CONFIDENTIAL DRAFT (Form 8-K)

CONFIDENTIAL DRAFT

Soluna and Bitdeer Expand Agreement to 35 MW at Project Kati 1

Amendment adds approximately 7 MW and brings the deployment to approximately 2.42 EH/s, fully subscribing the site's K1BC phase

ALBANY, NY, September 28, 2026 - Soluna Holdings, Inc. ("Soluna" or the "Company") (NASDAQ: SLNH), a developer of green data centers for intensive computing applications, including AI and Bitcoin mining, today announced an amended agreement with Dory Creek, LLC, a wholly owned subsidiary of Bitdeer Technologies Group ("Bitdeer") (NASDAQ: BTDR), a world-leading technology company for AI and Bitcoin mining infrastructure. Under the amendment expanding the partnership, Bitdeer will deploy approximately 7 MW of additional Bitcoin mining equipment at Soluna's Project Kati 1 in South Texas, bringing its total deployment at the site to 35 MW and approximately 2.42 EH/s of hash rate. Hash rate is measured in exahashes per second (EH/s) and reflects the computing power dedicated to Bitcoin mining. This marks the first expansion of the partnership and is expected to be complete in November 2026.

Project Kati 1 is an 83 MW wind-powered data center in Willacy County, Texas. The Bitdeer deployment is located in the site's K1BC phase, which is now fully subscribed.

The agreement takes the form of a co-mining arrangement, a structure Soluna introduced to its Bitcoin platform in August. Soluna provides the site, power, and turnkey operations; Bitdeer provides and owns its Sealminer A2 Pro Air mining equipment, and the parties share in the mining proceeds the deployment generates. The amendment carries the same structure as the original agreement.

"We entered our first co-mining agreement with Bitdeer in August, and we are expanding it before that deployment is even finished," said John Belizaire, CEO of Soluna. "That is the strongest endorsement either of us could give the structure. Kati 1 is fully spoken for, and the operating history we are building there is what makes the next site possible."

For more information, visit www.solunacomputing.com.