Building Your Own High-Power LED Grow Lights for Hydroponics

You will often hear in the world of hydroponic growing that Light emitting diode (LED) lights simply do not work as well as the traditional HPS (high pressure sodium) or Tungsten Halide lamps when growing large plants. The truth is that this belief is centered around the fact that most of the commercially available LED fixtures are built with low-power cascade LEDs that simply do not give your plants enough light intensity to grow properly. The fact that people do not know how to distinguish one from the other, coupled with the problems of getting a genuine, high power LED lamp makes the use of LED fixtures in hydroponics limited and almost never considered a serious option for modern growers. On today's post I want to talk a little bit about how you can build your OWN high power LED lamp and how this way you can get a cheap, low-energy, highly-efficient device to make your plants grow.

The first thing you need to consider here is the amount of LEDs you will be using (the amount you will require for your plants) and the power supply you will need to feed those little hungry fellows. From my experience I can tell you that the lumens measurement of high power LEDs does not give you an accurate estimation of how many you need since LEDs have a highly centered light spectrum that is more accurately measure in micro Einsteins (the appropiate measurement unit for these devices). In this case I advice an empirical measurement of 5, 3W high power LEDs for each plant you wish to grow and 1 blue LED for every 10 red LEDs. (below you can see a picture of one of my LEDs, the LED was dimmed to get a better picture)
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The second thing you want to do is buy the LEDs, just google red or blue 3W high power LED on ebay and you will find several chinese or US providers who will sell you these great artifacts for a small price. When you get your LEDs make sure you buy at least 3-5 more than what you will need since these LEDs are sensitive and they will burn easily if you wire them incorrectly. Since the power requirements of these LEDs are also pretty high they will get VERY hot (however much cooler than traditional lamps) and they will need to be mounted on aluminimum rails with at least one 6 inch fan for each 5 LEDs (or a BIG rail than can dissipate all the heat).

The next part - which is the most difficult - is the building of the power supply and voltage regulator side of the device. You can use a laptop supply to power up some LEDs but you need to calculate their power requirements so that you know how many you can power up for the power supply you will be using. A very good guide I used to create my LED assembly can be found here. Of course you should change the setup and LED number to fit your needs but the tutorial shows you exactly how you can choose the power supply, calculate LED needs and build the voltage regulator with a simple electronic circuit.
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Finally, after I finished I hooked the power supply of my LEDs to a regular appliance timer which sets them on and off at certain times of the day. Making sure that my basil plants get enough light for their growth even when I am not at home. It is very worth noting that before I installed this LED fixture my basil plants were extremely leggy, etiolated and just dying. A few days after the LEDs where in place they started to grow like crazy :o) Do you have any questions, comments or suggestions ? Have you also built your own LED fixture ? Leave a comment below !

Choosing a LED Grow Light for your Hydroponic Crop

One of the most common problems faced by urban gardeners who want to deal with hydroponic crops is lack of light. Generally plants need very large amounts of light to grow which can only be given by very powerful and expensive lamps which also have the big draw back of consuming large amounts of power. The solution - now readily available - is to buy light emitting diode (LED) lamps to deal with a very efficient yet low consuming light source for your plants. On today's post I want to talk to you about how you can choose your light emitting diode lamp for hydroponic growth and what lamps you should definitely avoid if you don't want your crop not to be a total failure.

So what is so expensive about current lamps and so great about LEDS ? Currently the traditional way to supply artifical light to crops has been the use of full spectrum lamps which can be either tungsten metal halide or high pressure sodium (although sodium lamps have a much narrower spectrum). These lamps are very inefficient - wasting most of the power given to them as heat - and therefore consume great amounts of power. A high pressure sodium lamp (HPS) needs to consume about 400-700W to be able to sustain an average tomato plant. The truth is that most of this energy is wasted as heat and almost none of it (around 20-40W of light) are actually absorbed by the plant.

Here is when LEDS come to save the day. Light emitting diodes are very efficient in generating light from electricity (wasting only a small fraction of the energy as heat) and they also provide light in very narrow ranges which can be tuned to only supply the wavelengths needed by plants. The reason why plants are green is because their main photosensitive pigment is chlorophyll (there are several types by the way), a pigment that absorbs red and blue wavelengths and reflects green. With this in mind - not only are LEDS able to supply your hydroponic plants witha higher efficiency - but they are also able to provide your plant with only the colors of light it needs. Achieving a double gain in efficiency. As a matter of fact, a LED lamp with just 60W is enough to grow a tomato plant.

However, not all LEDS are created equal. Many people think that all LED lamps are the same and they end up buying cheap LED lamps or panels that simply do not provide plants with the energy they need to grow. There are generally two kinds of LEDS available for lamps. The first kind - low power LEDS - are the type of lights used to make your computer and keyboard lights. These lights are weak and they are usually sold in the forms of panels with HUNDREDS to make them appear "useful" for hydroponic growth. The second - high power LEDS - are lights used for traffic lights and high power applications and they ARE the type you need for hydroponic growth.
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In general, when you are looking to replace your TMH or HPS lamps with LEDs you need to look for high power LED lamps in the range of 50-100W for each 400W lamp you want to replace. You also need to look at the red to blue light ratio since different plant varieties need different proportions of light. If you are growing plants that need to have flowers then you will need to aim for a red to blue ratio of about 8:2 while plants that do not produce flowers may grow well with only red lights. This is - of course - a very course guide to the light color ratio but it may guide you well when you are looking for lamps for a certain crop.

With this small guide and knowledge you will be able to eliminate most lamps that do not work and buy high power LED lamps that will deliver and provide you with a much more efficient, cooler and more eco-friendly way to provide your hydroponic crop with artificial light.