Somebody has proposed selling you something to reduce your demand charge, or you have noticed a large kilowatt line on the bill and want to know whether it is worth doing anything about. That is two questions, and they have to be answered in order.
Said plainly first. We reconcile commercial bills to filed tariffs, and the tariff we have reconciled is ComEd's in northern Illinois. We hold no Ohio ratebook and this page quotes no Ohio rate. Every number below is one you read off your own bill.
What a demand charge is measuring, and why it is not usage
Your energy charge is billed on everything you used across the month, in kilowatt hours. Your demand charge is billed on the single highest interval in the month, in kilowatts.
That is the whole distinction and it is the reason the charge feels arbitrary. You can run a careful operation for thirty days and one afternoon where the compressor, the chillers, and a second line all happen to be running in the same fifteen minutes writes the number. The bill does not remember the other thirty days.
Ohio commercial accounts on the larger delivery classes carry that charge inside the regulated delivery half of the bill, which is set by your utility's filed tariff and is not something a generation supplier can quote you out of.
Question one: how big a share is it actually
Before anything else, size it. Your bill shows a billed demand figure in kilowatts and a rate in dollars per kilowatt. Multiply them. That is the demand charge in dollars for that month. Divide by the bill total.
Run that for twelve months, because the number moves with the season and a single winter bill will understate a summer problem badly.
If demand comes back as a small share of the total, you have your answer and it costs nothing further: the money on your bill is in energy and the fixed delivery components, and equipment sold to shave peaks is attacking the wrong line. That is a real result and it is the one nobody selling equipment will produce for you.
Question two: is the peak short or is it your normal operation
A demand charge that is a large share is only attackable if the peak that sets it is brief. If your building simply runs near its maximum most of the working day, there is nothing to shave, because shaving means moving load out of an interval and there is no emptier interval to move it into.
There is a rough read on this from the bill alone, and it needs no software. Take the kilowatt hours for the month and divide by the billed kilowatts, then divide again by the number of hours in the billing period. That ratio is your load factor: how close your average draw runs to your peak draw.
A ratio near the top of the range means a flat, heavily utilised building. The peak is your normal operation, and shaving it means changing what the business does rather than when it does it. A low ratio means the opposite: your average is far below your peak, so the peak is a spike, and a spike is a thing that can be moved, staggered, or absorbed.
That single division changes what any proposal in front of you is worth, and it uses two numbers that are already printed on the bill.
What the bill still cannot tell you
It cannot tell you which interval set the peak, or what was running when it did. The bill preserves the maximum and discards the fourteen hundred readings that produced it. Load factor tells you whether a spike exists; only the interval record behind the bill tells you when it happened and whether it recurs.
That is the honest boundary of what a bill can settle, and it is worth knowing where it falls before anyone quotes you a solution to a problem that has not been located yet.
How do I calculate my demand charge in Ohio?
Multiply the billed demand in kilowatts on your bill by the dollars-per-kilowatt rate on the same bill. The result is that month's demand charge. Compare it to the bill total to see what share of your cost it represents, and repeat across twelve months because it is seasonal.
Is a demand charge always worth reducing?
No. It is worth reducing only when it is a meaningful share of the bill and the peak that sets it is a short spike rather than your normal operating level. A flat, heavily utilised building has little to shave.
Can switching electricity suppliers lower my demand charge?
No. In Ohio you shop generation. The demand charge sits in the regulated delivery half of the bill and is set by your utility's filed tariff.
Does my load factor tell me whether peak shaving will work?
It gives you the first cut. A low load factor means your average draw sits well below your peak, which is the condition under which shifting or absorbing a peak can help. It does not tell you when the peak happened or whether it recurs, and that question needs the interval record rather than the bill.