The Light and Dark Sides of LED Light Towers
Consider both sides of the equation when deciding between lighting towers equipped with LED and halogen lamps.
With fuel savings, lower cost of ownership and other benefits, it's no surprise that LED light towers are gaining more acceptance in the construction industry. In fact, most manufacturers now offer LED fixtures as a factory-fitted or aftermarket option. This does not mean that LED (light emitting diodes) will override halogen bulbs overnight. However, the lighting tower market is moving in this direction. How quickly it gets there depends on several factors that narrow the gap between LED's cost and its many benefits.
Lower Fuel and Operating Costs
The construction industry is well positioned to take advantage of LED lighting. Deree Bivins, product manager for Doosan Portable Power, puts fuel cost savings and cost of ownership at the top of their list of reasons. “Lighting towers with LED fixtures are much more fuel efficient than those with halogen bulbs, using 50% less diesel fuel,” he says. "LED fixtures also last several times longer than halogen bulbs." he adds.
With four lighting towers that can be equipped with LED luminaires, Doosan has recently released an interactive cost savings calculator to help potential users understand this point well. The calculator compares LED and halogen, takes into account the cost of diesel fuel and the shift run time for the light tower multiplied by the number of shifts per month.
The first example with the calculator shows diesel delivered at $3.25/gallon and the light towers are used in 10-hour shifts 20 times throughout the month. Savings for LED resulted in savings of up to $162.50 per month or $1,950 per year. That's a sizable figure that alone is an advantage to the higher purchase cost of LED.
"LED fixtures will also operate for at least 50,000 hours, meaning they will outlive the light tower that houses them," adds Bivins. “Compare that with the relatively short lifespan of halogen bulbs and the cost and hassle of replacing them. LED lamps are more durable and do not break when moving the lighting tower over rough terrain; this is something that happens all too often with halogen bulbs.”
The savings in fuel and operating costs can be particularly striking for contractors who routinely use light towers on construction sites. And there are other benefits as well.
“Additional runtime for LED alone results in savings in fuel use, which could be a huge cost reduction for the longer time the light tower will be used,” says Eric Massinon, business development director for Chicago Pneumatic. "A lighting tower that turns the light on and off automatically, when used with a sensor option, combined with longer runtime can mean you won't even need to visit it for up to two weeks."
Of course, time and cost savings are important for every employee and project owner. “Think of a road construction site and an endless array of light towers. All of which will need to be turned on, off and routinely refueled, LED eliminates the task of sensor on/off while reducing refueling requirements. LED is more like daylight and emitted from a halogen bulb goes further from the light. The luminaires also open and close instantly.” says Massinon.
Both Big and Small “Elephants”
The big elephant in the room for LED is the initial purchase cost, and it's probably close to a few thousand dollars per light tower. But there are also baby elephants.
“The average LED light tower in the US uses 960 watts compared to 4,000 watts for halogen. Depending on how much space you plan for lighting, the application may require more LEDs. The effect is partially reduced because the white light emitted by the LED appears brighter,” says Ben Froland, product manager for lighting towers at Wacker Neuson. He states that the company plans to launch a new generation of LED for the new LTV light tower; the factory-fitted option is four 240 units. watt LED fixture.
"LED's depreciation over 10,000 hours is only 3% compared to 50% for MH," says Generac senior product manager JR Fraher. Unlike halogen, the white light produced by LED is not only more consistent, but can also be focused to be very specific to the application.
“Today we must not forget that LED is truly a first-generation invention,” he continues, “Technology is advancing so fast that new LEDs will be more powerful and cheaper than those on the market.”
A smaller "elephant" for LED is the engine's wet-stacking potential, as LED bulbs don't require as much power as halogen. Diesel engines love to run. Otherwise, they may not reach their optimum operating temperature, resulting in fuel not burning. It can cause dirty injectors, unseated rings, and other problems that shorten the lifespan.
However, this effect can be avoided by ensuring that the generator and motor are correctly matched for the light tower system. “Diesel engines all have unique operating characteristics due to design differences. Extensive testing in collaboration with engine manufacturers helped us select an existing light tower engine that is inherently light-loaded,” says Froland. It saves a lot of fuel. No need for additional components.” he concludes.
LED's elephants are small compared to their benefits. In addition to fuel and cost savings, Fraher states that like conventional bulbs, LEDs are suitable for any activity or application that requires lighting.
“LED bulbs provide a more soothing, natural light than traditional bulbs. As technology improves and more suppliers enter the production floor, costs will come down. The longer 215-hour runtime and 750-hour service interval for our two units help lower operating costs.” he adds.