Hi myrto,
I understand that you want to add a generator in "MATPOWER" with a cost of $20,000 on bus 9.
To achieve this, you can refer to the following discussion link, which provides insights on how to add generators to different buses in "MATPOWER" and view the power flow results.
By following the steps mentioned in the discussion, you will be able to add the desired generator to bus 9 with the specified cost.
Thanks,
Akash.