Elevra Lithium (ASX:ELV) said the results of a pre-feasibility study confirmed the North American Lithium Brownfield Expansion in Canada as a "high-value" growth project that is expected to increase annual spodumene concentrate production while reducing unit operating costs, according to a Monday filing with the Australian bourse.

The expansion will be delivered through a three-stage brownfield development, with stage 1 increasing process plant throughput to the permitted rate of 4,500 tonnes per day (tpd) from 2027, stage 2 increasing milling capacity to 6,500 tpd from 2028, and stage 3 delivering a permanent crushing solution aligned with increased milling capacity by 2029, the filing said.

The study establishes an average annual production rate of 348,000 tonnes per annum and an average annual post-expansion production rate of 373,000 tonnes per annum, per the filing.

Shares fell nearly 4% in midday trade Monday.