NG to LPG - why are feedstock transmission emissions zero?

Hi,

Could someone please explain to me why the feedstock transmission emissions for the NG to LPG case in the Upstream Results HHV tab are zero? In the latest GHGenius model, in cell N12 the emission factor is manually typed in as zero. How can there be no emission associated with piping the gas from the field to the plant gate where the gas will then be separated out into C3+ or C2+.

From practical experience, there should be emissions associated with running the compression equipment along the pipeline route along with any associated fugitive methane emissions that are released.

I am trying to calculate the upstream GHG emissions associated with producing natural gas in AB, fractionating the propane out in Fort Saskatchewan, and transporting it via rail ~ 3,000 km.

Thanks for the help!

Hi Don,

Thanks for your response. I am still unclear as to how the model treats the upstream emissions from the plant gate for natural gas. Am I right to conclude that there are no emission factors in the model for taking gas from the wellhead to the fractionator?

If so, the number you included in your response (1.5 g/km), is this per GJ of natural gas? and is this a CO2 eq number? if so which GWP potential is used to generate this number? Thank you for your help!

Hi Don,

Would you be able to tell me the following:
1) Where I can find this 1.03 g CO2 eq/GJ-km in the model?
2) If it is too complicated, could you please provide the GHG emission profile broken down by component? (CO2, CH4, CO, N20) I am looking for the emission profile broken out by component as my model has various GWP optionalities built into it.

Thank you for your help!
Zsolt