Welcome to David City
Welcome to David City
To enhance the vibrant community of David City by providing a tremendous quality of life defined by outstanding educational and employment opportunities for all citizens through provisions of quality, cost effective governmental services that include infrastructure, utilities, and affordable housing.
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My grandpa is so proud of the yard light on his farm. Installed in June of 1986, it has operated from dusk-to-dawn for more than 11,000 nights in a row. Grandpa loves bragging to his buddies at the coffee shop how it always has come on at sunset and off at sunrise. Sadly, I need to share news with him about his 175-watt mercury vapor (MV) yard light that he is not going to like.
After operating for over 130,000 hours, his MV light is producing less than 20 percent of its original light output due to lamp lumen depreciation. Even so, it still uses the same amount of electricity as the first day he turned it on. On a dark night, I can stand directly under the fixture and see that it is functioning. But when I pull a book out to read, I cannot even discern the chapter titles. This is simply the nature of MV bulbs or lamps. In fact, most MV lamps that operate from sundown to sunup lose 20 percent or more of their output in their first two years.
The disadvantages of grandpa’s MV light do not end there. If he shuts it off or if the power blinks, his light requires a “cool-off” and a “warm-up” period of five to seven minutes before returning to its previous light output. Moreover, MV lamp ballasts are noisy as his is always loudly buzzing when it is on. If my grandpa needs to replace the ballast in his fixture, he will find that under the Energy Policy Act of 2005, manufacturers cannot make or import ballasts for mercury vapor lights after Jan. 1, 2008. But, alas, his old ballast never fails.
So how am I going to convince Grandpa to send his MV light the way of the Dodo bird and install a new, energy-efficient LED area light? First, I will point out the money he will save by switching to a quality 40-watt LED. His current MV light uses about 880 kilowatt-hours (kWh) of electricity a year. At his average rate of 11¢/kWh, operating his light is adding about $97 every year to his electric bill. A quality 40-watt LED area light will only use about 175 kWh at a cost under $20 per year. With the purchase price of the new 40-watt LED area light around $120, his savings will pay for the new light in fewer than two years!
Next, I will point out how he is no longer getting the amount of light he originally paid for. After 8,000 hours of operation, his old MV light is producing only 80 percent of its original output. After 20,000 hours of operation, the 40-watt LED area light will still provide more than 90 percent of its original output. This is especially important since we tend to require more light to see as we age. Hopefully, this will appeal to Grandpa’s safety aspects.
Finally, if all else fails, I will make a plea to Grandma. Grandma has Entomophobia (fear of bugs). The vast majority of nighttime insects are photophilic (attracted to light). Most LED lights attract fewer insects than conventional MV lamps because they emit very little light in the ultraviolet part of the spectrum. Conversely, MV lights are heavy emitters in the ultra-violet spectrum which readily attracts swarms. If I inform Grandma of this fact, I have a feeling Grandpa will be installing a new 40-watt LED area light immediately.
Your local utility and Nebraska Public Power District want to help you make the best choices to brighten your nights. This commitment to providing you outstanding customer service includes helping you make the most of the energy you use throughout the year. For more ideas on how you can make your home or business EnergyWiseSM, contact your local utility or visit www.nppd.com.