Surplus capacity in transmission facilities owned by any other power agency shall be made available for transmitting and delivering electric energy to any Nebraska power agency. Electrical energy shall be transmitted and delivered over the transmission facilities by any power agency subject to the terms of sections 70-625.02 and 70-626.01 to 70-626.04 but only upon payment of rates, tolls, and charges that are reasonable, fair, and nondiscriminatory for the use made of the transmission facilities of the power agency.