Decorating for the holidays – LED vs. Incandescent

The Griswold House from National Lampoon's Christmas Vacation

The Griswold House from National Lampoon’s Christmas Vacation

It’s that time again and Christmas displays are popping up in and on homes all around the world.  As we watch retailers like Home Depot and Walmart reduce prices on LED light bulbs, the same is happening with LED Christmas lights.  So, is it time to make the switch?

Depending on your tastes, LED lighting for Christmas holiday decorating can be a quick affair with a few strings of lights on your Christmas tree or can be a large artistic expression in light on your home like you’re Clark Griswold of National Lampoon’s Christmas Vacation movie.

Let’s take a look at some of the facts.

LED lighting for the holidays is safer – they’re not hot to the touch, so they won’t start a fire, especially if lit for a long period of time. They’re sturdier and made of epoxy lenses rather than plastic or glass like traditional incandescents.  They’re longer-lasting and could be in use 20 or even 40 years from now.  And they use less energy (about 80 percent) so that you can connect more strings together in series without blowing a fuse (your’s and the lights).

You might remember the moment in Christmas Vacation when Clark Griswold turned on the Christmas lights on his home (decorated with 25,000 incandescent imported Italian twinkle lights) and caused a major power outage in the city of Chicago.  While you might not take out your local power grid, you might be concerned with your electric bill if you tend to decorate like a Griswold.  You may want to consider some information that the US Department of Energy put together information about energy requirements of Christmas lighting.

According to the DOE, it can cost up to $10 to light a six-foot tree, 12 hours a day for 40 days using large C-9 incandescent lights while incandescent mini-lights would cost about $2.72.  LEDs on the other hand would cost 27 cents or 82 cents respectively to light that same tree for the same period of time.  Over a decade, it could be quite costly to stick with incandescents.  The DOE table is below.

Retailers are bringing more LED Christmas lights to consumers.  According to a recent article in the Kansas City Star newspaper, Walmart dedicated half of its shelf space to LEDs. Costs are coming down from $5 for a string of 50 mini LED lights, down from $6.30 last year.  In fact, Costco won’t sell incandescent Christmas lights in 2013.  General Electric, selling holiday lights since 1903, anticipates that two out of every five strings of lights sold this year will be LEDs.

So, it may be time to ditch the old fashioned Christmas lights for some new LEDs.  And for a laugh and some holiday cheer, watch Christmas Vacation or this clip from the movie where the Griswold’s incandescent Christmas lights take down the Chicago power grid.

US DOE Christmas Light Info

Estimated cost of electricity to light a six-foot tree for 12 hours a day for 40 days

Incandescent C-9 lights $10.00
LED C-9 lights $0.27
Incandescent Mini-lights $2.74
LED Mini-lights $0.82

 

Estimated cost* of buying and operating lights for 10 holiday seasons

Incandescent C-9 lights $122.19
LED C-9 lights $17.99
Incandescent Mini-lights $55.62
LED Mini-lights $33.29

*Assumes 50 C-9 bulbs and 200 mini-lights per tree, with electricity at $0.119 per kilowatt-hour (kWh) (AEO 2012 Residential Average). Prices of lights based on quoted prices for low volume purchases from major home improvement retailers. All costs have been discounted at an annual rate of 5.6%. Life span assumed to be three seasons (1,500 hours) for non-LED lights.

For Further Reading & Viewing

Kansas City Star, Christmas lights are going green, http://www.kansascity.com/2013/11/10/4612642/christmas-lights-are-going-green.html

Energy Manager Today, LEDs Lead the Way for Holiday Lights

http://www.energymanagertoday.com/leds-lead-the-way-for-holiday-lights-096959/

National Lampoon’s Christmas Vacation, Griswold Home Power Outage Clip: http://www.youtube.com/watch?v=inWKw8nqQlI

US DOE Info:  http://energy.gov/energysaver/articles/led-lighting

LEDs Making a Difference in Medicine

Special LED-based luminous ceiling lighting by Philips

Special LED-based luminous ceiling lighting by Philips

There have been quite a few stories lately about how LEDs are making a difference in medical settings. Here are a few cases where LEDs are making a difference with infection control, intensive care unit lighting and in medical research for brain disorders.

Controlling the spread of infection through mobile devices in hospitals

The statistics about hospital acquired infections (HAIs) are staggering.  According to the US Centers for Disease Control, HAIs inpact more than a million people a year in the US alone and are linked to nearly 100,000 US deaths per year.  More than 50 percent of healthcare workers admit to using mobile devices during direct physical contact with patents and yet only 8 percent say that actually clean them.  According to Hospital and Health Networks, 65 percent of doctors believe that the increased use in mobile devices in the healthcare environment leads to the spread of disease.

Sensor Electronic Technology, Inc. (SETi) plans to unveil a new line of disinfection cases for phones, tablet computers and other mobile devices at Medica tradefair in Dusseldorf, Germany, November 20 23, 2013. Using SETi’s UV LEDs, the disinfection cases are the world’s first fully portable disinfection units and are designed to be carried with the mobile device as a protective case as well as a disinfection system.

Using LED lighting to help critically ill patients

Special LED-based luminous ceiling lighting by Philips has been introduced into clinical use by the Charité Campus Virchow Clinic in Berlin as part of a unique stress-reducing concept called Parametric Spatial Design. Simulating energizing daylight to comfort critically ill patients, Parametric Spatial Design uses the area above a patient bed to create sky-like visuals mimicking daylight customized to the needs of individual patients.

Clinical research has shown that factors like loud noise, inappropriate lighting conditions and social isolation can increase the risk of patients in intensive care slipping into a shock-like state.

Philips played a significant role in designing this innovative concept.  The luminous ceiling from Philips combines a natural, dynamic rhythm of daylight and the effects of gentle colorful light and visual content to create a soothing environment for patents. It incorporates 15,400 LEDs and extends from the ceiling onto the wall in front of a patient’s bed, filling a patient’s field of vision.

Shining Light on Brain Disorders

Researchers at Washington University School of Medicine in St. Louis (WUSTL) are using tiny, electronic devices that include an LED to identify and map neural circuits in the brain especially those that target specific populations of brain cells that malfunction in depression, pain, addiction and other disorders.

The team’s work has been recognized with a rare grant called EUREKA (Exceptional, Unconventional Research Enabling Knowledge Acceleration) that funds high-risk/high-reward projects from the National Institutes of Health (NIH) which awards only 12 to 18 such grants each year.

The WUSTL team will develop specialized, optically sensitive G-protein-coupled receptors on brain cells that will make it possible to control cell signaling in the brain with light.  Combining these new receptor tools with the wireless micro-LED devices implanted in a mouse brain should enable researchers to learn about molecular and cellular events that underlie stress, addiction and depression.  The researchers hope to isolate and map the brain networks involved in stress by studying how the mice interact in their cages.

The team developed the special wireless micro-LED devices with researchers at the University of Illinois in Urbana-Champaign.  Many researchers use optogenetic techniques to isolate pathways in the mouse brain, but those animals are often tethered to wires.  The team at WUSTL can observe animals that are able to move freely because the LED devices that they developed are portable and wireless.

For Further Reading

LED Journal, Using UV LEDs to Control the Spread of Hospital Acquired Infections, http://www.ledjournal.com/main/markets/applications/using-uv-leds-to-control-the-spread-of-hospital-acquired-infections/

Philips News Release, Luminous ceiling from Philips simulates daylight to comfort critically ill patients in Intensive Care, http://www.newscenter.philips.com/main/standard/news/press/2013/20131024-Luminous-ceiling-from-Philips-simulates-daylight-to-comfort-critically-ill-patients-in-Intensive-Care.wpd#.UoPhB_mtmSo

Bioscience Technology, Tiny Devices Can Shine Light on Brain Disorders,  http://www.biosciencetechnology.com/news/2013/11/tiny-devices-can-shine-light-brain-disorders#.UoY5bhqtmSq

 

Food for Thought – Increasing Food Production with LED Lighting

Cary Mitchell, from left, and Celina Gomez harvest tomatoes grown around red and blue LED lights, which use far less energy than traditional high-pressure sodium lamps in greenhouses. (Purdue Agricultural Communication photo/Tom Campbell)

Cary Mitchell, from left, and Celina Gomez harvest tomatoes grown around red and blue LED lights, which use far less energy than traditional high-pressure sodium lamps in greenhouses. (Purdue Agricultural Communication photo/Tom Campbell)

We’ve touched upon innovative uses of LEDs and research into the benefits of LEDs with cows and bees, but there’s news that LED lighting can cost effectively improve the growth of greenhouse tomatoes and a start-up is working on affordable LED lighting to help small farms increase egg production in chickens.

According to the USDA, the U.S. is one of the world’s leading producers of tomatoes, second only to China. Fresh and processed tomatoes account for more than $2 billion annually.  Fresh-market tomatoes (not the ones that are processed) are produced in every state, with commercial-scale production in about 20 States led by California, Florida, Ohio, Virginia, Georgia, and Tennessee. The supply is seasonal depending on the weather.

Many producers grow tomatoes in greenhouses off-season, traditionally lit by very warm high-pressure sodium lamps. Researchers at Purdue University are looking into whether growing tomatoes under LED lights in the winter can significantly reduce greenhouse energy costs without sacrificing yield.

Perdue horticulture professor Cary Mitchell, interviewed in a Purdue newspaper, said the average tomato is shipped about 1,500 miles from warmer climates where they’re grown to cooler climates that cannot produce the fruit cost-effectively in the winter.  According to Mitchell, the journey is costly because tomatoes are picked green and ripen during shipping, decreasing quality and flavor. In addition, the shipping distance adds cost and adds to the industry’s carbon footprint.

Mitchell and doctoral student Celina Gómez experimented with light-emitting diodes, which are cooler and require far less energy than traditional high-pressure sodium lamps used in greenhouses. According to the article, the researchers received the same yield – size and number of fruit – with high-pressure sodium lamps and LED towers, but the LEDs used about 25 percent of the energy of traditional lamps.

The goal of the research is to reduce costs to the point where local growers could compete with the tomatoes that are shipped from far-away places. Local tomatoes could be harvested vine ripe, would taste better and would boost local economies.

“The United States still imports one-third of its tomatoes from Mexico and Canada, as well as other countries,” Mitchell said in an interview with Purdue Agriculture News. “This technology could allow U.S. growers to create local jobs that shrink carbon footprints and produce better-tasting tomatoes.”

Finally, a small group of recent grads from of the University of California, Davis, formed start-up Henlight to develop a solar powered LED light for small scale egg farmers to light chicken enclosures.  Scientific evidence shows that the amount of eggs a chicken will lay is strongly correlated to the amount of sunlight received per day.

Large-scale egg producers already use light to artificially boost egg production.  For example, the spring and summer typically provides between 12-16 hours of sunlight per day giving poultry the necessary amount of light to reproduce (produce eggs).  In the fall, the amount of daylight decreases along with egg production.  This reduces a farmer’s income and access to nutrition from eggs.   Henlight could bring this capability at low cost to small farms around the world .  Henlight’s founders received a $10,000 prize as start-up investment to launch the product.

For Further Reading

Clearlysapphire.com, Benefits of LED Lighting for Cows and Bees, http://blog.clearlysapphire.com/?p=472

NPR Berlin, Increasing Egg Production On Small Farms: A Solution To The International Food Crisis?, http://nprberlin.de/post/increasing-egg-production-small-farms-solution-international-food-crisis

Purdue University, Agriculture News, LEDs reduce costs for greenhouse tomato growers, study shows, http://www.purdue.edu/newsroom/releases/2013/Q2/leds-reduce-costs-for-greenhouse-tomato-growers,-study-shows.html