Origin Energy has invested in four new coal ash storage silos at Eraring Power station as part of a push to increase recycling of the waste product.

The state government has also agreed to help the company find new customers for the product as part of the agreement to keep the plant running for another two years.

About 200 million tonnes of coal ash waste is currently dumped in unlined sites across NSW, with more than half of the material stored in the Hunter and Central Coast.

The new Eraring silos, which are in the process of being commissioned, will provide the option to supply multiple grades of coal ash to the market.

Transport for NSW previously sourced 63,000 tonnes of coal ash from Eraring for use on the Woolgoolga to Ballina project in concrete pavement.

Construction of the Scone Bypass used approximately 1500 tonnes of ash sourced from the Vales Point power station. Similarly, the M1 upgrade between Kariong to Somersby used fly ash in rigid pavements.

Origin Energy has also constructed a private haul road at Eraring paved with a product with 92 per cent ash content.

"We continue to work with our existing customers to increase recycling offtake and recently completed installation of additional onsite storage silos which will see an annual 50kt uplift in ash supplied to one of our customers. As part of our closure planning, we are exploring options for the future recovery and reuse of material directly from the ash dam and we're also in discussions with the EPA and Transport for NSW about the reform of standards that govern the use of ash in pavement and road projects," an Origin Energy spokesman said.

Lake Macquarie MP Greg Piper, welcomed the commitment to greater recycling.