Question 1

How is load factor calculated?

Accepted Answer

Load factor equals average kW divided by peak kW over the period. For a 24-hour day it is (sum of 24 hourly kW / 24) divided by the maximum hourly kW. A value above 0.75 is excellent, 0.50–0.75 is good, and below 0.50 is spiky.

Question 2

How do you size a battery to shave peak demand?

Accepted Answer

Set a target peak (typically 80% of the observed peak). The required BESS discharge power is peak minus that target, and the energy capacity is that power multiplied by the discharge duration. For example, a 34 kW peak shaved to 27.2 kW needs about 6.8 kW × 2 hours = 13.6 kWh of usable battery capacity.

Question 3

What demand-charge savings can I expect?

Accepted Answer

Monthly demand-charge savings equal the kW of peak shaved multiplied by the tariff rate. At $12 per kW-month, shaving 6.8 kW off a 34 kW peak saves roughly $81.60 per month, or about $980 per year, before considering battery cost and degradation.

Target peak (80%)	—
Required discharge power	—
BESS capacity (2 h)	—
Demand-charge saving	—

Load Profile Analyzer

Hourly Load Readings

Analysis Results

BESS Sizing for Peak Shaving

Why this matters