Evolve Power (formerly Montem Resources) is investigating converting the historical Tent Mountain Coal Mine into a renewable energy complex (TM-REX), located in the Crowsnest Pass of southwest Alberta, Canada. The planned development includes three primary elements; a 320MW pumped hydro energy storage (PHES), 100 MW green hydrogen electrolyser and a 100 MW offsite wind farm.

On 14 February 2023, Evolve Power signed a binding agreement with TransAlta TMPH LP, a wholly owned subsidiary of NYSE and TSX listed TransAlta Corporation to sell 50% of its TM-REX assets in Alberta, Canada. The sale includes rights to the Tent Mountain land, fixed assets and intellectual property associated with the TM-PHES, offsite green hydrogen electrolyser and offsite wind farm. The TM-PHES is expected to be developed over the next 4 years and subject to regulatory, commercial, and engineering considerations, could be ready for construction as early as 2026, with a target commercial operation date between 2028 to 2030.

In April 2023, the shareholders have approved completion of the sale of 50% of the TM-REX Project to TransAlta Corporation. Subject to the terms of the definitive agreements between the parties, TransAlta will pay C$24.7m for 50% equity interest in the TM-REX based on achieving development and commercial milestones. These cash flows will offset a significant portion of Evolve Power’s 50% share of the development costs.