Transmission and distribution (T&D) losses are the electricity that is lost as it travels through the high-voltage transmission network and lower-voltage distribution network from power stations to the end consumer. Roughly 7–8% of UK grid electricity is lost in this way.
Why it matters
When a customer uses 1 kWh of electricity, generators have to produce slightly more than 1 kWh to compensate for the losses on the way. The emissions from that extra generation are real, but they are not captured under Scope 2 (which covers only the electricity actually consumed).
The GHG Protocol therefore places T&D-loss emissions under Scope 3 Category 3, Fuel- and Energy-Related Activities Not Included in Scope 1 or 2, alongside well-to-tank fuel emissions. The DESNZ dataset publishes a dedicated T&D loss factor each year.
A practical example
An office consuming 100,000 kWh of grid electricity has Scope 2 emissions of around 20 tCO₂e using a typical UK location-based factor. Applying the DESNZ T&D-loss factor adds roughly another 1–2 tCO₂e to Scope 3 Category 3, reflecting the additional generation needed to deliver that 100,000 kWh through the grid.
We include T&D losses in every engagement that reports Scope 2. See the full approach on the methodology page.