna

is on a mission to make renewable energy a global superpower, using computing as a catalyst. The Company designs, develops, and operates

digital infrastructure that transforms surplus renewable energy into global computing resources. Soluna’s pioneering data centers

are strategically co-located with wind, solar, or hydroelectric power plants to support high-performance computing applications, including

Bitcoin Mining, Generative AI, and other compute-intensive applications. Soluna’s proprietary software MaestroOS(™) helps

energize a greener grid while delivering cost-effective and sustainable computing solutions and superior returns. To learn more, visit

solunacomputing.com and follow us on:

● LinkedIn:

linkedin.com/company/solunaholdings/

● X

(formerly Twitter): x.com/solunaholdings

● YouTube:

youtube.com/c/solunacomputing

● Newsletter:

bit.ly/solunasubscribe

● Resource

Center: solunacomputing.com/resources

Soluna

regularly posts important information on its website and encourages investors and potential investors to consult the Soluna investor

relations and investor resources sections of its website regularly.

About

Blockware

Solutions, LLC (“BWS”) is an American company specializing in blockchain infrastructure and cryptocurrency mining services.

Founded in 2017 and headquartered in Houston, Texas, Blockware Solutions provides comprehensive solutions, including mining hardware

sales, secure data center hosting, and blockchain investment advisory services. The company also operates a large-scale network of mining

farms and contributes to the decentralization of the Bitcoin network. Leveraging its technical expertise and commitment to transparency,

Blockware helps individuals and institutions grow their digital asset businesses. For more information, visit www.blockwaresolutions.com.

Contact

Public

Relations

West

of Fairfax for Soluna

Soluna@westof.co

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