The Light Direction Blog:
Retro or Retrofit: Do I keep replacing my H.I.D. lamps or retrofit to LED? by Frank Grobmeier
Everything that was once loved is cool again! It seems like everything comes back in style if you give it enough time. Well, that may apply to fashion, but it doesn’t apply to many legacy lighting technologies like H.I.D. lamps and fixtures. Once those big shoebox fixtures in the sky are gone, they won’t be coming back. So, when is the right time to make the move to LED? Am I too late to retrofit? And do I transition to LED retrofit kits or switch to brand new LED fixtures? We’ll examine these questions and break down the three types of systems (H.I.D. ; LED Retrofits: New LED Fixtures) , explore the pros and cons of each in this blog.
Generally, existing H.I.D. systems are either metal halide or High Pressure Sodium, although other existing H.I.D. systems could be low pressure sodium or mercury vapor. These systems are usually found either in outdoor applications such as parking lots and street lighting or in highbay applications such as warehouses or big box retailers.
LED Retrofit kits typically consist of an LED module and driver that replace the existing lamp and ballast. However, there are some direct replacement LED bulbs that operate on the existing ballasts and fit in the existing sockets.
New LED fixtures are fully integrated fixtures that replace the whole existing H.I.D. fixture housing.
Let’s start by talking about H.I.D. lamps and fixtures. If your business is still using metal halide or high pressure sodium lamps, you would be considered a “laggard” in terms of the technology adoption life cycle, but don’t take that as a negative. There are plenty of good reasons that people tend to wait until the last stage of the technology cycle. The main reason is cost. While LED fixtures that replace H.I.D. fixtures have been around for a long time, you might be saying, “why would I spend a great deal of money to replace a fixture that is still working, and the replacement lamps and ballasts are still available?”
COSTS
If you have an existing H.I.D. lighting system, upgrading to a new LED system or retrofit would most likely result in some upfront costs or require financing. So, staying with your existing system and replacing lamps and ballasts as they fail may be a good option for you.
LED lighting has relatively high initial costs, but the system does have very low lifetime costs. The technology pays back the investment over time (the payback period). The major payback comes primarily from reduced maintenance costs over (dependent on your labor costs) and secondarily from energy efficiency improvements (dependent on your electricity costs).
H.I.D. is relatively cheap to purchase, but it is fairly expensive to maintain. H.I.D. bulbs will likely need to be purchased several times over the life of the system, and the associated labor costs will have to be paid in order to achieve the equivalent lifespan of a single LED light.
Upfront Costs: The cost of replacing H.I.D. lamps and ballasts is low compared to replacing that existing fixture with a new LED fixture or retrofit kit. This perceived high cost of LED lighting is the main reason people continue to use these older technologies, only replacing the lamps and ballasts when they burn out. Keep in mind though that most utility companies offer some type of rebate program or financial incentives to get users to switch from H.I.D. fixtures to LED fixtures. These incentives help reduce the initial costs for the conversion to LED.
Maintenance Costs: Labor costs to maintain an H.I.D. system is significantly higher than that of an LED system. Lamp and ballast changes on an H.I.D. system occur every one or two years, depending on use. LED systems can last 10 or more years depending on use and require little to no maintenance over that time period.
Lifetime Costs: The lifetime cost of a lighting system factors into the initial cost of the system: the installation cost and the lifetime maintenance costs, including the replacement materials such as lamps and ballasts, plus the energy cost to operate the system. When comparing an H.I.D. system to an LED system, the LED system generally wins every time due in part to the high cost of labor to replace the materials and the high energy costs to operate the technology.
Another consideration is the efficiency of the three types of systems, along with their associated life spans.
EFFICIENCY AND LIFE
LED fixtures are very energy efficient and last longer than almost every lighting type on the market. H.I.D.s are particularly efficient compared to other types of systems (i.e. CFL and incandescent); however, they lose out to LEDs for three principal reasons: H.I.D. lamps have a dramatic light output drop over time; their system efficiency is much lower due to all of the losses associated with omnidirectional light output; and the light needs to be redirected to a desired area.
Energy Efficiency: LED fixtures tend to be about 70-80% more efficient than H.I.D.s.
Lumen Depreciation (Light Loss): H.I.D. lamps have a rapidly accelerating light loss and color shift. Soon after the initial installation of the lamps the H.I.D.s quickly start to dim. For example, in the first year, a metal halide lamp can lose up to 50% of its light output. LEDs on the other hand generally maintain 70% of their light output over their 5-10 years of use.
Directionality / System Efficiency: LEDs direct their light forward and often use optics to control the beam / directionality of the light. This ensures a high system efficiency where the light reaches the source. H.I.D. is omnidirectional meaning it emits light for 360 degrees. This causes light to stray and get trapped inside the fixture, reducing the system efficiency.
Life: The average rated life of an H.I.D. lamp is between 1 to 2 years of operation and tends to fail by flickering and cycling—ultimate becoming too dim to be useful. Because of this, H.I.D. lamps are typically only warrantied for 90 days to 1 year, depending on the lamp. LED fixtures on the other hand last between 5-10 years and come with a minimum 5-year warranty.
PERFORMANCE
The performance factors of a lighting fixture are most critical to the safety, aesthetics and human experience of the application. It’s where the art and science of lighting intersect. LED fixtures, by the nature of their technology, allow for the control of color temperature, vibration, shock and eliminate the warmup time and flickering often associated with H.I.D. systems.
Warm Up Time / Cycling / Flickering: LEDs are instant on and produce consistent light without issues with flickering or cycling. H.I.D. lights require a noticeable warm up period that can last up to several minutes. They may also flicker or cycle on and off as the bulb reaches the end of its useful life.
Color Temperature: H.I.D. lamp color temperatures are determined by the materials used to generate the light. High Pressure Sodium, Metal Halide, and Mercury Vapor all utilize different chemical compositions to generate light and have specific color temperatures associated with the chemical composition in their bulb. LEDs come in a range of different color temperatures so you can select the best light color temp for the application.
Operating Temperatures: Both LEDs and H.I.D.s will operate in high and low temperatures, but in this range of temps, the LEDs will turn instantly while H.I.D.s will need time to warm up to reach their full output.
Shock & Vibration: LEDs are solid state devices built with electrical surge protectors that are robust and able to withstand significant vibrations and electrical shocks. H.I.D.s are relatively fragile. Perhaps most importantly, H.I.D. lamps require special handling and disposal due to hazardous materials, like mercury, that they contain.
So, in conclusion let’s examine the pros and cons of each of these systems:
PROS & CONS of Each Technology:
H.I.D. Lamps and Ballasts (GOOD OPTION):
Pros: Low initial costs; Decades of reliability; Initial lumens on new lamps are very efficient.
Cons: Short life (only 1-2 years); Rapid light loss; High maintenance and lifetime costs; Significant warm up time; Poor color rendering and limited color temperatures; Prone to flickering and cycling; Omni-directional light means footcandles are dependent on system and reflectors. High UV output means yellowing and fading. Along with safety risks. Limited warranty. Contains mercury and requires special handling and disposal.
LED Retrofit Kit (BETTER OPTION):
Pros: Good life (5 years); Easy to install: Stable light over lifetime; No maintenance over life; Low lifetime costs; Instant on - no warmup time – no flickering – no cycling; Good color rendering; Several color temperature options; Directional light unlike H.I.D. lamps and corn cob replacements; No UV output means no yellowing and fading; Good warranty (5 Year Limited Warranty). Doesn’t contain mercury and requires no special handling or disposal.
Cons: Doesn’t fit all fixtures; Higher initial cost than H.I.D. lamps and ballasts; Doesn’t change the physical appearance or condition of the old H.I.D. fixture.
NATURALED LED Fixtures (BEST OPTION):
Pros: Long life (5-10 years); Upgraded modern look; Stable light over lifetime; No maintenance over life; Low lifetime costs; Instant on - no warmup time – no flickering – no cycling; Good color rendering; Several color temperature options; Directional light unlike H.I.D. lamps and corn cob replacements; No UV output means no yellowing and fading; Good warranty (5 Year Limited Warranty). Doesn’t contain mercury and requires no special handling or disposal.
Cons: Higher initial cost than H.I.D. lamps and ballasts; Requires skilled labor to install.
If you still have metal halide or HPS fixtures, all is not lost. Naturaled / Plusrite still offers a full range of replacement lamps and ballasts and will for the foreseeable future. Now might be a good time, however, to consider an upgrade. The Naturaled team is well versed on the financial incentives and rebates that could be available to help you finance an upgrade to either an LED retrofit kit or new LED fixtures.
Frank Grobmeier has over 30 years of product management and marketing experience with lighting manufacturers including decades in general lighting and specialty lighting with traditional and LED sources. He currently serves as on the Fanlight / Naturaled marketing management team and resides in the Chicago area.