The revised front-end engineering and design study has boosted planned production by 20,000 tonnes per annum to 170,000tpa, refining plans for production of the company's K-Brite product, targeting the premium end of the sulphate of potash market.
Compared with the 2019 definitive feasibility study, Lake Wells pre-production capital expenditure has risen from A$208 million to $292 million.
Payback is 4.5 years, just six months longer than in the DFS.
The 20,000tpa increase in production will cost an extra $28 million upfront, while the decision to include granulation and bagging plants needed to tap into the premium slice of the market costing another $36 million.
A decision to switch from an engineering, construction and management contracting model to a lump-sum EPC model has added $14 million to costs, but managing director Matt Shackleton said more than 75% of the capex was now covered on a lump-sum basis, providing protection against time, and cost overruns.
The revised pre-tax net present value is now $614 million, down from $665 million, while internal rate of return has eased from 25% to 21%, however annual earnings have risen from $100 million to $124 million, while operating costs have fallen from US$262/t to $251/t.
The optimised FEED included a defined the borefield design, pond design, product mix and schedule.
Yesterday, APC secured its green loan verification, which "confirms that Lake Wells will make a positive environmental contribution to the global production of SOP, producing significantly less carbon emissions than Mannheim SOP".
APC is working on finalising its senior debt facility by mid-year, with Export Finance Australia offering A$45 million in debt, and the Northern Australian Infrastructure Facility adding $170 million. Commercial banks are expected to make up the balance.
Lake Wells, which is expected to become Australia's second potash brine development, is said to have Australia's largest measured resource at 18.1 million tonnes.
The development will rely heavily on renewable energy, and has been designed to produce Australia's lowest carbon footprint SOP, with around one-third of the emissions attributable to a comparable-sized Mannheim SOP development.
Five binding take-or-pay agreements have been struck covering 90% of the optimised forecast output.
The company had hoped to reach FID in the March quarter, and still aims to reach steady state production planned for 2023.
APC shares were steady at A17.5c, valuing the company at $97 million.
