Gulf oil & gas disaster, lobbyists, Obama & huge threat of natural gas (methane) to Humanity & Biosphere
3 August 2010, 08:21, by Dr Gideon Polya
Methane (CH4) has a molecular weight of 16 and carbon dioxide (CO2) has a molecular weight of 44.
When you burn CH4 you get CO2: CH4 + 2O2 -> CO2 + 2 H2O.
Accordingly burning 16 tonnes of CH4 yields 44 tonnes of CO2 and burning 100 tonnes of CH4 yields 100x 44/16 = 275 tonnes of CO2.
However if there is industrial leakage of CH4 (estimated to be at least 2.2% by the US EPA) then one must consider the greenhouse gas effect of the released methane (72 times worse than CO2 as a greenhouse gas on a 20 year time scale).
Of our 100 tonnes of CH4, how much CH4 leakage (y tonnes) gives the same greenhouse effect (in CO2 equivalents or CO2-e) as burning the remaining CH4?
y tonnes CH4 x (72 tonnes CO2-e/tonne CH4) = (100-y) tonnes CH4 x (2.75 tonnes CO2-e/ tonne CH4).
72y tonnes CO2-e = (100-y) 2.75 tonnes CO2-e
72y = 275 – 2.75y
74.75y = 275
y = 275/74.75 = 3.68 i.e. a 3.7% leakage of CH4 yields that same greenhouse effect as burning the remaining CH4.
Check.
3.68 tonnes leaked CH4 corresponds to 3.68 tonnes CH4 x 72 tonnes CO2-e/ tonne CH4 = 265 tonnes CO2-e .
Burning the remaining 96.32 tonnes of CH4 corresponds to 96.32 tonnes CH4 x 2.75 tonnes CO2/tonne CH4 = 265 tonnes CO2.
Methane (CH4) has a molecular weight of 16 and carbon dioxide (CO2) has a molecular weight of 44.
When you burn CH4 you get CO2: CH4 + 2O2 -> CO2 + 2 H2O.
Accordingly burning 16 tonnes of CH4 yields 44 tonnes of CO2 and burning 100 tonnes of CH4 yields 100x 44/16 = 275 tonnes of CO2.
However if there is industrial leakage of CH4 (estimated to be at least 2.2% by the US EPA) then one must consider the greenhouse gas effect of the released methane (72 times worse than CO2 as a greenhouse gas on a 20 year time scale).
Of our 100 tonnes of CH4, how much CH4 leakage (y tonnes) gives the same greenhouse effect (in CO2 equivalents or CO2-e) as burning the remaining CH4?
y tonnes CH4 x (72 tonnes CO2-e/tonne CH4) = (100-y) tonnes CH4 x (2.75 tonnes CO2-e/ tonne CH4).
72y tonnes CO2-e = (100-y) 2.75 tonnes CO2-e
72y = 275 – 2.75y
74.75y = 275
y = 275/74.75 = 3.68 i.e. a 3.7% leakage of CH4 yields that same greenhouse effect as burning the remaining CH4.
Check.
3.68 tonnes leaked CH4 corresponds to 3.68 tonnes CH4 x 72 tonnes CO2-e/ tonne CH4 = 265 tonnes CO2-e .
Burning the remaining 96.32 tonnes of CH4 corresponds to 96.32 tonnes CH4 x 2.75 tonnes CO2/tonne CH4 = 265 tonnes CO2.