### Monte Carlo & parameter variation of product streams

Posted:

**20 Jun 2016 11:17**Hello,

I am modelling bioenergy systems in which outputs are dependent on uncertain input variables (e.g. biomass compositon).

I am currently struggeling to account for uncertainties related to product streams or parameterized product streams:

Let's say the model of interest consists of a single process with 2 products (A&B) and an elementary flow entering the system (E_in, e.g. resources) and an elementary flow leaving the system (E_out, e.g. emission).

The monte carlo analysis accounts for uncertainties that are defined for E_in and E_out.

However, as far as I found out, openLCA is not able to account for uncertainties related to each product (A & B), as calculated allocation factors remain fixed.

To do so, allocation factors need to be calculated for each run of the monte carlo simulation to account for differing quantities of products.

Another option, parameter variation, seems not to help either:

A paramter variation could help to test a couple of different variants. Using parameter variation (in a project) does not help either as allocation factors remain fixed...

So the only way as see at the moment is to copy all processes affected and to change parameters manually first and update allocation factors afterwards.

This very time consuming and means that the parameter variation and uncertainty analysis, as implemented in openLCA, is not suitable to account for uncertain or parameterized product streams.

Is there any way to solve this problem?

I am modelling bioenergy systems in which outputs are dependent on uncertain input variables (e.g. biomass compositon).

I am currently struggeling to account for uncertainties related to product streams or parameterized product streams:

Let's say the model of interest consists of a single process with 2 products (A&B) and an elementary flow entering the system (E_in, e.g. resources) and an elementary flow leaving the system (E_out, e.g. emission).

The monte carlo analysis accounts for uncertainties that are defined for E_in and E_out.

However, as far as I found out, openLCA is not able to account for uncertainties related to each product (A & B), as calculated allocation factors remain fixed.

To do so, allocation factors need to be calculated for each run of the monte carlo simulation to account for differing quantities of products.

Another option, parameter variation, seems not to help either:

A paramter variation could help to test a couple of different variants. Using parameter variation (in a project) does not help either as allocation factors remain fixed...

So the only way as see at the moment is to copy all processes affected and to change parameters manually first and update allocation factors afterwards.

This very time consuming and means that the parameter variation and uncertainty analysis, as implemented in openLCA, is not suitable to account for uncertain or parameterized product streams.

Is there any way to solve this problem?