When you start thinking about reducing your energy usage and shaving off a few dollars of your electricity bill, you usually worry about things like the dishwasher, washing machine, or heating. One item you probably don’t think twice about is your light bulbs. Why? They are small, so they can’t consume that much electricity, even if you leave them on all day right? Well, let’s explore if that’s the case.
How Much Energy Does a Light Bulb Use?
Do light bulbs use a lot of electricity? While individual bulbs consume small amounts of electricity (around 40 watts), the tricky part is that you probably have a lot of them in the house, so the costs quickly add up. Just think about every room of your house and count the number of bulbs you have – it can easily be up to twenty or thirty!
Each light bulb you buy will have its wattage displayed on the box so you can quickly tell how much energy will it consume. For example, if you keep a 60-watt incandescent bulb on for an hour, it will burn, well 60 watts. However, that does not mean that it will give you the same amount of light, as another 60-watt bulb.
Different Bulbs Use Different Amounts of Energy
There are generally three types of light bulbs:
Incandescent bulbs – This old-fashioned, 100-years old technology emits light by heating the filament inside the bulb. Because of the low efficiency, these bulbs are being phased out at speed. In 2010, they were installed in 68% of U.S. homes but by 2016, this number dropped to 6%.
Compact fluorescent light bulbs (or CFLs) – This bulb is largely perceived as a replacement for incandescent or halogen lamps and is mainly available in two forms – screw-in and plug-in. They are four times moreefficientand last up to 10 times longer than incandescents (a 22 wattsCFLwill give you as much light as a 100-wattincandescent).
Light-emitting diodes (LEDs) – Crown jewels among the light bulbs. This technology is relatively new on the market, incredibly 90% more efficient, and lasts 25 times longer than incandescent bulbs; and the bulbs are so thin that they can be designed in any way imaginable. Despite its widely-acknowledged benefits, some people worry that LEDs might have adverse health effects, mainly due to emitting blue lighting.
To make a comparison between these types of bulbs easier, we will use lumens. Lumens measure how much light you are getting from a bulb. More lumens means it’s a brighter light; fewer lumens means it’s a dimmer light.
The 60 watts incandescent light bulb we mentioned before will produce approximately 800 lumens. However, a LED bulb will only need approximately 11 watts to produce the same amount of lighting, therefore saving your electricity.
Use this handy table to guide you next time you go shopping for light bulbs!
| Incandescent Bulb Wattage | Equivalent Halogen Bulb Wattage | Equivalent CFL Bulb Wattage | Equivalent LED Bulb Wattage |
|---|---|---|---|
| 40 W(~460lm) | 28 W | 7 W | 6 W |
| 60 W(~830lm) | 45 W | 13 W | 11 W |
| 75 W(~1100lm) | 56 W | 18 W | 15 W |
| 100 W(~1800lm) | 80 W | 28 W | 24 W |
Determining Wattage and Usage
Coming back to our initial question – will lights burn a lot of electricity if we leave them on? Let’s work with the assumption that you have thirty 60 watts incandescent lightbulbs. If you live in Texas and you haven’t yet switched energy suppliers, you are probably paying the standard energy tariff of 12 cents per kilowatt-hour. Leaving the lights on the whole day will therefore cost you:
30 bulbs x 0.06 (60 watts / 1000) kilowatts x 24 hours x 12 cents = $5.2 a day.
Not the end of the world, but these costs can add up relatively quickly.
Energy Inefficiency Due to Heat Loss
Another downside of incandescent bulbs is the heat loss – nearly 90% of energy is wasted as produced heat and only about 5% is turned into visible light. That puts this type of bulb at a high risk of overheating and becoming a fire hazard. You probably know it – when you are changing an incandescent bulb, you always have to wait a few minutes because you would burn your fingers.
LEDs produce almost no heat when they are burning and are kept cool even during prolonged periods of being on. In addition, LEDs operate on low-voltage electrical systems, as well as in cold temperatures, don’t contain any mercury, or emit UV or infrared radiation.
How Can You Save Money on Light Bulbs?
Next time you are due to replace your lights, you should opt for LED bulbs instead of CFLs or incandescents. If you currently have 30 bulbs at home,you can save up to $200in a year if you upgrade all bulbs to LEDs. In addition, the averagelife expectancyof anLED lightbulb is 50000 hours. That means that if you use it for 10h a day, it should last you 14 years. You are more likely to change your house before you need tochange the light bulb.
You can also switch electricity suppliers to pay less for the energy used by your lights. If you live in Texas and you haven’t yet switched, you are probably paying around 11.85 cents per kWh. However, a quick look at offers from other providers returns several long term contracts with an average rate of approximately 5.99 cents, reducing your energy bill even lower.
FAQs
How Much Does it Cost to Leave A 60-watt Light Bulb On for 24 Hours?
Calculating the energy usage of a light bulb is relatively straightforward and will only take you a few minutes. Let’s say you have a 60-watt incandescent lightbulb and you are paying 12 cents per kWh of energy. Leaving the bulb on the whole day will therefore cost you:
0.06 (60 watts / 1000) kilowatts x 24 hours x 12 cents = approximately 20 cents in one day.
Does Leaving the Lights On Cost a Lot Of Money?
Individual light bulbs won’t use a lot of energy, but the costs can quickly add up. Just consider that anaverageU.S.householdhas 45 lightbulbs, so if you forget to turn them off before you leave on holiday, you might be coming home to a steep bill. You can reduce the energy consumed by investing in LEDs (light-emitting diodes) which are approximately 90% more efficient than incandescent lights.
Is it Ok to Leave a Light On All Night?
Leaving one light bulb on during the night will probably not make a dent in your wallet, but you shouldn’t get into the habit of leaving lights on at all times. Given that anaverageU.S.householdhas 45 bulbs, leaving them on all night can cost you approximately $2.5 (45 incandescent bulbs x 0.06 kilowatts x 7H x 12 cents). Over the course of a month, this can quickly add up.
We hope that this article gave you some food for thought for the next time you will be shopping for new lights. Although the energy cost of leaving one bulb on for the day isn’t high, these costs can quickly add up. Investing in LEDs, which are not only 90% efficient, but also last longer will pay for itself in the long run – a bonus is that the design possibilities for LED lights are endless.
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As an enthusiast with a demonstrated depth of knowledge in energy efficiency and lighting technology, I can confidently address the concepts covered in the article. My expertise in the field allows me to provide valuable insights into the energy consumption of light bulbs and the cost-saving benefits of using energy-efficient alternatives.
Firstly, the article delves into the misconception that individual light bulbs consume negligible electricity due to their small size. However, it emphasizes that the cumulative effect of multiple bulbs in a household can significantly impact electricity costs. This aligns with the basic principle of energy conservation, where small changes in individual behavior or devices can lead to substantial overall savings.
The article categorizes light bulbs into three main types: incandescent bulbs, compact fluorescent light bulbs (CFLs), and light-emitting diodes (LEDs). Drawing on my expertise, I can elaborate on each type:
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Incandescent Bulbs:
- Emit light by heating a filament, a technology that's over 100 years old.
- Phased out due to low efficiency and high energy consumption.
- Notable for heat loss, with nearly 90% of energy wasted as heat.
- Prone to overheating and considered a fire hazard.
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Compact Fluorescent Light Bulbs (CFLs):
- Positioned as replacements for incandescent or halogen lamps.
- Four times more efficient than incandescents and have a longer lifespan.
- Available in screw-in and plug-in forms.
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Light-Emitting Diodes (LEDs):
- Considered highly efficient, being 90% more energy-efficient than incandescents.
- Last up to 25 times longer than incandescent bulbs.
- Minimal heat production, operates on low-voltage systems, and environmentally friendly.
The article introduces the concept of lumens as a measure of the brightness of a bulb. It emphasizes that a lower wattage LED can produce the same amount of light as a higher wattage incandescent or CFL bulb, leading to energy savings.
Furthermore, the article discusses the financial implications of leaving lights on, calculating costs based on the wattage and duration of use. It also touches upon the environmental impact of inefficient bulbs, such as incandescents, which waste a significant amount of energy as heat.
The final section provides practical tips for saving money on light bulbs, advocating for the use of LED bulbs over other alternatives. It also suggests considering a switch to a more cost-effective energy supplier to reduce overall electricity expenses.
In summary, my expertise in energy efficiency and lighting technology allows me to offer a comprehensive understanding of the concepts covered in the article, from the characteristics of different bulb types to practical tips for reducing energy costs.
