1. FARM ENERGY Energy Fundamentals for Farm Lighting F ARM E NERGY PM 2089N

2. FARM ENERGY PM 2089N (USDA Census of Agriculture, 2007)

3. FARM ENERGY Proper lighting should: Provide a safe, effective working environment Deliver proper light level for animals Be energy efficient Be cost effective PM 2089N

4. Lumens: Quantity of light output (lm) Average rated life: Number of hours for half of the bulbs to burn out in lab tests FARM ENERGY PM 2089N

5. Efficiency: Lumens/Watt Example: –1200 lm/20 W = 60 FARM ENERGY PM 2089N

6. Foot-candles (fc): Level of light at a working surface One fc is amount of illumination from a candle falling on a surface at a distance of one foot FARM ENERGY PM 2089N

7. Incandescent Most common currently Least energy efficient Cheapest initial cost Shortest life Being phased out from retail −100 W – Jan 1, 2012 −75 W – Jan 1, 2013 −60 & 40 W – Jan 1, 2014 FARM ENERGY PM 2089N

8. FARM ENERGY Compact Fluorescent (CFL) 10 times more life than incandescent 75% less energy usage Should be rated for moist and dusty environment Enclosure globes can shorten life PM 2089N

9. FARM ENERGY Light Emitting Diodes (LED) Five times more efficient than incandescent Long rated life (near 100,000 hrs) Directional lighting Currently limited in damp or dusty environments Improving efficiency and costs every six months… stay tuned PM 2089N

10. Tube Fluorescent T 12 (1.5” diameter) −Phasing out (bulbs July 2012) T 8 (1” diameter) −4x more efficient than incandescent −< 12’ off floor −Mount electromagnetic ballast in weatherproof fixtures T 5 (0.6” diameter) −Shorter and more efficient than T8 −Only good in clean-dry environments currently FARM ENERGY PM 2089N

11. CFLType of LampIncandescent 23 WInput Wattage 100 W 69.6 lm/w1600 lm/23 WEfficiency15.8 lm/w1580 lm/100 W 67.2 kWh0.023 kW x 2920 hrEnergy Use292 kWh0.1 kW x 2920 hr $6.7267.2 kWh x $0.10Energy cost/yr $29.20292 kWh x $0.10 FARM ENERGY Economic comparison example: 23 W CFL (1600lm) vs. 100 W incandescent (1580 lm) Used 8 hours per day (2920 hrs) Electricity is $0.10/kWh PM 2089N

12. CFLType of LampIncandescent 23 WInput Wattage 100 W 12,000 hrsRated life1500 hrs 6,000 hrs50% of ratedAssumed life750 hrs50% of rated 0.49 bulbs2920 hrs/6000 hrsBulbs/yr3.9 bulbs2920 hr/750 hrs $3.19Cost/bulb$0.45 $1.56/yr$3.19 x 0.49 bulbsBulb cost/yr$1.75/yr$0.45 x 3.9 bulbs FARM ENERGY 23 W CFL (1600lm) vs. 100 W incandescent (1580 lm) Used 8 hours per day (2920 hrs) Electricity is $0.10/kWh

13. CFLType of LampIncandescent 23 WInput Wattage100 W $6.7267.2 kWh x $0.10Energy cost/yr$29.20292 kWh x $0.10 $1.56/yr$3.19 x 0.49 bulbsBulb cost/yr$1.75/yr$0.45 x 3.9 bulbs $8.28/yr$6.72 + $1.56Annual Cost$30.95/yr$29.20 + $1.75 $22.67/yr$30.95 - $8.28Savings 0.14 yrs$3.19/$22.67Payback FARM ENERGY 23 W CFL (1600lm) vs. 100 W incandescent (1580 lm) Used 8 hours per day (2920 hrs) Electricity is $0.10/kWh

14. S UMMARY : Adequate light level is important to meet basic needs in facilities in a safe manner There are multiple options for efficient indoor lighting Be aware of the impact of dust and humidity on light in your lighting decision Include initial cost of wiring and fixtures when looking for cost savings Appropriate disposal measures should be taken FARM ENERGY PM 2089N

15. FARM ENERGY F OR M ORE I NFORMATION : Google “ISU farm energy” or visit us online at http://farmenergy.exnet.iastate.edu Download ISU Farm Energy publications at no charge Follow us on Twitter @ISU_Farm_Energy for updates Ask your local utility provider to contact us! http://farmenergy.exnet.iastate.edu

16. FARM ENERGY http://farmenergy.exnet.iastate.edu