Retrospective electricity tariff revision permitted, but higher-than-standard bulk rates need specific statutory justification.

A statutory power to revise electricity charges may operate retrospectively where the amended language and purpose indicate that rates can be refixed from the date payment first became due after commencement, and different rates may be applied for different periods if the relevant statutory factors are considered. On the facts, the higher levy above the general HV-2 tariff was not justified because the appellant's supply did not disclose any special circumstance warranting a charge above the bulk consumer rate. The operative principle is that retrospective tariff revision is permissible, but any higher differential must be supported by the statutory criteria and specific justification.

---

---

Issues: (i) whether the amended power to revise electricity charges under Section 60(5)(a) could operate retrospectively from 20.5.1983 and permit rates different from the general HV-2 tariff; (ii) whether, on the facts, there was justification to charge the appellant at rates higher than the HV-2 rates applicable to other bulk consumers.

Issue (i): whether the amended power to revise electricity charges under Section 60(5)(a) could operate retrospectively from 20.5.1983 and permit rates different from the general HV-2 tariff.

Analysis: The amended provision was intended to free the parties from the constraints of an old contract and empower the authorities to revise rates by taking into account the relevant statutory factors. The language of the provision supported revision from the date on which payment first became due after the commencement date, and the power was not confined to prospective operation only. The section also did not bar the fixing of different rates for different periods, provided the statutory factors were considered.

Conclusion: The revised rates could validly operate retrospectively from 20.5.1983, and the authorities were not barred from fixing rates different from the general tariff.

Issue (ii): whether, on the facts, there was justification to charge the appellant at rates higher than the HV-2 rates applicable to other bulk consumers.

Analysis: The appellant had enjoyed concessional supply for many years, but the special circumstances relied upon had lost force with the passage of time. At the same time, the Board's reasons for charging above HV-2 rates were not accepted as sufficient, since the appellant's supply was already treated differently in material respects and there was no special reason to burden it above the general bulk consumer tariff. The statutory factors, including the nature of supply, the purpose for which it was required, and the relevant circumstances of the appellant, did not justify a higher levy.

Conclusion: No justification was shown for charging more than the HV-2 rates; the appellant was entitled to be charged at the HV-2 rates applicable to other consumers.

Final Conclusion: The challenged tariff revisions were sustained only to the extent that retrospective re-fixation was permissible, but the levy above HV-2 rates was set aside and the appellant's liability was confined to the HV-2 tariff for the relevant period.

Ratio Decidendi: A statutory power to revise contractual electricity tariffs may operate retrospectively where the language and purpose of the provision so indicate, but the revised tariff must still be fixed by reference to the relevant statutory factors and cannot be justified at a higher level absent special circumstances.

---