If an energy supplier is unable to furnish an adequate supply of energy due to an emergency, an order or decision of a public regulatory body, or other acts beyond the control of the Grantee, then the Grantee shall have the right and authority to adopt reasonable rules and regulations limiting, curtailing or allocating extensions of service or supply of energy to any customers or prospective customers, and withholding the supply of energy to new customers, provided that such rules and regulations shall be uniform as applied to each class of customers or prospective customers, and shall be non-discriminatory as between communities receiving service from the Grantee.