Updating Purchase Obligations to Deploy Affordable Resources to Energy Markets Under PURPA Act or the UPDATE PURPA Act This bill modifies (1) the Federal Energy Regulatory Commission's (FERC) rules related to cogeneration and small power production facilities, (2) the mandatory purchase obligation for electric utility companies to purchase energy from certain facilities, and (3) the one-mile rule of FERC. FERC must modify its rules regarding certain cogeneration and small power production facilities, including to require that such facilities are responsible for the costs of any facility or network upgrades associated with delivering power to its electric customers. The bill authorizes electric utility companies to waive the mandatory purchase obligation if additional power is not required to meet customers' electricity needs. The bill directs FERC to publish a final rule that allows any person or entity a rebuttable presumption to the one-mile rule. Under the one-mile rule, facilities are considered to be located at the same site as the facility for which qualification is sought if they are located within one mile of such facility. Specified factors must be taken into consideration by FERC when it determines whether two facilities are located at the same site.