Section 16. If the department is of opinion, after a hearing had upon its own motion or upon complaint, that the regulations, practices, equipment, appliances or service of any common carrier are unjust, unreasonable, unsafe, improper or inadequate, the department shall determine the just, reasonable, safe, adequate and proper regulations and practices thereafter to be in force and to be observed, and the equipment, appliances and service thereafter to be used, and shall fix and prescribe the same by order to be served upon every common carrier to be bound thereby. The department may after such a hearing, order any railway company to build and operate any just and reasonable extensions of its lines for which it may have been or may be granted locations and order from time to time that a railroad company shall operate its lines, of standard gauge, or such parts thereof as the department shall prescribe, by electric power instead of steam power, and in its order shall prescribe the time within which the work of electrification shall be done. Before making such order, the department shall consider the relative importance and necessity of the changes in any specific regulations, practices, equipment and appliances proposed to be included therein and of other changes which may be brought to its attention in the course of the hearing, the financial ability of the carrier to comply with the requirements of the order, and the effect of the carrier's compliance therewith, upon its financial ability to make such other changes, if any, as may be deemed by the department of equal or greater importance and necessity in the performance of the service which the carrier has professed to render to the public. Every such common carrier shall obey every requirement of every such order so served upon it, and do everything necessary or proper in order to secure absolute compliance with every such order by all its officers, agents and employees. Every such common carrier, railroad or railway company shall submit evidence to the department within thirty days after such order is served upon it that it has complied, or is in the process of complying, with such order. The two preceding sentences shall not be applicable to any particular order issued under this section pending any appeal from such order.