sounds ok except your sentence is rather long and a normal reader will tend to forget what has been said in the begining while reaching the end in my opinion the intro should remain least controversial and plain because anyone hitting the page would ber already familiar somewhat with the concept i do not think that the article should be ambitious to give the total jnan in one go the introduction in its present form fulfils that purpose all about the various forms of energy and its conservation follows almost immediatly and one must not feel so insecure about losing the reader brevity is the key