Electrical 101: All About Those Lights

Our Virtual Lunch & Learn blog series explores a specific topic adapted from our most popular Allen & Shariff Lunch and Learn courses.

According to the U.S. Energy Information Administration, lighting accounts for 11% of all commercial electricity used in the United States. Becoming familiar with different lighting sources, criteria, and controls is not only important in creating the most comfortable interior environment for occupants, but also in reducing electricity usage and costs. Here are some of the key lighting takeaways from our Electrical 101 Lunch & Learn.

Lighting Sources – Knowing the features of available lighting sources means making the best decision for the space being built.

  • LED –  With green building and changing energy codes, LED fixtures are more prevalent now than ever. These fixtures are affordable and last up to 50,000 hours.
  • Fluorescent/Compact Fluorescent (FL/CFL) – Though some wattages are still manufactured, many lights of this type are regulated by the Department of Energy. T8 lamps are highly regulated, though T5 and T5HO are still widely used. CFL lighting is short-lived–though technically able to last for 10,000 hours, it generally begins to flicker after only 4,000.
  • HID Several lamp types fall into this category, and all have limitations. Metal halide lamps have a lifesapan of only 15-20,000 hours and 30% lumen depreciation. HPS is a slightly better choice, lasting 25,000 hours with only 10% lumen depreciation. Low pressure sodium renders color poorly and thus has a very limited application. For all HID lamps, the starting time is so long that they cannot be used as emergency lighting sources.
  • Incandescent/Halogen – This lighting source is being completely phased out due to high energy consumption, and is most commonly replaced with LED.
  • Induction – By far the greenest lighting source, induction lamps use a hybrid fluorescent technology, last for  100,000 hours, and the have the lowest lumen depreciation of any other lamp source. They don’t flicker or glare, and they have no electrodes like HID or FL/CFL. There are some limitations – wattage stops at 200w, they are not a source for emergency lighting, and they are somewhat expensive when compared with CFL.


Lamp Criteria –
Learn how to describe lighting in terms of temperature and color.

  • Color Correlated Temperature (CCT) is measured in degrees of Kelvin (K) on a scale from 1,000K to 10,000K and indicates how “warm” or “cool” a light source appears.  The low end provides warm, reddish light, while the high end provides cool, blue-white light that mimics daylight.
  • Color Rendering Index (CRI) is measured on a scale from 0-100 and refers to how accurately a light source renders color.  The higher the CRI value, the better a given light source’s rendering. Values of 90 CRI and greater provide the most accurate color representation.

Lighting Controls – Automatic Lighting Controls are required for most spaces. Individual manual controls and the ability to manually override automatic controls are also required. Exceptions include areas where safety or security are issues, such as exam rooms and service areas.

Types of automatic controls include:

  • Occupancy sensors
  • Vacancy sensors
  • Time systems
  • Daylighting sensors

Want to learn more about lighting and how it fits into an overall electric design plan? Contact Allen & Shariff to schedule an in-person presentation by one of our industry experts.

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