What is the difference between Performance Evaluation and Competency Evaluation methodologies?

Great question, One describes a skill (technical or financial) and the other the behavior (team orientated or customer focused).
Competency based evaluation is also based on actual experiences.

Dear Mourad Nasr El-Din, Performance Evaluation methodology focuses on the work performance of the individual.
It mainly answers - how has the person performed the tasks which have been assigned to him.
Competency is the ability of an individual to do a task - It deals with the knowledge, behavior and skills required to perform a task.
Competency Evaluation methodologies is an assessment of the key attributes, a person should possess, in order to do his job well.

Performance Evaluation methodology focuses on the work performance of the individual. It mainly answers - how has the person performed the tasks which have been assigned to him. Competency is the ability of an individual to do a task - It deals with the knowledge, behavior and skills required to perform a task. Competency Evaluation methodologies is an assessment of the key attributes, a person should possess, in order to do his job well.

Performance on the job is determined by the combined answers to three questions: what to do (tasks, targets of the job), how to do (the competencies), and need to do (the motivation).
So performance evaluation is inclusive of competency evaluation.

Dear Mourad, Thank you for your valuable question.
Let's differentiate first between competences and Performance.
Competence is a combination of employee's Knowledge, Skills and Attitude.
Performance is the result of employee's work.
We can consider the competence as the input and the performance as the output.
The methodology of measuring the competencies is the Competencies' Manual which evaluate the employee's behavior against a predefined scale for every competence.
  The methodology of measuring the performance is the performance appraisal forms and systems including: a) Management By Objectives.
b)360 Appraisal Form or computer system.
c) Critical Incidents Form.
d) Assessment Centers Evaluation.
e) Ranking method.
f) Comparison method.
g) Inforced ratios.
h) ......
I hope my answer is clear.
Regards, Moh.
Yousry Allam, MBA

Thanks Deepika - Peter, and I think that we should to observing the competencies during evaluating the performance to answers - in which way the objectives has been achieved?