How should i rewrite the sentence "i consider tv as one of the greatest scientific achievements of our times" using noun form of consider in place of it

Hmm. Not sure if this is right, but you could do this using idioms. I slightly altered your original sentence.

"To take into/Taking into consideration (my opinion) that TV is one of the greatest scientific achievements of our times..."

Or "In consideration of the fact that TV is one of the greatest scientific achievements of our times..."

A possible alternative, "The/My consideration that TV is one of the greatest scientific achievements of our times" may not be grammatically wrong, but it sounds weird.

"After due consideration, in my opinion TV is one of the greatest scientific achievements of our time."

after due consideration : this is a set phrase, and very often used in formal writing

The expression is 'of our time' not 'of our timeS'.