Phoenix Journal · Energy & Cost
Peak demand charges hide two different costs: when you use power, and how much you draw at once. A busy kitchen is exposed to both because service sits in the grid's dearest window. Here is how to flatten the peak.
Peak demand charges are one of the most confusing lines on a commercial electricity bill, partly because two different things hide under the phrase. One is about when you use power; the other is about how much you draw at once. A busy kitchen is unusually exposed to both, because its heaviest hour tends to coincide with the grid's most expensive window. The good news is that most of the levers are operational, not capital - once you can see where the charges come from.
The first is time-of-use. Distribution network charges (DUoS) split the day into red, amber and green bands, with the red band - typically weekday early evenings, roughly 4pm to 7pm - carrying by far the highest unit rate, sometimes many times the overnight rate. As market-wide half-hourly settlement rolls out through 2026, when you draw power matters more than ever. The second is capacity. Sites with a half-hourly meter agree a maximum import capacity in kVA with their network operator and pay a fixed charge on that agreed figure every month, whether they use it or not - plus penalty charges if they exceed it. Network charges as a whole are rising sharply from April 2026, so both of these are getting more expensive, not less.
Here is the awkward truth: your peak is dinner service, and dinner service sits squarely in the red band. You cannot move when people want to eat, so the cooking load itself is largely fixed. That is exactly why the wins come from everything around the cooking rather than the cooking itself:
Every kilowatt you take off the always-on background load is a kilowatt you are not paying red-band rates for during service. Two of the largest continuous loads in a kitchen are refrigeration and ventilation, and both respond well. Demand-controlled kitchen ventilation, which ramps extract fans to the actual cooking load instead of running flat out, takes a meaningful slice off the peak as well as the total - part of the wider case for cutting ventilation running costs. Well-maintained refrigeration draws less to hold temperature. Trimming the base load shrinks both the height of your peak and the capacity you need to support it.
None of this is visible until you look. Reading your consumption profile - ideally half-hourly - shows exactly which half-hours are driving the red-band spend and the recorded maximum demand, which is the same discipline as learning to read a commercial energy bill and find waste. You cannot flatten a peak you have never seen.
Start by seeing the shape of your demand, then attack it in order: stagger start-up so nothing spikes unnecessarily, shift every flexible load you can out of the red band, right-size the agreed capacity you are paying for, and trim the always-on base load that inflates the peak underneath service. If your power factor is poor you may also be paying reactive-power charges that correction can remove. Almost all of this is scheduling and housekeeping rather than capital spend - which is why peak demand charges, intimidating as they look on the bill, are one of the more controllable costs in the building.
Questions
Two separate things. Time-of-use distribution charges (DUoS) make electricity used in the weekday early-evening red band - roughly 4pm to 7pm - much dearer than off-peak. Separately, half-hourly metered sites pay a fixed capacity charge on the maximum import capacity (kVA) they agree with their network operator, plus penalties for exceeding it. A busy kitchen is exposed to both because service coincides with the red band.
By working on everything around the cooking. Stagger equipment start-up so you do not spike by firing everything up at once, which lowers your maximum demand and can let you reduce your agreed kVA capacity. Shift flexible loads - warewashing, water heating, ice-making, refrigeration defrost, EV charging - out of the red band. And trim the always-on base load from refrigeration and ventilation, which sits underneath the peak.
Quite possibly. Half-hourly sites pay a fixed monthly charge on their agreed maximum import capacity in kVA regardless of what they actually draw. Many kitchens hold a capacity figure set years ago that is well above their real recorded maximum demand. If so, your network operator can usually reduce the agreed capacity, and the fixed charge falls with it - though exceeding capacity brings penalties, so it needs to be set with real data.
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