How do you calculate air separator energy cost per ton?

Multiply the connected fan load (kW) by runtime (hr) by your electricity rate ($/kWh) to get total cost, then divide by tons processed. At 22 kW for 8 hr at $0.12/kWh over 120 tons that is $21.12 total, or about $0.176 per ton.

What is a good energy cost per ton for an air classifier?

Well-tuned MRF air separation typically lands in the $0.10 to $0.30 per ton range. The $0.176/ton in our example is healthy; if you are above $0.40/ton you are likely oversized, running below design throughput, or both.

Why is my air separator using so much power?

The most common causes are a fan running at full speed while the line is starved of material, plugged or worn cyclone seals forcing the fan to work harder, and oversized motors specified for peak rather than typical flow. The kWh figure here (176 kWh) helps you spot the gap.

Connected load vs running load — which should I enter?

Enter the actual running fan load if you have it from a power meter. The motor nameplate (connected load) overstates real draw because motors rarely run at 100 percent. If you only have the nameplate, expect this result to be a conservative high estimate.

Does a VFD change the calculation?

Yes. A variable frequency drive cuts fan speed when flow drops, and fan power falls with roughly the cube of speed, so a 20 percent speed reduction can cut energy nearly in half. This calculator assumes fixed-speed operation, so treat its output as the upper bound.

How do I lower air separator cost per ton?

Run the separator only when material is on the belt, fit a VFD tied to feed rate, keep cyclone and ducting seals tight, and right-size the fan to typical throughput rather than peak surge. Pushing more tons through the same fan also drops the per-ton number directly.

Municipal Waste Sorting Equipment calculator

Air Separator Energy Cost Calculator

Air separators (air classifiers and air knives) are among the biggest single electrical loads in a material recovery facility, because the centrifugal fans that lift the light fraction off a fast-moving belt run continuously through the shift. This calculator converts that fan load into a real cost-per-ton number that plant managers and MRF operators can put against tip-fee revenue. Knowing the energy cost per ton tells you whether your separator is sized correctly for the throughput it is actually seeing, and where to look when your power bill jumps. It is the number most operators wish they had before they signed the utility contract.

What this calculator does

Estimate the electricity cost of running an air knife, air drum, or windshifter and convert it into a defensible cost per ton.
Use it when comparing fan settings, sizing a windshifter for a fiber line, or pricing air separation energy into a per-ton processing cost.
It computes the total electricity cost of running an air separator over a period and divides it by tonnage to give a cost per ton.

Formula used

Total air separator energy cost = connected fan load x runtime x blended electricity rate
Air separator energy cost per ton = total air separator energy cost / tons processed during runtime

Inputs explained

Air separator connected fan load:
Air separator runtime per period:
Blended electricity rate:
Tons processed during runtime:

How to use the result

Use it when benchmarking line energy against tip-fee revenue, sizing fan motors for a new sort line, or investigating an unexpected power bill spike.
It models the fan at its full connected load for the whole runtime; if your separator runs on a VFD that throttles down during low flow, actual kWh will be lower than the nameplate figure shown.

Current U.S. benchmarks

As of Apr 2026, industrial electricity averages 8.7 cents per kWh across the U.S. (EIA), up 5.5% from a year earlier. State averages range widely, so plants should confirm against their own tariff.
Steel mill PPI stands at 348.53 (BLS, May 2026), up 6.7% from a year earlier. New factory orders are up 2.3% year over year (Census).

Common questions

How do you calculate air separator energy cost per ton? Multiply the connected fan load (kW) by runtime (hr) by your electricity rate ($/kWh) to get total cost, then divide by tons processed. At 22 kW for 8 hr at $0.12/kWh over 120 tons that is $21.12 total, or about $0.176 per ton.
What is a good energy cost per ton for an air classifier? Well-tuned MRF air separation typically lands in the $0.10 to $0.30 per ton range. The $0.176/ton in our example is healthy; if you are above $0.40/ton you are likely oversized, running below design throughput, or both.
Why is my air separator using so much power? The most common causes are a fan running at full speed while the line is starved of material, plugged or worn cyclone seals forcing the fan to work harder, and oversized motors specified for peak rather than typical flow. The kWh figure here (176 kWh) helps you spot the gap.
Connected load vs running load — which should I enter? Enter the actual running fan load if you have it from a power meter. The motor nameplate (connected load) overstates real draw because motors rarely run at 100 percent. If you only have the nameplate, expect this result to be a conservative high estimate.
Does a VFD change the calculation? Yes. A variable frequency drive cuts fan speed when flow drops, and fan power falls with roughly the cube of speed, so a 20 percent speed reduction can cut energy nearly in half. This calculator assumes fixed-speed operation, so treat its output as the upper bound.

Last reviewed 2026-05-12.