Half-hourly (HH) meter guide for UK businesses

What a half-hourly meter is

A half-hourly (HH) electricity meter records your consumption in 30-minute intervals and sends the data automatically to your supplier for settlement. HH meters carry profile class 00 (electricity) and are read remotely — no manual meter reads needed.

Your site typically becomes HH if your maximum demand exceeds 100 kVA, or if it's already flagged by the Distribution Network Operator as HH-required. Since 2017 all new commercial connections above 100 kVA have been HH by default.

Why HH pricing is different

HH tariffs price your consumption against the actual wholesale market for each 30-minute period, plus DUoS (Distribution Use of System) charges that vary by time of day. It's more granular than SME rates and gives sharp buyers a genuine chance to save through load-shifting.

• Time-of-use unit rates (day / night / weekend or full 48-period)
• Availability / capacity charges based on your agreed kVA
• Reactive power charges if your power factor is poor
• Triad avoidance opportunities (for very large users)

How to procure an HH contract

HH procurement should always be tendered — the difference between the cheapest and most expensive HH quote from the same panel is routinely 15-25%. A broker with a whole-of-panel HH desk (like Energy Tariff) can also review your capacity level and power factor at renewal.