At Timberpeg, we are proud of how energy efficient our homes are and have talked about this topic several times on this blog. While having a tight thermal envelope is important to reduce heating and cooling costs, lighting is also a very large consideration for a home’s energy consumption. In most homes, twenty to fifty percent of all electricity consumption is due to lighting. Although incandescent lights are simple, cheap, and provide a light quality that many find pleasing, they are notoriously inefficient as light sources. In this post, we’ll talk about how great strides in light-emitting diodes (LEDs) have made them a great solution for energy efficient lighting.
Incandescent lights date to before the proliferation of mains electricity, and they have not changed much in the previous century. Electricity flows through a tungsten filament, which becomes very hot and glows. This process is not very efficient as a light source, however, since around 95% of the light bulb’s energy is consumed as heat. The Energy Independence and Security Act of 2007 set efficiency standards for lighting that are higher than incandescent bulbs can reach. This law is reaching full implementation this year, and as a result it is illegal to import or manufacture incandescent bulbs in the 40 to 150 Watt range. Some options for replacing these bulbs include slightly more efficient halogen bulbs or compact florescent bulbs (CFLs).
While CFLs are a fine choice for efficient lighting, recent strides in LEDs make them very attractive as a light source. A 60W equivalent LED bulb will only use around 10W of power, making it more efficient than even the 13W an equivalent CFL will draw. This means that a LED bulb used 3 hours a day will save a homeowner around $6 a year in electricity costs compared to an incandescent bulb, assuming 11 cents per kilowatt-hour electric rates. Thus, although a LED bulb like these costs about $10, you will recuperate the cost of the bulb within a year and a half (and, yes, they will last far longer than that. Read below.) If your electricity costs over 18 cents per kilowatt-hour, you will pay off the bulb in under a year.
An LED will continue to save you money as time goes on, since they have remarkably long lifespans. Unlike incandescent bulbs which only last around 1,000 hours of use (about a year), LED bulbs have typical lifespans in excess of 25,000 hours. Thus, assuming the same 3 hour per-day usage, an LED bulb has a lifetime approaching 25 years. Furthermore, LEDs are solid state devices and thus rarely break, so their lifetime is defined as the time when the light output falls to 70% of its original value. You could very well find yourself a quarter century from now with a still very functional LED light! Although LEDs are now very practical for 60W-equivalent bulbs, higher output lights are not as efficient. The 120W-equivalent LEDs are no more efficient than CFLs, and higher output LEDs are not economically feasible. Also, the high upfront cost is a deterrent to many people. Despite these concerns, the future of LEDs looks bright indeed. Many appreciate the fact that LEDs lack the mercury present in CFLs. Also, the efficiency of LEDs has increased 20-fold and the price has dropped 10-fold in the past decade, and this trend looks to continue in the future, making LEDs an increasingly attractive lighting option. Are you ready to build an energy-efficient barn home or timber frame home of your own? If so, Timberpeg is the right place to start. Contact them today to get started on the design for your new home, and you'll be picking out the lighting choices soon.