Methodology

FreeLCA implements the ISO 14040 / 14044 Life Cycle Assessment framework across seven sectors on one shared, industry-agnostic engine. Impact characterization uses EPA TRACI 2.1 and IPCC AR6 GWP, with free, redistributable factors from EPA eGRID, the Federal LCA Commons, and the published sources listed per industry below.

The four LCA phases

1. Goal & Scope. Choose the industry and a functional unit (per m³ treated, per MWh, per vehicle-km, per tonne managed, per package, per m²·yr, per kg product…), the system boundary, the region, and the service life.
2. Life Cycle Inventory (LCI). Each template is a parametric model that expands to a list of elementary flows (emissions to air/water/soil and resource use) tagged to a lifecycle stage. Grid electricity is expanded with the project's region factors; embodied materials and fuels roll up through published per-unit factors.
3. Life Cycle Impact Assessment (LCIA). Multiply elementary flows by characterization factors and aggregate by impact category, reporting totals and the contribution by item, substance, and lifecycle stage.
4. Interpretation. Hotspot detection, typical-range benchmarks, plain-English insights, sensitivity tornado charts, and scenario comparison.

Methodology by industry

Each industry ships pre-built templates whose default values are typical-value estimates from the cited sources, every one user-overridable. Each pack is held to a published literature-range validation test in our build, so a clean default scenario must land in its expected band.

Impact assessment methods & categories

TRACI 2.1 (North America, seeded default)

EPA's Tool for Reduction and Assessment of Chemicals and Other Environmental Impacts: Global Warming Potential, Acidification, Eutrophication, Smog Formation, Ozone Depletion, and Human-Health Particulate.

Resource categories

Land Use (m²·yr) and Water Consumption (m³) supplement TRACI for the sectors that need them — essential for Food & Agriculture and material to Energy and Buildings — so a solar farm's land footprint or a crop's irrigation water is not lost.

Global Warming Potential

IPCC AR6 100-year GWPs: CO₂ (1), fossil CH₄ (29.8), biogenic CH₄ (27.0), N₂O (273), and common refrigerants. Biogenic CO₂ (from biomass, food, paper) is treated as carbon-neutral; biogenic CH₄ (landfills, livestock, paddies) is fully counted. Electricity emissions use eGRID by subregion, so a battery-electric vehicle or an all-electric building reflects the grid it actually draws on.

Regional method selection

Geography is a first-class dimension: a project carries a region, and the default LCIA method follows it — TRACI 2.1 for North America, EF 3.1 (EU Environmental Footprint) for Europe, and ReCiPe 2016 as a global option. Region→method routing and US/Canada + EU + world-region mapping are built in. Grid carbon-intensity factors are seeded for the US (eGRID subregions) and ~28 international regions (EEA / Ember / IEA, 2023), so carbon footprints — which are method-independent (IPCC AR6 GWP) — are accurate worldwide on the local grid. The EF 3.1 and ReCiPe characterization factors for the non-carbon categories are the priority next ingest; until then those categories use TRACI factors. Where a high-quality local value is unavailable a clearly-labeled global Rest-of-World proxy is used rather than silently presenting a US factor as local.

Allocation & co-products (ISO 14044)

Templates carry an allocation method (none / mass / economic / energy / system expansion) with a documented default. Where co-products are unavoidable — dairy milk vs meat, CHP heat vs power, recycling avoided burden — the basis is stated so results are transparent. Food factors use already-allocated published values to avoid double-counting.

Reference-data versioning

Every project pins a reference-data version (eGRID year + LCIA method version + IPCC report, per region). Existing projects keep the version they were created with — guaranteeing reproducibility — and you can explicitly upgrade and compare the deltas.

Limitations

• v1 uses direct foreground "inventory × characterization factor" calculations. Full upstream supply-chain chasing via matrix inversion is on the roadmap.
• Template defaults are typical-value engineering / literature estimates, not substitutes for site- or product-specific data when available. Agricultural and waste emissions in particular are highly variable in practice.
• Embodied factors are cradle-to-gate values from public LCI/EPD sources; they are planning-grade and not third-party-verified EPDs.
• Results inform decisions but should be reviewed by a qualified LCA practitioner before any regulatory submittal, comparative assertion, or public disclosure.

Citations

• Bare, J.C. (2012). TRACI 2.1: User's Guide. U.S. EPA.
• IPCC AR6 WG1 (2021), Chapter 7 Supplementary Material; GHG Protocol GWP update (2024).
• IPCC (2019). Refinement to the 2006 IPCC Guidelines, Vol. 5 (Waste) & Vol. 4 (Agriculture).
• NREL Life Cycle Assessment Harmonization (generation carbon intensity).
• Argonne National Laboratory, GREET model (vehicle & fuel cycle).
• U.S. EPA WARM — Waste Reduction Model (disposal & recycling avoided burden).
• Poore, J. & Nemecek, T. (2018). Reducing food's environmental impacts. Science 360.
• RICS Whole Life Carbon Assessment; LETI & Carbon Leadership Forum embodied-carbon benchmarks (EN 15978).
• Inventory of Carbon & Energy (ICE) database; PlasticsEurope, International Aluminium Institute, FEVE, FEFCO EPDs.
• EPA eGRID; European Environment Agency & EU JRC EF 3.1 (regional roadmap).
• Federal LCA Commons / USLCI.