Opinion by
This writ оf error is directed to a Mesa County district court judgment which reversed a Public Utilities Commission decision. We will refer to the plaintiffs in error as the Commission or Public Service and to the defendant in error as Grand Valley.
In 1965 Public Service received a request for electric service for a motel which was planned to be built on the outskirts of Grand Junction. It was anticipated that the motel would require approximately 196 kilowatts, and in reliance on this request Public Service constructed an extension from its nearest line approximately 1.25 miles in order to serve the construction needs of the motel. Shortly thereafter, Grand Vallеy filed a complaint with the Commission alleging that Public Service had unlawfully constructed the extension. Although the Commission originally found for Grand Valley and ordered Public Service to remove the extension line, motion for rehearing was granted by the Commission, which then reversed its decision and held that the extension had been lawfully constructed under a certificate granted to Public Service in its decision No. 27071. Grand Valley then appealed to the district court, which reversed the Commission’s decision under review and ordered the prior decision of the Commission reinstated.
Resolution of this case revolves around the legal effect to be given the 1946 decision of the Commission, P.U.C. No. 27071. That decision resulted in a Certificate of *260 Public Convenience and Necessity being granted to Public Service in order to ratify and clarify its rights in the Grand Junction District. The pertinent language of the 1946 decision is as fоllows:
“* * * provided, however, that said (Respondent’s) [Public Service] authorization to extend its lines and service is granted without prejudice to the right of Grand Valley (Petitioner) now serving certain rural districts in said area, to make available its electricаl service without duplication of facilities or service by Respondent, to residents of said rural area living within that part of sаid Grand Junction District which lies in Mesa County, who are not now served by Respondent or Petitioner, except such individuals * * * whose seрarate estimated electric power requirements at any one time exceed one hundred kilowatts * * * and said individuals, etc. having a separate electrical power requirement at any one time in excess of 100 kilowatts are to be served by Rеspondent * *
It is clear that the certificate in relevant part provides that Public Service has the right to make extensiоns to its present lines except when it would conflict with the right of Grand Valley to serve certain designated rural areas within the District. The prohibition imposed on Public Service, however, did not apply to customers whose estimated needs exceeded 100 kilowatts. The Certificate specifically provides that those customers whose needs at any one time were “in еxcess of 100 kilowatts are to be served by Public Service Company, without duplication of facilities, or service by Grand Valley Rural Power Lines, Inc. * * *”
The Commission in its decision held that this Certificate granted Public Service the right to construct the extension in question and that Grand Valley’s certificate specifically excluded service by it of power in excess of 100 kilowatts in the subject area.
Grand Valley attacks the Commission’s decision on several grounds. It argues that the Commission
*261
could not have intended thе 1946 certificate to grant Public Service a
permanent
right to serve those customers with greater than a 100 kilowatt need, especiаlly in light of the changed conditions since 1946. Grand Valley cites no authority, and we are not aware of any, that a portion of the order of the Commission becomes unlawful by the mere operation of time. It must be remembered that the proceеding before the Commission was not one to reopen the decision granting the 1946 certificate. Since rights granted under a cеrtificate of authority are property rights, due process requires a full hearing if anything granted in the certificate is to be tаken away. At such a hearing conceivably there might be grounds to modify the 1946 certificate. As to whether the 1946 certificate grаnted the authority to Public Service to function in the disputed area, we believe that the Commission is the proper authority tо interpret its own certificate.
Westway Motor Freight, Inc. v. Public Utilities Commission,
Grand Valley also argues that, even if the 1946 certificate is valid and aрplicable, Public Service’s right to serve the motel does not accrue until the construction is complete and the motel showed an actual need of more than 100 kilowatts of electricity. However, in this respect, it should be noted that the 1946 certificate precluded Grand Valley from serving customers whose estimated needs exceeded 100 kilowatts. Since an existing need mаy be accurately metered, the use of the term “estimated” implies that an anticipated need may serve as a рroper basis for an extension. One contem *262 plating construction also is entitled to know to what utility it can make its demand for service in advance of completion of construction.
Grand Valley finally argues that this court’s decision in
Public Utilities Commission v. Home Light and Power Company,
The judgment is reversed.
Mr. Chief Justice Moore and Mr. Justice Hodges concur.