If you want to save energy and money on your lighting, you need to determine its efficiency. In this article, we will discuss how to tell if a light bulb is energy efficient. Additionally, we’ll provide tips for choosing the right bulb for your needs.
Light bulbs are the most common and used household appliance worldwide. Energy-efficient light bulbs consume less energy and save more money on your electricity bills. Moreover, they also help reduce greenhouse gas emissions and protect the environment. There are four main types of light bulbs that you can use for your home lighting.
Here’s a table for a quick comparison.
Wastes 90% of energy as heat
Saves 25% energy compared to Incandescent bulbs
Saves 75% energy compared to Incandescent bulbs
Saves 85% energy compared to Incandescent bulbs
Filament in a vacuum chamber
Filament in a halogen-filled chamber
Solid-State Light Emitting Diodes
Energy Label of a Light Bulb
One of the easiest ways to tell if a light bulb is energy efficient is to look at the energy label that comes with the bulb. The energy label is a standardized label that shows the key information about the energy-saving light bulb’s facts. The energy label has four main elements:
Let’s take a closer look at each and understand how they can help you choose the most energy-efficient light bulb for your home.
1. Energy Efficiency Class
The energy efficiency class is a letter from A to G that indicates how much energy the bulb uses compared to a standard incandescent bulb. This new efficiency label is in effect as of September 1st, 2021. The best bulbs belong to category A or B. The worst bulbs are those in category G.
Here’s a table showing the luminous efficacy of each class.
Energy Efficiency Class
Total Luminous Efficacy
185 to 210Lm/W
160 to 185Lm/W
135 to 160Lm/W
110 to 135Lm/W
85 to 110Lm/W
2. Energy Consumption
The energy consumption is the amount of electricity that the bulb uses in watts (W) or kilowatt-hours (kWh) per year. The lower the energy consumption, the more energy efficient the bulb is. This is one of the most important energy saving light bulb facts you need to consider when making a purchase decision.
For example, a 10 W LED bulb uses 10 kWh of electricity per year, while a 60 W incandescent bulb uses 60 kWh of electricity per year. The energy consumption also affects the running cost of the bulb, as you pay for the electricity you use.
3. Manufacturer’s Name and Model Number
The manufacturer’s name and model number are the identification of the bulb and the brand. These details can help you find more information about the bulb online or in stores. You can also compare different models and prices. The product details can also help you check the quality and the warranty of the bulb, as well as the customer reviews and ratings.
4. QR Code
A QR code is present at the base of an energy label which can be scanned to gain detailed information about the bulb.
Besides energy efficiency, there are other factors that you need to consider when choosing the right light bulb for your needs. These factors include the light output, the color temperature, and lifespan. These factors affect the quality and the mood of the lighting, as well as the appearance of the objects and colors in the room.
1. Light Output
Different types of bulbs have different light outputs per watt, which means that a lower-wattage bulb can produce the same amount of light as a higher-wattage bulb if it is more energy-efficient. To choose the right light output for your needs, you need to consider the size and the purpose of the room.
For example, a living room may need more light than a bedroom, and a reading lamp may need more light than a night light. A general rule is to multiply the area of the room in square feet by 10 to get the total light output in lumens that you need.
You can use this table to compare the light output per watt of different types of bulbs
Light Output per Watt
80 – 100Lm/W
50 – 70Lm/W
15 – 20Lm/W
10 – 15Lm/W
Also, take a look at the 7 Advantages of Smart Bulbs Over Regular LED Bulbs
2. Color Temperature
The color temperature is the color of the light that the bulb emits in kelvins (K). It affects the mood and the ambiance of the lighting, as well as the appearance of the objects and colors in the room. Choose a lower or higher color temperature based on your requirements.
- Low color temperature: Warm and yellow light for rooms where you want to relax, such as living rooms and bedrooms
- High color temperature: Cool and blue light for rooms where you want to work, such as offices and workshops.
You can use this table to compare the color temperature of different types of bulbs:
Color Temperature (K)
2200K – 6500K
2700K – 6500K
2800K – 3200K
2700K – 3000K
To choose the right shape, consider the type and the size of the fixture, as well as the purpose and the style of the lighting. Here are a few shapes and their uses.
- A standard shape works well for most fixtures, such as table lamps and ceiling lights.
- A globe shape works well for decorative fixtures, such as pendant lights and chandeliers.
- A spot shape works well for fixtures that need to create a focused beam of light, such as spotlights and accent lights.
- A flood shape is suitable if you want to create a wide beam of light, such as security lights and outdoor lights.
- A tube shape may work well for fixtures that need to provide a linear and uniform light, such as under-cabinet lights and strip lights.
The lifespan is the expected lifetime of the bulb in hours or years. The longer the lifespan, the more durable and reliable the bulb is. The lifespan also affects the replacement cost of the bulb, as you need to buy fewer bulbs over time. For example, a 10 W LED bulb can last for 25,000 hours or 25 years, while a 60 W incandescent bulb can last for only 1,000 hours or 1 year.
Light bulbs come with various bases with different sizes and shapes such as E26, E27, etc. Check your socket and purchase a bulb that matches.
Also, check out our comparison blog – CFL Vs LED: Which is More Energy Efficient?
The most common types of energy-efficient bulbs are compact fluorescent lamps (CFLs) and light-emitting diodes (LEDs). These bulbs have many advantages and disadvantages compared to incandescent bulbs, which are discussed below.
Consume 25-80% less energy.
Lasts much longer.
May be incompatible with some light fixtures and dimmers.
Reduces greenhouse gas emissions.
Light and color quality not same.
Must Read: 100 Ways to Conserve Energy at Home
With the information mentioned above, we’ve learned how to determine if a light bulb is energy-efficient. Just check the energy label that comes with the bulb, look at the energy efficiency class and consumption specifics, or scan the QR code. We have also covered the pros and cons of an energy-efficient bulb. By following these factors, you can reduce energy costs and your environmental footprint. Thank you for reading!