Sydney’s biggest water storage, Lake Burragorang, could soon help NSW take a big step toward achieving its transition to renewable energy and stabilise electricity supply at peak demand times.

ZEN Energy, Australia’s first 1.5°C energy company, is proposing to turn degraded coal industry land at Nattai on the escarpment above the lake into a clean energy powerhouse, delivering on-demand electricity to the equivalent of 500,000 homes and businesses.

At 1,000 megawatts (1GW), the Western Sydney Pumped Hydro project will be able to store and supply up to eight continuous hours of ‘firming’ energy, essential to stabilise the state’s electricity grid and power prices as it transitions to renewable energy generation.

Located 24km away from Warragamba Dam and drinking water treatment, the project will also be mostly underground: pumping water from Lake Burragorang through tunnels to a reservoir located on the former coal industry land. When demand is high, water is released to drive underground turbines and send renewable power into the electricity grid.

A $1 million per year Community Benefit Scheme will be created and the project will generate 1,500 jobs during construction and 80 operations jobs.

Coal was mined from the Burragorang Valley from 1930 to 1992 and the project site was used as a coal washery, operated by Burragorang Valley Coal, until 2001 and since then undergone rehabilitation. The Dunbier family, which owned the company, is now partnering with ZEN to turn the site’s fossil fuel past into being part of the state’s clean energy future.

Numerous studies, consultation and co-design with Traditional Owners, local residents and other stakeholders will now occur. If all approvals and a social licence are secured, construction could begin in 2027 and be operational by 2031.

Initial studies have established that the project would have no detrimental impact on water quality or cause any change to water levels in Lake Burragorang, including no flooding of the shoreline and surrounding natural environment. This was critical to securing WaterNSW’s approval for ZEN to progress the project.

“The vast water reserves of Lake Burragorang can supply Sydneysiders with clean drinking water and clean, renewable energy as well,” said ZEN CEO Anthony Garnaut.

“Large-scale energy storage projects like Western Sydney Pumped Hydro are key to keeping the lights on and energy prices in check in NSW as our coal-fired power stations age and retire over the next decade.”

“Western Sydney Pumped Hydro marks ZEN’s entry into renewable energy development in New South Wales. This is a key milestone for us as we grow and envision a 1.5-degree world for all.”

Importantly, consultation with key stakeholders, particularly Traditional Owner representatives, has already begun. These will continue as the project evolves and ZEN is seeking to co-design many aspects of the project with local residents.

“ZEN is committed to, and looking forward to, sharing and shaping the project design and its benefits with locals, Traditional Owners, Wollondilly Council, and other interested and important stakeholders,” Mr Garnaut said.