Cal. Rev. & Tax. Code § 40010
"Electric utility" means any person engaged in producing, generating, transmitting, furnishing, distributing or delivering electrical energy for sale without regard to whether the person is subject to regulation or is regulated by the Public Utilities Commission. The term does not include a person who generates electrical energy or redistributes electrical energy solely for his own use or for the use of his tenants and not for sale to others.
When the board determines that it is necessary for the efficient administration of this part, the board may regard any person not primarily engaged in the business of selling electrical energy who purchases electrical energy for distribution to others as a consumer and not as an electric utility.
Ca. Rev. and Tax. Code § 40010