Skip to main content
Every figure in Salvidia comes from the same simple equation, applied thousands of times across your data:
Emissions = activity data × emission factor
This page walks through what each side of that equation means, and how individual calculations roll up into your footprint.

​
Activity data: the “how much”

Activity data quantifies something your organisation did. It comes in two forms:

Physical quantities

Kilowatt-hours of electricity, litres of diesel, kilometres flown, tonnes of waste. This is the more accurate form — it measures the activity directly.

Spend

Dollars spent on a category of goods or services. Used when physical quantities aren’t available — which, for most of a supply chain, is the practical reality.

​
Emission factors: the “how dirty”

An emission factor converts a unit of activity into greenhouse gas emissions — kilograms of CO₂e per kWh, per litre, per dollar spent in an industry. Factors come from published, referenced sources and vary by geography (the same kWh has a very different footprint on different electricity grids) and by category. How Salvidia selects them is covered in Emission factors.

​
A worked example

Say your ledger and bills for the year contain: Each line is calculated independently: quantity × factor = kg CO₂e. Each result is tagged with its scope and category, and the totals you see on the dashboard are simply the sum of every one of these line-level calculations. There’s no adjustment layer between the data and the total.

​
Why this matters for audit

Because the chain is data → factor → line result → total, every number in a Salvidia report can be decomposed back to its inputs:
  1. The total breaks into scopes and categories
  2. A category breaks into the individual entries inside it
  3. An entry shows its activity data and the factor applied
That traceability is what “audit-ready” actually means: not a certificate, but the ability to answer “where did this number come from?” at every level, with sources.

​
CO₂e and global warming potentials

Different greenhouse gases trap different amounts of heat. Methane, refrigerants, and nitrous oxide are far more potent than CO₂ per kilogram. Emission factors already account for this by converting everything to CO₂ equivalent (CO₂e) using published global warming potentials — which is why one unit can describe your entire footprint.

​
The accuracy hierarchy

Not all inputs are equal, and the methodology is honest about that:
  1. Measured physical data (metered kWh, fuel receipts) — most accurate
  2. Calculated physical data (distances from travel records) — very good
  3. Spend-based estimates (industry-average factors on your ledger) — broad coverage, lower precision
The standard practice: use spend for coverage, then upgrade your largest categories to physical data over time. Each upgrade tightens the whole footprint where it matters most. See Activity-based vs spend-based for the full trade-off.