Revenue and Taxation Code § 40044
CHAPTER 3. Special Provisions and Exemptions
When an electric utility purchases electrical energy and pools in its system the energy with electrical energy generated by it, the consumption of electrical energy in this state from the pool by the utility during any quarter shall be deemed to be a consumption of energy generated by it to the extent that the kilowatt-hours of the electrical energy generated by it during the quarter exceeds the kilowatt-hours consumed by the electric utility.