How do I know if my grid emission factor already includes T&D losses?

Read the factor's own documentation. The Greenhouse Gas (GHG) Protocol says to check whether transmission and distribution (T&D) losses are already inside an emission factor before you calculate Category 3, and to prefer factors that are split into parts. T&D losses belong in Category 3, not Scope 2, and should be counted once.

Why the check matters

The GHG Protocol's Category 3 guidance explains that in some regions electricity emission factors include life cycle activities, such as transmission and distribution of electricity, or extraction, processing and transport of the fuels used to make it. Those non-generation activities are counted in Scope 3, Category 3, rather than in Scope 2.

So a factor that mixes generation with T&D losses cannot simply go into Scope 2 and then be topped up again in Category 3. The guidance asks buyers of factors to look for transparent, disaggregated factors, and asks factor developers to publish them. Splitting them avoids counting the same emission twice.

What to read on the factor sheet

1. What it covers: only emissions at the power plant, or the full life cycle including fuel supply and T&D losses.
2. Whether T&D losses appear as their own line or percentage, or are folded into one number.
3. Which year and which grid, region or country the number describes. The guidance asks that combustion and life cycle factors match in time, technology and geography.
4. If the sheet is silent on all three, ask the publisher before you use it. Silence is not a yes.

How the two parts are calculated

Upstream emissions of purchased electricity use this rule: upstream factor = life cycle factor minus combustion factor minus T&D losses. The guidance adds the note that T&D losses are subtracted only if they are included in the life cycle factor, and that you should check the factor to establish whether they are.

T&D losses themselves are calculated as electricity consumed x life cycle emission factor x T&D loss rate. For the rate you can collect it from your electricity provider for the grid you use, or use a national, regional or global average. The guidance points to a World Bank database of loss rates by country.

What to write in your method note

• The factor's publisher, edition and year.
• Whether it includes T&D losses, and how you found out.
• The loss rate used and its source, if you calculated Category 3 T&D losses.
• That T&D losses are in Category 3 and not in your Scope 2 figure.

Example: 100,000 kWh a year, factor includes T&D losses (example figures)

• Example life cycle factor: 0.95 kg CO2e per kWh. Combustion at the plant: 0.82. T&D loss rate: 8%
• T&D losses: 100,000 x 0.95 x 0.08 = 7,600 kg CO2e (Category 3)
• Upstream factor: 0.95 minus 0.82 minus (0.95 x 0.08 = 0.076) = 0.054, so 100,000 x 0.054 = 5,400 kg CO2e (Category 3)
• Category 3 from electricity: 5,400 + 7,600 = 13,000 kg CO2e, the same as 100,000 x (0.95 minus 0.82)
• Without the check: treating the whole 0.13 as upstream (13,000 kg) and adding T&D losses again (7,600 kg) gives 20,600 kg CO2e, 7,600 kg too much

Example factors, not published values. Scope 2 would use the 0.82 generation part: 82,000 kg CO2e.

What Senseible does here

Senseible reads the kWh on your electricity bills and applies the Central Electricity Authority grid factor for the bill's financial year in Scope 2, with the factor shown on the line. Work out T&D losses separately, using the steps above.

• Category 3: T&D losses and well-to-tank
• T&D losses or AT&C losses
• Upstream fuel factor from the same source
• Calculators

Sources: GHG Protocol, Technical Guidance for Calculating Scope 3 Emissions, Category 3 (Chapter 3)

Last reviewed 2026-11-04. Check the notes of each new grid factor edition for whether T&D losses are included.