Energy consumption is often a useful starting point for assessing the climate impact of production. Expressing that consumption as a carbon footprint requires further data and a defined methodology. Three questions help establish the scope: which equipment consumed the energy, how much electricity falls within the period studied, and which method will convert that consumption into emissions.
1. Define the equipment covered by the measurement
A production line may include the main machine, a dryer, pumps, cooling equipment and shared services. The record should identify the electrical points actually measured, the period and the operating condition. When allocating a shared load to several products, document the allocation method so that each product is assigned its appropriate share of the consumption.
2. Link energy to actual production
To compare products or operating conditions, record quantities, mass, rejects and the duration of the period, as required by the indicator. Specific energy consumption can be calculated in kWh per kg or per part only when both measurements cover the same time period and production scope. State whether the denominator includes all units produced or only conforming units.
3. Convert electricity into emissions using a documented factor
An initial estimate of electricity-related emissions requires an applicable emission factor, its unit, geographical coverage, reference period, source and accounting method. For a consistent boundary, the basic relationship is: estimated emissions (kg CO₂e) = electricity (kWh) × factor (kg CO₂e/kWh). The result depends on the electricity included and the emissions methodology selected. Always state the source and applicability of the factor used.
4. Establish how electricity-related emissions contribute to the product carbon footprint
ISO 14067:2018 addresses the quantification and reporting of a product carbon footprint using life cycle assessment principles. An estimate covering only electricity used during manufacturing may provide one input to that assessment, or form part of a partial study with a clearly stated scope. Demonstrating conformity with ISO 14067 and assessing the product’s complete life cycle require the corresponding methodology and additional inputs.
5. Define the result the business needs
Plant management may need to identify avoidable consumption; an environmental manager may need activity data for a greenhouse gas inventory; and a customer or brand may need to assess the footprint of packaging using life cycle data and rules. These projects are related, with distinct boundaries and deliverables.
How can KERN IoP contribute?
Energy instrumentation records electricity consumption at selected connections. Combined with reliable production data, these records can support comparable indicators across equipment, products and operating conditions. Emissions and product-footprint calculations also require the appropriate methodology, factors and other inputs. See KERN Energy, machine and auxiliary equipment measurement or the guide to defining the cell’s energy measurement boundary.
For more on periods outside production and auxiliary loads, see how to analyse standby consumption in an injection moulding cell.
Methodological sources
International Organization for Standardization. (2018). ISO 14067:2018 — Greenhouse gases — Carbon footprint of products — Requirements and guidelines for quantification. Official ISO entry (edition confirmed by ISO in 2024).
GHG Protocol. (2015). Scope 2 Guidance. Official publication. Guidance on corporate accounting for emissions from purchased electricity, heat, steam and cooling.
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