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Energy Cost & Payback — compare panel scenarios

Tool · 02 of 06
Step 1

Cold-room load

kW
From the Heat Load Calculator (Tool 1) — or enter your own.
System type
Drives default COP — cooler ≈ 2.5, freezer ≈ 1.6.
Step 2

Operation profile

h/day
days/year
%
Compressor doesn't run at 100%. Typical 60–80%.
—
Cold output ÷ electric input.
—
Better-insulated room ⟹ slightly higher COP (smaller compressor at the design point).
Step 3

Scenario A — current / baseline

Step 4

Scenario B — Foster upgrade

$
Cost premium of B over A (panels + extra installation).
Step 5

Tariff & finance

$/kWh
U.S. commercial average ≈ $0.13–0.16/kWh (EIA, 2026); varies by state.
%/year
%/year
For 10-year NPV.

How this calculator works

The energy cost and payback calculator converts a walk-in refrigeration load (in kW) into annual USD electricity spend, compares two panel insulation options (Panel A vs Panel B), and computes simple payback period and 10-year net-present-value of the upgrade. Annual energy consumption is calculated as: load (kW) × annual run-hours × system COP−1. COP defaults use ASHRAE Handbook — HVAC Systems and Equipment typical values for the entered temperature class. Electricity tariff defaults follow the U.S. EIA average commercial retail rate; adjust for your state and utility. Payback = (capital cost difference) ÷ (annual energy saving). NPV uses your entered discount rate and energy price escalation. Results are indicative; actual savings depend on occupancy pattern, duty cycle, and installed equipment COP.

References: ASHRAE HVAC Systems and Equipment Handbook 2020; U.S. Energy Information Administration (EIA) electricity price data; ASTM C518.