The right fixed vs. variable electric rate structure depends entirely on your load profile, your load factor, and how much budget volatility your operation can absorb — there is no universally better option. A three-shift manufacturer running a flat, high-consumption load profile will almost always find more value in structures with a heavier fixed component. A seasonal operation with strong load flexibility can benefit from more variable exposure, provided the team is disciplined about managing both kilowatt demand and kilowatt-hour consumption.

If you open your electric bill and see a confusing mix of demand charges, energy charges, fuel riders, customer charges, and line items you can barely parse, this post is for you. You're probably spending more time thinking about electricity than any normal person would want to — because utilities and vendors keep adding complexity and costs without ever sitting down to explain how the structure actually works. By the end, you'll know what fixed and variable really mean on a commercial bill, when each type of structure works in your favor, and how to run your own data to find the rate that fits your facility instead of guessing.

Watch the full podcast episode here.

What Fixed and Variable Charges Actually Are

Every commercial electric bill — regardless of utility, regardless of state — is built from three broad components.

Energy charges cover the kilowatt-hours (kWh) you consume. This is how many units of electricity flowed through the meter during the billing period.

Demand charges are based on the highest rate at which you drew power over a short window — typically a rolling 15 or 30 minutes — measured in kilowatts (kW). You're not billed for how long you held that level. You're billed for the peak itself.

Fixed charges are monthly line items that appear whether you consumed a lot or a little. Customer charges, basic service fees, certain infrastructure minimums — these exist to cover the poles, wires, transformers, meters, and billing systems the utility maintains to keep the grid available for you and everyone else on it.

Here is the critical distinction. Fixed charges do not change with your consumption volume within a billing period. Variable charges scale directly with your use — more kilowatt-hours consumed means more cost, fewer kilowatt-hours means less. Your per-kWh energy charge, fuel riders, and fuel adjustment clauses all fall into the variable bucket.

On paper, that's a clean line. In practice, it gets messier — and that mess is where most operators get tripped up.

Why the Fixed vs. Variable Electric Rate Question Gets Complicated in Real Life

The complexity starts when you look at the two broad categories of commercial rates: demand-based rates and power-only rates.

Demand-based rates are the standard tariff structure for most commercial and industrial accounts. You pay a separate demand charge in dollars per kilowatt and an energy charge in dollars per kilowatt-hour. Your effective cost per kWh — what you're actually paying for each unit of electricity — isn't just the listed energy charge. It's your demand charges, fixed charges, riders, and energy charges blended across your total kilowatt-hours consumed. That blended number is your real cost.

Power-only rates — sometimes called general service rates — are built around a flat rate per kilowatt-hour with little or no separate demand component. You pay primarily for units consumed. These are more common for smaller or highly variable operations that don't justify full demand-based treatment. From a fixed vs. variable standpoint, a power-only rate behaves more like a simple variable structure: you pay a known price per kWh, use more and pay more, use less and pay less.

The complication enters through mechanisms like time-of-use demand, non-coincident demand, system peak demand, and ratchets. TEG has full posts on demand charges, time-of-use rates, and demand ratchets — if you want the deep dive on any of those, they're in the Energy Answers archive.

For the purpose of fixed vs. variable thinking, ratchets deserve special attention. A ratchet takes a percentage of your past peak demand and holds that as the floor for future billing demand. If a single bad day — a malfunction, a test run, an unusual production spike — drives your peak higher than your normal operation justifies, a ratchet locks in elevated billing demand for the next 11 months. That demand charge started as a variable cost. After the ratchet kicks in, it behaves like a fixed one. You're paying for capacity you never used again, because you used it once.

This is one of the main reasons operators feel like their bills don't respond to their conservation efforts — they're still paying for a peak that happened months ago.

When Fixed Charges Work in Your Favor

Fixed charges benefit operations with high, stable consumption and limited flexibility to shift timing. If your facility runs three shifts with a relatively flat load profile, paying a known, predictable cost for grid access gives you budget stability. You know you're going to use that infrastructure hard all year. Paying a fixed price for that access is often well worth it.

Fixed-heavy structures also provide some insulation from commodity price swings. When more of your bill is tied to steel in the ground — poles, wires, infrastructure — rather than fuel in the generation system, volatile fuel markets show up as a smaller percentage of your total cost. Not because markets stopped moving, but because more of your payment is decoupled from them.

When Variable Charges Work in Your Favor — and When They Don't

Variable structures clearly help when consumption is low, intermittent, or highly manageable. If your operation is seasonal, if you have significant on-site generation, or if you're genuinely capable of shifting load away from high-cost windows, paying primarily for what you actually use is the fair arrangement. Variable structures also reward efficiency directly: every kilowatt-hour you eliminate is immediate cost avoidance, and every shift of load away from expensive windows can drop your bill.

They also give you direct access to low commodity prices when market conditions are favorable — and in deregulated or partially deregulated markets, that exposure cuts both ways.

The problem with variable structures is exactly that two-way exposure. If your operation runs high, inflexible loads — processes that demand a lot of power on a fixed schedule — and you can't easily move consumption around, then every kilowatt-hour is exposed to market conditions. Your budget bounces with weather, fuel markets, and grid conditions. That's manageable if you can pass those swings through in your own pricing. It's a serious risk if you're running on tight margins with long-term pricing commitments.

The answer to "which is better" is never fixed or variable in the abstract. It's: what does your data say?

Load Factor: The Metric That Connects Fixed vs. Variable Electric Rates to Your Operation

Load factor is the master metric for this decision. It's the relationship between how much electricity you could have used based on your peak demand and how much you actually used.

Here's how to calculate it directly from your bill:

1. Find your billing demand in kilowatts. Say it's 1,000 kW.
2. Find the number of days in the billing period — 28, 30, 32, whatever it is.
3. Multiply billing demand × days × 24 hours. That gives you the total potential kilowatt-hours you could have used if you'd run at peak demand every hour of the billing period.
4. Find your actual metered kilowatt-hours for the period.
5. Divide actual kWh by potential kWh, then multiply by 100. That percentage is your load factor.

A low load factor means you have very high peaks relative to your average usage — you're asking the utility to hold a lot of capacity in reserve for you that you barely use. A high load factor means you're using the capacity you're drawing on more consistently.

On a demand-based rate, improving load factor either reduces your peak for the same kilowatt-hours, or increases your throughput for the same peak. Either way, you're spreading fixed and demand-based costs across more useful output. That's why load factor is the master metric — it's how you evaluate whether a rate structure with a heavy demand component is working for you or against you.

Instead of asking "is fixed better than variable," ask: what is my load factor, and how does it behave under each rate structure I qualify for?

What You Can Do This Week

1. Pull at least 12 months of bills. For each month, capture total bill, total kWh, billed kW, basic fixed charges, energy charges, demand charges, and any fuel riders or adjustment clauses.
2. Calculate your load factor for each month using the steps above. Look at the pattern over the full year — is it consistent, seasonal, or erratic?
3. Identify your fixed vs. variable split. What percentage of each month's bill is fixed charges and demand charges combined, versus purely variable per-kWh items?
4. Read your tariff options. Does your utility offer a general service rate with no demand component, a high-load-factor rate, time-of-use variants, or interruptible options? Know what you actually qualify for — not just what you're currently on.
5. Check for a ratchet clause. If your current rate includes a demand ratchet, understand how it's calculated and whether you're currently paying for a past event that no longer reflects how you operate.
6. Model last year's data against each candidate rate. If you'd been on Rate A versus Rate B, what would you have paid? How variable would those bills have been month to month?
7. Layer in your risk tolerance. Is the priority squeezing every cent out of the effective rate, or maintaining a bill that moves in a narrower band so finance can budget with confidence? Both are legitimate answers. Know which one your operation actually requires.

The Bottom Line on Fixed vs. Variable Electric Rates

Fixed and variable charge structures are not for you or against you by default. They're tools. Where you win is in understanding your utility billing — including these fixed vs. variable dynamics — better than your competitors and better than most vendors who walk through your door.

C&I operators compete with residential customers and large industrial accounts for favorable cost treatment in the rate structure environment. Residential customers have consumer advocates. Large industrial customers have regulatory staff and tariff riders negotiated specifically for their operations. The mid-market C&I account that doesn't understand its own bill is, by default, in the disadvantaged group.

When you understand your fixed and variable dynamics, your load factor, and your actual tariff options, you create real leverage. You can evaluate vendor pitches against your specific rate rather than a generic promise. You can negotiate with specifics. You can avoid being stuck on an outdated rate simply because it's what the utility put you on when you first called and said "plug us in."

The right structure is the one that, when you run your actual data through it, gives you an effective all-in cost and budget pattern your operation can live with. You find that answer through your numbers — not through generic fixed vs. variable arguments from someone with something to sell.

Frequently Asked Questions: Fixed vs. Variable Electric Rates

Q: What is the difference between fixed and variable charges on a commercial electric bill? A: Fixed charges stay the same within a billing period regardless of how much electricity you consume — they cover infrastructure like poles, wires, meters, and basic grid access. Variable charges scale directly with consumption: more kilowatt-hours used means more cost, and less usage means less cost. Most commercial bills contain both, weighted differently depending on which rate structure you're on.

Q: What is load factor and how do I calculate it from my bill? A: Load factor is the ratio of your actual kilowatt-hour consumption to the total kilowatt-hours you could have consumed if you'd run at your peak demand every hour of the billing period. To calculate it: multiply your billing demand (kW) by the number of days in the billing period by 24, divide your actual metered kWh by that number, and multiply by 100. A higher load factor means you're using your peak capacity more consistently — which typically works in your favor on demand-based rates.

Q: When does a demand-based rate make more sense than a power-only rate for a commercial facility? A: Demand-based rates generally favor facilities with high, stable consumption — operations running multiple shifts with relatively flat load profiles. If your load factor is strong and your peaks are consistent rather than spiky, the higher demand component is offset by lower effective per-kWh costs. Power-only rates favor intermittent or highly variable operations where most of the value comes from paying only for what you actually consume.

Q: What is a demand ratchet and why does it effectively turn variable demand costs into fixed charges? A: A demand ratchet is a billing clause that sets a floor on your billed demand — typically a percentage of your highest peak over the past 11 or 12 months. Even if your current demand is much lower, you continue to pay for that historical peak until the ratchet window resets. This means a single high-demand event — a malfunction, an unusual production run, a test — can lock in elevated billing demand for nearly a year, turning what should be a variable cost into something that behaves like a fixed obligation.

Q: How do I decide which electric rate structure is right for my operation? A: Run your actual data. Pull at least 12 months of bills, calculate your load factor for each month, identify your fixed vs. variable cost split, and model what you would have paid under each rate structure your utility offers. The right structure is the one that produces the best combination of effective all-in cost per kilowatt-hour and budget stability for your specific load profile — not the one a vendor or utility rep recommends without running your numbers.

Q: What questions should I ask before switching to a different utility rate structure? A: Ask: What percentage of our bill over the last 12 months has been fixed and demand charges versus variable per-kWh items? What is our average load factor, and how would it behave under the alternative rates we qualify for? Do we have a demand ratchet on our current rate, and are we still paying for a past event that doesn't reflect how we operate today? If we modeled last year's data on a power-only rate versus a demand-based rate, which would have given us a better combination of effective cost and budget stability?

If you're actively evaluating rate structures, facing a tariff change, or being pitched projects that depend on fixed vs. variable savings — and most of them do — the TEG Energy Decision Blueprint was built for exactly this decision. It walks through your actual data: 12 months of bills, interval data where available, your load profile and shift constraints. The output is a board-ready summary of which structure fits your operation, under what conditions, and where the real upside and downside are. For qualified Indiana C&I accounts, it's free.

Visit TacticalEnergyGroup.com to request the TEG Energy Decision Blueprint.

You can also watch this episode of Energy Answers by Tactical Energy Group on YouTube for the full audio walkthrough.