You can't take his article as an essay. Copying his article would be Plagiarism. You should read the article, take his facts and points, understand them and rewrite it in your own words. Keep in mind that the examiner checks many papers every year probably has been doing so for quiet a while now. It's easy for a person to tell if something has been copied from somewhere or someone.

If you want to write an essay on energy crises in Pakistan what you do is: first make of list of things you know as causes and solution, then just read up on energy crises from different articles, essay, magazines, internet etc. This should give you enough knowledge about the topic. Then you can start writing it in your own words.

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-Nickfury