Phoenix Journal · Kitchen Operations
Shared sites bury energy in a single communal bill - extraction running flat out, refrigeration, make-up air and air conditioning all fighting each other. Here is where the money actually goes, and the levers that move it.
In a dark kitchen, energy is the bill nobody can see clearly. Several brands cook under one roof, on shared extraction, shared refrigeration and shared cooling, and it all lands in a single communal charge that gets divided up at the end of the month. Because no one operator owns the meter, no one operator feels the cost of leaving the system running flat out - and the bill climbs. Here is where that money actually goes, and the levers that bring it down.
A conventional restaurant has one cookline and one operator who feels every kilowatt. A dark kitchen stacks multiple cooklines into one building, often running close to round the clock to feed delivery demand across breakfast, lunch and late-night. The extraction has to move air for all of them, the refrigeration never sleeps, and the air conditioning spends the whole day fighting the heat the cooking throws off. Those three loads - extraction, refrigeration and cooling - are where most of a shared kitchen's energy disappears, and they feed each other: the harder the cooking, the more heat the AC has to remove, the longer everything runs.
Before cutting anything, it helps to know what you are cutting. In most shared kitchens the communal energy bill breaks down into a handful of big, continuous loads:
The pattern to notice is that these loads are linked. Heat that is not extracted becomes heat the air conditioning pays to remove and heat the fridges pay to resist. Tackle the source - the cooking heat and the systems that should be clearing it - and the savings cascade.
The structural issue in a shared kitchen is allocation. When the energy bill arrives as one number and is split by floor area, by a flat per-unit fee, or by a rough estimate, the operator who runs efficiently subsidises the one who leaves everything blazing. Nobody is rewarded for switching off, so nobody does.
The fix is to make the invisible visible. Sub-metering individual units, or at least the major shared systems, turns a communal guess into an itemised cost and changes behaviour overnight - because now waste has a name on it. Even a simple split that separates always-on shared services (extraction, lighting, refrigeration) from each unit's own cooking load gives operators something they can actually manage. You cannot cut what you cannot see.
None of these require a refit. In rough order of payback:
If the communal bill is the problem, the fastest route into it is the heat. Ventilation that matches demand, extraction that is clean enough to move air efficiently, and refrigeration that is not fighting a hot room - those three address the largest continuous loads and the way they compound each other. Sub-metering then keeps the gains honest by putting a number against each unit, so the operator who runs lean is no longer paying for the one who does not.
None of it is glamorous and none of it needs a rebuild. It is mostly maintenance, scheduling and visibility - which is exactly why it tends to get left, and exactly why it is where the easy money is.
Questions
Yes, indirectly but measurably. A grease-loaded canopy, filter set and fan move less air for the same power and leave more heat in the kitchen, which the air conditioning then pays to remove. A degreased system draws less and lightens the cooling load behind it.
Sub-metering individual units, or at least separating always-on shared services from each unit's cooking load, turns a communal guess into an itemised cost. It is the single change that most reliably changes behaviour, because waste finally has a name against it.
A system that ramps extract fan speed to the actual cooking load rather than running flat out all day. Because ventilation is often the largest controllable load in a shared kitchen, matching it to demand can take a significant slice off the bill.
Phoenix Duct Clean · by the numbers
A grease-clogged system runs hotter and draws more power. We degrease canopy, filters and fan to TR19 Grease, so your extraction - and the air conditioning fighting it - work less. UK-wide, overnight.