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Spotlight: ENERGY EFFICIENT TECHNOLOGIES
And, although manual shades can typically achieve a useful daylight for new buildings that will potentially change the change the way
zone of 10 feet inside the perimeter windows, automated shades daylight impacts the tower. In addition, clouds and weather patterns
respond to real daylight conditions to extend the useful daylight zone are in constant flux around a building this massive. Localized, wireless
to 20 feet inside the perimeter. As such, automated shades have been window sensors, as opposed to rooftop daylight sensors, recognize
shown to save 83% more lighting energy than manual shades2. conditions such as the bottom half of the building experiencing cloud
cover, while the top half of the building is in full sun. Each shade zone
A recent study, conducted by Purdue University and Lutron will automatically adjust to the actual daylight conditions in the space,
Electronics, analyzed the benefits and energy-saving potential of solar- maximizing the use of daylight without compromising occupant
adaptive, automated shading systems. Results show that perimeter comfort.
private offices with daylight harvesting strategies in place can further
reduce lighting energy usage by 65% through the use of automated The wireless sensors also allow the shading system to be effective
shades3. without having to create specific operational models that become
ineffective as the environment changes. Solar adaptive software,
Building codes drive daylighting strategies in combination with the window sensors, ensures that the shades
One of the most powerful motivators to use daylight more effectively automatically and effectively adapt to the actual, not theoretical, daylight
is code compliance. As utilities struggle to meet the ever-increasing conditions.
demand for power, federal and state agencies are stepping in to regulate
energy use and mandate compliance by strengthening building codes As the tower is completed, spaces are further defined, and tenants
to support energy savings and sustainable building design. Daylight occupy each space, the Lutron shading system and wireless sensors
harvesting strategies are key elements in these codes. allow shading controls to quickly adapt and accommodate changes
without expensive, disruptive rewiring or complicated reprogramming.
Standards and guidelines developed by the American Society The software includes an easy-to-use wizard accessible from an iPad or
of Heating, Refrigerating and Air-Conditioning (ASHRAE) are now iPhone, allowing end-users to make programming adjustments in the
mandated by the Department of Energy. As of October 18, 2013, all affected space, and in real time.
state commercial building codes must meet or exceed ASHRAE/ IESNA
90.1-2010 standards that include mandatory requirements for daylight Changing the paradigm for daylight control
harvesting technology. Other building standards, including IECC and New construction often uses daylight-friendly glass and steel design
California’s Title 24, are following suit by including similar daylighting to ensure energy-efficient, comfortable, code-compliant buildings. As
requirements in their updated recommendations. buildings use daylight more efficiently, they will be fundamentally less
dependent on electric light, and more reliant on adaptive, unobtrusive
Buildings can meet codes with manual shades and standard shading controls to enhance the occupant experience while reducing
technology mandated by the 90.1–2010 “Daylight Zone Requirement.” energy use.
Or, buildings can exceed codes and realize their full potential with
automated shades and wireless technology. By designing the same Editor’s Note: Gensler will be presenting details of the Shanghai Tower project
space with wireless technology and automated shades, the initial cost is during the Realcomm|IBcon Opening General Session.
slightly higher, but the return on investment is significantly better.
1 Williams et.al., “Lighting Controls in Commercial Buildings”, Leukos Vol 8, Number 3
The Shanghai Tower’s intelligent facade January 2012 pp. 161-180.
The Shanghai Tower, now under construction in one of world’s leading
financial centers, will utilize automated shade control and solar adaptive 2 It should be noted that the same study concluded that similar levels of savings are
available from other controls strategies such as occupancy sensors, personal dimming
software throughout its control and institutional tuning. Since this article is about daylighting, we will focus on
121 occupied floors. The that strategy here.
structure, designed by Gensler
Architects, uses more than 3 Lutron Electronics Co., Inc. worked with Purdue University to analyze the benefits and
13,000 automated shades savings potential useful daylight zone up to 10 feet of Lutron’s Hyperion automated
and hundreds of wireless shading systems. The results showed the impact of how automated shades signifi-
window sensors to ensure that cantly reduce annual lighting energy usage. Savings are based on energy simulation
shades can respond to local of a perimeter private office with a lighting power density of 0.9 W/ft., a standard clear
daylight conditions, providing double pane glass, and a shade fabric with 5% transmittance and a 76% reflectance.
consistent, comfortable Values shown are the average of three window to wall ratios: 20%, 40%, and 60%.
daylight in the building Daylight harvesting system required.
interior.
Brian Dauskurdas is Director, Global Energy Solutions
Shanghai is a city with Lutron Electronics. He has been intimately involved
experiencing tremendous change and growth. The shading system in the specification, construction and commissioning of the
chosen for the Shanghai Tower has to effectively accommodate largest buildings in the world. In his current role, Brian
continues to engineer and expand Lutron’s Global Energy
30 Realcomm Sales and Marketing Team. The team will be focused on
leading the company’s growth into existing building retrofits.
