While shopping at a local retail store, I noticed that incandescent light bulbs were still for sale, and I watched customers picking them up to compare their purchase cost to that of LED bulbs. I wondered if they understood that the LED bulbs might cost a few cents more to purchase, but their lifetime time costs would be much lower.
As of January 2014, a law took effect that requires general use light bulbs to be at least 30% more efficient than the incandescent light bulbs in use at that time. In 2020, this law will require bulbs to be 60 to 70% more efficient. In response, incandescent manufacturers met the law’s requirements by creating a 43-watt halogen-incandescent bulb that produces only slightly less light than its 60-watt predecessor. However, a 60-watt equivalent LED only uses nine watts, and it will use less energy and last much longer than even a yet-more-vastly-improved incandescent bulb that meets the 2020 regulatory standard. Thus, despite the recently increased efficiency of incandescent bulbs, it is still well worth it, financially, to purchase the LEDs. Although the purchase prices are close, the operational costs are vastly different. A LED will provide 80% of its energy use as light and 20% as heat. A halogen-incandescent bulb provides the opposite, 20% light and 80% heat. Additionally, LED’s will last 10,000-20,000 hours versus only 3,600 for the halogen-incandescents.
Over time, the differences in efficiency lead to shocking differences in cost. In fact, if your 43-watt halogen-incandescent light bulb is on for four hours per day, you will burn through $75 more electricity over a nine-year period than if you had decided to switch to an LED. As a halogen-incandescent bulb only lasts around 2 ½ years, you will also be buying many more bulbs over the life of the single LED bulb. If the added cost of these bulbs is added to their higher operating costs, the total added cost is around $82. Penny wise but dollar foolish is an aptly applied saying!
Multiply savings of up to $9 per year by the number of light bulbs in your house! One Ammonoosuc Regional Energy Team (ARET) member added up the light bulbs in his house and came up with 100. He estimated that the average light was on for close to an hour per day, so that annual savings of $200 would be achieved following a complete conversion from incandescent bulbs to LEDs.
A 2015 Residential Energy Consumption Survey conducted by the U.S. Energy Information Administration indicates that most people understand the savings possible by replacing incandescent bulbs with LEDs or CFLs (compact fluorescent lights). CFLs are much more efficient than incandescent bulbs, but not quite as efficient as the more recently available LEDs. The study indicated that only 11% of households had all incandescent lights, 18% had no incandescent lights, and 71% had at least some LEDs or CFLs. These figures indicate to me that everyone was doing as I was doing. When incandescent bulbs burned out some years ago, we replaced them with CFLs. Now, years later, when the CFLs burn out, we are replacing them with LED bulbs.
Then, one day I wondered what it was costing me to keep those CFLs around. Perhaps it would make sense to replace them all right away. So, I did the math. CFLs are similar in cost and expected life to LEDs; 72% of their energy consumption goes towards light, and they will last around 10,000 hours. However, the CFL uses fifteen watts versus nine watts for the LED. A CFL light that is on for five hours a day will use more than 27 kWh of electricity (5 hours per day x 365 days per year x 15 watts = 27.4 kWh) and cost $4.65 annually, assuming electricity costs 18 cents per kilowatt-hour. A nine-watt LED would cost only $2.79 and the savings of $1.86 per year would be more than the cost of an LED bulb. Thus, it is not only worthwhile to replace incandescent bulbs with LEDs, it is also worthwhile to replace CFLs.
Suppose a household replaces five 60-watt incandescent bulbs that are on for one hour per day, ten CFL bulbs that are on for three hours per day, and ten CFLs that are on five hours per day. It will cost approximately $38 to purchase the 25 bulbs, but they will save nearly $50 per year or $600 over the life of those bulbs. This modest investment would provide a return far greater than best annual returns from the stock market.
On a larger scale, if NH’s more than 500,000 homes made similar upgrades to LEDs, they would together save about $24 million per year, which would lead to an annual increase in economic activity of $40 million as these saved dollars turned over from one NH business to another.
Mark Koprowski lives in Bethlehem, NH. He is a member of the board of the all-volunteer, non-profit Ammonoosuc Regional Energy Team (ARET), which encourages and supports economically and environmentally sensible energy practices in the Ammonoosuc Region of Northern New Hampshire. For more information about ARET and local energy solutions, go to www.ammenergy.org.