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14 Strategies to Save
Up to 70% in Energy
Costs Using the Latest in
Warehouse Lighting
...and More
White Paper: 14 Strategies to Save up to 70% in Energy Costs Using the Latest in Warehouse Lighting...and More
Daintree Networks Inc.
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2
Executive Summary
There is no place for poor lighting in warehouses or distribution centers. These facilities support a variety of important tasks
from picking and packaging to shipping and receiving, light assembly and even office work. Since multiple functions are
often performed in the same area, lighting takes on even more significance because of the need for different light levels.
Warehouse managers are looking for high quality levels, but at a much lower cost.
Now there is a way to benefit from technology advances to ensure the most effective lighting while also providing immense
energy savings.
Today’s advanced lighting control offers the following:
- Energy savings of up to 70%
- Flexibility in scheduling lighting operation
- Improved lighting quality and increased occupant satisfaction
- Ability to track energy costs and savings in real time
- Ability to control lighting on-site or remotely from a web-based interface, like a smart phone or wireless computer
It is also possible to combine lighting control with the ability to manage other power sources for even greater returns, as we
will see later in this paper.
Lighting control has a tremendous capacity for saving energy and money in commercial buildings. About $200B is spent
globally on lighting energy each year, around half of which comes from commercial buildings. And yet, much of that energy
is still wasted – lights are left on in unoccupied areas and rooms are consistently over-lit, even when technology tools exist
to solve these problems.
A common misconception of a “lighting control solution” is that it is simply an occupancy sensor, turning the lights on and
off in a single room. And while this can certainly save energy and money, it’s just the simplest of many control strategies
designed to provide more intelligent, sustainable buildings. Today’s lighting control systems have moved beyond the stand-
alone occupancy-based products to provide true system-level control over lighting. If properly applied, the result can be
tremendous savings, better occupant comfort, improved building management, and more.
The purpose of this white paper is to describe 14 distinct control strategies enabled by today’s most advanced lighting
control systems, and discuss the technology attributes that are required in order to take advantage of these strategies. Only
by utilizing technology that is intelligent, networked, wireless and open can lighting control solutions provide the
most comprehensive savings and control.
White Paper: 14 Strategies to Save up to 70% in Energy Costs Using the Latest in Warehouse Lighting...and More
Daintree Networks Inc.
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3
Types of Lighting Control Systems
There are a myriad of lighting control technologies, systems, and components
on the commercial market. Generally, though, lighting control can be divided by
capability into room-based control, and “advanced” or networked control. For
the purposes of this paper, we can further divide the advanced category into
“traditional” advanced systems – wired and proprietary – and the new generation
of open, wireless control. As we will show, these distinctions are more than aca-
demic – they represent substantial differences in capabilities and potential savings.
Room-based Control: Most lighting control installations today still
fall into the category of room-based control. These solutions are not true lighting
control systems, but rather individual components that provide a single lighting
control strategy. As an example, an individual occupancy sensor can be connected
via low voltage wiring to a set of light fixtures in a room, and this process can be
repeated in the next room and so on. The result is to add automated occupancy
control to each of those rooms, individually. The same process can be repeated
with other control components.
Centralized Control: The next step up in capabilities is a centralized control
system – for example, a lighting panel or a Digital Addressable Lighting Interface
(DALI)-based solution. In these systems, each lighting element (sensors, wall switch-
es, fixtures, etc.) is hard-wired back to a centralized controller, panel or computer. In
other words, lighting in these solutions is controlled as a system or network.
These systems typically combine a discrete set of control capabilities (or
“strategies”) such as scheduling, occupancy, daylighting, etc., and provide a
physical interface for controlling any device hard-wired to the panel. Such systems
are
often proprietary, with a single vendor providing both the controller and the
devices being controlled (which are only compatible with each other).
Next Generation Control: The next generation of control systems
builds upon the advantages of advanced control but removes the limitations.
Wireless networking enables larger-scale systems with control that can be
accessed from anywhere, and adjusted without physical wiring. Open standards
eliminate the restrictions of proprietary systems, enabling a single control system
to utilize control devices from a variety of vendors. Integration with non-lighting
products enables savings that go beyond lighting, into areas such as HVAC and
plug loads. The result is an even more comprehensive set of energy monitoring and
management tools, with centralized control.
Advantages of Advanced Control
In short, more advanced control equates to greater financial savings. Each individual
control strategy brings savings; when applied together, though, these savings stack
up. For example, while a room might reduce lighting energy usage by 30% through
occupancy sensing, that same room could save 60% by using occupancy sensing,
daylighting and scheduling at the same time. And several control strategies can
only be implemented with an advanced, networked system, making such systems
a requirement in order to realize the greatest savings.
Savings from lighting control can come from several sources. The primary source
is reduction in energy usage. The purpose of the most commonly-adopted control
strategies (occupancy sensing, scheduling, etc.) is to eliminate unnecessary lighting,
thereby reducing energy usage and saving energy costs. Savings in some advanced
systems can also come from other sources as well – for example, by reducing
lighting maintenance requirements or reducing the time and labor associated with
managing lighting. And of course, government and utility incentives tend to reward
greater energy reduction, providing even more savings.
Savings from lighting control systems are also not static – they change over time.
With more basic installations, energy savings tend to shrink over time, as the orig-
inal design of the solution diverges from the current needs of the building and its
occupants. More advanced systems can “self-correct” or adapt to retain value over
time. And the most intelligent systems can actually improve their value over time, by
automatically recognizing potential areas of energy savings and improvement. Finally,
open standard systems offer the ability to add new capabilities in the future that go
beyond lighting, for even greater value over time. These applications will be discussed
later in this paper. The intelligence of advanced control systems provides other benefits
that basic control cannot offer, above and beyond simple financial savings:
• Greater centralized control: For many building owners and operators,
gaining centralized control and visibility over their lighting and other energy loads is
a benefit in itself, offering better management and reporting.
• Occupant comfort: The most intelligent lighting control solutions enable
lighting that automatically or manually adapts to each occupant’s needs, for greater
comfort and productivity. Balancing savings with comfort is a critical function that
requires an adaptable system.
• Green certifications: Advanced control systems can provide valuable points
and credits towards LEED and other similar programs, above and beyond the credits
that basic control offers.
• Regulatory compliance: Regulatory measures such as ASHRAE 90.1 and
California’s Title 24 are increasingly requiring more advanced lighting control
measures. Over time, basic control technology will no longer be sufficient to meet
building codes.
Control Strategies
Below, we will detail all of the common energy-saving lighting control strategies
available today, as well as several emerging strategies and those that extend be-
yond lighting. These are organized generally from most common to most innovative.
Common Lighting Control Strategies: These strategies form the core of most lighting
control systems.
• Dimming: Although not always considered a true control strategy, dimming
technology is utilized in several other strategies. Many lighting power supplies (e.g.
ballasts, LED drivers) enable fixtures to be dimmed. Dimming the light to a fraction
of its brightness will also use a fraction of the energy, allowing for many of the
following strategies to reduce energy usage. The exact relationship between the
brightness and the power used depends on the unique profile of the power supply.
In its simplest form, dimming fixtures are paired with a dimmer switch, for manual
dimming control. Dimming capabilities vary widely, from step functions up to full,
smooth control over precise light levels.
White Paper: 14 Strategies to Save up to 70% in Energy Costs Using the Latest in Warehouse Lighting...and More
Daintree Networks Inc.
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4
• Occupancy sensing: This is perhaps the most common of all lighting
control strategies. A motion sensor (also known as an occupancy sensor) detects
movement within its field of coverage, using Passive Infrared (PIR), ultrasonic, or
other sensing technologies. Based on movement detection (or lack thereof) for a
pre-defined period of time, lights can be automatically turned on or off. In this way,
lights can be automatically turned off when a space is not in use.
More sophisticated control solutions allow occupancy settings (such as on/ off lev-
els, time delays, etc.) to be dynamically set or changed based on time, location and
other inputs. Occupancy sensors can be built as stand-alone devices, or integrated
directly into wall switches, light fixtures, furniture and more.
• Scheduling: Scheduling is another method of eliminating unnecessary lighting
usage when building occupants are not present. Most centralized lighting control
systems provide some form of lighting schedule, the simplest example being a
system that automatically turns off the lights after work hours. This is a “brute
force” method of reducing energy usage, but can be effective. Some systems allow
local user override of the schedule (via a wall switch), and the more sophisticated
systems can create more complex schedules that alter other strategies based on
time of day, day of week, time of year, etc.
Advanced Lighting Control Strategies: These strategies are not
as commonly used as those above, but are becoming more widely available.
• Daylight Harvesting: Also known as Daylighting, this is the practice of
automatically reducing artificial light levels when ambient daylight (from windows,
skylights, etc.) is available. Daylighting systems typically utilize a photocell sensor
(though alternate sensor technologies do exist), which measures ambient light.
Based on the reading from the sensor, an algorithm will determine the appropri-
ate level of artificial light, or whether the lights can be turned off altogether, and
the control system will take action. A properly-designed daylighting system can
provide substantial savings in window-facing areas.
Daylighting can work effectively with both dimming and non-dimming lighting,
and like occupancy sensors, photocell sensors come in a variety of forms and can
be integrated into other products. A similar concept is commonly used in outdoor
lighting, where integrated photocell sensors automatically switch lights on at dusk
and off at dawn.
• Task Tuning: This strategy goes under several names. The core concept is
to reduce the maximum light output of each individual space to precisely meet
occupant needs. Because light levels are often over-designed, or made consis-
tent across a building despite the different needs of occupants, many spaces are
over-lit. Some control systems offer the capability to create lighting zones and
determine a “tuned” maximum light level that is lower than 100%. As an example,
an occupant working with a computer monitor all day may not need the designed
light level, and their area could be tuned so that the maximum level is 70%.
The related concept of Lumen Maintenance stems from the fact that most lighting
experiences a slow depreciation of light output over its lifetime. In this scenario,
light levels are tuned down initially, but over time the control system slowly tunes
levels back up to account for depreciation and maintain a constant output.
• Demand Response (DR): This strategy is less about saving money, and
more about earning money – by reducing peak energy demand at key times, and
being reimbursed by utilities to do so. A major goal of many utility companies is to
better distribute their load, reducing the demand for energy at the times of highest
demand (such as hot summer days). Lighting control systems can help by reducing
lighting load during those times, in response to a signal from the utility. Some
control systems offer Auto-DR technology: the ability to respond to a DR “event”
and reduce light levels automatically. Demand Response utility programs vary
widely, but some offer significant reimbursement (such as $300 / kW) for making a
building’s load available for reduction.
• Personal Control: Various studies have proven the positive impact of a work-
er’s environment – and their control over that environment – on their productivity
and happiness. It has also been found that when occupants are given personal
control over lighting, their energy usage tends to be lower. Advanced lighting
control systems can use various forms of personal dimming to provide this control,
ranging from remote controls to desktop dimming switches to “virtual” switches
online, on a desktop computer or on a phone.
• Energy Management: This strategy typically refers to a software system
that enables a building or facilities manager to visualize, report on and adjust their
energy usage. It is often said that you cannot manage what you cannot measure
– and centralized energy management software tools provide the capability to do
both, in order to test and measure the success of lighting control.
Energy management saves energy over time by providing ongoing improvements
to all of the other control strategies. As an example, analysis of building energy us-
age compared with occupancy data over a month might point out that the office’s
kitchen area sees occupants throughout the day but only for short periods of time.
The system could recommend reducing the occupancy-based off-delay in this area
from 15 minutes to 5 minutes, and would measure the additional savings of that
action. This type of ongoing recommendation and improvement is also known as
Continuous Commissioning.
Lighting-Related Control Strategies: These strategies begin to
extend beyond the standard goal of reducing lighting energy usage, and provide
other lighting benefits.
• Automated Maintenance: By monitoring and measuring energy usage at
individual fixtures, some control systems can provide the capability to know when
a lamp is out, or a sensor or ballast is malfunctioning. Likewise, similar information
can be used to make an educated guess about when maintenance will be required.
Finally, some systems can manually or automatically reconfigure in the case of a
failure – for example, if an occupancy sensor fails, the lights can be re-associated
with a neighboring sensor until maintenance replaces it. Together, all of this infor-
mation can be used in an energy management system to improve the scheduling
of maintenance calls, reducing the frequency (and cost) of lighting maintenance.
White Paper: 14 Strategies to Save up to 70% in Energy Costs Using the Latest in Warehouse Lighting...and More
Daintree Networks Inc.
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5
• BMS Integration: Some advanced lighting control systems enable integration
with a facility’s Building Management System (BMS), typically via BACnet or anoth-
er open protocol. Through this integration, the user interface of the BMS can pro-
vide integrated control and management functions. Although this strategy doesn’t
save additional energy in itself, it does offer reduced management overhead (and
the associated lower cost) for buildings that want to manage HVAC, lighting and
other functions from a single console.
Beyond Lighting: These strategies extend a single control system beyond
lighting, to control (and reduce) other common energy loads.
• Plug load Control: Plug loads are an area of energy usage that is rarely con-
trolled but represents a significant amount of energy waste. Under this strategy, de-
vices that would be plugged into a standard plug strip or outlet (such as monitors
or desktop lamps) are instead plugged into a specialized “plug load controller”.
These loads can then be managed according to a schedule or associated with an
occupancy sensor. For example, a plug load controller can be set to automatically
turn off a desk lamp at the end of the day and whenever the user leaves his desk.
This reduces both wasted usage and the “vampire power” that some devices draw
even when off. Generally, wireless plug load controllers that are part of a central-
ized solution offer more sophisticated control options than standalone controllers.
• Temperature, Humidity, CO2, and other Environmental Monitoring:
One of the advantages of a centralized control system (especially wireless and
standards-based systems) is the ability to add applications onto an existing
network without the need to build out a new dedicated infrastructure. Several
emerging applications take advantage of environmental monitoring sensors, to
report on conditions in a facility and trigger alerts if those conditions exceed a
threshold. For example, some data centers closely track temperature and humidity
to avoid unplanned outages. In a lighting control solution that supports this appli-
cation, temperature and humidity sensors can be added to the network and report
real-time data.
• Wireless Thermostats: Building Management Systems typically manage the
thermostats and other HVAC devices within the building. As those devices have
begun to roll out with wireless communications capabilities, though, buildings have
balked at the requirement to build a dedicated wireless network just for thermo-
stats. A wireless lighting control network can be used to avoid this requirement,
routing wireless control messages to and from the thermostats via the lights. The
benefit is a single building control network, eliminating the cost of building sepa-
rate parallel networks. Lighting serves as an especially robust “base application”
for this network, due to the large number of lighting nodes (e.g. fixtures), and their
even, distributed coverage throughout the building.
• Other Independent Building Systems: As with the environmental
sensors above, some standards-based control systems have the capability to add
control over a variety of other devices. Some examples include automated window
blinds, industrial fans, and security systems. By providing centralized control over
these devices, in addition to lighting, these advanced building networks can pro-
vide greater control from a single integrated solution and interface.
How to Take Advantage of the Most
Advanced Control Strategies
As detailed at the start of this paper, not every control system enables all of the
above strategies. While most systems offer a subset, many are constrained due to
their choice of technology, making some of the most valuable strategies impossible
to implement. For example, a lighting control system that isn’t networked will not
be able to provide a centralized control interface – it is a basic limitation of the
technology architecture.
In order to get the most out of a potential control system purchase, and enable all
of the above strategies, here are some of the key attributes to look for:
Networked: A networked architecture is what separates basic “room-level”
control from true control systems. Without some form of networking (wired or
wireless), it is impossible to take central control over lighting and therefore impos-
sible to take advantage of energy management, demand response, and many other
control capabilities. Non-networked control is also extremely difficult to manage,
maintain and upgrade.
Intelligent: Many control solutions tout “intelligence” as a feature – and it
is a critical one, but difficult to define precisely. In practice, intelligence in a control
system typically means a combination of multiple related attributes:
• Flexible configuration, allowing facilities managers and other users to more
accurately adapt to conditions and occupant needs. In other words, an
intelligent control system usually includes a powerful and feature-rich user
interface for setting or changing controls.
• Automated control algorithms that make decisions based on multiple inputs.
For example, an intelligent control system could combine ambient light
readings with time of day, day of week, location, user preference and more to
determine (and set) the appropriate light level.
• The ability to measure results, and the means to use that information to
improve results.
Simply having access to multiple control strategies does not necessarily make a sys-
tem intelligent –sophisticated software is required in order to determine how those
strategies should interact. It is important to look in-depth at a system’s capabilities,
and how it logically makes decisions, in order to determine if it meets your needs.
White Paper: 14 Strategies to Save up to 70% in Energy Costs Using the Latest in Warehouse Lighting...and More
Daintree Networks Inc.
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6
Wireless: As the number of end points in a building control system has
proliferated – lights, various sensors, wall switches, remote controls, computers,
plug load devices, and more – so has the complexity of reaching and communicat-
ing with each of these devices. In order to effectively control a device, the central
system must be able to communicate with it. Wired systems bridge this gap with
dedicated control wiring (or specialized power-line control wiring), but the more
devices in a system, the more complex and inflexible this becomes.
Wireless networking is an effective solution, eliminating limitations of which devic-
es can be controlled, where they can be placed, and so on. This is especially critical
in order to realize the most advanced control strategies, and those that extend
beyond lighting. Most wired systems, for example, were not designed to connect to
plug load controllers or environmental sensors, so there is physically no way to add
that capability. Wireless systems can connect to such devices easily, as long as they
speak the same language.
Open: As noted above, communications is a requirement of any control system
– the system must be able to receive data from devices and issue commands to
fixtures. But what “language” is used for these control messages? It can take many
forms, though most frequently the communications language is proprietary, and
created by the manufacturer of the control system. For example, a control manufac-
turer could create a sensor, a ballast and a control panel, and write the language
they use to communicate with each other. If a customer tried to use another
vendor’s sensor with that panel, they would not be able to understand each other
and would be unlikely to work together.
Proprietary systems have limited the growth of new and innovative control strat-
egies, because each vendor essentially starts from scratch in developing their own
system, and has the added overhead of upkeep on their proprietary communica-
tions protocol. This is changing with the introduction of “open” systems to the
lighting control market, based on well-accepted industry standards. In an open
system, a manufacturer chooses an existing communications language, and their
products can communicate directly with other manufacturers’ products.
There are many positive results of open systems – choice, trust, lower cost – but
perhaps the most important is their impact on innovation. Unlike proprietary
systems, a standards-based control system can use any standards-compliant device.
When multiple companies develop products based on the same open industry
standard, customers can take advantage of all their combined innovations. This
is how lighting control systems have begun to take advantage of energy savings
beyond lighting (for example, connecting to environmental sensors or wireless
thermostats) and will define the future of how new integrated energy strategies
will be developed.
Daintree Networks, Inc.
Daintree Networks, Inc.
5150 El Camino Real | Suite E-20
Los Altos, CA 94022 U.S.A.
Phone: +1 (650) 965-3454
email: [email protected]
www.daintree.net
Copyright © Daintree Networks, 2014. ZigBee is a registered trademark of the ZigBee Alliance. 802.15.4 is a trademark of the Institute of Electrical and Electronics Engineers (IEEE)
Common Lighting Control Strategies
Dimming: Enable fixtures to dim, for use in other strategies below Variable
Occupancy Sensing: Adjust lights based on occupancy detection Up to 40%
Scheduling: Dim and turn off lights according to a pre-set schedule Up to 40%
Advanced Lighting Control Strategies
Daylight Harvesting: Adjust electric light levels to take natural light into account, using photosensors Up to 20%
Task Tuning: Reduce maximum light levels based on requirements for each space Up to 20%
Demand Response: Reduce light levels at peak times based on automated signals from electric utilities Variable
Personal Control: Enable individuals to set light levels to suit personal preferences Up to 10%
Energy Management: Software for ongoing improvement in control settings and strategies Variable
Combined Lighting Energy Cost Savings Up to 70% of Lighting
Energy Costs
14 Strategies to Save up to 70% in Energy Costs Using the Latest in Warehouse Lighting...and More
Good lighting is critical in industrial buildings. These facilities support important tasks from picking to light assembly and even office work. Since multiple functions are often performed in the same area, lighting should adapt to different tasks.
Learn the strategies that are proven to improve energy savings, occupant comfort and building management.