Peak-to-Average Ratio

The inverse-style companion to load factor (PAR ≈ 100 ÷ load factor % when definitions match). Higher PAR means spikier demand.

PAR = peak demand ÷ average demand (dimensionless).

Tip: Keep “Peak Load” and “Average Load” on the same basis (period, units, and population) before calculating Peak-to-Average Ratio.

Cluster: Energy hub · Professional efficiency · Manufacturing hub · Percentage guide

Peak-to-average ratio (PAR) shows how peaked demand is relative to the average.

Enter peak load and average load in the same unit.

Peak demand
Average demand

Peak-to-Average Ratio

Understanding Peak-to-Average Ratio

How we calculate. PAR = peak demand ÷ average demand (dimensionless). The form uses the same arithmetic as the worked examples on this page. See our methodology and accuracy policy.

Real-world scenario: A typical Peak-to-Average Ratio case uses peak load 10 and average load 6.5. Enter the same figures below to reproduce the worked path.

What is Peak-to-Average Ratio?

The inverse-style companion to load factor (PAR ≈ 100 ÷ load factor % when definitions match). Higher PAR means spikier demand.

  • Same UOM for peak and average
  • Result is a ratio, not a percent
  • Pairs with load factor

The Formula

Peak-to-Average Ratio
PAR = Peak load ÷ Average load

Worked Example

Scenario: Peak 10 MW; average 6.5 MW.
Step 1: 10 ÷ 6.5 ≈ 1.54
Answer: Peak-to-average ratio is about 1.54×.

Common Use Cases

  • Tariff analysis: peakiness
  • Storage sizing: peak shaving need
  • Demand response: spike magnitude

Pro Tips

  • Use coincident peaks carefully
  • State interval length
  • Compare to load factor

Limitations: Peak-to-Average Ratio results are educational energy and utilities planning aids—not engineering, grid-operations, or investment advice. Confirm definitions with your ISO/RTO, plant, and regulatory reporting standards.

FAQ

Relation to load factor?

When average and peak match both tools, PAR ≈ 1 ÷ (load factor as a decimal).

What if average load is 0?

PAR is undefined—enter a positive average load.

Authoritative References

For power system and plant performance concepts, consult:

  • U.S. EIA — energy statistics and explainers
  • NERC — reliability standards context
  • IEA — international energy analysis