Cooling Load from Lighting Calculator

Cooling Load from Lighting Formula:

\[ Q_l = 3.4 \times W \times BF \times CLFL \]

Cooling Load from Lighting (W):

1. What is Cooling Load from Lighting?

Definition: This calculator estimates the cooling load caused by heat gain from lighting systems in a building.

Purpose: It helps HVAC professionals and engineers determine the additional cooling required to offset heat generated by lighting.

2. How Does the Calculator Work?

The calculator uses the formula:

\[ Q_l = 3.4 \times W \times BF \times CLFL \]

Where:

\( Q_l \) — Cooling load from lighting (Watts)
\( W \) — Lighting capacity (Watts)
\( BF \) — Ballast factor (typically 0.70-1.2)
\( CLFL \) — Cooling load factor for lighting

Explanation: The formula accounts for the total wattage of lights, the efficiency of the ballast, and the heat transfer characteristics.

3. Importance of Cooling Load Calculation

Details: Proper calculation ensures adequate HVAC system sizing, energy efficiency, and occupant comfort by accounting for all heat sources.

4. Using the Calculator

Tips: Enter the lighting capacity in watts, ballast factor (default 1.2), and cooling load factor (default 1.0). All values must be > 0.

5. Frequently Asked Questions (FAQ)

Q1: What is the ballast factor?
A: The ballast factor (0.70-1.2) indicates how much light a lamp will emit with a specific ballast compared to a reference ballast.

Q2: Why is there a 3.4 constant in the formula?
A: The 3.4 factor converts the lighting power input to cooling load, accounting for radiant and convective heat components.

Q3: When would I change the cooling load factor?
A: Adjust CLFL based on lighting type, space usage patterns, and heat transfer characteristics of the space.

Q4: How do I find the lighting capacity?
A: Sum the wattage of all lighting fixtures in the space or check manufacturer specifications.

Q5: Does this include all heat from lighting?
A: This calculates the immediate cooling load; some radiant heat may be absorbed and released later.