Southwestern Public Service Co. filed on Dec. 7 an unopposed stipulation that resolves all issues related to its ongoing rate case with the Public Utility Commission of Texas.

The stipulation provides a base rate increase of $35.2 million, retroactive to July 20, to recover a revenue requirement of $545 million, according to the filing. An administrative law judge approved interim rates, subject to refund and based on the stipulation, to become effective Dec. 10.

The Xcel Energy Inc. subsidiary originally requested in February a rate increase of $71.9 million, based on a 10.25% return on equity. The PUCT staff recommended in August a rate increase of $32.9 million.

The total impact of the stipulation is estimated to be $51.8 million, including power factor revenues of $12.6 million and rate case expenses to be addressed in a separate proceeding of $4 million. Signatories to the stipulation also agreed to place a $19 million cap on the additional annual revenues SPS can recover in its next transmission cost recovery factor application, but will not disallow any requested capital additions.

There will also be no restriction on filing future rate cases or rate riders, SPS said.

SPS expects the commission to issue a final order regarding the stipulation in the first quarter of 2017. (Docket No. 45524)