Forum for ecoinvent Version 3

ecoinvent Forum Archive

Modelling an individual fuel mix with info on total fuel amount only

Written on: 02.09.2021#1

Author:
beepfish

Hi everybody,In the ecoinvent database, there are many processes for generating electricity and heat by using different energy sources. What i want to do is create a process that represents the fuel mix of a factory under study which generates electricity and heat on its own by burning different kind of fuels. The factory uses lignite, natural gas and light fuel oil.The problem is that i have data on the total amount of fuel used, but not on what part of it is converted to electricity and what part is converted to heat. If I understand the processes in the ecoinvent database correctly (e.g. "high voltage electricity, heat and power co-generation, lignite, DE" with the unit [MJ] ), then I am not getting anywhere here with the pure fuel quantity, right? I need the electrical efficiency of the plant in order to then calculate from my fuel quantity the amount of energy generated in form of heat and the amound generated in form of electricity, which allows me to use the different processes for heat or electricity generation for the respective fuel.Or is there a simpler way to model this on the basis of the fuel quantities only without any kind of efficiency information (by the way, I have data on the total fuel quantity used both in the unit t or m³ and in the unit MJ)?Thanks for any help and best regards

Written on: 07.09.2021#2

 

Dear User,

You can access the heat and power cogeneration data in the “undefined” form, i.e. before linking and allocation. You can do so by accessing ecoQuery, if you never accessed before please see here https://www.ecoinvent.org/database/how-to-use-ecoinvent-3-online/first-login-to-ecoinvent-3/first-login-to-ecoinvent-3.html. When you look for a dataset, make sure you have selected “undefined”. There you will be able to see how much fuel is used to produce the relative amounts of heat and electricity.

If you are looking at the dataset using an attributional system model (cut-off or APOS), remember that the allocation for energy is done based on exergy. You can see the allocation information by looking at the true value property recorded in the dataset (when you search in ecoQuery with the system model selected).

For more information on how to consult ecoinvent online please see our website (https://www.ecoinvent.org/database/how-to-use-ecoinvent-3-online/how-to-use-ecoinvent-3-online.html) and training webinars (https://www.ecoinvent.org/support/webinars/webinars-and-tutorials.html). This webinar in particular (https://www.youtube.com/watch?v=aXdS4ohbvIk) shows you how to navigate ecoQuery.

I hope this is of help to you.

Best regards,

Johannes Müller, Data Analyst, ecoinvent association

Written on: 08.09.2021#3

Author:
beepfish

Hello,

thank you for the kind answer, the tip to check the undefined UPR already helped a lot and I think I can work from there on.

However, this brought up a follow-up-question: I realized that in the UPRs for the cogeneration processes of natural gas, biogas and oil I can find information on the heating values (e.g. natural gas: 39 MJ/m³). In the processes for energy cogeneration using lignite or hard coal  I can't find this information.

 

Is this information missing or can I find these assumptions in some sort of report? Do you have a standarized number for these two fuels (lignite and hard coal), which was used by ecoinvent as the heating value?

 

Thank you and best regards