# How to model load or energy losses in a process

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Dear Team,

I am trying to build a model of gradle-to-grave LCA for transformer, and do not know how to model the use phase of a transformer. It is suggested that the main environmental impact at this stage comes from energy losses (load and non-load losses of transformer), I have data on the losses experessed in kW, but not sure what flows need to be included to represent energy loss, and should it go to Input or Output? Do I understand it correctly that I can use energy flows (as an Input or Output?), but first transform the known power value into energy metric?
in openLCA
by (100 points)
Hello  katesi1990 , I am interested if you solved this issue. I am trying to model the use stage of the transformer and also not sure what flows and parameters (of needed) to include. I would appreciate if you can suggest. thanks

## 1 Answer

+1 vote
by (2.5k points)
You could certainly model energy losses as emitted heat if that's important to your system. I would expect though that the primary reason why this loss is important is because it requires inputs upstream when the loss is greater. That is, for your process you may have 1.1 units entering to produce 1 net unit. Because of that loss, creating that extra 10% will have 10% greater impacts upstream
by (130 points)
Thank you! As for the usage of 1.1 unit energy as an input and 1 unit energy as output, I have some concern in using such "cumulative" value instead of using the "extracted" energy loss value. Since the transformer itself only "transforms" the energy from one voltage to another, 99.8% energy enetering the transformer, will leave it and flow further to the next station in energy grid. In other words, is it correct to encounter the overall energy, if biggest portion of it is kind of a product that will leave the system?

My current solution is as follows (could you check and give your comment?):
1. Calculated the amount of energy loss throughout the use-phase life of transformer using a well-known formula.
2. Modeled the use phase of transformer using calculated amount of energy (divided into fractions depending on energy mix at location) as an imput.
3. For output I only used a dummy flow "transformer used". In other words, the environmental impact at transformer use phase would consist of impacts of producing the energy itself.

Shall I still add the emitted heat as an output of this process?