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The Lake Onslow project is designed to serve as a giant battery to help protect against hydro electricity shortages and create more stability in the market.
It would involve a man-made lake likely to the east of Roxburgh in Central Otago where water would be pumped into a reservoir when energy demand was low and released when demand was high.
The Ministry of Business, Innovation and Employment said Energy Minister Megan Woods would provide a brief project overview to her Cabinet colleagues this month.
A spokesperson confirmed a formal update to Cabinet was expected towards the end of June.
A decision on the project's feasibility was planned for December following geotechnical, engineering and environmental studies.
Part of the feasibility studies and investigation work would look at environmental impact, as raising the level of Lake Onslow would lose wetland that lead into it.
The project was estimated to take four to five years to build, with an additional two years for commissioning and filling.
At its construction peak, it was expected to create 3500 to 4500 skilled and semi-skilled jobs.