GY Lighting Guide: How to Calculate Lumens and Choose the Right High-Efficiency Bulb (EU Standard)

In Europe, energy conservation and environmental protection have become central to lighting choices.
Many people still look at the wattage when buying light bulbs, but in modern lighting systems, wattage represents power consumption, while what truly determines brightness is the lumen .

As a brand focused on high-efficiency lighting, GY · Green & You hopes to help you easily understand how to choose the right light bulbs according to EU standards, making your home brighter, more energy-efficient, and more environmentally friendly through this article.

1. What is a lumen? Why is it more important than wattage?

Lumens (lm) represent the total amount of visible light emitted by a light bulb.
Simply put, the higher the lumen count, the brighter the bulb.

Wattage (W) only indicates the amount of electrical energy consumed and does not represent brightness.
Therefore, two LED lights with the same 3W–5W rating may have completely different brightness levels.

Below is a comparison between common lighting fixtures and GY high-efficiency light bulbs:

Special note: The lighting effect of Class A directional lights needs to be multiplied by the EU coefficient of 1.176.

For directional lamps like the GY GU10 2.9W 520lm , EU regulations require that the luminous efficacy be multiplied by a directionality correction factor of 1.176 .

Effective luminous efficacy = (520 × 1.176) ÷ 2.9 ≈ 211 lm/W

 Therefore, this product achieves ≥210 lm/W , classifying it as a top-tier energy-efficient bulb in the EU's Class A category .

II. EU Standard for Household Lighting Luminance (EN 12464-1)

EU lighting standards use illuminance (Lux) to express luminance, which is the amount of light received per square meter (1 Lux = 1 lumen/㎡).

Calculation formula:

Total lumens = Room area (㎡) × Recommended illuminance (Lux)

For example,
A kitchen of 12㎡ × 400 Lux = 4800 lumens can be achieved by using multiple GY GU10 2.9W lamps.

III. EU Energy Efficiency Ratings A–G: Understanding the Labels is Key to Buying the Right Light Bulb

Since 2021, the EU has implemented a new energy efficiency labeling system.

 GY's Promise

·         All lighting fixtures comply with the new EU energy efficiency regulations.

·         Focusing on the most efficient A, B, and C grade products.

·         Made with environmentally friendly materials, it complies with CE and RoHS standards.

IV. How to choose the right lighting for yourself?

1. Look at lumens first, not wattage.

For example,
the effective luminous efficacy of the GY GU10 2.9W 520lm (Class A) exceeds 211 lm/W , far surpassing that of ordinary GU10 bulbs on the market.

2. Select the color temperature (Kelvin) according to the intended use of the space.

3. Optimized layered lighting layout

Main light + auxiliary light + ambient light
enhance illumination details and make the space more comfortable.

4. Focus on lifespan: GY lasts longer than ordinary LEDs.

This is the part that corresponds to your request

·         GY high-efficiency LED lights (Grades B and C) have a lifespan of ≥ 30,000 hours.

·         GY Class A top-efficiency lamps have a lifespan of up to 50,000 hours.

Compared to the typical 10,000–15,000 hours lifespan of ordinary LEDs:
More durable, more cost-effective, reduces replacement frequency, and is more environmentally friendly.

V. Conclusion: GY's light shines for you.

Choosing the right light bulb is easy in just three steps:

1.      Required lumens = Area × Recommended illuminance

2.      Choose the correct energy efficiency rating : Prioritize A–C.

3.      Choose the appropriate color temperature and match the number of light fixtures appropriately.

4.      GY · Green & You believes that
green lighting is not only about saving energy, but also a lifestyle.
Let every light illuminate your space and protect the future of our planet.