• 164 views | 3 messages Discussion: LEAP
    Topic: Does LEAP can distribute GHG mitigations among measures that interact ?Subscribe | Previous | Next
  • Jean-baptiste Brette 5/19/2021

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    Dear Madam, Sir,

    I am presently working on a project aiming at identifying priority greenhouse gases mitigation measures. In my case, the modeled mitigation scenario will include 2 measures those GHG mitigations will interact during various decades in the future: electricity generation de-carbonation (on supply side) and electrical energy efficiency measures (on demand side). Of course, this mitigation scenario is compared to a baseline scenario.

    Distributing resulting GHG mitigations between those two measures is not trivial. Some, for example, use Log Mean Divisia Index (LMDI).

    Do you know if there is a "built-in" functionality in LEAP that allow for distributing mitigations to each of the two measures of the example I described ? Or is it necessary, for example, to modeled intermediate scenarios using one measure at a a time and then export in excel to calculate such distribution of mitigations ?

    I thank you for any precision you would take time to give me.

    Best regards,
    Jean
  • Charlie Heaps 5/19/2021
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    Hi Jean-Baptiste,

    This is a great question! In LEAP you can model measures individually vs. a counterfactual baseline scenario and/or incrementally (e.g. so as to plot a MACC curve). You can also combine measures together to see how they interact with each other over time (which is really the main point of doing integrated energy system analysis).

    We don't yet have any built-in functions that automatically take the results from an integrated analysis and allocate the credit for any reductions back to individual measures. I have to say that I am not familiar with the LMDI method you listed. I would be very interested to know more about it though! Could you point me to any good descriptions of it? Depending on the method, it may be possible for you to export results from LEAP and then do such an analysis in Excel, R or similar. It may even be possible to do it within LEAP using LEAP's built-in expressions and Indicator branches. You might also consider automating things with LEAP's API.

    But either way, this idea sounds very interesting!

    Hope to hear back from you with more info!

    Best,

    Charlie
  • Jean-baptiste Brette 6/16/2021
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    Hello Charles

    Thanks a lot for your prompt answer, and sorry for answering so late on my side.

    I found elements about Log Mean Divisia Index in a French report called "Trajectoires de transition bas carbone au moindre co�t" THEMA study from the French "Minist�re de l'Environnement, de l'Energie et de la Mer" from november 2016 those contributors are Baptiste Perrissin Fabert and Alexis Foussard. You will easily find it on the internet. It is in French but you can find the formulas of LMDI method (P. 19) with explanations that could be translated easily. All the more, this work refers to a precedent work of Kesicki & Anandarajah (2011) that you can also find on research paper websites. I haven't looked at this last one in close details so far.

    Briefly summarized, emission calculation is the sum of the product of 4 factors: activity, energetic intensity, energy emissions, and techno share. Based on this, mitigating measures can be the result of an evolution of each of those factor like : lower use of a kind of technology, better efficiency, less emission intensive technology ... Then the final formula using the log functions (don't ask me why so far) gives you the mitigation due to each of those measures if there are applied all at a time.

    As I feel it so far, it could be possible to use LEAP for correctly equilibrating scenarios (demand/supply) along time, and then try to extract from the results the four factors mentioned in LMDI to redistribute correctly, with the log formula, mitigation among measures afterwards.

    A related questioning I have now, and maybe you know more than I do, is: what should be the emission factor of electric vehicles when calculating their mitigation ? It seems not pure math questioning.

    If we stick to IPCC inventory nomenclature it leads me to think that this factor should be 0. But I am wondering if other methodologies wouldn't be considering the electrical mix emission factor. Or even more confusing:

    As renewable energy is usually called an "enabling measure" for mitigating using electric vehicles I am wondering if emission factor corresponding only to renewable energy generation could be used for quantifying electrical vehicle mitigation measure and justifying this by: "some share of renewable energy have been especially developed in the view to transfer oil vehicle to electric vehicle, so the electrons generated by this oversupply of renewable energy are virtually dedicated to electric vehicles". If on a "physicist" point of view it does not make sense, it is defendable using a "political approach". And therefore, again, leads to another methodology for accounting for electric vehicle emission mitigation.

    I know it sounds a bit out of topic but if anyone would have any short comment or source to refer to, to clarify this they are welcome.

    Bye

    Jean