in this paper we showed th at e nergy as an input has a significa nt role in th e production fun ction in the diffe rent sectors o f eco nomy. ene rgy inte nsity in th e ir ani an economy has increased dramatically d ur ing 1972-94. usi ng a cobb-douglas production fu nctio n for the diltcrc nt sectors in ir an (assuming each se ctor to usc lab o r. ca pit al and e ne rgy asinput ) we showed th...