Report On Geothermal Potential In Sussex Region

Officials in Sussex say an abandoned potash mine near the town could become an exciting opportunity for the region’s economy.

A town-commissioned report has found “very real potential” to produce geothermal energy using water from the Penobsquis mine.

It comes more than three years after PotashCorp, now known as Nutrien, announced the closure of the mine.

“It’s an exciting opportunity that’s been identified following three years of extensive study,” said Scott Hatcher, the town’s chief administrative officer.

Town officials say the geothermal analysis was done in two parts. The initial technical feasibility study in 2017 and 2018 collected local data from PotashCorp, including ground temperatures, water levels and mineral composition of the brine.

The second phase of the study validating that data relied on more detailed samples taken from the mine site in May of 2019 once the mine cavity was fully flooded. The brine had a greater mineral composition and was colder than first expected, but the town says those details can be managed.

Open-Loop System Has Most Potential

After modelling 20 geothermal scenarios, Wood Environment & Infrastructure Solutions of Fredericton determined an open-loop system has the most potential. In that process, water would be pumped to the surface, run through heat pumps to generate heating and cooling power, and then return below ground after use.

Hatcher said the estimated project cost is $14.4 million with a payback period of between nine and 10 years.

“Any opportunity that’s developed within our greater region provides some level of support to the entire region, and Sussex will benefit a small amount from that there,” he said.

Hatcher said the next steps are to identify businesses which would benefit most from geothermal energy and develop a governance model.

He said council hopes to hand the opportunity off to an individual or group which wants to get into the energy business.

Potential Governance Models

There are two different approaches to capitalizing on the geothermal system, he said. One would be to set up a not-for-profit governance model like a new geothermal energy commission or utility board to run it. There is also potential for a large, single user to be interested in making the investment.

Hatcher said there is also a significant question to answer regarding provincial legislation.

“Will the province permit us to use the flooded resource 2,000 feet below the surface, take the heat or take the coolness out of that water, use it for an economic advantage, and return that brine back into the mine,” he said.

Once those three items are addressed over the coming months, Hatcher said a level of engineering would have to take place, along with the pre-screening or a full environmental impact assessment process, which could take up to two years to complete.

Hatcher said Nutrien, which still owns the mine, has been a tremendous partner as they worked through this process.

“They participated with us in all aspects of providing data, providing access to the flooded mine workings on their own property, they’ve committed funding to help us and assist us to assess the opportunity,” he said.