Resource consumption values impact on CO2 emissions
To observe the impact of portfolio emissions, one can take emission factors of the resources and their sub-types into account.
What is an emission factor?
An emission factor (EF) is a coefficient that describes the rate at which a given activity releases greenhouse gases (GHGs) into the atmosphere. (EPA 2022) It is used to estimate emissions from various sources, such as industrial processes, transportation, and energy production. Higher EF value is associated with higher emissions, resulting higher impact, e.g. how many kg of global green house gases are emitted by 1 kWh of natural gas?
Find below the main information to be taken into consideration when performing analysis of the portfolio CO2 emissions.
Resource types and impact on CO2 portfolio emissions:
Type | Resource | Sub-type | Emission Factor Value | Impact on CO₂ emissions |
Energy | District energy | District cooling | ** | |
District heating | ** | |||
Electricity | Electricity from grid (normal contract) | ** | ||
Electricity from grid (green electricity contract) | 0.0 | Very low | ||
Electricity self-generated and exported | ** | |||
Electricity self-generated and consumed | ** | |||
Electricity (unspecified) | ** | |||
Fuels | Natural gas (standard mix) | 0.202 | Low | |
Oil-based fuels | 0.266 | High | ||
Renewable natural gas | 0.005 | Very low | ||
Unspecified | ** | |||
Others | Biomass | ** | ||
Solar thermal | 0.0 | None | ||
Other | Water | Fresh water (municipal water supply) | ** | |
Ground water | ** | |||
Rainwater (Collected on site) | ** | |||
Reclaimed water | Very low | |||
Water supply | 0.344 | Very low | ||
Water discharge | 0.708 | ** | ||
Water consumption unspecified | Very low | |||
Waste | Incineration: hazardous | 0.021 | Very Low | |
Incineration: non-hazardous | 0.021 | Very Low | ||
Landfill: hazardous | 0.009 | Low | ||
Landfill: non- hazardous | 0.467 | Very Low | ||
Recycling: hazardous | 0.021 | Very Low | ||
Recycling: non-hazardous | 0.021 | Very Low | ||
Reuse: hazardous | 0.021 | Very Low | ||
Reuse: non- hazardous | 0.021 | Very Low | ||
Waste to energy: hazardous | 0.021 | Very Low | ||
Waste to energy: non-hazardous | 0.021 | Very Low | ||
Fugitives | Bromomethane | Methyl bromide (CH3Br) | 2.0 | Low | |
Carbon dioxide (CO₂) | 1.0 | Low | ||
Methane (CH4) | 28.0 | Medium | ||
Nitours oxide N2O | 265.0 | High | ||
R-10 Carbon tetrachloride (CCl4) | 1730.0 | Very high | ||
R-11 | CFC-11 | Trichlorofluoromethane (CC13F) | 4660.0 | Very high | ||
R-12 | CFC-12 |Dichlorofluoromethane (CCI2F2) | 10200.0 | Very high | ||
R-12B1 | Halon-1211 |1,2 Bromochlorodifluoromethane (CBrCl2F2) | 1750.0 | Very high | ||
R-13 | CFC-13 |Chlorodifluoromethane (CCIF3) | 13900.0 | Very high | ||
R-13 B1 | Halon-1301 |1,2 Bromotrifluoromethane (CBrF3) | 6290.0 | Very high | ||
R-21 | HCFC-21 |Dichlorofluoromethane (CHCI2F) | 148.0 | Medium | ||
R-22 | HCFC-22 |Chlorodifluoromethane (CHCIF2) | 1760.0 | Very high | ||
R-23 | HFC-23| | 12400.0 | Very high | ||
R-32 | HFC-32| | 677.0 | High | ||
R-41 | HFC-41| | 116.0 | High | ||
R-43-10mee | HFC-43-10mee| | 1650.0 | Very high | ||
R 114B2 | Halon-2402 |1,2 Dibromotetrafluoroethane (C2Br2F4) | 1470.0 | Very high | ||
R-115 | CFC-115 |Chloropenthafluoroethane (C2CIF5) | 7670.0 | Very high | ||
R-123 | HCFC-123 |2,2-Dichloro-1,1,1-trifluoroethane (C2CI2F3) | 79.0 | Medium | ||
R-124 | HCFC-124 |1-Chloro-1,2,2,2-tetrafluoroethane (C2CIF4) | 527.0 | High | ||
R-125 | HFC-125| | 3170.0 | Very high | ||
R-225ca | HCFC-225ca |3,3-Dichloro-1,1,1,2,2-pentafluoropropane(C3HCl2F5) | 127.0 | High | ||
R-225cb | HCFC-225cb |1,3-Dichloro-1,1,2,2,3-pentafluoropropane(C3HCl2F5) | 525.0 | High | ||
R-134 | HFC-134| | 1120.0 | Very high | ||
R-134a | HFC-134a| | 1300.0 | Very high | ||
R-140a | 1,1,1- Trichloroethane | Methyl chloroform (C2H3Cl3) | 160.0 | High | ||
R-141b | HCFC-141b |1,1-Dichloro-1-1-fluoroethane(C2H3Cl2F) | 782.0 | High | ||
R-142b | HCFC-142b |1-Chloro-1,1-difluoroethane(C2ClF2) | 1980.0 | Very high | ||
R-143 | HFC-143| | 328.0 | High | ||
R-143a | HFC-143a| | 4800.0 | Very high | ||
R-152 | HFC-152| | 16.0 | Medium | ||
R-152a | HFC-152a| | 138.0 | High | ||
R-161 | HFC-161| | 4.0 | Low | ||
R-227ea | HFC-227ea| | 3350.0 | Very high | ||
R-236cb | HFC-236cb| | 1210.0 | Very high | ||
R-236ea | HFC-236ea| | 1330.0 | Very high | ||
R-236fa | HFC-236fa| | 8060.0 | Very high | ||
R-245ca | HFC-245ca| | 716.0 | High | ||
R-245fa | HFC-245fa| | 858.0 | High | ||
R-365mfc | HFC-365mfc| | 804.0 | High | ||
Sulfur hexafluoride (SF6) | 23500.0 | Very high |
Units vary according to the type:
Energy: kgCO2e/kWh
Water: kgCO2e/cubm
Waste and Fugitive: kgCO2e/kg
**The emission factors for district heating and cooling vary from country to country. The variation also persists the countries and regions. Therefore, the impact depends on the building's geolocation and which technology is being used.
It is observed that the Emission Factor of district heating is higher in Germany as compared to Switzerland and United Kingdom. Therefore district heating has higher Impact in Germany compared to Switzerland and UK.
The electricity-specific emission factors also vary from country to country, with very small differences for some countries and very large for other countries. The variation for EF is due to the number of reasons, for example which type of fuel is used to generate electricity and which technology has been used.
In Germany, 56% of electricity is produced via conventional energy carriers such as Lignite, Hard coal, Oil and Gas and 44% via renewable energy sources like Wind, Solar, Biomass (AGEB 2023), compared to Switzerland where 62% of electricity is produced via hydropower, 29% Nuclear and 9% from conventional power plants (Swiss federal office of energy, 2021). Therefore, the electricity from grid has a higher impact in Germany compared to Switzerland.
The emission factors of oil based fuels are slightly higher than the Natural gas and Renewable natural gas, therefore oil based fuels have higher impact than Natural gas and Renewable natural gas. On the other hand, the emission factor for biomass varies according to the fuel (Wood logs, Wood Pellets, Grass/Straws). Generally, biomass has a very low emission impact.