Canadian power generation and wholesale marketing company TransAlta has acquired a 50% stake in an early-stage development pumped hydro energy storage (PHES) project in Alberta.
TransAlta has formed a partnership with Montem Resources Limited, owner of the 320MW Tent Mountain Renewable Energy Complex PHES plant in the southwest of the province. Montem is a mineral exploration company headquartered in Australia, with its core activities including developing coal mines for steelmaking.
The pair will jointly manage the project, and TransAlta will be its developer, while the acquisition includes a share of Tent Mountain’s land rights, fixed assets and intellectual property.
The closed-loop PHES plant would have an expected operational lifetime of more than 80 years and would have up to 15 hours storage duration (320MW x 15 = 4,800MWh). Key advantages of the site selection include topography that includes an existing upper reservoir – Tent Mountain is in fact the site of a decommissioned Montem mine, and the reservoir was part of that.
Technical and environmental work has already been done including hydrology assessment. Up next will be additional geotechnical analysis, which is being carried out this year.
On the expected closing of the transaction next month, TransAlta will pay Montem an initial CA$8 million and make additional payments of up to CA$17 million (US$12.63 million) as the project moves forwards.
The company, which has over 5.7GW of assets in operation in its home country, in addition to just over 1.2GW in the US and 500MW in Australia, announced the transaction yesterday.
That includes 100% ownership of 17 existing hydroelectric power plants in Alberta and the province’s the largest wind portfolio, while the company was behind Alberta’s first-ever large-scale battery storage project – at one of its wind farms – completed in late 2020.
The Tent Mountain project is anticipated to come online and begin commercial operation in the 2028-2030 timeframe, if construction can get underway “as early as 2026,” TransAlta said.
“The Project can support the reliability of the Alberta grid with a proven technology that is non-emitting and has a significantly larger capacity and duration than other currently available storage options. We believe long-duration storage projects, like Tent Mountain, are essential to support the reliability of the grid in Alberta as wind and solar penetration increase on the path to net-zero electricity,” TransAlta CEO and president John Kousinioris said.
As the full Tent Mountain Renewable Energy Complex monicker implies, there could be other resources built as part of the project: the TransAlta-Montem agreement includes the IP for a 100MW green hydrogen electrolyser and 100MW offsite, onshore wind generation facility.