Negative value of degree of autonomy
The value of degree of autonomy (DOA) comes out negative when there is only DSO source of electricity. Theoretically, according to the following definition of DOA, when my consumption is completely satisfied with the DSO electricity, the DOA should be 0. However, because of the efficiency of the transformers, there is more consumption from DSO than the electricity need. This is a reason the DOA is coming out to be negative.

Checklist to make sure that the bug report is complete:
- [x] OS: Winows, 10
- [x] Branch: dev, updated on 22-02-2021
- [ ] If applicable: Attach full error message
- [x] If applicable: Share screenshots/images of your problem
- [ ] If applicable: Share used input data
@TheOneAndra @Bachibouzouk I would like to address this issue of negative value of degree of autonomy.
Thanks @paragpatil39! I personally would say that we can leave this as is, but add a note in the DOA definition.
The simple solution to avoid negative DOA would be to not have conversion assets with efficiencies between the energy provider sources and the demands. Of course, when the system grows more complex, this can not be solved easily anymore.
The value of degree of autonomy (DOA) comes out negative when there is only DSO source of electricity.
The negative DOA can also occur when the DSO is the main source of electricity but still not the only one:
This system resulted in a DOA = -0.066 .(Last column is the aggregated flow).

We can close this with a validity check in E.