Electrale's air compressors will be used at Kirkland Lake Gold's Holloway mine, part of its Holt operation. Courtesy of Electrale Innovations.

Natural Resources Canada (NRCan) announced on Wednesday that it will invest $2.1 million in Electrale Innovations Ltd, a clean technology company developing low-energy alternatives to the mechanical air compressors that are currently used in underground mining.

Electrale, led by Laurentian University mining engineering professor Dr. Dean Millar, has developed a hydraulic air compressor (HAC) that uses water and gravity to compress air in underground mines.