The US energy regulator has accepted Daybreak Power’s application for a preliminary permit for its proposed 2,200 MW Navajo Energy Storage Station (NESS) near Page, Arizona.

The Federal Energy Regulatory Commission’s (FERC) decision marks an “important early milestone” for $3.6bn project, according to Daybreak, which will use existing transmission infrastructure at the retired Navajo Generating Station coal plant, according to renews.biz.

NESS is a pumped storage hydropower facility that will use water from Lake Powell and a new reservoir on a plateau above the lake to create a large battery, using cheap, abundant solar and wind energy to pump water to the upper reservoir.

This is then released through turbines to generate 10 hours of renewable energy each day to power cities in California, Arizona and Nevada when demand peaks late in the day and through the night.

The NESS facility is Daybreak’s second energy storage project, following its proposed 1,540 MW pumped Storage facility that will use water from Lake Mead and transmission infrastructure near Hoover Dam.