The West Australian government will spend almost $3 billion on a renewable battery storage system and wind generation as part of a major overhaul of its energy network as it prepares for the retirement of coal-fired power plants.

Premier Mark McGowan will outline the $2.8 billion spend in Thursday’s state budget, which will fund the construction of a 500 megawatt battery energy storage system in the southern coal town of Collie before the end of 2025.