Pioneer Plant Risk Index (PPRI): a source-resolution protocol for first-of-a-kind plant performance databases

This technical note defines the vocabulary, source hierarchy and coding rules used to build databases of realised versus promised performance of first-of-a-kind (FOAK) industrial plants. It addresses a specific methodological problem: outcome data for pioneer plants is dispersed, and failure is systematically under-reported relative to success. The protocol sets out a six-level source hierarchy that varies by field type, demoting promoter communications for outcome variables; explicit conflict-resolution rules; a confidence scale; a silence rule treating absence of evidence as a weak negative signal; and a mandatory separation between pre-FID cancellation (financing risk) and post-FID underperformance (technology risk). A worked example from the NER300 bioenergy cohort is included. The protocol is published prior to the derivation of any results, so that definitions cannot be fitted to data. Spanish and English versions are included in this record.