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From page 6... ... 6C H A P T E R 3 This chapter provides a discussion of energy saving technologies for escalators and moving walkways. The discussion is divided into two sections that focus on (1) Read the entire page →
From page 7... ... Energy Saving Technologies 7 the years, LED purchase costs are still several times more than fluorescent lamps. Prices vary so shopping around will assist in price control, and decisions should consider life cycle costs. Read the entire page →
From page 8... ... 8 Airport Escalators and Moving Walkways -- Cost-Savings and Energy Reduction Technologies Benefits -- Installing capacitors can result in reduced electricity costs if the utility rate structure includes penalties for low power factor. A typical payback period is less than 2 years.8 Capacitors can increase system capacity (e.g., for generators, cables, transformers, etc.) Read the entire page →
From page 9... ... Energy Saving Technologies 9 efficiency of the motor; therefore, the energy consumption of the escalator or walkway can be greatly reduced by installing a high-efficiency motor (see Figure 3-3) Read the entire page →
From page 10... ... 10 Airport Escalators and Moving Walkways -- Cost-Savings and Energy Reduction Technologies Benefits -- Installing a high-efficiency motor on an escalator or walkway can greatly reduce operating costs. The operating cost of a motor can represent up to 97 to 98 percent of lifetime costs.14 For small motors that have high operating hours, the payback period for a high-efficiency motor can be as low as 7 months. Read the entire page →
From page 11... ... Energy Saving Technologies 11 There are several methods used by MEC manufacturers to accomplish this, but the end result remains the same: reduced voltage to improve efficiency and save energy for motors at low load. The method shown here is the Nola Method designed by the National Aeronautics and Space Administration (NASA) Read the entire page →
From page 12... ... 12 Airport Escalators and Moving Walkways -- Cost-Savings and Energy Reduction Technologies Intermittent Drive Overview of Technology -- An escalator equipped with an intermittent drive allows for twospeed operation. With an intermittent drive, the escalator speed can be reduced to a minimally accepted speed or to a complete stop depending on the variance received by local authorities. Read the entire page →
From page 13... ... Energy Saving Technologies 13 Benefits -- Installing an intermittent drive can result in energy savings of up to 25 percent depending on passenger load.16 The actual savings on a given escalator or moving walkway will depend on how often the unit is idle, but a recent study done by Portugal's University of Coimbra estimated that installing intermittent drives on an escalator or moving walkway could reduce total electricity use by about 28 percent. Limitations -- The intermittent operation of an escalator has limited applicability. Read the entire page →
From page 14... ... 14 Airport Escalators and Moving Walkways -- Cost-Savings and Energy Reduction Technologies Limitations -- An intermittent drive paired with a MEC can result in higher savings than either technology would achieve if installed alone. However, the limitations for both technologies still apply, even when paired together. Read the entire page →
From page 15... ... Energy Saving Technologies 15 Benefits -- A VVVF can reduce energy consumption of an escalator by up to 30 percent.18 In addition, VVVFs can increase the useful life of a motor. According to the Intermittent Escalator Study, controlling the speed of a motor can reduce maintenance costs by up to 2 percent per year.19 In addition to energy and cost savings, VVVFs allow for the most precise control of escalator speed when compared to other means of control. Read the entire page →
From page 16... ... 16 Airport Escalators and Moving Walkways -- Cost-Savings and Energy Reduction Technologies over time for a two-speed AC motor, an AC motor with a variable voltage controller, and an AC motor with a VVVF. The increase in current for the motor with a VVVF drive is more gradual than the increase for a two-speed motor or a motor with a basic variable voltage controller. Read the entire page →
From page 17... ... Energy Saving Technologies 17 condition. When the passenger load reaches enough mass to drive the escalator down without the assistance of the motor, the electric motor acts as a generator and energy is passed back through the output inverter section and feeds into the power reservoir. Read the entire page →
From page 18... ... 18 Airport Escalators and Moving Walkways -- Cost-Savings and Energy Reduction Technologies Technologies Not Included in the Financial Tool Although the following technologies are often recommended as energy saving options for escalators and moving walkways, the report authors chose to exclude these technologies from the financial tool for one of the following reasons: • The technology may result in low energy savings and, consequently, long payback periods; • It may no longer be available for installation; or • Limited data may be available, that does not allow for analysis to determine the costs and benefits of the technology. Technologies excluded from the financial tool and discussed in the following section include: • Regenerative drives, • Wye-delta configured motors, • Direct drives, and • Intermittent drives with motor efficiency controller and variable voltage–variable frequency drive. Read the entire page →
From page 19... ... Energy Saving Technologies 19 Three-phase motors have three windings. On some motors, all six ends are utilized (two ends per winding) Read the entire page →
From page 20... ... 20 Airport Escalators and Moving Walkways -- Cost-Savings and Energy Reduction Technologies Limitations -- This technology was not included in the financial tool since it is no longer provided by escalator or moving walkway manufacturers. Retrofits may not be possible without significant space changes, thereby making this a cost-prohibitive technology. Read the entire page →
From page 21... ... Energy Saving Technologies 21 where escalators are in constant use as this leaves little to no opportunity for long enough intermittent periods to generate reasonable savings. Retrofitting an escalator to run intermittently or replacing it with a new intermittent-run escalator also can be expensive. Read the entire page →
From page 22... ... 22 Airport Escalators and Moving Walkways -- Cost-Savings and Energy Reduction Technologies Technologies Overview Benefits Limitations Intermittent Drives with Variable Voltage– Variable Frequency Drives (VVVF) A VVVF is a motor controller that regulates the voltage and frequency delivered to a motor depending on the loading. Read the entire page →

From page 6...

... 6C H A P T E R 3 This chapter provides a discussion of energy saving technologies for escalators and moving walkways. The discussion is divided into two sections that focus on (1)