Inputs

Fixture count Enter a numeric project value at or above 1. Existing watts per fixture W Enter a numeric project value in W at or above 0.1. New watts per fixture W Enter a numeric project value in W at or above 0.1. Operating hours per day h/day Enter a numeric project value in h/day between 0 and 24. Operating days per year days/year Enter a numeric project value in days/year between 0 and 366. Additional control savings % Enter a numeric project value in % between 0 and 100. Energy tariff $/kWh Enter a numeric project value in $/kWh at or above 0.

Existing annual kWh -- kWh/year

New annual kWh -- kWh/year

Annual kWh saved -- kWh/year

Energy reduction -- %

Calculation details

Existing annual kWh: -- kWh/year
New annual kWh: -- kWh/year
Annual kWh saved: -- kWh/year
Energy reduction: -- %
Annual cost saved: -- $/year

Important notes

Use dated tariffs, measured loads, commissioned control settings, and product system watts where possible.
This estimate does not address electrical safety, lighting quality, demand charges, NCC outcomes, or Australian compliance.

Formulas

$\displaystyle E_{\mathrm{old}} = nP_{\mathrm{old}}hd/1000$
$\displaystyle E_{\mathrm{new}} = nP_{\mathrm{new}}hd(1-s_{\mathrm{control}})/1000$
$\displaystyle S = E_{\mathrm{old}} - E_{\mathrm{new}}$
Savings are estimates from user-stated load, schedule, control, and tariff assumptions.

Compare existing and new lighting annual kWh and cost savings using explicit operating and control assumptions.

Lighting Annual Energy Savings Calculator is a planning aid. Keep the target source, product data, measurement method, and project assumptions with the result. Confirm compliance, installation, certification, and safety decisions with the responsible professional.

Inputs

Results

Formulas