Under the enlarged scenario, output in the first stage has gone from around 23,000 tonnes per annum of graphite concentrate to 83,400tpa, with capital costs rising from an estimated US$29 million to $78 million.

With the increased scale - throughput from 200,000tpa to 800,000tpa - cash costs have dropped from $576/t to $344/t.

Under the new estimates, the project has a payback period of 3.7 years.

An expansion to 145,000tpa of graphite concentrate output is still pitched from years four to 40.

Regarding financing of the initial A$108 million capital cost, Siviour continues to believe 60% of the funding could come from Holland after last month receiving a "letter of Interest … for export credit agency (ECA) cover from Atradius Dutch State Business (Atradius), the Government of the Netherlands official ECA, a government credit guarantee scheme".

According to Renascor, the Dutch ECA scheme was identified as applicable to Siviour based on the sourcing of Dutch content through Renascor's Dutch strategic engineering partner, Royal IHC.

"ECA Cover from Atradius is often used to assist Dutch exporters in winning export transactions and increasing the capacity to raise finance from banks for projects involving Dutch exports," Renascor said.

Shares in Renascor were up 10% to 2.2c in afternoon trade, capitalising the company at $24 million.