Indoor LED Grow Lights Explained
The LED grow light has exploded onto the market with all the top-rated grow lights for 2018 being light emitting diodes or LED as they are most commonly known. LED grow lights are favored for their extreme efficiency, cool operating temperature and long-life span.
LED lights use only 10% of the energy of an incandescent bulb.
On top of it they are able to produce as much as 300 W with a single bulb.
Like the old-fashioned incandescent bulbs LED lights can emit full brightness without having to heat up. They don’t require a ballast, nor do they burn as hot as an HID and always remain cool to the touch.
The popularity and flexibility of LED grow lights are such that within a few years they could very replace every other lighting system on the market. It is estimated that their share of the market will increase more than 12-fold over the next ten years.
Part of the reason for their high efficiency is that LED lights operate on direct current or DC energy. An LED driver is built right into the unit that will convert standard 120 AC voltage to the lower amperage DC as the product is used.
The fact that they’re DC makes them simple to use with alternative energy sources like wind or solar that already produce DC energy. Because LED grow lights are DC saves the user with alternative energy sources the expense of an AC inverter.
This makes LED great for use in more remote areas which excellent news for growers looking to stay under the radar.
History of LED
Light emitting diodes date all the way back to 1960 and after some further development and testing they began to be used in digital and electronic equipment. By the nineteen seventies many clocks on radios, stoves and microwaves were almost exclusively LED.
The use of LED took a huge step forward in the mid-nineties when the Chinese began experimenting with their use as an efficient lighting source. After further development and additional testing, they jumped into the market in a big way by 2004.
By 2007 the first fully LED grow lights were emerging onto the marketplace.
The growing popularity of LED lighting inspired the leading lighting manufacturer Phillips, to completely discontinue development of compact florescent (CFL) lighting during 2008 to fully concentrate on the future of LED.
This should tell us the direction LED is going.
Flexibility of LED
Part of the appeal of LED grow lights today is the great flexibility they afford. Most often they are designed with multiple adjustable rows, so the light can be directed exactly where its needed.
LED is also convenient because it doesn’t require a ballast to regulate voltage like a florescent light does. This gives them a huge advantage because the grower doesn’t have to constantly worry about one burning out at just the time they need.
They also don’t produce any noticeable heat and are always cool to the touch. This eliminates the headaches of burning leaves because the grow light was placed too close to the plants. This was a major factor for closet and grow tent growers who often work in more confined spots.
Additionally, needless to say, cool burning LED also completely eliminates any concerns of an accidental fire in the greenhouse or growing room.
Another nice update to LED is that they are now designed in styles with the conventional screw in end that became popular with the incandescent bulb. This makes it simple to upgrade existing lighting systems many growers still use.
LED grow light styles
The complication of LED grow lights for growers in recent years has been the great diversity of styles and options that are available. Gone are the days of stringing a row of construction light across the room and hoping they produce enough light.
LED styles are constantly evolving and at this stage the only drawback may that the one you purchase this year is already outdated by the next. The one consistency with LED grow lighting is that many have numerous rows of independently rotating lights.
There are some models the grower can adjust to five separate directions on the same unit which really provides flexibility on where the light is needed most. There are other designs that take care of the problem of uneven light distribution using deflectors and side mounted lights.
This takes care of the problem of plants in the center receiving most of the light at the expense of the plants located on both ends. This feature saves you the trouble of constantly rotating plants to gain maximum light and even growth.
The future of LED grow lighting
I think it’s clear that LED is the future of grow lighting. With the research being done and the constant improvements being made, I think by 2025 at the very most LED will have overtaken all other forms of grow lighting combined.
Every year there’s great advancements in designing LED light that is tailored specifically for the grow light industry. I would look for LED lighting improvements in ultraviolet ray production and increased flexibility in use and coverage.
I would also expect to see the alternative energy industry increasingly catering to the grower market by offering LED grow light/solar or wind packages that are designed specifically for the indoor farmer.
As it stands right now, yes, there is a higher initial investment with LED grow light systems. But that cost is quickly offset by the tremendous payback you get with the energy savings. However, as time goes by and LED lighting begins to take a majority share of the lighting market you can bet those cost is going to keep dropping to a more affordable rate.
It seems fairly clear, get used to LED lighting now because it is undoubtedly the future of grow lighting.
More About LED Grow Lights
LED (light-emitting diodes) grow lights are perfect for those that are looking to lead the charge. LED grow lights have rapidly come down in price and home growers everywhere are starting to make the switch to solely using them as their lighting option.
Maybe you don’t care about leading the charge, and you simply want a lighting system that produces extremely low heat, comes ready to plug-and-play, and can produce high yields with incredible energy efficiency. If so, look no further because LED is the perfect lighting option for you.
For calculating cost, expect to spend $1.50-$3 per watt depending on quality and brand. Remember that while most LEDs cost more per watt than HID lamps, they do not require a reflector or ballast. As well, LED lights last for decades where HID bulbs will often need to be replace every couple of years.
LED grow lights are available in different forms, so let’s look at the pros and cons of each so you can find the right LED light for you:
LED Panels
Most common type of LED grow light and most offer growers all they need for their lighting setup. They include heatsinks for removing heat, a driver (think of it as a ballast), and often come with a warranty.
Pros:
Usually full spectrum with switches for both the vegetative and flowering stage – can be combined
Comes ready to plug right into a standard house outlet
Incredibly long lifespan – the bulbs typically last for decades
Cons:
On the rare occasions, some units may require a 240V outlet
Most expensive type of the LED grow light
LED Bars
Many growers add LED bars as an easy way to expand their lighting footprint or change up their light spectrum. LED Bars are a single row of diodes that come in different spectrums.
Pros:
Can replace T5 fixtures for increase PAR and less energy consumption
Some units come plug-and-play ready and can be plugged into a standard 120V house outlet
Cons:
Usually only one spectrum with no switching options
Often they are only used for supplementing and multiple bars will need to be purchased if using as sole light type
LED Bulbs
Quickly replace all your old CFL bulbs with LED bulbs that will give you all the added benefits of LED grow lights.
Pros:
They will fit into a standard light socket
Great for mixing and matching for creating your preferred spectrum
Cons:
Multiple bulbs required
A reflective hood may be required
LED Light Spectrum
The best LED light spectrum is a controversial topic among growers. Most LED lights use a of mix blue and red diodes, with blue preferred for the vegetative state, while red light is preferred for the flowering stage. Blue and red light are used because these two lights drive plant photosynthesis while also being very efficient to produce. This leaves a large gap in the middle of the light spectrum with very few LED lights providing orange, green, and yellow diodes to cover said gap.
The debate lies in whether plants need these other colors. A plant can grow to incredible potentials with just red and blue light, however, despite the common belief, plants’ absorb green light. In fact, recent studies show that this light drives photosynthesis better than red. Unfortunately, green diodes are terrible at producing an efficient number of photons, and it’s best to avoid LEDs with them. This is why some growers still prefer HID lighting because HPS (High Pressure Sodium) bulbs spectrum delivers green, yellow, and orange light much more efficiently than LED creating a more efficient PAR spectrum.
1 blue diode for every 3 red diodes is a great starting ratio and will deliver the best spectrum if you could only use one for the entire growing phase. Those that are looking to replace their CFLs will love the Cirrus EVO for that reason alone. You’ll often see white diodes which are fine, however, you will want to know what the temperature color of white diodes are. If they are between 5200-8300K then they are preferred for the vegetative state. If they are between 2700-3,750K then they are great for flowering.
Why You Should Grow With LED Grow Lights
They may cause the most confusion among growers and offer a higher learning curb, but that’s not stopping them from dominating homer growers’ gardens. They are currently the most affordable light in the long run, the bulbs last for decades, and they are very easy to install.
Most growers will compare LED and HID grow lights when deciding which to use. Because LEDs are rapidly improving, it’s somewhat difficult to keep track of the gap that used to be between them. Most still believe that HID lights produce bigger yields per watt, but many growers that use LEDs believe they produce higher quality yields compared to HID grow lights.
Just make sure you keep these lights decently far from your plants: 1-2 feet. For the precise distance make sure to check the manual that comes with the lights. LEDs with 1W chips can be closer (12”), but it’s much more common that you’ll have 3W and 5W chips which will push your distance closer to 18-24” away.
LEDs are very directional and don’t spread out the light like a HID light so a PAR meter is advised. When used together you can easily create an even light footprint that beautifully covers your canopy that is unmatched by other lighting options. Using a light mover will greatly help with light coverage and avoiding hot spots.
Last, while considering wattage for LEDs is not as important as it is for HID lights (photosynthetic photon flux density and daily light integral are better metrics), a good general rule of thumb is 23 watts per square foot of growing area. So a 2’ by 2’ space would give you an overall space of 4 feet and will need at least 128 watts.