How does an Agra potato cold store count emissions from an HFC top-up?
Gas added to top up the system replaces gas that leaked, so the kilograms added are a fair measure of Scope 1 leakage. Multiply by the refrigerant's global warming potential: 1,530 for HFC-134a under IPCC AR6. Ammonia systems have a GWP of zero, so their leaks add no CO2e.
Steps
Take kg of refrigerant charged from the service invoice.
Check the gas name on the invoice, not the equipment plate.
Multiply by its GWP (AR6), and report as Scope 1.
Blends
For a blend such as R-404A, work out the GWP from its components and their shares. Keep the calculation with the invoice.
Worked example: one top-up (illustrative quantity)
- HFC-134a charged: 40 kg
- Scope 1: 40 x 1,530 = 61,200 kg CO2e
The quantity is illustrative; the GWP is from IPCC AR6.
What Senseible does here
Senseible reads electricity bills (CEA grid factor 0.710 kg CO2 per kWh, CO2 Baseline Database version 21.0) and diesel, LPG and gas invoices (IPCC 2006 defaults) into a dated, fingerprinted Scope 1 and 2 record for each site. Intensity per unit uses the activity count you enter, and estimates are labelled as estimates.
Sources: IPCC AR6 Working Group I, Chapter 7 (GWP values), GHG Protocol Corporate Standard
Last reviewed 2026-10-21.