Susan WatkinsProfessor,Extension Poultry Specialist

Lighting significantly impactspoultry production. Too little lightingduring brooding or too much duringgrow-out can result in lost perfor-mance and profits. Solid side wall,tunnel-ventilated poultry barns aremore energy efficient to operate butdo require artificial lighting sources.The expense of lighting a poultry

barn with 60-watt incan-descent bulbs can be asmuch as 30%-40% of theelectrical operating cost($100-$250 a flock/ barndepending on barn sizeand flock age to market).Therefore, lightingimprovements should notonly be beneficial for thebirds but also energy effi-cient to minimize produc-tion costs.

Compact fluorescent bulbs (CFL)are commonly used as replacementsfor incandescent lighting. While thissource can save as much as 60% of thelighting cost compared to incandes-cent bulbs, industry wide, CFL bulbsin poultry barns experience high failure rates due to bulb sensitivity topower fluctuations. A second commonproblem with CFL bulbs is dirt accumulation on the spirals whichreduces bulb lumen light output, plusthe bulbs naturally lose light outputover time (lamp lumen depreciation,LLD). The bulbs also contain mercury,which is considered an environmentalrisk factor, so they require special disposal procedures. Cold cathodecompact fluorescent bulbs (CCFL) area second energy-efficient light source,but they are also sensitive to powerfluctuations, contain mercury and loselight output over time.

LED, light-emitting diodes, haveentered the market for poultry pro -duction in the last three years. LED

technology involves light emittingfrom electrons, and this light source isnow being used in broiler, turkey,layer and breeder production facilitieswith success. When brood lighting isadequate, bird performance with LEDbulbs is proving to be as good as, ifnot better than, performance undertraditional light sources. The LEDsare 80%-85% more efficient thanincandescent bulbs, and the well-designed technologies have had nofailures and are maintaining 70%-80%of their light output two years afterinstallation in broiler barns. Sincethis technology is a growing field withnew bulbs hitting the market at arapid rate, poultry producers inter-ested in LEDs should do their home-work before purchasing. The followingare key concepts to understand whenselecting any bulb:

1. Has the bulb been tested ordemonstrated in poultry barnenvironments?a. If yes, have results been

released to the public?b. What was bird behavior under

the lights? A consistent obser-vation by producers with LED bulbs is that the birds behavemore calmly, even when thelight level is raised from dimto full light. A possible reasonis that LED light does notflicker compared to CFL bulbs,which can flicker at a levelnoticeable to the birds. Poultryhave keen eyesight and aremuch more sensitive thanhumans to light flickering.

c. Is there any information avail -able regarding bulb efficiencyand long-term lumen outputor lamp lumen depreciation(LLD)? Do the bulbs have anEnergy Star rating from third-party testing? If applying forrebate programs for LEDs, it

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Poultry Lighting: LED Bulbs ProvideEnergy Savings and Durability

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Examples of LED bulbs

for poultry lighting

is important to confirm if the Energy Star rating is required or if only certain types oflamps qualify.

d. Have bulbs been cleaned under typical poultry barn wash-down procedures? Bulbswith an IP65 rating are actually rated forwash down.

2. What is the Kelvin (K) rating? Kelvin refers tothe color temperature of the light.a. 2700-3000 K – Warm Kelvin, orange-red color,

example – incandescent bulbb. 3400-3700 K – Neutral Kelvin, example –

Next Gen Ill. Poultry LED PL30c. 5000-6000 K – Cool Kelvin, blue-white color,

example – Once Innovation Agrishift LED

3. What are bulb lumens? Lumens are a measureof the total all-around light output. Bulbs like 8-watt cold cathodes with 325 lumens have very lowlight levels, whereas a 36-watt CFL could have2400 lumens, giving high light levels suitable forbrooding. It is also important to understand thatthe lumen rating that new bulbs have is usuallymuch higher than what some types of bulb tech-nology emit after 6 plus months in operation inpoultry facilities.

4. How many footcandles of light will my birdshave? Footcandles of light at the bird level is asignificant production tool to assure youngbirds start well and birds closer to market areminimizing energy losses. Footcandle is a mea-sure of the light intensity on a surface and helpsto standardize the value of light sources. A common standard for describing lights is lumensper watt. The order of magnitudes is incansescent15 lm/W, CFLs 60 lm/W and LEDs 75 lm/W.

Traditionally, newly hatched chicks havebeen given an average light intensity of 2 plusfootcandles for the first 4 to 14 days, dependingon strain and dietary program, with the majorityof light focused over feed and water lines. Oncebirds have started well, then light intensity canbe reduced. See your poultry company representa-tive for recommendations.

5. What is the light angle output? The more restrictive the angle of the light output, the more shadows will appear between lights and at thewall. LEDs were first sold mainly as spotlights,and light output was limited to narrow circles,making these prototypes unsuitable for poultryproduction barns where grow lights may belocated on 20-foot centers over feed lines. TheLED industry is now providing lights with awider band of light output better suited to poultry

production. It is recommended that the angle of light output should be a range of 120° to 160° tominimize dark areas in the barn. With incandes-cent bulbs, as much of the light went to ceilingsand walls as it did to bird level. For LEDS withthe light distribution less than 180°, light is nowdirected specifically toward the birds, hencereducing energy wastage on lighting unnecessarysurfaces.

6. How does the bulb get rid of heat? When thediodes are on, heat is produced. While far lessthan the heat of an incandescent bulb, this heatmust still be directed away from the diodes toprevent damage. There are at least two designscommonly used, fins or enlarged casing above thediodes. A third option is open slits to allow heatrelease. Openings for heat release can increasefailure risk of bulbs in poultry barns because ofdiode exposure to the production environment.

7. Are the bulbs compatible with dimmers andshould they be dimmed similar to currentlights used? Unlike incandescent bulbs whichdim in a linear fashion (meaning as the dimmer isturned down some percentage, the bulb outputdecreases the same percentage), most LED tech-nology dims on a non-linear basis (meaning thedimmer may need to be turned down significantlybefore a resulting dimming of the bulb occurs).New dimmers are being programmed to overcomethis. However, producers need to be aware thatexisting dimmers and LEDs may not be 100%compatible, and this may need to be addressed toassure uniform and proper dimming of lights.

8. Is the electrical system properly designedfor LED lights? Unlike standard incandescentlamps, LED, CFL and cold cathode lamps arenon-linear loads. Non-linear load are loads wherethe current is not proportional to the voltage. It isnot uncommon for lighting circuits to share acommon neutral conductor in poultry houses.Neutral currents from linear incandescent lampshave a cancellation effect, so the use of commonneutrals with incandescent lamp circuits makessense. It can reduce wiring costs. Neutral currents from the non-linear LED and CFL loadsdo not have a cancellation effect. In fact, the neutral currents can be additive. Be sure yourneutral current is adequately sized when non -linear LED and CFL loads are installed on cir-cuits using common neutrals. In new poultryhouse construction where non-linear loads will beutilized, common neutral conductors are not recommended. Check with a licensed electricianif there are concerns.

DR. SUSAN WATKINS is a professor and Extension poultry specialist with the University of Arkansas Division of Agricultureand is located at the University of Arkansas in Fayetteville.

Photo credits: Luma Vue bulb (L), NextGen bulb (R).

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