California Code, Public Utilities Code - PUC § 12825

(a) A district furnishing light, heat, or power may engage in activities to reduce wasteful, uneconomical or unnecessary uses of energy, including, but not limited to, public information programs, the sale of insulation, the sale, rental and lease of materials or equipment for the purpose of conserving energy or reducing the need for the installation of electric generating facilities, and the adoption of voluntary and mandatory load management programs, and may also engage in activities to accelerate and participate in the development of alternative sources of energy including, but not limited to, the supply of equipment for use in connection therewith, and may do all things necessary or convenient to the full exercise of the powers herein granted. The interest rates charged on extended payment contracts for such materials or equipment shall not exceed that necessary to cover the district's full cost of money plus its administrative costs and anticipated losses due to nonpayment on such contracts.

(b) This section does not constitute a change in, but is declaratory of, the existing law.