Prices & Overrides

Operating costs are only as good as their prices. Jasper ships honest defaults and an append-only override system for replacing them with your own.

Default prices

Category	Source	Notes
Electricity	EIA (US industrial average)	real public data
Natural gas	EIA	real public data
Steam	two-factor model	capital component + energy component coupled to the gas price — re-prices automatically if you override gas
Chemicals	published TEA literature	representative values (e.g. benzene ≈ $1.10/kg); flagged in every estimate that uses them

Chemical prices are currently sourced for the US-GC region. Other regions scale CAPEX via location factors but may show price gaps until overridden.

Overrides

An override is an event, not an edit:

• Append-only. Overrides are recorded in an event log with the new value, reason, context, and actor. A database trigger blocks updates and deletes — the audit trail is immutable.
• Scoped. Each override targets a scope: scenario, project, or global.
• Newest wins within a scope; the most specific scope wins overall:

scenario  →  project  →  global  →  default (sourced seed value)

A scenario-level benzene price beats the project-level one, which beats a global one, which beats the literature default. Every resolved price reports which layer it came from (default or override + scope), so estimates remain auditable.

API

POST /api/tea/override          record an override event (API-key gated)
GET  /api/tea/overrides         query the event log
GET  /api/tea/price/chemical    effective price for a CAS number (override-aware)
GET  /api/tea/price/utility     effective utility price (override-aware)

estimate_project resolves all feed, product, and utility prices through the same chain — pass a project/scenario reference and the whole estimate re-prices consistently.