Impact methodology

How the Repair Impact estimate works.

Version 1.0.0, reviewed 2026-09-01. This page records the model's sources, assumptions, illustrative communication range and limits.

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01 — Formula

A straightforward comparison, not a lifecycle assessment.

Indicative CO₂e impact deferred

= annualised manufacturing impact × selected life-extension years × decision weighting × quantity

− estimated technician travel impact

Manufacturing impact is annualised using the source's representative product life. The calculation is capped at that reference life. Travel is applied once to the selected total service journey, even when multiple items are repaired during that visit.

02 — Product factors

Published category averages.

CategoryManufacturingReference lifeRepresentative mass proxySource
Washing machine 341.0 kg CO₂e 12.0 years 65.0 kg (Washing machine) Impact CO₂ / ADEME
Dishwasher 271.0 kg CO₂e 12.0 years 47.0 kg (Dishwasher) Impact CO₂ / ADEME
Refrigerator 257.0 kg CO₂e 10.0 years 51.0 kg (Fridge-freezer) Impact CO₂ / ADEME
Electric oven 218.0 kg CO₂e 12.0 years 56.0 kg (Electric cooker) Impact CO₂ / ADEME
Laptop 182.0 kg CO₂e 5.0 years 3.0 kg (Laptop) Impact CO₂ / ADEME
Smartphone 79.3 kg CO₂e 2.5 years 0.5 kg (Mobile phone) Impact CO₂ / ADEME
Television 328.0 kg CO₂e 8.0 years 22.0 kg (40–46 inch display) Impact CO₂ / ADEME

Product manufacturing factors are representative Impact CO₂ / ADEME category data. Product mass uses the closest suitable category from Merseyside Recycling and Waste Authority average weights as a transparent proxy. For example, the refrigerator manufacturing factor uses a fridge-freezer mass proxy, and the electric-oven factor uses an electric-cooker mass proxy. These values are not measurements of the user's item.

03 — Travel factor

A UK-oriented service-visit deduction.

The calculator converts the selected total mileage to kilometres and applies 0.16152 kg CO₂e per km. The factor represents an average petrol car and comes from the UK Government GHG Conversion Factors 2026.

It does not model vehicle type, traffic, routing, parts delivery, repeat visits or journeys shared across multiple jobs.

In summary: product manufacturing factors use representative Impact CO₂ / ADEME data, while technician travel uses a UK 2026 government conversion factor. This is an indicative eServ V1 model, not an item-specific UK lifecycle analysis.

04 — eServ assumptions

Decision weightings distinguish the selected scenario.

Repair chosen instead of replacing now100% weighting

This scenario assumes the repair directly defers a replacement purchase.

Repair is likely, but I am still comparing65% weighting

This scenario reduces the estimate because the final decision is not yet certain.

Diagnosis first; the outcome is unclear35% weighting

This scenario uses a cautious weighting while repair feasibility remains unknown.

These weightings are transparent eServ V1 modelling assumptions, not published probabilities of repair success.

05 — Limitations

Use the result as an order of magnitude.

  • The model does not assess the actual fault, parts, materials or repair energy.
  • It does not compare the in-use energy efficiency of the current and replacement products.
  • It does not account for refrigerant leakage, hazardous materials or specific disposal routes.
  • Potential product mass kept in use is a representative proxy, not a verified recycling or landfill outcome.
  • The ±35% band is an illustrative communication range. It is not derived from a probability distribution.
  • Safety, compliance and reasonable repairability take priority over an estimated environmental benefit.
Not certified carbon accounting.

The calculator is public decision support. It must not be used as an official carbon inventory, offset claim, product environmental declaration or proof that a specific repair has reduced emissions.