Estimating carbon dioxide emissions from gas plants
| Part of the Global Gas Plant Tracker, a Global Energy Monitor project. |
| Related categories: |
The following factors are used to estimate the CO2 emissions from gas-fired power plants:
- Plant capacity
- Plant capacity factor
- Lifecycle emissions factor for a gas-fired power plant
- Lifetime of a gas plant
Formula
The CO2 emissions from a gas plant can be calculated with the following formula:
Annual CO2 equivalent emissions (in million tonnes/year) = capacity (MW) * capacity factor (%) * lifecycle emissions factor (t CO2/kWh) * 1e6 g/1 t * 1 GW/1000 MW * 8760 hours/year * 1e6 kWh/1 GWh
The total lifetime CO2 emissions from a gas plant can be calculated with the following formula:
Lifetime CO2 equivalent emissions (in million tonnes) = Annual CO2 equivalent emissions (in million tonnes/year) * lifetime of gas plant
Capacity Factor
"Capacity factor" or "load factor," is a measure of the amount of power that a plant produces compared with the amount it would produce if operated at its rated capacity nonstop. A capacity factor of 100% means that a plant is run at its maximum capacity for every hour of the year. Actual capacity factors are lower than 100% because of routine maintenance, fuel availability problems, and variations in demand.
Capacity factor can be calculated as follows:
Capacity Factor (%) = [Generation (GWh) * 1 year/8760 h] / Capacity (GW)
For the Global Gas Plant Tracker, a country-level (or in some cases, regional) capacity factor is used in calculating the CO2 emissions.
The latest gas power generation published by Ember is used for the capacity factor calculation. In some cases, generation data reported is not available for the latest year. For example, for countries where 2021 data is unavailable, 2020 gas power generation is used. Operating capacity at the country-level is taken from GEM's latest available Global Gas Plant Tracker.
Regional Capacity Factor
Regional capacity factors are shown in Table 1 below with the following inputs:
- GEM's February 2023 Global Gas Plant Tracker data
- Ember's yearly electricity data release (January 31, 2023 version)
Table 1: Regional Capacity Factors Calculated for Global Gas Plant Tracker
| Region | GEM Operating Capacity (MW) | Ember Power Generation (TWh) | Weighted Average Capacity Factor (%) |
| Africa | 106,746 | 337 | 35.99% |
| Americas | 659,236 | 2,135 | 36.97% |
| Asia | 739,417 | 2,626 | 40.55% |
| Europe | 317,602 | 1,197 | 43.04% |
| Oceania | 16,531 | 50 | 34.59% |
| Global Total | 1,839,532 | 6,346 | 39.38% |
As a comparison, the International Energy Agency (IEA) in their 2021 World Energy Outlook (Table A.3a) reports:
| Global gas power production | 6,257 TWh |
| Global gas power capacity | 1,822 GW |
| Global capacity factor | 39.20% |
Country Level Capacity Factor
Country level capacity factors are shown in Table 2 below with the following inputs:
- GEM's February 2023 Global Gas Plant Tracker data
- Ember's yearly electricity data release (January 31, 2023 version)
- In cases where country level capacity factors were inaccurate (ie: greater than 100% or large variation between regional and country level capacity factor) the regional capacity factor was assumed for the CO2 emissions calculation.
Table 2: Country-level Capacity Factors Calculated for Global Gas Plant Tracker
| Country | Region | GEM Operating Capacity (MW) | Ember Generation data year | Country Capacity Factor (%) | Regional Capacity Factor (%) | Use Regional or Country level Capacity Factor? |
| United States | Americas | 531,307 | 2021 | 33.93% | 34.02% | country |
| China | Asia | 108,980 | 2021 | 28.55% | 41.28% | country |
| Russia | Europe | 107,815 | 2021 | 49.37% | 46.83% | country |
| Japan | Asia | 77,679 | 2021 | 49.47% | 41.28% | country |
| Iran | Asia | 69,938 | 2021 | 47.06% | 38.84% | country |
| Saudi Arabia | Asia | 62,952 | 2021 | 39.16% | 38.84% | country |
| Egypt | Africa | 48,502 | 2021 | 36.03% | 38.84% | country |
| Mexico | Americas | 43,904 | 2021 | 51.85% | 52.58% | country |
| Italy | Europe | 43,691 | 2022 | 36.93% | 38.92% | country |
| South Korea | Asia | 42,321 | 2021 | 47.24% | 41.28% | country |
| United Arab Emirates | Asia | 41,608 | 2021 | 34.88% | 38.84% | country |
| Thailand | Asia | 36,113 | 2021 | 38.11% | 41.66% | country |
| United Kingdom | Europe | 33,384 | 2021 | 42.26% | 45.94% | country |
| Iraq | Asia | 30,707 | 2021 | 28.09% | 38.84% | country |
| Spain | Europe | 26,942 | 2022 | 36.86% | 38.92% | country |
| India | Asia | 26,497 | 2021 | 27.65% | 36.45% | country |
| Germany | Europe | 24,886 | 2022 | 44.10% | 38.92% | country |
| Türkiye | Asia | 24,262 | 2021 | 51.85% | 45.94% | country |
| Canada | Americas | 22,965 | 2021 | 35.93% | 34.02% | country |
| Algeria | Africa | 22,308 | 2021 | 38.53% | 38.84% | country |
| Argentina | Americas | 21,961 | 2021 | 46.26% | 52.58% | country |
| Indonesia | Asia | 19,769 | 2021 | 32.49% | 41.66% | country |
| Kuwait | Asia | 19,361 | 2021 | 41.96% | 38.84% | country |
| Taiwan | Asia | 17,882 | 2021 | 69.65% | 41.28% | country |
| Malaysia | Asia | 17,443 | 2021 | 41.46% | 41.66% | country |
| Pakistan | Asia | 16,353 | 2021 | 38.71% | 36.45% | country |
| Australia | Oceania | 14,608 | 2021 | 34.35% | 34.59% | country |
| Brazil | Americas | 14,378 | 2021 | 72.28% | 52.58% | country |
| Netherlands | Europe | 14,043 | 2022 | 38.21% | 38.92% | country |
| Oman | Asia | 13,432 | 2021 | 30.94% | 38.84% | country |
| Uzbekistan | Asia | 13,122 | 2021 | 38.10% | 46.83% | country |
| Qatar | Asia | 12,277 | 2021 | 44.13% | 38.84% | country |
| Israel | Asia | 12,230 | 2021 | 44.91% | 38.84% | country |
| Libya | Africa | 11,682 | 2021 | 30.29% | 38.84% | country |
| Bangladesh | Asia | 11,519 | 2021 | 54.44% | 36.45% | country |
| Nigeria | Africa | 10,388 | 2021 | 24.99% | 33.91% | country |
| Singapore | Asia | 10,354 | 2021 | 55.98% | 41.66% | country |
| France | Europe | 8,815 | 2022 | 55.68% | 38.92% | country |
| Bahrain | Asia | 8,543 | 2021 | 42.39% | 38.84% | country |
| Belarus | Europe | 8,310 | 2021 | 50.53% | 45.94% | country |
| Vietnam | Asia | 8,146 | 2020 | 47.58% | 41.66% | country |
| Turkmenistan | Asia | 6,947 | 2021 | 26.06% | 46.83% | country |
| Syria | Asia | 6,026 | 2020 | 18.36% | 38.84% | regional |
| Tunisia | Africa | 5,783 | 2021 | 39.34% | 38.84% | country |
| Belgium | Europe | 5,626 | 2022 | 46.91% | 38.92% | country |
| Greece | Europe | 5,594 | 2022 | 39.92% | 38.92% | country |
| Peru | Americas | 5,070 | 2021 | 40.73% | 52.58% | country |
| Austria | Europe | 4,744 | 2022 | 28.30% | 38.92% | country |
| Chile | Americas | 4,737 | 2021 | 34.92% | 52.58% | country |
| Azerbaijan | Asia | 4,612 | 2021 | 40.49% | 46.83% | country |
| Ireland | Europe | 4,407 | 2022 | 42.66% | 38.92% | country |
| Hong Kong | Asia | 4,239 | 2021 | 38.78% | 41.28% | country |
| Portugal | Europe | 4,211 | 2022 | 47.06% | 38.92% | country |
| Kazakhstan | Asia | 4,015 | 2021 | 64.29% | 46.83% | country |
| Colombia | Americas | 3,716 | 2021 | 36.43% | 52.58% | country |
| Poland | Europe | 3,155 | 2022 | 45.63% | 38.92% | country |
| Jordan | Asia | 3,149 | 2021 | 54.59% | 38.84% | country |
| Ghana | Africa | 3,059 | 2021 | 37.80% | 33.91% | country |
| Hungary | Europe | 3,030 | 2022 | 33.39% | 38.92% | country |
| Venezuela | Americas | 2,910 | 2020 | 124.04% | 52.58% | regional |
| Romania | Europe | 2,903 | 2022 | 39.09% | 38.92% | country |
| Finland | Europe | 2,592 | 2022 | 5.28% | 38.92% | regional |
| Ukraine | Europe | 2,332 | 2021 | 47.78% | 45.94% | country |
| Philippines | Asia | 2,065 | 2020 | 80.05% | 41.66% | regional |
| Trinidad and Tobago | Americas | 1,993 | 2021 | 42.56% | 52.58% | country |
| Bolivia | Americas | 1,938 | 2021 | 36.34% | 52.58% | country |
| New Zealand | Oceania | 1,923 | 2021 | 36.45% | 34.59% | country |
| Dominican Republic | Americas | 1,678 | 2020 | 41.02% | 52.58% | country |
| Myanmar | Asia | 1,674 | 2021 | 54.70% | 41.66% | country |
| Czech Republic | Europe | 1,659 | 2020 | 47.27% | 38.92% | country |
| Armenia | Asia | 1,386 | 2021 | 26.19% | 46.83% | country |
| Lebanon | Asia | 1,200 | 2021 | 108.35% | 38.84% | regional |
| Lithuania | Europe | 1,148 | 2022 | 6.07% | 38.92% | regional |
| Georgia | Asia | 1,142 | 2021 | 23.79% | 46.83% | country |
| Latvia | Europe | 1,087 | 2022 | 14.81% | 38.92% | regional |
| Côte d'Ivoire | Africa | 1,079 | 2020 | 54.80% | 33.91% | regional |
| Slovakia | Europe | 1,001 | 2022 | 24.98% | 38.92% | country |
| Moldova | Europe | 968 | 2021 | 29.48% | 45.94% | country |
| Croatia | Europe | 911 | 2022 | 45.50% | 38.92% | country |
| Denmark | Europe | 895 | 2022 | 13.13% | 38.92% | regional |
| Morocco | Africa | 870 | 2021 | 64.03% | 38.84% | regional |
| Uruguay | Americas | 840 | 2021 | 42.81% | 52.58% | country |
| Bulgaria | Europe | 780 | 2022 | 42.59% | 38.92% | country |
| Angola | Africa | 720 | 2021 | 61.68% | 33.91% | regional |
| Norway | Europe | 603 | 2021 | 5.49% | 45.94% | regional |
| Yemen | Asia | 600 | 2021 | 19.22% | 38.84% | regional |
| Serbia | Europe | 549 | 2021 | 10.60% | 45.94% | regional |
| Republic of the Congo | Africa | 534 | 2020 | 54.30% | 33.91% | regional |
| Cuba | Americas | 486 | 2021 | 46.04% | 52.58% | country |
| Jamaica | Americas | 464 | 2021 | 36.66% | 52.58% | country |
| Senegal | Africa | 436 | 2021 | 47.39% | 33.91% | country |
| Slovenia | Europe | 421 | 2022 | 12.74% | 38.92% | regional |
| Panama | Americas | 381 | 2021 | 18.58% | 52.58% | regional |
| El Salvador | Americas | 378 | 2021 | 0.00% | 52.58% | regional |
| Sudan | Africa | 374 | 2020 | 50.97% | 38.84% | country |
| Sweden | Europe | 350 | 2022 | 9.46% | 38.92% | regional |
| Sri Lanka | Asia | 300 | 2021 | 0.00% | 36.45% | regional |
| South Africa | Africa | 280 | 2021 | 0.00% | 33.91% | regional |
| Mozambique | Africa | 246 | 2021 | 114.16% | 33.91% | regional |
| Tanzania | Africa | 240 | 2020 | 89.90% | 33.91% | regional |
| North Macedonia | Europe | 230 | 2021 | 56.58% | 45.94% | country |
| Brunei | Asia | 212 | 2020 | 113.08% | 41.66% | regional |
| Malta | Europe | 205 | 2022 | 101.35% | 38.92% | regional |
| Mauritania | Africa | 180 | 2021 | 0.00% | 38.84% | regional |
| Estonia | Europe | 173 | 2022 | 2.64% | 38.92% | regional |
| Palestine | Asia | 140 | 2020 | 23.65% | 38.84% | regional |
| Macao | Asia | 136 | 2021 | 49.52% | 41.28% | country |
| Ecuador | Americas | 130 | 2021 | 101.86% | 52.58% | regional |
| Isle of Man | Europe | 87 | N/A | N/A | 45.94% | regional |
| Tajikistan | Asia | 86 | 2021 | 35.84% | 46.83% | country |
| Togo | Africa | 65 | 2021 | 0.00% | 33.91% | regional |
| Switzerland | Europe | 55 | 2021 | 0.00% | 45.94% | regional |
Lifecycle emissions factor
The Global Gas Plant Tracker assumes the median lifecycle emissions as reported in the IPCC 5th Assessment Report Annex 3 (2014)[1] of 490 g CO2eq/kWh for a Combined Cycle (CC) gas-fired power plant.
This lifecycle emissions estimate is in line with other reported values, such as:
- A natural gas combined cycle plant can emit 403–513 g CO2 eq/kWh from a life cycle perspective, 2021 UNECE Report, Carbon Neutrality in the UNECE Region: Integrated Life-cycle Assessment of Electricity Sources.[2]
- A natural gas combined cycle plant has a life cycle emissions range of 410-650 g CO2 eq/kWh.[3]
- A natural gas combined cycle life cycle emissions range of 306 - 681 g CO2 eq/kWh.[4]
- A natural gas combustion turbine life cycle emissions range of 487 - 987 g CO2 eq/kWh.[5]
- A natural gas combined cycle life cycle emissions of 499.1 g CO2 eq/kWh.[6]
Lifetime of Gas Plant
Lifetime CO2 estimates by GEM's Global Gas Plant Tracker assume gas plants operate over a 30 year lifetime[7], and 5 years for plants older than 30 years.
Limitations
The following are limitations with the CO2 emissions estimates calculated in GEM's Global Gas Plant Tracker:
- Generation data (from Ember) used to calculate country-level capacity factor often lags GEM's Global Gas Plant Tracker data, which is updated twice yearly. For example, the latest generation for a country may be for 2020, but the operating capacity is taken from GEM's February 2023 data release.
- Lifecycle emissions factor assumes constant value for all gas plant technologies. An older gas turbine or steam turbine gas plant may have higher lifecycle emissions than a newer combined cycle gas plant.
- Capacity factor is applied at the country level, not asset level. Depending on the use of the gas plant (ie: peaker vs. baseload) the actual capacity factor at the asset level may vary.
Articles and Resources
References
- ↑ "IPCC 5th Assessment Report, Annex III, Technology-specific Cost and Performance Parameters" (PDF). Intergovernmental Panel on Climate Change (IPCC). Retrieved August 25, 2022.
{{cite web}}: line feed character in|title=at position 68 (help)CS1 maint: url-status (link) - ↑ "Carbon Neutrality in the UNECE Region: Integrated Life-cycle Assessment of Electricity Sources" (PDF). United Nations Economic Commission for Europe. 2021.
{{cite web}}: line feed character in|title=at position 39 (help)CS1 maint: url-status (link) - ↑ "Climate Change 2014: Mitigation of Climate Change. Contribution of Working Group III to the Fifth Assessment Report of the Intergovernmental Panel on Climate Change" (PDF).
{{cite web}}: line feed character in|title=at position 92 (help)CS1 maint: url-status (link) - ↑ "The role of natural gas and its infrastructure in mitigating greenhouse gas emissions, improving regional air quality, and renewable resource integration". Progress in Energy and Combustion Science. 64. 2018-01-01. doi:10.1016/j.pecs.2017.10.002. ISSN 0360-1285.
- ↑ "The role of natural gas and its infrastructure in mitigating greenhouse gas emissions, improving regional air quality, and renewable resource integration". Progress in Energy and Combustion Science. 64. 2018-01-01. doi:10.1016/j.pecs.2017.10.002. ISSN 0360-1285.
- ↑ "Life Cycle Assessment of a Natural Gas Combined-Cycle Power Generation System" (PDF). National Renewable Energy Laboratory.
{{cite web}}: CS1 maint: url-status (link) - ↑ "Combined-Cycle Plant Life Assessment" (PDF). Sargent & Lundy.
{{cite web}}: CS1 maint: url-status (link)
