Leni Lighting Energy Numeric Indicator

Overview

Engineering reference data for Leni Lighting Energy Numeric Indicator in electrical engineering.

Key Formulas

Ohm's Law

$V = IR$

Voltage = Current × Resistance.

Power

$P = VI = I^2R = V^2/R$

Electrical power.

Energy

$E = Pt$

Energy = Power × Time.

Variables

LENI Formula

The core formula for calculating the Lighting Energy Numeric Indicator (LENI) as per EN 15193 is expressed as:

$$LENI = \frac{\sum\left(P_n \cdot f_c\right) \cdot \left[\left(t_d \cdot f_o \cdot f_d\right) + \left(t_n \cdot f_o\right)\right]}{A}$$

This indicator, measured in kWh per square metre per year (kWh/(m²·year)), represents the actual annual energy consumption of a lighting system normalized by the area it serves. The formula accounts for installed power, control factors that reduce energy use, and the operational hours during both day and night.

References

• Original Source