eqcost

README

eqcost — equipment cost estimation & optimization

A single, dependency-free Go binary for process-equipment costing and 1-D economic optimization using the Turton bare-module method. It ships a Cobra CLI plus an interactive Bubble Tea TUI — both drive the same in-process compute core (internal/core): Turton Cp0/Fp/Fm correlations, CEPCI escalation, golden-section + Newton optimizers, plant cost sheets, and CSV/TXT export.

No Python, no runtime dependencies, no config — the equipment catalog is compiled into the binary. Run it from anywhere.

┌─ eqcost (one static binary) ─────────────────────────────┐
│  internal/cli   Cobra commands                            │
│  internal/tui   Bubble Tea app (Boardroom theme)          │
│  internal/core  Turton costing · optimizers · projects    │
│                 · export · embedded catalog.toml          │
└───────────────────────────────────────────────────────────┘

Install

go install github.com/Jubel075/eqcost/cmd/eqcost@latest

Or grab a prebuilt binary from the Releases page (linux / macOS / Windows, amd64 + arm64). Build from source:

git clone https://github.com/Jubel075/eqcost
cd eqcost
go build -o eqcost ./cmd/eqcost

Requires Go ≥ 1.24 to build; the binary itself has no dependencies.

Use

eqcost                        # interactive TUI (or: eqcost tui)
eqcost estimate --type pump_centrifugal --size 50 --material CS --pressure 50
eqcost tower --type tower_sieve --diameter 1.5 --trays 25 --material CS  # composite tower
eqcost optimize --case economic_pipe_diameter            # live convergence
eqcost batch --file examples/batch.toml                  # cost a list with totals
eqcost project new "Ammonia plant" --from examples/batch.toml  # saved cost sheet
eqcost list                                              # catalog
eqcost validate                                          # sanity-check a catalog
eqcost version                                           # build + schema info

Add --json to any command to emit the raw result bundle instead of a table.

Composite tray tower

tower costs a distillation column as one item — a vertical-vessel shell plus N trays, with Turton's tray-quantity factor F_q on the tray group — instead of hand-composing it via batch. The shell's pressure factor uses the real column diameter (a column's L/D ≫ 3, so deriving it from volume would be wrong).

eqcost tower --type tower_sieve --diameter 1.5 --trays 25 --material CS --pressure 5
eqcost tower --type tower_sieve --diameter 2.0 --trays 12 --height 14   # explicit height

Catalog highlights: the fired heater carries alloy factors (CS/Cr-Mo/SS) and a pressure factor; a centrifugal fan (fan_centrifugal_backward, whose pressure input is ΔP in kPa rise, shown in the output) and a fixed-roof storage tank round out the set. Fan/tank F_BM are figure-read approximates — flagged in catalog.toml for verification off Turton Fig. A.19; the Cp0 + pressure factors are cited/verified.

Operating cost (annualized TAC)

Supply a utility draw to fold annual operating cost + capital recovery into a total annualized cost (TAC) alongside the installed-capital numbers:

eqcost estimate --type pump_centrifugal --size 50 --util-rate 50 --util-price 0.12 \
                --hours 8000 --rate 0.10 --life 10 --capital-basis c_tm

--util-rate is consumption per operating hour in whatever unit --util-price is quoted against (kept unit-agnostic). Omit --util-rate for capital only.

Sensitivity sweep

Vary one economic parameter across a range and watch the optimum move (re-runs the case at each sample). Available in the TUI optimize form (a Sweep picker) and headless:

eqcost optimize --case economic_pipe_diameter \
    --sweep electricity_price --sweep-lo 0.04 --sweep-hi 0.24 --sweep-points 6

Export a run

Write any single run — an estimate, tower, optimize, or sweep — to a CSV (field/value, or a points table for a sweep) or a TXT report. Add --export PATH; the format follows the extension (.csv/.txt, default TXT) or an explicit --export-format:

eqcost estimate --type pump_centrifugal --size 50 --export pump.csv
eqcost tower --type tower_sieve --diameter 1.5 --trays 25 --export tower.txt
eqcost optimize --case vessel_ld --volume 10 --export vessel.csv

In the TUI, press e on a results screen, pick the format, and it writes an auto-named file (e.g. centrifugal-pump.txt) to the working directory.

CEPCI escalation

Costs escalate by CEPCI from the 2001 correlation basis to --year (table in the catalog). For a year past the table, pin the index directly instead of extrapolating:

eqcost estimate --type pump_centrifugal --size 50 --year 2027 --cepci 820

Custom catalog

The bundled catalog (equipment correlations + CEPCI table) is compiled into the binary as the default data source. Point at your own TOML with --config:

eqcost estimate --config ./my_catalog.toml --type pump_centrifugal --size 50 ...
eqcost validate --config ./my_catalog.toml

Plant projects (saved cost sheets)

A project turns the ephemeral batch into a named, saved equipment list you can reopen, edit, re-cost (to a new year), and export. Each project is one human-editable TOML file <slug>.toml under the XDG data dir (~/.local/share/eqcost/projects/).

eqcost project new "Ammonia plant" --year 2022 --from examples/batch.toml
eqcost project add ammonia-plant --tag P-101 --type pump_centrifugal --size 50 \
                  --pressure 50 --service "reflux pump"
eqcost project list                          # saved projects
eqcost project show ammonia-plant            # cost sheet + category subtotals
eqcost project show ammonia-plant --year 2024  # re-escalate to a new year
eqcost project rm ammonia-plant --tag P-101  # remove an item by tag
eqcost project export ammonia-plant --csv    # or --txt; --out PATH overrides
eqcost project delete ammonia-plant

Exports land in the current directory by default (--out to override): CSV (row per item + a TOTAL row, for spreadsheets) or TXT (a printable report — title block, aligned item table, totals + category subtotals, service notes).

In the TUI, the Projects menu entry opens a picker (＋ New project or a saved sheet); the editor adds s save · S save-as · e export · o open · n new · d delete (in the picker) on top of add/delete/live-totals.

Tool preferences

Optional defaults live in ~/.config/eqcost/config.toml (XDG). Both are overridable per command:

[defaults]
year    = 2024                 # default --year (CEPCI escalation)
catalog = "/path/catalog.toml" # default --config

Layout

Path	Role
cmd/eqcost	main — wires up the Cobra root
internal/core	Turton costing, optimizers, projects, export, embedded catalog; Run job dispatcher
internal/cli	Cobra commands
internal/tui	Bubble Tea app (Boardroom theme)
internal/paths	XDG data/config path resolution (projects dir, config file)
internal/contract	typed job/result structs

Method & validation

Costing follows Turton, Bailie, Whiting & Shaeiwitz, Analysis, Synthesis and Design of Chemical Processes (App. A): log10(Cp0) polynomials, the F_BM = B1 + B2·Fm·Fp factor form (and direct F_BM per material), and CEPCI escalation from the 2001 basis. Optimizers cross-check two independent methods (golden-section vs Newton) and validate the numeric optimum against a closed form.

internal/core ships tests that reproduce the Turton hand-calcs (pump, exchanger, vessel, fired heater, fan/tank, tray tower) and the optimizer closed-form gates:

go test ./...

License

MIT © 2026 Guillian