The choices regarding LED grow lights are becoming greater and greater. Which is great news for the indoor gardener, but it can also get a bit confusing and making a decision can be difficult.

Photosynthesis:-

The main ingredients for photosynthesis are light, carbon dioxide and water. Plants require specific ratios of light for photosynthesis as they convert light energy into plant energy in their chloroplasts. The chloroplasts produce Chlorophyll A and B, the two primary compounds that drive photosynthesis. These compounds absorb primarily blue and red light, more specifically, 439nm, 469n, 642nm and 667nm. LED's allow us to target narrow wavelengths of light to be specifically tailored to provide the "light" ingredient for photosynthesis. Unlike traditional lighting, such as CFL or HIDs which emit the whole spectral range, LED grow lights have been scientifically tailored to emit only the spectral wavelengths required for photosynthesis, thus, plants use 95-100% of the light emitted, with little to no energy wasted.

They come in 2 colour types one tailored for Leaf development (more blue light) & one for Flower & Fruit (more red light).

1.    Leaf development:- a Blue dominant White, consisting predominantly of white LEDs which have most of their energy in the 460nm region, some warm white for 440nm and some red (630nm and 660nm).

2.    Flower & Fruit development:- a Red dominant. Producing flower and fruit basically requires a mix of about 1/3 blue to 2/3 red as you look around the Internet you'll find many different opinions on which particular frequencies are required. You'll see one light which is very popular in the US and it has LEDs specifically at these frequencies Red (660nm, 630nm) + FarRed(740nm) + Blue(470nm, 440nm) + Green/Orange(525nm) i.e. 6 band, and then you'll see other ones which are 4 band, consisting predominantly of 660nm red along with some 630nm red, and 460nm blue, and some warm white, we have used this configuration in some of our lights, the main reason we included the warm white is that, they give energy to the 440nm chlorophyll peak & also a sprinkling of frequencies right across the light spectrum, including as you can see, in the orange part of the spectrum, that’s why they appear white, these frequencies appear to be like trace elements, as they are only needed in small amounts. But then again the picture at the bottom which shows 45x 2w 1200mm long  lights growing plants to flower, in the picture it is just made up of 6x 630nm + 3x 6000kWhite using 90° lenses.

So basically as long as you have the intensity and around 70% to 30% red to blue you will get good results.

You will often see reference to PAR which stands for Photosynthetically Available Radiation. The PAR unit of measurement is called a micro mole, which expresses the photon flux density of light per square meter. Most plants tend to grow faster when available light increases, however their maximum growth rate is achieved at a substantially lower amount then that of sunlight being 2,000 micromoles(mid day clear sky). The point at which a plant receives more light than they can utilize, is known as the Light Saturation Point. For most plants, the optimum level of PAR lighting is approximately 500 micromoles per square meter (~55 micromoles per square foot), and if the plants receive much over that, they can reach the point of light saturation. In some instances, plants have been observed growing slower when exposed to excess amounts of light, vs growing in their optimal range.

LEDs Power rating e.g. 1W vs 3W

In the world of LED Grow Lights, the most common LED chips are 1W and 3W diodes. The labelling of these diodes however, confuses most people as they expect the name of the product to match its power consumption. With LEDs however, this is not always the case. The wattage of a LED is determined by the amperage they are driven at, with 1W LEDs driven at 350mA, and 3W LEDs driven at 700mA. Despite the fact that 3W LEDs are driven at double the amperage of a 1W, and normally consume only 2W of actual power, LED manufacturers have labelled them a 3W. It’s easy to ask yourself “then why did LED manufacturers name these LEDs 3W instead of 2W?” Perhaps it is simply a marketing trick, or just a label meant to confuse us. Whatever the reason it is important to note that anything labelled a 3W LED, is by all intents and purposes a 2W LED.

3W LEDs are only marginally less efficient than 1W LEDs when you compare the actual power consumed to lumen output. So 3W LEDs are best driven at 550-600mA, or about 1.6W per LED. The reason the LEDs are not driven at 700mA as they are rated, is that it reduces the efficiency, increases heat, and reduces lifespan. At 550mA the 3W LEDs test 5% more efficient in terms of lumens per watt than at 700mA, run up to 15 degrees cooler, and last much longer.

Be careful however, of companies using 3W LEDs to trick you with their marketing.

2W-2chip/3W-3chip LEDs

2W-2Chip and 3W-3Chip LEDs are classified in the "Multi-Chip Emitter" category. These LED's are not your traditional 2W or 3W LED, which function with a single emitting diode. Instead multi-chip LEDs use multiple 1W diodes under a single lens. Since 1W LED's are the most efficient of any LED in use, most people assume that these chips are just as efficient, if not more efficient because they utilize multiple 1W diodes. When you start to break down these LEDs however, and examine exactly how they are being used, higher efficiency is certainly not the case.

Due to heat restrictions, 2W-2Chip LED's are presently being driven at 400mA and 3W-3Chip LED's at 500mA. Now since each LED contains multiple 1W chips, the amperage being supplied must be divided by the # of chips to determine the amperage of each chip. For 2W-2Chip LED's this equates to 200mA per chip, and with 3W-3Chip this is just under 170 mA per chip. In relation to the amperage a 1W is supposed to be driven at (350mA), each of the chips in the 3W LED is receiving under half the rated amperage, with the 2W LEDs coming in slightly above half! So instead of using a single 1W LED at full brightness, many manufacturers are now using multiple 1W LED's at half brightness under 1 lens in order to create the illusion of more light! however, more light is most certainly not the case, and dimmed LEDs will never deliver the levels of penetration achieved with full brightness LEDs.

The reason why each chip is run at such a low amperage is because when the amperage to each chip is increased, the lifespan and output is greatly reduced, or the LEDs would burn out completely!

So why do we sell 2 & 3 watt LED lights, the ones that we sell have the LEDs mounted directly on the aluminium backing plate which gives excellent heat dissipation, and you will get more light from a higher wattage LED ie a 2W is brighter then a 1W, it is just that it will not be 2 times greater, however the price performance is now such that they are worth considering i.e. when they are driven at below their maximum rated current and they have good heat sinking designs, than they are generally, but not always, a more economical purchase.

Summary:-

A 2W is approx. 1.5 x as bright as a 1W & A 3W is approx. 1.7 x as bright as a 1W.

Eg the 126x3w at 10cm has 1700mml & the 126x1w at 10cm has 1000mml using 60° lenses. Meaning that a good height and coverage for the 126x3w would be 30- 40cm (9-18 inches) above the plant canopy for a coverage area of 46cm x 76cm, (18" x 30"). So if you are using the same light in a 1W configuration then you would decrease the height and have a slightly smaller coverage area.

What we look for is value for money, reliability and choices with regard to different growing criteria. So if you look at the lights that we are offering there are basically 3 groups but as you will see some of them overlap.

Pic Group 2:- The most common LED grow lights, eg the UFO series consists of 1, 2, 3 or 5watt LEDs, which have a standard internal lens of 120° i.e. wide-angle. The biggest advantage of these light is generally their price the ones we have chosen for this category also have the feature of being able to switch between a vegative stage and then bring in the remaining lights to boost intensity in the red spectrum for the fruiting stage. e.g.

LED-Grow-Light-144x2W

LED-Grow-Light-45x2W

Pic Group 3:- A 2nd type of light are those that use lenses to focus the original 120° spread into a small beam therefore increasing the intensity of the light. The obvious advantage of these lights is that there is no wasted light going to the sides and the light that the plant's underneath receive has more energy i.e. higher intensity. e.g.

LED-Grow-Light-126x3w-6-Band

LED-Grow-Light-45x3w-Lens-No-Fan

Pic Group 4:- A 3rd type of light, which may or may not have additional lenses, is categorised by not having a fan and therefore having its power supply mounted remotely. The no noise operation and the lighter weight of this type lights make them extremely flexible, they also have a higher level of water resistance so they are safer. These features make them extremely versatile when growing in your living area. e.g.

LED-Grow-Light-2x18watt-Red

LED-Grow-Light-2x18watt-Blue-White

LED-Grow-Light-4x9watt-Blue-White

LED-Grow-Light-4x9watt-Red

LED-Grow-Light-45x3w-Lens-No-Fan

LED-Grow-Light-27x3watt-Red

LED-Grow-Light-27x3watt-Blue-White

Pic Group 5:- LED Bar lights - Firstly this is a new range of lights, we believe they have much more flexibility and reliability and takes the whole concept of LED lighting to a new level, allowing you to tailor a solution to your specific needs.

Some features:-

·          no fan i.e. silent operation.

·          External power supply, easy to replace if a problem.

·          Can be arranged in many many different configurations e.g. use 2 red strips and 2 blue/white strips for early-stage development of a tomato plant and then when flowering begins change the blue/white strips to red.

·          Because the power supplies are external the lights are very light and can be easily arranged around your plant to give maximum coverage.

·          They can be used with or without lenses.

·          The lights themselves and the connectors are water-resistant.

Lifespan

The lifespan of 50,000-100,000hrs (that you are probably seen on the web somewhere) refers to when the LEDs will begin to fail, what is more important is when they will lose enough intensity to no longer produce the results you require. And again this primarily depends on heat and duration of the on Time.

A realistic estimate for LED grow lights with good heat sinking design would be to maintain above 80% intensity for 30,000 hours when operated in a room temperature of between 20 and 30°C for 10 hours per day, which is just over 8 years, 16 hours per day, which is just over 5 years. Of course they will keep working after this for a long time.

If you would like more information and are interested in purchasing these lights whether for retail or personal use please contact us at info01au#livingapartment  Note change the # to a @ and add .com (spam problems).

For international customers click on -> International Sales

For Australian customers click on -> http://www.livingapartment.com.au/Products/Salad-Greens-Under-Lights