Lights- Color Temperature and Color Rendering Index

Lighting is more than just replacing a lamp or ballast, it also has to do with color.  We have just helped Sterling Graphics with a move into a new space.  The kelvin temperature and CRI of the lamps they use are very important for their graphics business as they must have exact color matching ability. 

The kelvin temperature is often referred to as the color appearance of the light source – is it cool and crisp or warm and cozy?  This is a number system that ranges from 2700-6500.  CRI or color rendering index is the ability of the light source to reflect back to the eye the colors we expect to see in an object, this is ranked on a scale of 0 to 100.  Clear daylight is considered as a reference point of 100.

Some of the other businesses that we have helped that require accurate attention to these 2 factors are Dentists, auto body repair shops, craft and paint stores.  Lighting matters!

Incandescent, CFL or LED

This is the question you face when you need to purchase new lighting.  I will show you a comparison for a 60 Watt A19 – a standard light bulb for residential usage.

The incandescent bulb costs roughly $1.50 will last at 8 hours a day for 3-4 months.  Electricity cost per year is about $16.00.  This bulb is very hot to touch as most of the energy that is required to operate this bulb (60 watts an hour) is converted to heat.

A CFL equivalent costs from $2.50 - $4.00, and at 8 hours a day will last 2-4 years. Electricity cost per year is about $3.25.   Drawbacks for the CFL is that it contains mercury, has a slow warm up- is not an instant on, most are not dimmable and it is not intended to be turned on and off frequently as this will shorten it’s life.

The LED replacement costs about $7.00, are rated for 10-20 years of use at 8 hours a day.  Electricity cost is about $2.75 a year.  The LED bulb cost more upfront and not all are dimmable and excessive heat will shorten the life of the LED.  LEDs like cooler temperatures so consider this when you are choosing to go with the LED.

There is no perfect light bulb, you need to consider how you will be using the bulb (do you want it to dim, is it in a high heat area, how long it will be on at a given time) and what your budget is for purchasing and for annual utility costs.

This was part of a presentation I gave to #springChicks, #ChicksConnect, #Mastermind, #LED, #CFL, #EnergySavings in May 2015.

LEDs Shining Bright But Can You Dim Them?

With all of the excitement and amazing options and energy savings available with LEDs there may be a downside, the ability to dim them.  There are many reasons people like dimming their lights, ambiance, a warmer light and energy savings.  With most LEDs when dimmed they do not change to a warmer color (there are new ones coming out that will be able to change), also incandescents when dimmed drop about 24% or more in light output, LEDs light output diminishes 10% or less.  For both light sources there is an increased life when dimmed although with the extended life of LEDs this is not an important factor. Be aware that LEDs may not work with your current dimmer, it is recommended that you replace your dimmer when switching to LEDs and be sure that it is compatible with the LED you are choosing to install.