Small changes in your home can add up big savings over time in electricity, trash, and cash. One of the easiest swaps to make is replacing your old light bulbs with LEDs—if you haven’t already. In 2015, just 4% of U.S. households only or mostly used LED bulbs, but by 2020, that number was up to 47%, and experts expect it to keep climbing.1,2 That’s good news for the climate, because lighting is one of a home’s biggest electricity hogs, which means switching to less-power-hungry options can greatly reduce planet-warming impacts. In 2017, for example, swapping old incandescent for LEDs avoided more than 500 million tons of carbon dioxide emissions, equivalent to shutting down 162 coal-fired power plants.3
In case you haven’t yet ditched those old Edisons, this is your cheat sheet for understanding why LEDs are preferable over other bulbs in terms of cost, efficiency, and longevity.
Comparing LED vs. CFL vs. incandescent lights
There are three main types of light bulbs. The first is the incandescent light bulb, which Thomas Edison famously invented in 1879. Electric current flows through a metal filament in this bulb, heating it until it glows and produces light. As of August 2023, the Energy Independence and Security Act prohibits U.S. stores from selling most incandescent light bulbs because of how much power they draw.4
The second type of light bulb is the light-emitting diode (LED). This bulb was invented in 1962, and mass production began six years later. In an LED, electrical current passes through a semiconductor microchip to produce light.
Next came the compact fluorescent light (CFL) in 1976. In this light, electric current runs through a tube containing argon and mercury vapor, which react to create ultraviolet light. This non-visible light excites a fluorescent coating on the inside of the tube, making it emit a visible glow.
Differences in efficiency
The varying ways these three lighting types produce their glow means that they have different efficiencies, which is a measure of how much energy they lose as heat. Incandescent bulbs lose 90% of their energy as heat, which means they’re the least efficient overall. CFLs aren’t much better, as they lose about 80% of their energy as heat. LEDs, meanwhile, lose a maximum of 20% of their energy as heat. Because of this, they also require less voltage to create the same amount of light as other offerings, and switching them on and off frequently does not affect the light they give off.
Efficiency is generally expressed in lumens per watt (LPW). The higher the number, the more efficient a light source is. CFL bulbs, for example, need slightly more energy input to produce light during the first 30 seconds to three minutes after turning on. They’re less efficient during this period. Afterwards, efficiency varies between different CFL bulbs, just as it does between LED bulbs.
DIfferences in lifespan
An LED can last for more than 50,000 hours—30 times longer than an incandescent light bulb and three to five times longer than a CFL light bulb. In the time you use one LED, you can spare 30 incandescent bulbs from being produced, shipped, and trashed.
Additionally, LEDs don’t burn out and die the way CFLs and incandescents do, because the microchip in LEDs never stops working entirely; it only dims. Because of this difference, an LED’s lifespan is an estimate of how long it will take for light output to decrease by 30%—rather than when it will go totally dead.
Differences in cost
LEDs are generally more expensive than CFL and incandescent bulbs upfront. But because they need to be replaced less frequently and use less electricity, they’re the clear winner for savings in the long run. Considering the average amount of lightbulbs in the American home, average time of use, and the average cost of electricity across the U.S., using LEDs will cost around $65 a year. This is a bargain compared to the yearly total of $394.20 for incandescents and $98.55 for CFLs.
Differences in chemistry & toxicity
CFL light bulbs contain small amounts of toxic chemicals like mercury, which can damage ecosystems, particularly by causing nervous system damage in wild animals high on the food chain. LEDs, on the other hand, use a microchip to produce electricity. They are also recyclable: You can dump your old LEDs at most home improvement stores, and some localities accept them in curbside recycling bins. Earth911 maintains a good resource for figuring out where to take spent LEDs.
More simple upgrades to up your energy efficiency
Switching out your lightbulbs is one of the easiest ways to lower your electricity consumption without breaking the bank—but it’s far from the only option. Here’s another handful of simple yet impactful ways to make a difference.
How to make your laundry routine more efficient
Doing a load of laundry can be an energy drain, but it’s super straightforward to slim that impact down. Washing your clothes on cold water settings takes energy needed to heat up water out of the equation, and air drying your duds means you can skip the use of a dryer all together. Here’s what you need to know about upping the efficiency of your laundry routine.
How to stay cool without blasting the AC
Keeping our homes at liveable temperatures in the most scorching of summers can mean a shocking electricity bill. Luckily, there’s a lot we can do to stay cool without cranking up the AC, like using shades to block out the sun, creating a cross breeze, taking advantage of ceiling and floor fans, and planning appliance use according to the rise and fall of temperatures throughout the day.
Upgrades for renters
While you might not get to make giant energy efficiency improvements on your rental, there’s still work folks can do even when they don’t own their home. Some easy tips include hooking up smart power strips, sealing up gaps that allow air to escape, installing cellular blinds, and utilizing a smart thermostat.
- Residential Energy Consumption Survey (RECS), U.S. Energy Information Administration ↩︎
- LED Penetration Rate of the Global Lighting Market Based on Sales from 2012 to 2030, Statista, Jan. 2021 ↩︎
- Update on the Status of LED-Lighting World Market Since 2018, European Commission, 2021 ↩︎
- S.1399 – Building American Energy Security Act of 2023, 118th Congress (2023-2024), May 2023 ↩︎