Useful Numbers

These numbers are the sort of things I use all the time to calculate the impact of different activities.

Contents: - Energy consumption - GHG emissions - Fuel density and GHG emissions intensity - Passenger travel emission factors - Freight emission factors - UK population - Water energy properties - Greenhouse gases GWP

Energy consumption

 PWh/yearMWh/person/yearkWh/person/daycontinuous kWpopulation
World primary energy16020552.38 billion
UK primary energy2.030823.467 million
UK final energy 1.5 23 63 2.6

World data from Our world in data (data for 2022)
UK data from Statista, data for 2021

Primary energy consumption counts fuel used to generate and transmit electricity rather than the electricity itself. The final energy consumption is what is actually delivered.

GHG emissions CO2 equivalent

 Mt/yeart/person/yearkg/person/day
World (total)54,0006.818.5
World (from energy use)36,8004.612.6
UK total5027.520.5

World data from EDGAR - Emissions Database for Global Atmospheric Research: GHG emissions of all world countries 2023 report and IEA CO2 emissions in 2022s. UK data from UK Environment Accounts (for 2021)

Fuel density and GHG emissions intensity

Electricity (delivered) 207gCO2e/kWh
Electricity (inc generation and losses)257gCO2e/kWh
Gas (HHV)180gCO2e/kWh
Heating oil (HHV)270gCO2e/kWh
Coal (HHV)340gCO2e/kWh
Petrol (biofuel blend)2100gCO2e/litre
Petrol (LHV)9.4kWh/litre
Petrol (LHV)230gCO2e/kWh
Diesel (biofuel blend)2510gCO2e/litre
Diesel (LHV)10.6kWh/litre
Diesel (LHV)250gCO2e/kWh
Oil11630kWh/tonne
Oil1600kWh/barrel

From UK Government GHG Conversion Factors for Company Reporting 2023

Passenger travel emission factors

Air travel includes radiative forcing

 gCO2e/km
Average diesel car167
Average petrol car177
Average hybrid car109
Bus (local)118
Bus (London)78
National rail35
International rail4.5
Airline domestic273
Airline short haul (economy)183
Airline long haul (economy)200

Souce as above. This data varies from year to year, for example as vehicles become more efficient.

Freight emission factors

Freight by tonnage (average laden)

 gCO2e/tonne-km
HGV Articulated(average laden)75
HGV Rigid (average laden)178
Light van (diesel)571
Light van (petrol)720
Rail28
Ship general13
Ship bulk3.5
Ship container16
Ship refrigerated13
Air short haul1668
Air long haul1099

Freight vehicles by distance

 gCO2e/km
HGV Articulated (average laden)835
HGV Rigid (average laden)906
Light van (diesel)231
Light van (petrol)201

From DeFRA as above

UK population

67,000,000people (2021)
28,200,000households (2021)

Population and households from the ONS

Water energy properties

specific heat4.2kJ/kg/K
specific heat0.00117kWh/kg/K
latent heat vaporisation2260kJ/kg
latent heat vaporisation0.628kWh/kg

Greenhouse gases - global warming potential

 20 year100 year
Methane81-8327-30
Nitrous oxide273273

From IPCC Sixth Assessment Report (via ERCC)

The GWP is a measure of the global warming impact of a gas relative to CO2e (by mass, comparing 1 kg of the gas with 1 kg of CO2e). This depends on the timescale as well because different gases have different lifetimes in the atmosphere. For example methane has a half life of about 12 years and over a longer timescale it has less effect.