The Project at a GlanceDownload
|TPG Architecture LLP
|Savanna (now VGBO Penn Plaza LLC)
|31 Penn Plaza, New York, NY
|40,000 square feet
In 2013, TPG Architecture, an architectural firm headquartered in New York City, signed a lease for 40,000 square feet on floors 4 and 5 at 31 Penn Plaza, a 440,000-square-foot, 18-story office building located between Sixth and Seventh Avenues in Midtown Manhattan. The overarching goal of the buildout was to create an office space that demonstrates energy efficiency’s strong return on investment, which would serve as a model for design clients. To help achieve that goal, TPG decided to follow the Tenant Energy Optimization process—a proven, replicable approach that integrates energy efficiency into tenant space design and construction and delivers excellent financial returns through energy conservation.
|Floors 4 and 5 buildout||Projected results*|
|Annual electricity reduction||139,077 kWh3.4 kWh/SFkWh / kWh/SF|
|Total electricity savings over lease term||1.5 GWh37.9 kWh/SFGWh / kWh/SF|
|Adjusted incremental implementation cost||$81,214 total$2.01/SFTotal / SF|
|Total electricity cost savings over lease term||$275,372 total$6.83/SFTotal / SF|
|NPV of project investment||$131,450 total$3.26/SFTotal / SF|
|ROI over lease term||162%|
|Payback period (with incentives)||3.2 years|
Executing the Process
Design and Construction
TPG was aware of other tenants who had used the Tenant Energy Optimization process and recognized that applying the process to its own space was an opportunity to spotlight its design capabilities in conjunction with demonstrating a strong business case for investment in energy efficiency measures. TPG assembled a project team to help execute the process. The energy consultant, Integral Group, had experience executing projects like this in other tenant spaces.
The team outlined energy performance goals that aligned with TPG’s overall corporate sustainability targets and developed an extensive list of energy performance measures (EPMs) to be considered for implementation in the final buildout. EPMs are technologies and systems that aim to reduce energy use through efficiency and conservation. They are also frequently referred to as energy conservation measures (ECMs).
After analyzing potential energy performance, incremental costing information, and cost savings projections, the team was able to choose a package of EPMs that would meet the energy and financial goals of the company. The EPMs chosen to be implemented in TPG’s space on floors 4 and 5 include the following:
|Energy performance measure (EPM)||Target area||Electricity reduction||Annual cost savings||Incremental first cost||Simple payback|
|As-designed lighting power (1.08 W/SF)||Lighting||36,424 kWh/yr5.7%kWh/yr / %||$6,556||$0||Immediate|
|Daylight harvesting||Lighting||25,246 kWh/yr3.9%kWh/yr / %||$4,544||$17,489||3.8 years|
|Local lighting occupancy sensors*||Lighting||6,483 kWh/yr1.0%kWh/yr / %||$1,167||$18,600||15.9 years|
|ENERGY STAR equipment||Plug load||28,224 kWh/yr4.4%kWh/yr / %||$5,080||$0||Immediate|
|Demand-controlled ventilation (DCV)**||HVAC||1,639 kWh0.3%kWh / %||$295||$18,000||61 years|
|Eliminate humidification in main distribution frame room||Data center||4,312 kWh/yr0.7%kWh/yr / %||$776||$3,500||4.5 years|
|Computer shutoff software and occupancy sensor* strips||Plug load||36,749 kWh/yr5.7%kWh/yr / %||$6,615||$14,625||2.2 years|
** DCV is designed to control the exchange of fresh or outside air. This EPM may improve indoor air quality and occupant comfort and does not always result in energy or cost savings if DCV equipment is controlled primarily by base building energy or not closely monitored.
Measurement and Verification
|Companies and Roles|
Energy project director
|JRM Construction Management
After completion of the buildout, the energy consultants returned to perform measurement and verification (M&V) to ensure that the implemented EPMs were performing as intended in TPG’s space. M&V was conducted over the course of a ten-day period, once the space was fully occupied and operational. M&V confirmed that the implemented EPMs were operating as designed and providing the level of energy and cost savings anticipated. The energy consultant provided several recommendations following the ten-day monitoring period:
- TPG should verify lighting control schedules and occupancy sensors are properly set up to allow lighting power to drop down to the minimum required for emergency exit at night. Metering showed overnight lighting power consumption to be on the higher end of normal for systems of this type.
- TPG should verify heating, ventilating, and air-conditioning (HVAC) system scheduling. The HVAC fans were running (at a reduced speed during unoccupied hours) 24 hours a day. Further savings are possible if HVAC fans are shut down during unoccupied hours.
- TPG should verify configuration of plug-load management to reduce nighttime loads to the same as weekend levels. The metered plug-load profile suggested that a significant amount of plug load is not shutting off at night during the week but is shutting off during the weekend.
Employees’ reactions to the new space have been overwhelmingly positive, and company executives have found the space more interactive and collaborative. The new space is nearly 100 percent open, which allows management to sit near teams and give support more easily. The new space is lighter and brighter, and the design has pushed employees to be more mobile and flexible in where they work.
When TPG gives office space tours, it highlights the EPMs and sustainable measures it has implemented to guests and potential clients. For instance, signs note the use of ENERGY STAR–rated equipment and explain the installed daylight-harvesting system and occupancy sensors.
“It helps to tell our story,” said TPG associate Samantha McCormack. “You may not realize that these fixtures are there, and clients are interested in how to implement these sustainable technologies without having to go for certifications.”