Downstream industrial investment in a proposed Special Economic Zone: an ex-ante conditional CGE appraisal of Mekar Putih, South Kalimantan, Indonesia

This study assesses the conditional economy-wide impacts of downstream industrial investment associated with the proposed Mekar Putih Special Economic Zone in South Kalimantan, Indonesia. A 10-sector regional computable general equilibrium (CGE) model uses a RAS-updated input–output database with hybrid cell injection for emerging nickel and silica processing. Investment, export-capacity, and productivity shocks represent assumed additions to the baseline rather than evidence that the zone will attract investment. Under the main scenario (S3), an annual investment injection of IDR 108 trillion increases provincial gross regional domestic product (GRDP) by 15.94% and generates approximately 84,900 jobs. At 50% additionality, the GRDP gain declines to about 7.8%. Comparison with the proponent’s feasibility study suggests a medium-term GRDP gain of approximately 8–12%, conditional on investment realisation. The full value-chain scenario (S5) yields 49.85%, illustrating an upper bound rather than a forecast. Normalised GRDP responses of 0.147–0.185 percentage points per trillion rupiah indicate that differences across scenarios largely reflect investment scale. District-level effects are allocated top-down. These estimates should not be interpreted as net welfare gains.