LCIA Methods

VoLCA computes environmental impacts by applying characterization factors from LCIA methods to inventory flows. Methods are loaded separately from databases, so you can mix and match.

Supported method formats

VoLCA loads methods from ILCD method packages — ZIP archives or directories containing XML files structured per the ILCD data format spec (used by GreenDelta’s openLCA and SimaPro).

Common method packages:

• EF 3.1 / EF 3.0 — European Commission PEF methods (available from European Commission)
• ReCiPe 2016 — Midpoint and endpoint methods
• CML 2002 — Classic midpoint method
• IPCC 2021 — Climate change characterization

Loading a method

Via config file (recommended for production)

[[methods]]
name = "EF3.1"
path = "/data/EF3.1"     # directory of ILCD XML files
load = true

Via CLI upload

Upload a ZIP or directory once, then it persists across restarts:

volca --config volca.toml method upload /data/EF3.1.zip --name "EF3.1"

Via the API

# List loaded methods
curl http://localhost:8080/api/v1/methods

# List method collections
curl http://localhost:8080/api/v1/method-collections

Listing available methods

# Flat list of all characterization methods
volca --config volca.toml methods

# Or via CLI
volca --config volca.toml --format table methods

Each method has a UUID that you pass to impacts and flow-mapping commands.

Computing LCIA scores

# Single method
volca --config volca.toml --db ecoinvent impacts <PROCESS_ID> --method <METHOD_UUID>

# Export to CSV
volca --config volca.toml --db ecoinvent impacts <PROCESS_ID> --method <METHOD_UUID> --csv scores.csv

Checking flow mapping coverage

Before running LCIA, verify how well the method maps to your database flows:

volca --config volca.toml --db ecoinvent flow-mapping <METHOD_UUID>

This shows:

• Total characterization factors
• How many are matched (and by what strategy: exact name, synonym, compartment fallback)
• How many are unmatched
• How many database flows are uncharacterized

# See which CFs are matched and how
volca --config volca.toml --db ecoinvent flow-mapping <METHOD_UUID> --matched

# See which CFs have no database match
volca --config volca.toml --db ecoinvent flow-mapping <METHOD_UUID> --unmatched

The 4-step matching cascade

When VoLCA matches a characterization factor to a database flow, it tries in order:

1. Exact name + compartment — full name and compartment match
2. Synonym — name matched via loaded flow synonym sets
3. Compartment fallback — name matched, compartment generalized (e.g. “air, low population density” → “air”)
4. Unmatched — no match found; this flow won’t contribute to the score

Low matching rates are normal for some method/database combinations. The --unmatched flag in flow-mapping shows exactly which characterization factors are missing.

Flow hotspot analysis

Find which flows drive an impact the most:

volca --config volca.toml --db ecoinvent impacts <PROCESS_ID> --method <METHOD_UUID>
# Result includes top contributing flows per category

Via API:

GET /api/v1/db/{db}/activity/{id}/contributing-flows/{collection}/{methodId}?limit=10
GET /api/v1/db/{db}/activity/{id}/contributing-activities/{collection}/{methodId}?limit=10