Each board may issue and sell revenue bonds and general obligation bonds for the purchase, construction, reconstruction, equipping, demolition, or alteration of capital assets, including accessibility barrier elimination project costs and abatement of environmental hazards as such terms are defined in section 79-10,110, and the acquisition of sites, rights-of-way, easements, improvements, or appurtenances and other facilities connected with the operation of the community colleges. Each board may establish in its budget a capital improvement and bond sinking fund. Such fund shall be used (1) first for the retirement of bonds assumed by the board in accordance with the provisions of such bonds, (2) then for (a) renewal work and deferred maintenance as defined in section 81-173, (b) handicapped access and life safety improvements made to existing structures or grounds including accessibility barrier elimination project costs and abatement of environmental hazards as such terms are defined in section 79-10,110, and (c) projects designed to prevent or correct a waste of energy, including measures taken to utilize alternate energy sources, all in accordance with the capital facilities plan of the community college area, (3) then for the retirement of bonds issued pursuant to this section, and (4) then for the purchasing, purchasing on contract, constructing, and improving of facilities necessary to carry out sections 85-1501 to 85-1540. Revenue bonds issued shall be subject to sections 85-1520 to 85-1527. No general obligation bonds shall be issued without the approval by a majority vote of the qualified electors of the community college area voting in an election called for such purpose pursuant to section 85-1518. No bonds issued under sections 85-1501 to 85-1540 shall be an obligation of the State of Nebraska, and no state tax shall be levied to raise funds for the payment thereof or interest thereon.