Marmora energy storage

Converting an old mine into a giant hydro battery

The proposed Marmora Pumped Storage Project will diversify Ontario's electricity grid and support growing electrification demands. Located halfway between Toronto and Ottawa, this partnership between Ontario Power Generation (OPG) and Northland Power offers an innovative way to store clean, on-demand power while strengthening the local economy.

Nature’s battery

Marmora Pumped Storage key facts.

MW of energy storage

homes powered

or more years of potential service life

metre drop, or four times the height of Niagara Falls

jobs created (direct and indirect)

(up to) in annual economic benefit for eastern Ontario

70K - 140K
annual greenhouse gases displaced

Pumped about energy storage

The mine pit, which reaches a depth of more than 200 metres below ground level, was created for mining operations in the mid-20th century until it closed in the late 1970s. Today, the mine pit is filled with a combination of rain and ground water and has the potential to be converted into a clean energy asset.

The proposed Marmora Pumped Storage project would see the abandoned mine turned into a 400 MW pumped storage facility. The proposed closed-loop cycle design would recirculate the same water between two reservoirs to generate electricity. When demand and prices for electricity are low, water would be pumped up into an upper reservoir. When demand increases, that water would be released to the lower reservoir and run through turbines to create electricity when it’s needed most.

The Project also includes the potential for ~30 MW of solar generation located on the inactive mined lands. This would maximize the use of the former unrehabilitated mined lands while contributing additional clean electricity to the grid.

Pumped about power

The Marmora Pumped Storage Project could create new jobs and drive growth for the local economy.

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