Light Bulbs: The Ultimate Home Guide

What Are Incandescent Light Bulbs?

Incandescent bulbs have been the most common type of lighting in homes since electricity was invented. They function through conducting electrical current along a filament made of tungsten metal. This filament heats up to around 2,300 degrees Celsius to glow and emit a hot (yellow) light. In terms of efficiency, this type of bulb produces a lot of heat. Still, it can only transform an average of 10 percent of the electricity used into visible light, making them the most energy-efficient lighting option.

While these light bulbs are much cheaper upfront than other options, they also can heat a home during the hot summer months. Since January 2014, incandescent bulbs are no longer manufactured in the United States, making them harder to find and purchase at retail stores.

What Are CFL Light Bulbs

CFL stands for compact fluorescent lamp. These bulbs are made from glass tubes filled with gas and mercury and function through the mercury molecules, becoming agitated as electricity moves through the two electrodes at the bulb's base. Mercury emits ultraviolet light that is invisible to the human eye, though the white coating inside the CFL bulb makes this light visible to the human eye.

These lights are much more energy-efficient than their incandescent counterparts and do not emit heat inside the home. While mercury exposure can cause several dangerous health effects, the amount of mercury in each CLF bulb is about 100 times less than old-time thermometers.

What Are LED Light Bulbs?

LED stand for light-emitting diodes and function as a two-lead semiconductor light source. When an electrical current is applied to the leads, electrons reconnect with the electron holes inside the device and release light in the form of photons. LED is the most energy-efficient form of lighting on the market today through the individual bulbs do cost more upfront.

Why Should You Use LED Lights?

While most homeowners around the country would welcome a 93% reduction in their yearly energy bills, not every family will have roughly $13,000 to finance a 6 kW residential rooftop solar system. However, almost every family can afford to pay an extra dollar or two for more energy-efficient light bulbs that will pay for themselves within months.

What Is the Cheapest Light Bulb to Use?

The average price of an incandescent light bulb is around $1.00. Your light bulb will use 60W of energy for that dollar and should last for an average of 1,100 hours. In comparison, the average CFL light bulb costs $3.00, lasts 8,000 hours, and will pull 15W of energy when turned on. LEDs, the most energy-efficient option on the market today, might cost you around $5.00 per bulb, but only use an average of 10W of energy while having an expected lifetime of 15,000 hours.

Simple math should show us that LEDs are the most economical choice. For 15,000 hours of light in your home, you would only need one LED bulb ($5.00), two CFL bulbs ($6.00), but 14 incandescent bulbs ($14.00). In terms of electricity cost, 15,000 hours of use at an average of $0.10 per kWh would cost you $15.75 for a LED bulb, $22.50 for two CFL bulbs, and an outrageous $90.00 for those 14 incandescent bulbs.

Since the average home in the United States has 45 light bulbs, homeowners could save around $3,300 on their energy bills over the 15,000 hours of use that is the typical lifespan of LED bulbs. Unfortunately, the EIA reports that only 1 percent of all homes use all LED lighting fixtures, while 71 percent of homes use no bulbs of this type.

What Is the Most Environmentally Friendly Light Bulb?

LED light bulbs require up to 90 percent less energy than incandescent bulbs, while CFL fixtures use 75 percent less. While LEDs and CFLs use much less energy, they also emit the same amount of light as measured by lumens, or the total amount of visible light to the human eye. Since LED and CFL light bulbs will also last much longer, this also means that fewer light bulbs will end up in the trash. CFL lights, however, contain between 3.5 to 15 milligrams of mercury, which is a potent environmental toxin that can end up in landfills when bulbs are disposed of incorrectly. LED light bulbs do not contain mercury and, as mentioned above, will last much longer than their incandescent competitors.

If every household in the US replaced just one incandescent with an LED light, we could collectively save enough energy to light 3 million homes for a year while preventing upwards of 9 billion pounds of greenhouse gas emissions each year. Each LED light bulb can prevent an estimated 450 pounds of greenhouse gas emissions over its lifetime, equivalent to 200 pounds of coal burned in a power plant.