Datasets provide the environmental impact data that converts a quantity into a calculated impact - per-unit values for indicators like GWP, acidification, eutrophication, ozone depletion, water use, and more. (You’ll often hear this called emission factors; we use the broader term because Datasets cover more than just carbon.) Most of your Inventory Elements - Materials, Energy, and Processes - need a Dataset connected before Inputs that point to them can produce a calculated footprint. The chain is Input → Element → Dataset: an Input is a row in your Product (LCA) with a quantity; it points to an Element (a Material, Energy, Process, or Transport from your Inventory); the Element is connected to a Dataset that supplies per-unit impact data. Because Datasets attach at the Element level, every Input that references the same Element shares the same impact data. This guide explains how to find and connect the right Dataset for each Element.Documentation Index
Fetch the complete documentation index at: https://docs.variable.global/llms.txt
Use this file to discover all available pages before exploring further.
Transport works a little differently. A Transport Element is a modeled lane made up of one or more legs, and the Dataset connections live on the legs (each leg has its own mode). When you add transport to an Input, you pick a lane and set the weight - you don’t pick a Dataset. The workflow on this page applies to Material, Energy, and Process Elements.
What are datasets?
Think of a Dataset as a recipe — for one unit of this material, process, or activity, here’s what it costs the environment. Datasets contain that per-unit impact data: how much CO2e (and other environmental impacts like acidification, eutrophication, ozone depletion, water use, and energy use) are associated with one unit. For example, a steel Dataset might indicate that producing 1 kg of steel generates 2.1 kgCO2e. When that Dataset is connected to a Material Element (“Hot-rolled steel sheet”) and an Input in your Product (LCA) specifies a quantity of 10 kg of that Element, Variable calculates the impact as 21 kgCO2e. The same pattern works for electricity Datasets connected to Energy Elements (kgCO2e per kWh × kWh consumed) and natural-gas Datasets connected to Process Elements (kgCO2e per m3 × m3 consumed).The quality of your carbon footprint depends on choosing appropriate datasets. More specific datasets (by geography, production process, or supplier) generally yield more accurate results.
Where you can assign a dataset
Datasets attach at the Element level, but you can open the search results from several places depending on where you are in the app:- From an Input row in a Product (LCA) - click the Element name in the row to open its details panel, then click Assign dataset. The panel also shows the Element’s per-unit impact (or
--.--if no Dataset is connected yet) and lets you add alternatives or remove the Input. Useful when you’re working on a Product (LCA) and notice an Element is missing its Dataset. - From the Element itself - open a Material, Energy, or Process Element from your Inventory and assign its Dataset directly. Every Input that already points to this Element picks up the change.
- From an Inventory list - the Materials, Energy, and Processes lists let you assign Datasets in bulk. Select multiple Elements and assign a Dataset to all of them at once. This is the fastest way to fill in Datasets after a BOM import.
How to assign a dataset
The flow below uses an Input from a Product (LCA) as the entry point, but the search results behave the same way whether you opened them from an Element, an Inventory list, or an Input row.Open the search results
Click the Element name in an Input row to open its details panel. The panel shows the Element with its per-unit impact (
--.-- if no Dataset is connected yet). Click Assign dataset to open the search results.Start with your Inventory
The search results open on the Inventory tab, which lists Datasets your company has already added (whether imported from a database, created manually, or pulled in from a previous assignment). Re-use one of these whenever possible - it keeps your impact data consistent across Product (LCA)s and avoids duplicating the same Dataset under different names. Only switch to the Database tab if your Inventory doesn’t have a suitable match; once you connect a Database Dataset to an Element, it joins your Inventory and is available to re-use across other Product (LCA)s.
Search and filter
Use the search box for a free-text query (e.g., “steel”, “aluminium”, “polyethylene”). To narrow results further, click the + button next to the active filter chips and add one or more filters. Filters and free-text search compose - every chip narrows the result set.The search results reuse the standard filter component, so the same filters are available here as elsewhere in the app:
| Filter | What it narrows |
|---|---|
| Footprint type | Model, Imported, Transport, Switch, Mix, Dataset, etc. - useful for restricting to raw Datasets vs. modeled Elements |
| Inventory | Limit to a specific Inventory grouping |
| Category | Taxonomy category (Metals, Plastics, Chemicals, etc.) |
| Source | Data source - a specific database (ecoinvent, DEFRA, Ember, etc.) or a supplier |
| Geography | Region (Europe, EU27 & EFTA, Global) or country |
| Location / Location type | A specific named location, or a kind of location (factory, warehouse, port, etc.) |
| Unit type | Weight, volume, energy, etc. - handy when you know the Dataset must be priced in a particular unit dimension |
| Scope | GHG Protocol scope (1, 2, 3, Transport, Purchased goods, etc.) |
| Org / Supplier / Customer | The org unit, supplier, or customer the item is associated with |
| Created by / User | Filter by the original creator or by a user who has touched the item |
| Activity group | A specific activity grouping |
Some filters are pre-set depending on context - for example, opening the search from a Material Element typically pre-applies Category: Material and Footprint type: Dataset so you only see compatible reference Datasets. Click the × on any chip to remove it, or click the reset icon to clear all filters at once.
Review the result rows
Each result row shows the key facts about the Dataset directly in the list, so you can compare options without leaving the search:
| Field | Description |
|---|---|
| Name | Full name of the Dataset |
| Database | Source database (ecoinvent, DEFRA, etc.) |
| Geography | Region the data represents |
| Unit | Reference unit (per kg, per kWh, etc.) |
| GWP | Global warming potential per unit |
| Year | Data reference year |
Today, clicking anywhere on a result row selects that Dataset - there is no separate “view details” interaction in the search results. Use the Select button on the row (or just click the row) to connect it. We plan to add a richer detail preview here in the future.
Taxonomy alignment
Variable uses a taxonomy system to ensure datasets are appropriate for your Elements. A Dataset should match or be more specific than the Element’s category. For example:- An Element categorized as “Metals > Steel” can use Datasets for “Metals > Steel > Hot-rolled steel”
- An Element categorized as “Metals > Steel” should not use a Dataset for “Metals > Aluminium”
Resolving a category mismatch
If you select a Dataset whose category doesn’t match the Element’s category, the search results flag it with a Category mismatch warning and show the conflict - for example, “Your element is categorized as Material but this dataset is in Energy > Fuel > Liquid > Diesel.” You then have two options:- Update category & select - click this button in the warning to re-categorize the Element to match the Dataset and connect it in one step. Use this when the Dataset is correct and the Element’s category was wrong (common after a BOM import where categories were inferred from limited data).
- Pick a different Dataset - close the warning and choose a Dataset whose category aligns with the Element. Use this when the Element’s category is correct and the mismatched Dataset isn’t the right fit.
If you cannot find a Dataset for an Element, check that the Element’s taxonomy category is correct. A more general category may give you access to more Datasets.
Available databases
Variable provides access to several environmental impact databases:| Database | Coverage | Description |
|---|---|---|
| ecoinvent (3.8, 3.11) | Global | Thousands of datasets covering materials, energy, transport, and processes (premium) |
| DEFRA 2022 | UK | UK government greenhouse gas reporting conversion factors |
| Ember (2022, 2024, 2025) | Global | Annual electricity impact data by country and grid, from Ember’s Global Electricity Review |
| US EPA eGRID 2022 | US | US electricity grid impact data, from the EPA’s Emissions & Generation Resource Integrated Database |
| AIB | Europe | European Residual Mix factors from the Association of Issuing Bodies |
| Idemat 2023 | Global | Material environmental impact data from Delft University of Technology |
| IPCC AR6 | Global | Global warming potentials from the IPCC Sixth Assessment Report (Working Group I) |
| WIOD | Global | Spend-based, industry-average impact data from the World Input-Output Database |
Database availability depends on your subscription. Get in touch at support@variable.co if you need additional databases.
Tips for choosing datasets
Match geography when possible
A dataset for steel produced in Germany is more accurate for German steel than a global average. Choose datasets that match your supply chain geography.
Consider production technology
Different production methods have different impacts. Primary aluminium has much higher emissions than recycled aluminium.
Check the reference year
Emission factors change over time as energy grids decarbonize and production methods improve. Recent datasets are generally more accurate.
Use supplier data when available
If your supplier provides their own emission data (via EPD or direct sharing), use that instead of generic database values.
Pick a conservative proxy when there's no exact match
The reference databases don’t cover every material or process - if you can’t find an exact match, pick the closest proxy and lean toward a more carbon-intensive option so you don’t understate the impact. Document your rationale (in the Element’s notes or in your LCA report) so a third-party verifier can see why you made the choice. If you need something more specific, you can also model the missing item from its own inputs rather than relying on a single proxy Dataset.
What’s next
You now have a complete life cycle model of your product. To track real-world flows — what you actually buy, sell, and consume — across a reporting period, move on to Activities.Track activities
Record purchases, sales, and consumption to build a corporate carbon account