National Power Corporation v. Benguet Electric Cooperative
REITERATIONFacts
The Antecedents: National Power Corporation (NPC), a government-owned and controlled corporation, supplied electricity to Benguet Electric Cooperative, Inc. (BENECO) under a franchise agreement. They entered into a Contract of Sale of Electricity and a Transition Contract for the Supply of Electricity. NPC installed a metering system at the Irisan Substation and set a Current Transformer Ratio (CTR) with a multiplier of 5,196.31. From May 2000 to February 2004, NPC billed BENECO using this multiplier, also granting a Prompt Payment Discount (PPD) for timely payments. In February 2004, BENECO's employee discovered unusually low system losses, prompting an investigation by the National Transmission Corporation (TRANSCO). TRANSCO found that the CTR was set incorrectly, meaning BENECO had been billed at half the correct rate. NPC subsequently demanded payment for the underbilling, amounting to P157,743,314.43, and revoked BENECO's PPD. BENECO refused to pay, arguing the underbilling resulted from NPC's negligence and that NPC waived claims on older billings due to a 90-day correction period stipulated in their contract. NPC filed a complaint for injunction, damages, and other relief. Procedural History: The Regional Trial Court (RTC) of La Trinidad, Benguet, Branch 63, ruled in favor of BENECO, declaring the underbilling illegal, unjust, and unenforceable. The RTC found NPC's failure to detect the error to be negligence, holding NPC responsible for the losses, and affirmed BENECO's entitlement to the PPD. NPC's motion for reconsideration was denied. NPC appealed to the Court of Appeals (CA), which affirmed the RTC's decision, again finding NPC's gross negligence as the proximate cause of the underbilling and deleting the award of attorney's fees. NPC's subsequent motion for reconsideration was also denied. This led to the present petition before the Supreme Court. The Petition: NPC filed a Petition for Review on Certiorari under Rule 45 of the Rules of Court, assailing the CA's decision and resolution. NPC argued that BENECO was liable for the underbilling due to unjust enrichment, contending that the cited cases of Panay Electric, Ridjo Tape, and Meralco were not applicable as BENECO possessed the technical expertise to detect the metering error. NPC also asserted its right to revoke the PPD. The Supreme Court modified the CA's decision, ruling that BENECO's liability for underbilling is based on contract, not unjust enrichment. The Court held that BENECO is liable only for underbilling errors corrected within 90 days from receipt of the erroneous billings, as per Section 25 of the Transition Contract. The case was remanded to the RTC to determine the specific amount of underbilling within this period. The Court also affirmed BENECO's entitlement to the PPD, finding NPC's revocation premature.
Issue(s)
Whether BENECO's non-payment of the underbilling constitutes unjust enrichment. Whether the cases of Panay Electric Co., Inc. v. Court of Appeals, Ridjo Tape & Chemical Corp. v. Court of Appeals, and Manila Electric Company v. Spouses Chua are applicable to the case; and whether BENECO is liable for underbilling. Whether BENECO is entitled to a 3% Prompt Payment Discount (PPD).
Ruling
The petition is partly meritorious. The Court modified the CA's decision, holding BENECO liable for underbilling arising from the use of a wrong multiplier only for the period from February 17, 2004, to May 17, 2004. The case was remanded to the RTC to determine the exact amount of this liability. The Court affirmed BENECO's entitlement to the Prompt Payment Discount.
Ratio Decidendi
On the issue of unjust enrichment: The Court ruled that the principle of unjust enrichment is not applicable because a contract exists between NPC and BENECO, and their rights and obligations are governed by the provisions of their contracts, specifically the Contract of Sale of Electricity and the Transition Contract. The principle of unjust enrichment requires that the enrichment be without just or legal ground and that the claimant has no other action based on contract, quasi-contract, crime, or quasi-delict. In this case, NPC's claim for underbilling is based on contract, and the Transition Contract provides specific mechanisms for addressing billing errors. Therefore, unjust enrichment cannot be invoked as a basis for recovery. On the applicability of cited cases and BENECO's liability for underbilling: The Court found that Panay Electric, Ridjo Tape, and Meralco were not fully applicable due to factual differences and the presence of specific contractual provisions in the present case. While these cases underscore the obligation of public utilities to exercise utmost care and diligence, the Transition Contract in this case contained a specific provision (Section 25) governing billing errors and the timeframes for correction. The Court noted that in Panay Electric and Meralco, the contracts lacked specific provisions for billing errors, and in Ridjo Tape, the Service Agreement was applied. The Court reiterated the principle that public utilities must be diligent to avoid forfeiting amounts due from customers due to negligence. The Court held that BENECO is liable for underbilling, but only for the period within the 90-day correction window stipulated in Section 25 of the Transition Contract. Section 25 states that errors due to wrong reading, arithmetical mistakes, or omissions must be corrected within 90 days from the customer's receipt of the bill, otherwise the claim is waived. The Court, citing National Transmission Corporation v. Misamis Oriental I Electric Cooperative, Inc., classified the failure to use the correct multiplier as an omission. Since NPC demanded payment for underbilling from May 2000 to February 2004 on May 17, 2004, only billings received from February 17, 2004, to May 17, 2004, were within the 90-day period and thus collectible. The Court emphasized that the determination of the correct multiplier was NPC's sole responsibility, and its failure to do so for four years constituted negligence. The case was remanded to the RTC to determine the precise amount of underbilling within this limited period. On BENECO's entitlement to a Prompt Payment Discount (PPD): The Court affirmed BENECO's entitlement to the PPD. The policy statement for the PPD required full payment of the monthly bill and no unpaid accounts. Since BENECO consistently paid its current monthly bills promptly, and its liability for underbilling was disputed and undetermined at the time NPC revoked the PPD, BENECO could not be considered to have a delinquent account. The Court agreed with the CA that NPC prematurely revoked the PPD and disconnected BENECO's power supply based on a disputed deficiency assessment. NPC was bound to honor the discount as long as BENECO paid its current obligations on time.
Main Doctrine
The principle of unjust enrichment is not applicable when a contract exists between the parties and a specific remedy is provided therein. Liability for underbilling due to erroneous billings is governed by the contract's provisions on billing errors, particularly the 90-day period for correction of errors due to wrong reading, arithmetical mistakes, or omissions, unless the error is due to an inaccurate meter, which may be corrected anytime. Public utilities are expected to discharge their functions with utmost care and diligence, and cannot recover underbillings beyond the contractual period due to their own negligence.