How Much Electricity Does LED Grow Light Use

led grow lights

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LED grow lights have been favorite equipment by global plant growers in these years. It is due to the advantages that LED Grow Light brings

But, many are curious, how much electricity does LED grow lights use? Is it true that it can save us a lot of electricity for daily uses? 

The answer is yes. Though LED grow light incurs more electricity than outdoor grows, it is much lesser than other types of grow lights. For instance, high-intensity discharge (HID) lights and compact fluorescent lamps (CFL). In fact, LED grow lights are high in energy efficiency that brings the highest performance with less heat. It saves you more electricity costs and brings more value over money.

You can expect less than hundreds of dollars monthly if you run a small garden with grow lights. Yet, the myth that it costs you almost zero is definitely not right. The precondition to benefit from LED grow lights is knowing how to use your LED Grow Lights.

It is crucial to understand how to calculate the electricity costs used by your LED grow lights. This method will help you plan ahead of the operations costs of your indoor grow room. 

In this post, we’ll share the step-by-step calculation to help you get the energy consumption by your LED grow lights. Let’s dive right in! 

led grow lights

LED Watts vs True Watts of a LED Grow Light

Most manufacturers will label their LED grow lights with only “LED Watts,” or theoretical wattage. These numbers are often more impressive and higher than true watts, hence great for advertisement. 

Yet, it is not right to run a LED grow light according to this manufacturer’s LED wattage. There is a reason we call it theoretical wattage – we do not run LEDs at this full-rated wattage in real-world applications. Otherwise, it will produce excessive heat and lead to LED burnout and color shift. 

You should study this article about the Top 11 Things to Consider When Purchasing LED Grow Lights to ensure that you buy the right LED grow light for your indoor plantation use. 

To explain further, two grow lights with 1,000 Watts could produce different true watts. One might generate 300 true watts, and another produces 700 true watts. So, the LED watts are almost useless when comparing light outputs.

You should always check for the true wattage of a LED grow light and not the manufacturer’s wattage. LED watts are the most precise measurements to plan and compare for your grow room usage. 

Ensure that the power circuit of your indoor plant grow room can stand the power draw. You are recommended to use only 75% of your fuse’s rated ability for safety purposes. For instance, do not exceed 15 amps usage for a 20-amp circuit. 

Besides the circuit usage, there are many other parts to take note of while using LED grow lights. It is crucial to have a thorough understanding to prevent spoiling the LED grow lights. You can visit this article to learn more about 9 mistakes to avoid when using LED grow lights.

plant growing inside light bulb

How to Calculate the Electricity that my LED Grow Light Use?

You should first collect the required information to make this simple calculation. Let’s carry out the electricity cost calculation step by step:

Step 1: Calculate the True Watts

Firstly, it’s the true wattage of your LED grow light that we mentioned above. Not all LED grow light manufacturers display the true watts of their product. 

Let’s take an example from Darkless LED products – the High Efficiency LED Grow Light 850W/640W. This product has the actual power listed on the website, which is 850W ± 5%. We’ll need to convert to kWh, the unit that the electricity companies use. 

Just divide the true watts by 1,000, and you’ll get a 0.85 kWh power draw. 

led grow light

Step 2: Calculate the Time Length Used

Next, you’ll need to know the daily number of hours you use the LED grow lights. 

For instance, marijuana needs 18hours of lights daily in its vegging stage. Whereas 12 hours of lights daily in its flowering stage. You can visit this link to learn the Things You Need to Know About LED Grow Cannabis Lights.

We can take the vegging stage as an example, combined with the product listed above. It means that this indoor plant will need 18 hours of 0.85kWh lights daily. 

You can use the formulae below to calculate the electricity consumption by your LED grow light:

     Daily Power Consumption (kWh) = Power Consumption (kWh) x Number of Hours (h)

By multiplying 0.85kWh with 18 hours, we know that you’ll need 15.3kWh power consumption daily for your marijuana plant. 

   I.e., 0.85kWh x 18h = 15.3kWh

Make sure you learn about How Close Do LED Grow Lights Need To Be before using them for your plants for a long time. Otherwise, the LED grow lights can burn your plants without proper use!

led vs cfl grow lights (1)

Step 3: Calculate the Electricity Cost

Then, you should determine the electricity rate to finally know the electricity cost. This piece of information is available on your power bill. Or, you can visit this link to find out more about the average retail price of your power consumption.

Based on a study, the average electricity price in the US will be 10.66 cents per kWh in 2020. It means $0.1066 per kWh. To calculate the daily electricity cost to run your LED grow light, you’ll need the formula below:

   Electricity Cost ($) = Power Consumption (kWh) x Electricity Rate ($)

We can substitute the amount into the calculation above to get daily electricity cost:

   I.e., 15.3kWh x $0.1066 = $1.63098 daily

You can further the calculation to calculate monthly electricity cost. Simply multiply the daily electricity cost by 30:

   I.e., $1.63098 x 30 = $48.9294 monthly

The Complete Formula to Calculate Electricity Cost

  1. Determine the actual wattage (kWh)
  2. Determine the daily number of hours used (h)
  3. Determine the electricity rate
  4. Multiply items 1 & 2 to get daily electricity consumption

(e.g., 0.85kWh x 18h = 15.3kWh)

  1. Multiply daily electricity consumption with electricity rate to get daily electricity cost
    (e.g., 15.3kWh x 0.1066 = $1.63098)
  2. Multiply daily electricity cost by 30 to get monthly electricity cost

(e.g., $1.63098 x 30 = $48.9294)

You can also use this electricity calculator to make a brief calculation. 

grow lights indoor plants seedlings tomato 218937511

Are LED Grow Lights Cheaper to Operate?

Actually, the operation costs for a 1000W fluorescent grow light, and a 1000W LED grow light is almost similar! So, is the statement “LED grow lights cut more electricity cost” incorrect?

Let’s take a deeper insight so you can understand further. 

The fact is true that the electricity cost to run different lights of the same watts is identical. But, we should also look at the wattage, which tells about the electricity costs. 

You can compare the watts and lumens to understand the light efficiency of different grow lights.

Watts defines the energy consumption of an appliance over a specific period. At the same time, Lumens tell about the amount of light produced by a device over a particular period. 

Electricity Costs: LED Grow Light vs Fluorescent Grow Light

A 10000W LED grow light can grow more indoor plants using the same power consumption as a 1000W fluorescent grow light. It means that LED grow lights are more energy-efficient as they generate more high-intensity lights. These lights will also allow botanists to grow a bigger area. 

For instance, you can use a 300w or 400w LED grow light to replace a 600w fluorescent grow light. They produce the same amount of light but LED grow light saves you half the electricity cost.

Common examples of fluorescent grow light are the Compact Fluorescent Lamp (CFL), Cold Cathode Fluorescent Light (CCFL), and Tube-style Fluorescent Lights.

cfl grow light

Electricity Costs: LED Grow Light vs Incandescent Grow Light

What about the difference between incandescent grow lights with LED grow lights? Generally, standard incandescent light with a 60 watts light bulb will generate about 730 to 800 lumens.

In contrast, it only requires 7 to 9 watts from a LED bulb to produce the same 730 to 900 lumens.

It shows that an LED bulb has the same amount of light at 85 – 88% efficiency compared to an incandescent light bulb. In other words, your LED grow light only needs 10% of the energy of an incandescent light bulb for the same light output. 

Electricity Costs: LED Grow Light vs High-Intensity Discharge Light 

High-intensity discharge lights produce more heat as compared to LED grow lights. While using it for summer plantations, you’ll need to consider lowering the plant’s temperature due to the high heat emission of HID lights. It will further increase the cost of your indoor plantation.

You can use LED grow lights with lower wattage to produce the same output as HID lights. For instance, A 600 watts LED grow light can replace a 1,000 watts HID grow light for vegetative growing. Usually, a plant needs 18 hours of light during the vegging stage.

hid grow light

Let’s see how much electricity a LED grow light can save you: 

   (1.0 – 0.6 kWh) x 18hours x 30 days = 216 kWh

This LED grow light saves you about 200 kWh to operate a grow room for 30 days, compared to HID grow lights. Imagine how much electricity it saves you when using it for a year or more!

The types of HID lights include Metal Haliade (MH), Ceramic Metal Haliade (CMH), High-Pressure Sodium (HPS), Conversion Bulbs, Switchable Ballasts, and Combination of MH and HPS (Dual Arc).

The Verdict

So, you can choose a lower-wattage LED grow light to grow a specific amount of indoor plants instead of a higher-wattage fluorescent grow light or incandescent grow light. The LED grow lights help you cover a bigger area while saving at least 75% less energy.

You can visit this link to learn How LED Grow Lights Work making them energy-efficient. 

Final Thoughts

LED grow light has changed the way of indoor plant cultivation all over the world. Though more expensive, LED grow lights are proven more convenient and energy-saving. 

We’ve demonstrated how much electricity costs a LED grow light can save you from, compared to other lights. I believe the numbers can tell you how well LED grow lights can perfectly replace incandescent grow lights and fluorescent grow lights. If you are new to this device, you should learn how to choose an LED grow light and how to use LED grow lights for indoor plants.

Darkless LED is your reliable manufacturer supplying LED grow lights to companies worldwide. Our professional team will guarantee the best workmanship in producing LED lights for your need. Talk to us today to get your customized LED grow lights!

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