26 Del. C. § 208

(a) (1) The Commission may, after hearing, upon notice, by order in writing, require every public utility to make, keep, and preserve for such periods of time, such accounts, records of cost accounting procedures, correspondence, memoranda, papers, books and other records as the Commission may by rules and regulations or order prescribe as necessary or appropriate for purposes of the administration of this chapter. The Commission may prescribe systems of accounts and records to be kept by public utilities, or may classify public utilities and prescribe a system of accounts and records for each class, and the manner and form in which such accounts and records shall be kept.

(2) The accounting system of any public utility also subject to the jurisdiction of a federal regulatory body shall correspond, as far as practicable, to the system prescribed by such federal regulatory body. The Commission may require any such public utility to keep and maintain supplemental or additional accounts to those required by any such regulatory body.

(3) The Commission, after notice and opportunity for hearing, may determine by order the accounts in which particular expenditures and receipts shall be entered, charged or credited.

(b) Every public utility shall keep such books, accounts, papers, records and memoranda, as are required by the Commission, in an office within this State, and shall not remove the same, or any of them, from this State, except upon such terms and conditions as may be prescribed by the Commission. Such public utility, when required by the Commission, shall furnish to the Commission, within such reasonable time as it shall fix, certified copies of its books, accounts, papers, records and memoranda, relating to the business done by such public utility within this State.