Rajesh Gupta 5/4/2015

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Dear Taylor,
As mentioned in another post (http://www.energycommunity.org/default.asp?action=9&read=1778&fid=22), in accordance with the IPCC guidelines LEAP assumes that biogenic CO2 emissions from biomass or wood, are compensated by the CO2 captured during the grow period of the biomass, in that sense the emissions from biomass are neutral. Still, in my calculation the biogenic CO2 emission from wood is non-zero. It is not clear, what are the assumptions that LEAP uses to calculate biogenic CO2 emission from wood or biomass. Any information in this regard would be appreciated. Thanks!

Taylor Binnington 5/4/2015
 

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Hi Rajesh,

First - it's possible to assign *non*-biogenic CO2 emissions to a branch which consumes wood or biomass. However, the default emissions factors for wood and biomass fuels include an emission factor for biogenic CO2, the assumption being that the resource is sustainably harvested.

Second - I think you may be confusing CO2 emissions with global warming potential (GWP). If you assign a biogenic CO2 emission factor, you will see non-zero biogenic CO2 emissions. However, the GWP (measured in equivalent mass of non-biogenic CO2) from such an emission will be zero.

Just to ensure that all of the relevant environmental effects (of all pollutants) are being calculated, I would recommend that you visit the General: Results Variables to Save screen form LEAP's main menu, and enable calculation of all results under the 'Energy Sector Environmental Loadings' heading.

Hope this helps,

Taylor

Rajesh Gupta 5/4/2015
 

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Thanks much Taylor, I have now enabled all the relevant environmental effects for calculation. Just to make sure that I have understood you clearly:

1) I can choose to have this assumption that the resource is not harvested sustainably by assigning *non*-biogenic CO2 emissions to wood or biomass, right? How can I assign non-biogenic CO2 emissions to wood or biomass - I guess by simply adding it as new effect?

2) You are right, I was indeed confused CO2 emissions with GWP. So the actual GHG emissions are presented by results from - "Environment: All Effects" (and NOT by GWP results)?

3) Can I see the GHG emission results by branches (e.g. cooking, lighting and appliances)? When I choose to see the GHG emission results by branches it only shows GWP results and NOT the results that come from choosing -"Environment-All Effects".

Thanks for your patience!

Taylor Binnington 5/4/2015
 

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Hi Rajesh,

1) Correct - you would just add a new emission factor.

2) Partly correct - this result shows mess emissions of all pollutants, not just those which are GHGs.

3) Some of the Results view settings are not 'sticky', meaning that you may have to re-select the exact result you would like to view, upon changing which data are displayed (for example, when you switch from displaying by fuel to displaying by branches).

Hope this helps,

Taylor

Rajesh Gupta 5/4/2015
 

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Hi Taylor,
Thanks for the clarifications. Whenever I display the result by other than 'Effects', it separates the results in biogenic and non-biogenic CO2 emissions. I am not able to see the two emission results together in one chart (when display by other than 'Effects') but I can have them in two separate charts. Is it because LEAP does not lump the two emissions (biogenic & non-biogenic) together as biogenic could or could not have GWP (that is the resource is sustainably harvested or not is an issue)?

Taylor Binnington 5/12/2015
 

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Hi Rajesh,

I don't totally understand your question. When you display Environment: All Effects, by Effects, you should be able to see each of the separate pollutants shown on the same chart.

When you display the global warming potential, there should be no contribution from biogenic carbon dioxide.

Taylor