When the state finance committee has outstanding revenue bonds, the state finance committee, with the concurrence of the director, may by resolution provide for the issuance of refunding revenue bonds with which to refund the outstanding revenue bonds, or any part thereof at maturity, or before maturity if they are by their terms or by other agreement, subject to call for prior redemption, with the right in the state finance committee to combine various series and issues of the outstanding revenue bonds by a single issue of refunding revenue bonds. The refunding bonds shall be payable only out of a special fund created out of the gross revenue of the steam electric utility, and shall only be a valid claim as against such special fund and the amount or proportion of the revenue of the utility pledged to said fund. The rate of interest on refunding revenue bonds shall not exceed the rate of interest on revenue bonds refunded thereby. The state finance committee may exchange the refunding revenue bonds for the revenue bonds which are being refunded, or it may sell them in such manner as it deems for its best interest. Except as specifically provided in this section, the refunding revenue bonds shall be issued in accordance with the provisions contained in RCW 43.21A.610 through 43.21A.642 with respect to revenue bonds.