﻿A simple task like picking a light bulb can be very intimidating
because of all the options available to us. One thing’s for certain:
we’re told to switch the light bulbs in our homes from incandescents to energy
efficient LEDs. Many countries are phasing out and banning old incandescent bulbs. But what’s
the difference between the two? Should we still use incandescents in certain cases? What are the
downsides of using LEDs? We’re going to answer all those questions and more in this video.
Let’s start with how incandescent light bulbs work. The key component is a 6 foot long coiled
piece of tungsten metal. Tungsten has a very high melting point and high resistivity. Electricity
has a difficult time passing though. The tungsten atoms are heated up and electrons temporarily move
to higher energy levels. When the electrons move back to their original energy levels,
they release extra energy as photons or light. This phenomenon is called incandescence.
Two nickel-plated copper wires hold up the tungsten filament. These are connected to the
aluminum foot of the bulb and the screw threads. An inert gas like argon or krypton fills the
glass bulb. Ordinary air would rapidly oxidize the filament and the bulb would burn out in seconds.
The tungsten filament inside a light bulb can reach temperatures as high
as 4,500 degrees Fahrenheit or 2500 degrees Celsius. Over time, the tungsten evaporates
and is deposited on the inner surface of the bulb causing black spots. Incandescent bulbs
are very wasteful and inefficient because only 10% of the energy used generates light. The remaining
90% of the energy used generates heat. Light Emitting Diode or LED bulbs work
very differently. Their key component is a semiconducting material like gallium arsenide,
gallium phosphide and indium phosphide. They make up a diode that allows current to flow in only one
direction. The n-type material has extra electrons and is negatively charged. The p-type material
has electron deficient holes and is positively charged. Applying an electrical current to the
diode pushes the atoms in both materials toward the junction area. Electrons move from the n-type
material to the p-type material and release energy in the form of photons or light.
In addition to the diode or chip, LED bulbs consist of a driver that regulates the input
current, a heat sink that draws heat away from the chip, a socket or base and a lens made of
durable plastic. LED lights are cooler because they do not rely on heat to produce light. They
can reach temperatures of around 150F or 65C. LEDs are more energy-efficient because 40% of
the energy used generates light, the remaining 60% of energy used generates heat.
The heat generated from incandescent bulbs can be useful in certain instances. Heat lamps are
commonly found in restaurants to keep food warm. They can also provide heat and warmth to eggs and
pet animals like chicks, lizards, fish and snakes. They were used in Easy-Bake ovens to cook small
cakes. Wax warmers also use a small incandescent bulb. And, of course, lava lamps. Paraffin wax is
heated by an incandescent bulb. It becomes less dense and rises to the top of the mineral oil. It
then cools down, becomes heavier and sinks. Over the past 20 years, LEDs have replaced almost
every other type of bulb. They are used for TV backlighting and in smartphones. Solid state
LEDs are resistant to shock and vibration so they are used for flashlights, headlights
and construction work lights. They are also very versatile and can mimic neon lights, edison bulbs,
incandescent lights, CFLs and more. Now let’s compare the properties of
incandescent and LED light bulbs. Incandescent bulbs have a shorter lifespan of 1,500 hours
after which the tungsten element burns out. LEDs bulbs have a longer lifespan
of 30,000 hours. That being said, the market is flooded with cheap LEDs that do not last as long
as they claim they will. These LEDs that I bought off Amazon don’t last for more than 4 months
despite claims of a 30 year lifespan. Related to this is the concept of planned
obsolescence. Incandescent fixtures in the past had a separate base and bulb.
When the bulb burnt out, you could easily replace it and continue using the fixture.
Nowadays, ultra-thin recessed LED lights like this one are fully integrated. If it stops working,
you cannot simply replace a bulb. You’d have to turn off your breaker, disconnect the junction box
and replace the entire fixture. These types of lights are cheap, but not future-proof.
Before we move on I’d like to talk about the sponsor of this portion of the video,
Insulation4US. They are the largest US online retailer for insulation products.
They ship nationwide with over 800 locations in their huge distribution network. Insulation4US
is cheaper than big-box retailers and they offer a $60 flat shipping fee on 80% of all products.
Brands such as Owens Corning, Rockwool, Hunter Panels, Rmax, Kingspan, Handi-Foam Spray Foam,
Bubble Wrap and more are available online to purchase today and to be delivered directly
to your job site. Use Promo Code Belinda5 to receive an additional 5% discount off your next
order with Insulation4US.com. Back to comparing these 2 lights.
Incandescent bulbs work on both alternating current and direct current. LED bulbs have an
inbuilt circuitry that converts AC to DC. They will not work with DC current.
Incandescent bulbs are cheaper but they are almost impossible to find anymore.
LEDs are more expensive but you will save a lot of money over the lifetime of the bulb.
For example, a 100 watt incandescent bulb running for a full year would use 876 kWh of
energy, which would cost $130 in electricity. An equivalent 16 watt LED bulb would use only
140 kWh of energy and cost just $21 a year. Incandescent bulbs don’t have any electronics,
so they can be used inside ovens or hoods. LEDs cannot withstand high temperatures so they should
never be used in ovens. They can melt, release toxic fumes and cause health problems.
Incandescent bulbs can take a while to warm up to their full brightness. Most LED bulbs are ‘instant
on’ meaning that they will reach full brightness as soon as they are turned on. However, some
cheap LEDs are sensitive to current. A very small change will cause the light to flicker like these
reading lights I got off Amazon. It’s better to buy quality lights from reputable brands like CREE
or GE. They use eutectic soldering technology on the LED chips that eliminates the flickering.
All incandescent bulbs are dimmable. They can range from 100% all the way down to 0%.
Not all LEDs are dimmable. If you try to cut off a portion of the electricity, you will
strain the driver within your LEDs and decrease its lifespan. You should always make sure to get
a compatible switch for dimmable LEDs. Buzzing or humming is another common problem
of LED lighting. It is mainly due to vibration of the electronic components
inside the lamp. This usually occurs when trying to dim an incompatible LED bulb.
Incandescent bulbs are the purest artificial light source. Their spectrum is almost identical to
daylight. The measurement of how colors look when lit by a bulb is called color rendering index or
CRI. Incandescent bulbs have a CRI close to 100 or daylight. LED bulbs can vary drastically, from 80
to 98. Let’s take a look at the lighting inside my new Samsung fridge. This piece of ham looks
quite unappetizing because of the cool white light and lower CRI of the bulbs. It looks completely
different under a warmer, incandescent bulb. On a more fun note, certain LEDs use red,
green and blue lights to create a range of colors. You can switch them using a tiny microcontroller
in the bulb and control them with an app. If you want yellow, the bulb turns on red and green.
For cyan, it turns on green and blue. For white, it turns them all on.
Incandescent lights are omnidirectional, meaning they produce light in 360 degrees. This can be
inefficient for certain light fixtures like boob lights because half the light needs to be
reflected and redirected. LEDs, on the other hand, are one directional, so no light is wasted.
Let’s end this comparison by talking about blue light issues. There is a lot of ongoing research
into the side effects of using LEDS. They emit more blue light than incandescent bulbs, which are
more on the red end of the spectrum. Blue light can cause a disruption in your circadian rhythm
and negatively affect your ability to fall asleep. They can also trigger migraines,
cause eye fatigue, nausea and vision loss in extreme cases
So, in conclusion, good quality LED bulbs are more efficient than incandescent bulbs.
They can last longer, they’re cheaper in the long run and are very versatile. But,
we must be aware of color temperatures and how blue light can affect our mood and health.
Let me know if we should discuss warm versus cool light in another video.
Don’t forget to hit that subscribe button, notification bell and the like button too.
I’ll link my Patreon page in the description. If you can support me, I’d really appreciate it.
A big thank you to everyone already supporting me. Thanks for watching. See ya.