Know your data sources.

ONS (Operador Nacional do Sistema Elétrico) — Brazil's national electricity grid operator. Public Tempo Real REST/JSON feed, no credentials. Real-time national system load (SIN, ~77 GW), generation mix by source (hydro, thermal, wind, solar, nuclear), marginal operating cost (CMO) by submarket (Southeast/Center-West, South, North, Northeast) in R$/MWh, the energy balance snapshot (generation, load, import/export and interchange by submarket plus international ties with Argentina/Paraguay/Uruguay), and reservoir energy storage (EAR). Joins the power-markets family (ercot/spp/nyiso/caiso/aemo/cammesa/eirgrid).

Petroleum-engineering calculations, pure compute, no data source, no auth. Deterministic correlations in field units (Rs scf/STB, pressure psia, temp °F, API °API). Pairs with production/well data connectors (rrc, enverus, welldatabase) to turn raw data into engineering answers. 550+ methods across: PVT, gas/oil/water properties, EOS (Peng-Robinson/SRK flash), decline-curve (Arps + SEDM/PLE/LGM/Duong), IPR (Vogel/Fetkovich/Joshi), VFP multiphase lift (Beggs-Brill/Hagedorn-Brown/Gray), material balance, well-test/PTA, SCAL, hydraulic fracturing, surface facilities, flow assurance, artificial lift (ESP/rod/gas-lift), petrophysics/log analysis (Archie), drilling hydraulics, geomechanics/pore pressure, reserves and economics (NPV/IRR), tubular design, and ~100 unit conversions.