If you're new to commercial lighting, the concept of a ballast can be an odd one. When you're used to just screwing light bulbs into sockets and flipping switches, the transition to ballast-dependent lighting technology can be frustrating.
Let's back up. What exactly is a ballast? We explain that in detail in our appropriately-titled post, "What is a ballast?" But here's the gist, as we explain in that post:
A ballast is the functional heart of a fluorescent or HID light source. Just as a heart regulates blood flow to your body, a ballast ensures that a lamp stays lit by managing the distribution of energy throughout the fixture. Hearts work to distribute blood via channels, or arteries, in the body to keep a body active and alive. Ballasts do the same for the fluorescents and HIDs in your buildings, just with energy as the lifeblood.
Incandescents don't need ballasts. You can wire electricity right to their sockets, screw them in, and voila –– light. The same goes for LEDs, technically, except many LEDs are also made to work off of a ballast. For more on this, check out our article, "Plug and play vs. ballast bypass and other linear LED options."
LEDs use similar technology –– something called a driver –– but are not, by nature, ballast dependent.
Which lamp types are ballast dependent? Check out the table below.
|Incandescent||No incandescent bulbs require a ballast.|
|Halogen||No halogen bulbs require a ballast.|
|Fluorescent||All fluorescent bulbs require a ballast.|
|Compact fluorescent||All compact fluorescent (CFL) bulbs require a ballast, which is often integrated.|
|HID||All HID bulbs require a ballast, which is sometimes integrated.|
|LED|| No LED bulbs
When it comes to LEDs working with a ballast, in particular, there can be a lot of confusion.
One line of thinking out there is: If an LED doesn't require a ballast, why would anyone want to mess with an additional component? And that's a fair question.
The reality is that if the existing fixture includes a ballast, the swiftest, easiest way to retrofit to LED would be to buy a plug-and-play lamp and continue to run it off the ballast. Additionally, using a plug-and-play LED that works with the existing ballast means that you aren't making any fixture modifications, resulting in lower installation costs and a potentially easier time dealing with strict building codes like Title 24 in California. That said, there are still other priorities to consider.
Plug-and-play, line voltage, hybrid, or remote driver LED?
The question of whether or not to use a ballast-compatible LED really comes down to three factors: project type, budget, and maintenance. Let's tackle them one by one.
1. Project type
Retrofit: If you're retrofitting an existing space, the easiest and safest option is a plug-and-play LED. It amounts to a simple lamp swap. You don't have to mess with removing a ballast, though you may have to replace it down the road. Another option that is becoming more common –– especially with linear LEDs –– is a "hybrid" LED that will work with the ballast until the ballast fails and then can be direct-wired to line voltage from then on. There are still safety reservations with these hybrid products, so our top recommendation at this point is the plug-and-play version. Finally, there are some retrofit projects, like replacing HID garage fixtures or wall packs, where replacing the entire fixture may work out best for you.
New construction or complete remodel: If you're doing a complete remodel or tackling a new building project, you may want to consider a remote driver LED since you'll get the benefit of the highest-rated efficiency and longest life with a minimal cost premium. Another serious consideration in these projects is an integrated LED fixture.
Minimal Up-front Cost: When you're looking for the lowest up-front cost on an LED retrofit, the installation labor can represent a significant portion of your overall project cost. With this in mind, the plug-and-play LED products that work with an existing ballast are the top choice.
Best Long-Term Savings: A priority on long-term savings requires you to consider energy costs and on-going maintenance. There are a few options to consider if this is your goal:
- Ballast bypass. The ballast-bypass option carries two significant benefits. First, you won't have to worry about replacing a failed ballast down the road. Second, your LED wattage will not be affected by the ballast factor, which could result in slightly better energy savings. Still, a ballast-bypass solution isn't typically our top recommendation.
- Plug-and-play with a new ballast. Plug-and-play products are the safest, and when you pair them with a new ballast, you won't have to worry about any maintenance for a while. With that said, that's a similar amount of work and cost to our next option.
- Remove driver. With a remove
driveryou get the maximum LED efficiency paired with a long life rating. If you are motivated by maximum savings over the long-haul, this might be your best option.
- New fixture. In certain applications, like parking garage fixtures or exterior lighting
inparticular, your best option for maximizing long-term savings may be a new LED fixture. Don't count this one out too soon.
Easiest long-term maintenance: Lighting maintenance can be a pain, especially if you need expensive lifts or you have to be a contortionist to get access to the fixture. For this reason, the life rating of the LED should be one of your top considerations. Since a remote driver gives long-life ratings and removes the question of the ballast failing, this or a new LED fixture is probably your best bet.
With any option you choose, it's important to consider a 360-degree view of your potential savings from a lighting retrofit. You can download a free copy of our e-book on energy savings calculations to get simple, step-by-step explanations and a solid payback estimate.