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erik
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Hello Maximum Yield,
It seems like there are more and more articles, forums and gardeners talking about LED grow
lights these days. There are lots of different opinions out there. So far you guys have never
steered me in the wrong direction. So what do you think? Should I consider replacing the HPS
light in my hobby garden with one of the higher output LEDs, and what kind of results should I
expect if I do?
Thanks, Fredo
Fredo,
I always do my best to help keep the readership informed
and up-to-date on the many new technologies that are
emerging for indoor growers. It takes a while to draw accurate
conclusions about new technologies, and often while we are
trialing the latest and greatest, the technologies being tested
are advancing. So, sometimes our data becomes obsolete due
to improvements or changes in the technologies being tested.
I expect to see lots of advances in LED (light emitting diode)
lighting for horticultural crops in the next while. This may lead
to some major changes in the way people grow indoors, and
the number of people that grow indoors; possibly paving the
way to a horticultural renaissance of sorts.
My conclusions regarding LEDs are only as up-to-date as the
time of this writing. By the time you read this in print, there
will likely be more advances in the way of LEDs.
At present, high output LEDs, which typically range from 0.3
watts up to 3.0 watts (per diode) are capable of producing very
healthy plant growth. The higher the wattage of the diode, the
more light they can emit; resulting in better cropping potential.
Firstly, power consumption for lighting is drastically reduced,
typically by up to six to 10 times! Now factor in that the
diodes and fixtures emit negligible amounts of heat, and you
further reduce your electrical consumption that is associated
with keeping temperatures in the optimal range with exhaust
systems or air-conditioning. The initial cost of an LED fixture
is quickly offset with the savings in electricity, and the fact
that cooling equipment purchases and power consumption are
greatly reduced or eliminated.
So far it has been found that using one of the higher end
high-output LED plant lighting systems comprised of one
watt or greater per diode for a total of near 100 watts total can
help to give results comparable to a 250 watt or even 400 watt
HPS lamp. While the electrical savings is very significant, the
fact that the lighting does not heat up the growing area allows
for very efficient use of supplemental carbon dioxide; offering
the potential to increase yields.
Because they are so cool running and the fixture requires
very little space, you can set-up an LED lit garden in just about
any space that is tall enough for your desired crop. Best of all,
your garden can run near silent, as minimal air movement and
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exchanges will be required. Lots of growers find that using
LEDs help to reduce their watering requirements also.
However, while it has been noted that LEDs em