2 ms·

> Even if fossil LNG is used, it releases less CO2 per unit energy. However released methane has a significantly worse greenhouse effect than CO2 (80x over 20

by masklinn 10mo ago

> Even if fossil LNG is used, it releases less CO2 per unit energy. However released methane has a significantly worse greenhouse effect than CO2 (80x over 20 years, 28 over 100, 8 over 500 — this decreases because methane has an atmospheric lifetime of 12 years and decays to CO2). So leakage in the LNG chain is a massive problem.

mr_toad 10mo ago
Jet engines don’t release the methane, they burn it, and they’re very efficient. And jets don’t leak fuel, that would be very hazardous.
- masklinn 10mo ago
  LNG is not a nice liquid at room temp, so more use means more in transit and more complicated supply chains, meaning more leaks.
akoboldfrying 10mo ago
Right, but are leakage rates high enough to make this a concern? Every methane molecule leaked is a methane molecule not burnt, so there's already a strong profit maximisation incentive to leak as little as possible (even before considering loftier goals like workplace safety or externally imposed regulation).
- masklinn 10mo ago
  > Right, but are leakage rates high enough to make this a concern? According to a recent IEA report, 30% of the LMG supply chain’s greenhouse impact is methane leaks. > there's already a strong profit maximisation incentive to leak as little as possible That runs against the stronger profit maximisation incentive of doing as little maintenance and being as cheap as possible.
api 10mo ago
A major difference is: there is an economic incentive to not leak methane since a leak is wasted fuel, while the economic incentive for CO2 is to make more of it.
- masklinn 10mo ago
  > A major difference is: there is an economic incentive to not leak methane since a leak is wasted fuel That economic incentive only goes so far given the entire point of the discussion: LNG is cheap. Per the IEA's recent "Assessing Emissions from LNG Supply and Abatement Options": > Our analysis estimates total GHG emissions from the LNG supply chain are around 350 million tonnes of carbon dioxide equivalent (Mt CO2-eq) (this excludes emissions from combustion of the natural gas at the point of use). Around 70% of this is in the form of CO2 emissions which are either combusted or vented, and the remaining 30% is methane that escapes, unburnt, into the atmosphere. > ... > Globally, the average GHG emissions intensity of delivered LNG is just under 20 g CO2-eq/MJ, compared with an average of 12 g CO2/MJ for natural gas supply overall.

mr_toad 10mo ago

Jet engines don’t release the methane, they burn it, and they’re very efficient. And jets don’t leak fuel, that would be very hazardous.

masklinn 10mo ago
LNG is not a nice liquid at room temp, so more use means more in transit and more complicated supply chains, meaning more leaks.

akoboldfrying 10mo ago

Right, but are leakage rates high enough to make this a concern? Every methane molecule leaked is a methane molecule not burnt, so there's already a strong profit maximisation incentive to leak as little as possible (even before considering loftier goals like workplace safety or externally imposed regulation).

masklinn 10mo ago
> Right, but are leakage rates high enough to make this a concern? According to a recent IEA report, 30% of the LMG supply chain’s greenhouse impact is methane leaks. > there's already a strong profit maximisation incentive to leak as little as possible That runs against the stronger profit maximisation incentive of doing as little maintenance and being as cheap as possible.

api 10mo ago

A major difference is: there is an economic incentive to not leak methane since a leak is wasted fuel, while the economic incentive for CO2 is to make more of it.

masklinn 10mo ago
> A major difference is: there is an economic incentive to not leak methane since a leak is wasted fuel That economic incentive only goes so far given the entire point of the discussion: LNG is cheap. Per the IEA's recent "Assessing Emissions from LNG Supply and Abatement Options": > Our analysis estimates total GHG emissions from the LNG supply chain are around 350 million tonnes of carbon dioxide equivalent (Mt CO2-eq) (this excludes emissions from combustion of the natural gas at the point of use). Around 70% of this is in the form of CO2 emissions which are either combusted or vented, and the remaining 30% is methane that escapes, unburnt, into the atmosphere. > ... > Globally, the average GHG emissions intensity of delivered LNG is just under 20 g CO2-eq/MJ, compared with an average of 12 g CO2/MJ for natural gas supply overall.