Choosing LED bulb

Choosing the Right LED Bulb

Key Factors to Consider

When selecting an LED light bulb, there are several important factors to keep in mind:

• Base
• Voltage
• Efficiency
• Colour Temperature
• Colour Rendering Index (CRI)
• Heat Output
• Lifespan

In this guide, we’ll explore each of these considerations in detail to help you make an informed decision.

Base

The base, also known as the cap, is the part of the bulb that connects to the light fitting. It provides electrical contact and secures the bulb in place. LED light bulb bases are classified by type and diameter, typically measured in millimetres. For instance, an E27 base refers to a 27mm Edison screw thread. Below are some common types:

• B22: Classic large bayonet cap (BC) with 2 pins.
• B15: Small bayonet cap (SBC) with 2 pins.
• E27: Large Edison screw thread, widely used in domestic lighting.
• E14: Small Edison screw thread, often found in desk lamps and small chandeliers.
• GU10: Plug reflector base for spotlights and downlights.
• MR16: Narrow plug base, commonly used in ceiling fixtures and furniture lighting.
• MR11: Smaller version of MR16, used in decorative lighting.
• G4: Narrow plug base for decorative applications.
• G9: Plug base commonly used in furniture lighting and decorative fixtures.

Voltage

After determining the base type, you need to select the correct voltage for your bulb. Most LED bulbs operate on 240V, except for types like G4, GU4, and AR111, which require 12V. Low-voltage lighting systems use step-down transformers to convert 240V to 12V, offering enhanced safety during installation and maintenance.

Always match the voltage to your fixture to avoid damage. For example:

• Plugging a 240V bulb into a 12V fixture will not work.
• Plugging a 12V bulb into a 240V fixture can cause the diodes to explode, permanently damaging the bulb.

If in doubt, consult a qualified electrician.

Efficiency

LED efficiency is measured in lumens per watt (lm/W), indicating the amount of light produced per watt of energy consumed. Modern LEDs are highly efficient, typically offering 80–120 lm/W, compared to earlier models that ranged from 20–60 lm/W.

LEDs emit directional light, focusing brightness where it’s needed, unlike traditional bulbs that radiate light in all directions. This directional nature maximises efficiency and reduces energy waste.

Colour Temperature

LEDs are available in a wide range of colour temperatures, from warm white (2700K–3000K) to daylight (6000K+). While early LEDs often produced a "cold" bluish light, advancements in technology now allow for a variety of warmer tones. For general home use, a colour temperature of around 3000K is ideal.

Some manufacturers use terms like "natural white" or "office white," which may not correspond to standardised colour temperatures. Always check the Kelvin (K) value for accurate comparison.

Colour Rendering Index (CRI)

CRI measures how accurately a light source reveals colours compared to natural light. LEDs typically have a CRI between 65–80, while incandescent bulbs score above 95. A higher CRI ensures natural colour representation, which is essential in workspaces or areas where colour accuracy is important.

Heat Output

LEDs generate significantly less heat than traditional bulbs, making them safer and more energy-efficient. While compact LEDs like spotlights may feel warm, larger bulbs remain cool to the touch during operation. Many LEDs feature heat sinks to maintain optimal operating temperatures and extend their lifespan.

Lifespan

One of the biggest advantages of LEDs is their long operational life, often lasting up to 100,000 hours. This equates to approximately 11 years of continuous use or 22 years at 50% operation. Unlike traditional bulbs that burn out, LEDs gradually dim over time, maintaining functionality for years.

Additionally, LEDs are free of toxic materials like mercury, making them eco-friendly and 100% recyclable. For example, a 13W LED bulb emits 68% less CO2 compared to a 40W incandescent bulb, helping to reduce your carbon footprint significantly.

Eco-Friendly Benefits

LEDs are a sustainable choice for lighting, offering several environmental benefits:

• Free from toxic chemicals like mercury.
• 100% recyclable, reducing waste.
• Lower energy consumption reduces greenhouse gas emissions.
• Long lifespan reduces material use and manufacturing demands.

Switching to LED lighting is a simple step towards a greener future, saving energy, resources, and costs over time.