First, you can define your "Functional Unit" as 1 kWh of electricity and since you're mixing 10% biomass and 90% coal, then 0.1 kWh would be generated from the biomass burning and 0.9 kWh will be generated from the coal burning.

Since SimaPro EcoInvent database has models for electricity production from coal and from biomass, then can easily obtain the emissions from both fuels. Multiply biomass emissions by 0.1 and coal emissions by 0.9 and sum up the results.

I teach this LCA and LCIA in my following courses at Yale University:

Khalil, Y.F. (2016). Green Energy Systems (GES), ENVT S-105. Yale College and Yale School of Engineering & Applied Science, New Haven, CT 06520

Khalil, Y.F. (2016). Environmental Risk Assessment (ERA). Yale School of Forestry & Environmental Studies, F&ES-889.

Hope this helps answer your question.

Professor Yehia Khalil, Yale University, USA

Fellow of the University of Oxford, United Kingdom

Respected Dr. Khalil,

Thank you very much for your answer. i have one more question regarding your answer: i want to consider a case for direct cofiring in same combustion unit , is it still same way to that ?

I appreciate your help.

Hi Iqbal,

The method I gave you in the simplest way since you said you're still learning this software.

Another method is to use the case for coal burning which is included in the EcoInvent database in SimaPro and then create a new input stream for the biomass and reducing the mass of coal for the balance. I hope that you can manage doing that since the method more experience than the first method.

Hope this helps answer your question.

Professor Yehia Khalil, Yale University, USA

Fellow of the University of Oxford, United Kingdom

Respected Sir,

Thanks for your valuable suggestions.