None of the provisions of this title shall apply to the generation, transmission or distribution of electricity, to the manufacture or distribution of gas, to the furnishing or distribution of water, or to the production, delivery or furnishing of steam for heat or power by a producer who is not otherwise a utility, for the sole use of such producer, or for the use of tenants of such producer, nor shall they apply to any person not otherwise a utility who manufactures and supplies such products to a utility for its use or distribution without participation by such manufacturer in such use or distribution.