Free Article HomeSubmit Article l Contact Us


Growing Plants with LED's 
In some dictionaries life is defined, as a power that demonstrates a purpose to feed, process matter into energy, grow, and reproduce. Life means existence, a state of being. No matter how we look at the definitions, one thing is clear: life is the energy driving the universe and all its happenings, and for humans and all the living organisms, life, or being alive, is a force entirely dependent on special factors such as air, water, light and much more elements that interact to support existence in all its forms and each of them is equally important for the survival of the species...

All these resources are an abundant presence on Earth, but nothing can last forever. Polluted water is not usable, air is itself contaminated on many parts of the Globe, mineral resources are non-renewable and light… natural light has its benefits but also it can constitute a danger for the species if we consider the UV emissions reaching Earth’s atmosphere.

Light influences all life on Earth directly or indirectly. Plants need light for photosynthesis, therefore for growing and in exchange they forward their energy to the animals that consume them. At the same time animals need light for a harmonious evolution and even nocturnal ones require some low level illumination. Lack of natural light causes various disorders by people and the same happens by plants and animals.

UV light can harm living organisms in several ways. For example plants overexposed to UV light reduce size and are more susceptible to specific diseases. The light coming direct from the sun sends to earth three types of ultraviolet: UV-A (380-315 nm), UV-B (315-280 nm) and UV-C (280-10 nm). Due to the absorption in the atmosphere's ozone layer, 99% of the ultraviolet light that reaches the Earth's surface is UV-A.

While UV-A causes plants only a little harm, UV-B, which is a shorter wavelength, can damage plant tissue and in humans it can cause skin cancer. UV-C is the part from the UV spectrum with the shortest wavelength and all bacteria and virus get deadly sunburn in an artificial UV-C filter system. Certainly UV light has its paradoxes: even if it is harmful in one way, it is useful in another. Medicine is using this artificial UV light to cure difficult skin conditions such as psoriasis eczema, lymphoma, acne, a-topic dermatitis, and so on.

Fact is that plants don’t need too much UV light, on the contrary. This is why crop production with artificial light means that will eliminate the dangerous UV emissions seems to be the next logical step.

Growing Plants Technology - Crop Production Systems

The target of crop production systems is to develop innovative technologies that lower the costs of harvest and ensure ecologically aware crop farming.

The crop production systems do not disregard important factors that influence plant development: temperature, humidity, light, carbon dioxide, water and nutrients. All these blend to create the ideal environment for a plant to grow and reproduce as well as they influence size, seeds, plant health and so on. Each plant will progress in its own manner, depending on the environment. Since a long time already biologists are studying the factors that influence vegetation’s evolution. Light is a very important factor and researchers were able to determine exactly which wavelengths are the ones plants need for their growth. Some colours in light rays are essential for good plant evolution. Vegetation mirror and receive a small amount of energy from yellow and green emissions of the visible spectrum. However the red and blue fractions of the light continuum are the most valuable energy resources for plant life, and plants necessitate more red (625 to 675 nm) than blue (400 to 470nm). Yellow (525 nm) triggers photosynthesis too, while IR influences seed spurring and UV colour and scent.

How Light Colour Influences Plant Growth

Blue light: plants react to the intensity of blue light. Lessening the blue light will cause poor growth – the strength of the radiation in any other part of the spectrum is not as important as the intensity of the blue, which shapes height and quality.

Red (660 nm) and infrared (730 nm) (also known as IR or far red) light: Intensifying the total of IR in relation with 660 nm red makes plants grow tall and thin. On the other hand if red is increased while IR diminished, plants will be short but thick. Plant reactions are not linear with the red/far red ratio and they can also vary in their response to red and far red light.

Ultraviolet light (UV): While overexposure is dangerous, small amounts of UV light can be beneficial for the flora. In many cases UV light is a very important cause for colours, taste and aroma. But UV-C and UV-B are believed to stop plant spread and this is why they have to be removed from the light under which plants are developed in green houses by UV stabilisers or glass. Removal of the UV up to 400nm is might be effective also in case of virus carrier insects (as insects see partly in UV).

Direct light from the Sun distributes the useful wavelengths only on special times of the day and in small quantum enough for a harmonious growth in some parts of the Earth, yet not enough on others.

Crop production systems are dealing with such problems and find ways to replace natural light with artificial light. The idea of growing plants under artificial illuminators is not new at all. Long time ago NASA started to grow plants in space, and the results were astonishing. Nowadays we know that by using the correct wavelength plants develop harmonious and healthy, sure if they have all the other conditions ensured. Yet getting light of the correct wavelength is not an easy task, especially if one takes into account the costs and efficiency of such light sources.

LED Lighting Technologies to Substitute Natural Light

To substitute natural light is quite difficult also if you consider how hard it is to obtain light near the visible part of the spectrum with traditional luminaries. Light emitting diodes are here to change that difficulty.

SSL (solid state lighting) is the youngest lighting technology and by now is believed to be more efficient than incandescence and fluorescence due to the fact that SSLs produce light at or near the visible part of the spectrum and as a result the emitted light can be used straight or with minor conversion. One of the most important advantages is that SSL technology has eliminated damaging components from the light sources (remember: light emitting diodes contain no ultraviolet unless they are produced as UV LEDs).

NASA is already using SSL in its space farming systems. The reasons are quite simple: incandescent or fluorescent lamps are not efficient enough for such purposes, because they consume a lot of electrical power, generate heat and contain electrodes that burn out (maintenance costs are high). This is why NASA’s plant physiologists started to work with light emitting diodes (blue and red) to grow salad plants such as lettuce and radishes. The researchers found our that blue and red light is essential for plant growth and, in general, a percentage of 8% blue LEDs and 92% red LEDs, both with the same frequency and relative intensity per LED, are enough for a harmonious evolution. Blue has a smaller influence than red; however a percentage between 1% and 20% of blue light can be selected, depending on the plants and their growth requirements. The NASA scientists have tried to create the most cost and energy efficient light sources possible, and this is why they have eliminated from the fixtures other colours normally found in white light. "What we've found basically is that we are able to limit the amount of colour we give to the plants and still have them grow as well as with white light." said the research scientist Greg Goins of Dynamac Corp. LEDs are not the only ones efficient for growing plants: sulphur microwave lamps are the most efficient light sources known to man, that can generate as much light as the noonday sun, perfect for illuminating large-scale systems such as greenhouses. For smaller applications, such as indoor gardens, LEDs seem to be the right choice.

Pros and Contras LED Grow Light Systems

There are some pro and contras when it comes to LED grow light systems. When planning such farming alternatives, one has to carefully consider that plants do use light at all wavelengths from UV to IR, as explained above, needed to convert water and carbon dioxide into sugars. Some plants use more red and blue, less green and yellow, while others use green as much as they use red and blue, as well as the light in between. If LEDs are chosen for brightness, there is one aspect to be underlined: they just look bright because their light is unidirectional and their size is small. To get enough light there are many LEDs needed, that’s why the cost of LED arrays or LED modules is so high. LEDs can be calibrated to emit only the light most efficient for the plants, but not all the light plants need. This is why such light sources are recommended only in places where direct light from the sun is not enough or inexistent – space farming for example. Also in places where light from the sun is too strong and can harm the plants with the high emission of UV, LEDs are a good choice, because UV filters are stopping some of the useful wavelengths too. In wintertime the weather conditions restrain crop production; this is why greenhouses need a substitute for the natural light. It makes sense to deliver plants the minimum lighting conditions for a corresponding evolution.

There are some significant factors to take into account when choosing light sources for such applications and these are low costs, energy efficiency, long life, and ability to withstand voltage fluctuations, modularity in order to grant users the possibility to assemble arrays that gives as much light as needed, where needed. LEDs are pretty efficient in the conversion of electric power to light, in any case more than traditional fluorescent and incandescent lamps. Due to the fact that light emitting diodes can be manufactured to emit a specific wavelength and are expected to have a long life span (from 50000 hours up), many plant physiologists are considering using them in large applications. Compared to LEDs most of the other traditional lamps have to be replaced every two-three years. Other features such as choice of viewing angles, control options, instant turn on times, cold start and much more, recommend the semiconductor devices. At present this is still an expensive technology, but in time LEDs efficiency will be maximized while prices reduced and these details are a good base for future planning.

My-tronic GmbH to Produce LED Grow Light Systems on Request

It is so far clear that in order to produce efficient LED grow light systems a lot of investigation is necessary. It is not enough to mount some blue and red LEDs on a PCB and say: “that’s it; we’ve got the plant growing LED system”. NASA created only a mechanism that delivers the minimum amount of light needed for some plants. For greenhouses on Earth other questions need to be answered: how much blue, how much red? What about the other colours, what about UV and IR? Should the light pulse? Should it be dimmed in the morning and evening to imitate natural conditions (sunrise and sunset?). Do plants need light at night? And the list remains opened.

At my-tronic GmbH there are no plant physiologists, but only engineers ready to bring their technical expertise to scientists in order to build the best light sources for LED plant growth systems. The domain is still new and can be considered a challenge for any researcher. Still my-tronic’s engineers know exactly which are the LEDs’ limitations, what can be done with such devices and what not. And the company’s motto: “bringing light in your lives” is also a statement of commitment to life and development.

Author Info:

Mihaela Lica started her career as a reporter for the National Romanian Radio Station, worked as a PR Referent in a bank, later used to work as a military journalist for the Romanian MoD and now she is the PR and Media Manager for the German company my-tronic GmbH.

 
30 Most Recent Articles :
A Disputed New Business:Virtual Property Exchange

In many ways, the in-game economy is similar to a real world economy - goods and services are traded to mutual advantage and are mediated in currencies(gold,platinum,credit,etc.). An online broker, who goes by the screen name Rolala, was not a fan of online games until his 15-year-old son be[ Read Article]

THE UNITED STATES, A Terrorist Nation

I love the United States of America, but I cannot tolerate the UNITED STATES OF AMERICA. No I am not shouting at you, I am simply making a distinction, a difference that thirty-seven states of the union have noticed and moved to rectify. You see, AMERICA isn’t America anymore, nor does it in anyw[ Read Article]

Dollars and Sense

When I speak of the Federal Reserve and the fiat monetary system that controls our lives I feel as though my words are falling on deaf ears. I have the sense that the simplest conversations suggesting that change must be made invoke fear and condemnation from my fellow citizens. When will we tak[ Read Article]

Constitutionality

Is the 16th Amendment constitutional? Of course it is, the Supreme Court has made that as clear as it did the issue of slavery. But let us remember that it took the lives of more than 365,000 brave American men and the destruction of the Republic to wrest the matter from the courts and resolve the[ Read Article]

Five Secrets to Effective Pay-Per-Click Advertising

With so many companies swarming the World Wide Web with their products, how can you and your products and services stand out? Your ready answer would most likely be effective marketing. But how? How can you catch the eye of a surfer skimming carelessly through web pages? How can you keep the at[ Read Article]

How to Sell Bonds

If you want to make good money with banks, or any institution, Government and agency bonds are where it is at. Simply because all Government bonds and agencies are AAA rated, and banks can buy millions of dollars of any bond without incurring any credit risk. All banks own bonds of some sort, a[ Read Article]

Closing in the Car Business

The “P” Word. Closing is all about helping car customers make positive decisions. It is not about pressure or manipulation. Your customers need help overcoming the “P” word. Procrastination! Procrastination is natural when it comes to making a buying decision. Your customer is trying to avoid [ Read Article]

If You Build It They Will Come, or Will They?

All right, so you invested your time and energy to build your organization a great new web site, but you are not getting quite the results you were hoping for. Few customers are visiting or interacting with you and rarely do you get prospects to contact you through the site. So what can you do to [ Read Article]

Confessions of a Yoga Teacher

The following are questions that Yoga teachers still need to answer, despite overwhelming evidence that Yoga is ?the mother of all health maintenance systems.? Mainstream thought is finally catching up, with the progress Yoga is making, but it has taken 5,000 years for us to get this far. Serio[ Read Article]

Vertical Creep in Search Results :: Should Organic Optimizers be Concerned?

I thought for this week I’d give a summary of some of the more interesting Search Engine Strategies sessions which are currently going on in New York City. I was at SES as a speaker last year in New York and I have to say, there is a wealth of information there even if some of it is contradict[ Read Article]

How to build link popularity fast and free

We all knew that back link or link popularity is a big factor to get good position in any search engines. But building link popularity some times really hard if you don't know how to do it. One of the hardest problem for new webmasters is to get back link to their newly stablis[ Read Article]

Does Chiropractic Care Really Make Sense?

The Role of Chiropractic in Treatment Beyond the Resolution of Symptoms Do you have the same nagging injury that never seems to go away? Are you suffering needlessly with pain? Are you fed up with taking painkillers? Do you want to find out what is causing your pain? If your answer is ‘ye[ Read Article]

The Economic Implications of Buying Drugs Online

Although the Internet is fairly new (at least to the mainstream) online shopping has grown by leaps and bounds. Now you can buy almost anything you need, from food to fishing equipment, right through your computer. Of course, this has meant that commerce has been forced to adapt to the changing co[ Read Article]

Manning and Manning-Can Either Brother Win the Big One?

It was just over a year ago, after the Colts lost to the Pats in their post-season contest, that Boomer Esiason said on national television, "I think maybe Peyton (Manning) is this generation's Dan Marino." Esiason went on to state that Manning "is a great football player, but he's not going to get[ Read Article]

Branding, Branding, Branding - MSN fails to keep it Straight

Sometimes you see promotions come along and you wonder: did they just do that? The current MSN promotion called msnsearchandwin is a prime example of this. Not only do they use “black hat” or at least “questionable” tactics on the site, but the messaging is inconsistent. In this article [ Read Article]

The New MSN Search Interface :: A positive change or the antithesis of transformation?

Now, instead of wide blue bars there are sleek silver-grey bars. Also, the top bar where the search box is became narrower. To me this makes the page seem less “closed in” and more visually appealing. I now feel as if I can trust the results more because they have more room. I’ve also noti[ Read Article]

Malta Holidays

With Malta visitor numbers static in recent years and facing new competiton from former Eastern Bloc countries offering cheap holidays, the recent announcement by the Maltese government that negotiations were at an advanced stage with two low cost airlines has[ Read Article]

Drug Rehab Treatment Centers as an Experience, not a Punishment

Choosing a drug rehab treatment center is a decision that calls for both negative and positive emotions. Nobody wants addiction to overtake their life to the point that rehab is the necessary step. However, the decision to go to one is something to look forward to, as it is the decision to rebui[ Read Article]

Some ways to improve your king content

There are thousands of articles, books and forum posts which showed that content is king in search engine optimization (SEO). In this article, you can find some ways that can help you improve this king content for your web site. * Content for people first, not for search engines - Some webmaste[ Read Article]

Aerosmith Just Keeps On Rockin’

For over three decades, Aerosmith have been one of rock's most revered and popular bands, crafting classic songs full of raw guitar runs and intensely energetic vocals. The band first reached fame in the 1970’s with a string of hits including "Dream On," "Sweet Emotion" and "Walk This Way." During t[ Read Article]

Chicago Cubs Pitcher Mark Prior Re-signs

After many trips through the rumor mill, Mark Prior accepted the Chicago Cubs’ offer on January 27 to a one-year, $3.65 million contract. That is $900,000 more than the salary he would have earned under the contract he voided in November. Since Prior's definitive season in 2003 (18-6), he has cooled[ Read Article]

Social Networking - The Next Great Marketing Medium?

There has been a virtual explosion of social networking sites in the past couple of years. Even the big players like Google, Yahoo and MSN are getting into it. With so much interest in how social networks work, one begins to wonder if there is marketing potential within these social network[ Read Article]

How to choose paid directory for web site listing?

How to choose paid directory for web site listing? Search Engines are the major source of traffic for any website. High search engine ranking can boost number of your visitors and in turn leads to increase in sales. The best way to get top search engine placement is to improve link popularity [ Read Article]

Addiction Treatment Centers Using Experiential Therapies

Life is experience. Substance dependence overtakes a person’s ability to make her own decisions to experience life, and life is no longer actively participated in. Therefore, in overcoming addiction, it is vital to learn to re-experience life. This lesson helps a treatment center resident reint[ Read Article]

The DH: Making Life Tough for AL Pitchers

In 1973 Major League Baseball instituted three rules designed to lessen the power of pitchers and create more offense. One theory at work was that the game needed to be energized and that more hitting would create additional runs and excitement. Both the National and American Leagues lowered th[ Read Article]

Vacation on the Beach the Smart Way

Vacation on the Beach the Smart Way Almost everyone agrees; there is no more relaxing way to vacation than to take it to the beach. For the vacationer/traveler who hasn't considered a beach house rental before, they represent an affordable and fun family oriented alternative. There is an intell[ Read Article]

Malta Holidays and Hotels Buzzed by New Jets

With Malta visitor numbers static in recent years and facing new competiton from former Eastern Bloc countries offering cheap holidays, the recent announcement by the Maltese government that negotiations were at an advanced stage with two low cost airlines has sparked hopes that the island will see [ Read Article]

The Rising Cost of Prescription Drugs

If you’re like many Americans, the rising cost of prescription drugs may be costing you your health. In particular, seniors living on a fixed income with no insurance are finding it difficult to pay for necessary prescriptions out-of-pocket, and as a result, may be failing to receive the treatment[ Read Article]

Who's Tops in Hockey and Who's Not

The National Hockey League needs to do more to encourage better coverage of the hockey games. With so many other sports realizing national coverage, the NHL is sometimes forgotten. However, this year, there's a race for the Stanley Cup, and only one is set to win it. But which team will that be? [ Read Article]

The Danger Of Rounding Up Your Debts

Rounding up your debts is one of the biggest dangers to your financial position. It's also one of the easiest ways for your debts to get out of control. This way of thinking is best summed up by the following comment; ‘I already owe $27500 so what’s another $500. It takes my debt to a nice round [ Read Article]

 

World Top Stories :
XML error: not well-formed (invalid token) at line 7