Most facility operators can tell you their electricity rate per kilowatt-hour. Far fewer can tell you their demand charge — even though for many commercial and industrial buildings, it's the larger of the two line items on the bill.
That gap matters. You can't manage a cost you can't see, and demand charges are structured in a way that makes them easy to overlook and expensive to ignore.
What a demand charge actually measures
Utilities bill commercial and industrial customers on two different things: the total energy consumed over the billing period, measured in kilowatt-hours, and the highest rate of draw at any single point during that period, measured in kilowatts.
That second number is the demand charge. It's typically calculated from the highest 15- or 30-minute interval of electricity use in the entire billing cycle — one brief spike, not an average. A facility that runs quietly all month and then draws hard for twenty minutes gets billed as if that twenty-minute peak defined the whole month, because for demand-charge purposes, it does.
Energy charges scale with how much you use. Demand charges scale with how hard you draw, at your single worst moment, regardless of how brief.
This is different from how most people intuitively think about a utility bill.
Why this creates outsized exposure for certain facilities
Not every building is equally exposed. Demand-charge risk concentrates wherever a facility has load that starts and stops sharply, rather than running at a steady, predictable level.
A distribution center's demand often spikes at shift change, when dock equipment, conveyor systems, and vehicle charging all draw at once. A facility with continuous refrigeration carries a high baseline that compressor cycling can push higher still. A data center's load is dense and constant, which raises the baseline demand charge even without a dramatic spike. A hotel's HVAC and kitchen equipment can create a sharp peak during a single high-occupancy morning. A multi-tenant retail property may have a demand profile driven by whichever tenant's equipment happens to cycle on at the same time as everyone else's. See how this varies by facility type.
In each case, the building's demand charge is being set by a narrow slice of time that may not represent normal operations at all — and that single slice determines a fixed cost for the entire billing period.
Why it's easy to underestimate
Three things make demand-charge exposure harder to see than it should be.
It's buried in a single line item
Most utility bills show one dollar figure for demand charges without breaking out which interval set it, or how close the facility came to a lower peak on other days. Without that detail, there's no way to tell whether last month's number was typical or an outlier.
It resets every month
A facility that has a bad peak once can carry that cost forward as the new baseline for demand-charge ratchets in some utility territories, where the billed demand can't drop below a percentage of the historical peak for up to a year. One unusual day can quietly set costs for months afterward.
It doesn't show up in walk-throughs
A facility can look efficient — modern equipment, reasonable total consumption — and still carry a large demand charge, because efficiency and peak behavior are not the same thing. A facility can be efficient and still spike hard for twenty minutes a month.
What it takes to actually find out
Getting a real answer requires interval data, not just the monthly bill total. Most utilities can provide 15-minute interval usage data on request, and that data shows exactly when a facility's peak occurred, how high it was, and how it compares to the rest of the month. That's the starting point for any serious assessment — not an estimate based on square footage or equipment lists, but a look at what a facility actually did over time.
From there, the useful questions are specific:
- What set last month's peak, and is it likely to repeat?
- How does the billed demand compare to the facility's typical operating level?
- Is a ratchet clause in effect, and if so, for how long does a single peak affect billing?
- Would shifting equipment schedules, staging shift-change loads, or adding battery storage meaningfully change the number — and does the potential savings justify the cost of doing something about it?
That last question is where a lot of facilities stop short. Not every building with a high demand charge has an economical fix. The only way to know is to run the numbers on the specific facility, against its specific interval data — not a generic industry benchmark.
Where this fits into a broader energy strategy
Demand-charge management is one piece of a facility's overall energy picture, alongside the underlying supply contract, on-site generation, and how those pieces interact. Addressing demand charges without also checking the supply contract behind them — or vice versa — tends to leave money on the table somewhere in the stack. Worked examples of how those pieces combine are set out in the industrial and hospitality engagement economics.
TEK Energy is an independent energy advisory and systems integrator. We don't sell equipment or supply contracts. We evaluate a facility's actual interval data, determine where the exposure is real versus assumed, and — where the numbers support it — structure and oversee whatever combination of storage, procurement, or infrastructure investment addresses it.