(a) If steam produced primarily for generating electricity is utilized in electric operations for other purposes or by another operating department subject to the jurisdiction of the commission, the entire cost shall be charged in the first instance to the operating expense accounts provided herein for cost of steam production, and the amount applicable to the steam transferred, including repairs and depreciation, shall be credited to account 705, Steam Transferred—Cr.

(b) If another operating department subject to the jurisdiction of the commission is charged with any amount in addition to that which is credited to account 705, Steam Transferred—Cr., in accordance with subdivision (a), such additional amount shall be credited to account 621, Rent from Electric Property.

(c) Steam supplied by the municipal electric utility to the operating municipality (including any function or department thereof except those which are under the jurisdiction of the commission) shall be credited to account 622, Miscellaneous Electric Revenues, at the cost of production. When the amount received for such service is greater or less than such cost, the difference shall be credited or charged, as the case may be, to account 280, Contributions—Operating Municipality.