Different results between Monte Carlo and Quick Results

Question

I am currently doing an uncertainty analysis for my product system by using Monte Carlo. To do this I removed all uncertainty from the ecoinvent database and thus when I currently run the Monte Carlo I only get one value with no standard deviation. However, this one value is VERY different from the results I get from Quick results, which does not make sense. Should I not get the same value from quick results and Monte Carlo when there is no uncertainty in my system? It seems I get the same value when using Cut-Off but not when using Consequential database, but I cannot see what should make one work and not the other. I have attached pictures for a random ecoinvent process - one being results from the Monte Carlo and the other is the quick result for the same process.

 

Comments

I would double-check the allocation scheme you use to generate the different results. I'm not sure if the consequential analysis requires you to use "No allocation" or something else.

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I just double checked and the allocation method is None on both. I also tried using different allocation methods but the results still differed between quick results and Monte Carlo.