Retrofit Project at Empire State Building Aims to Cut Energy Use by Nearly 40%
Using the Empire State Building as a test case and model, environmental consulting, non-profit, design and construction partners – including the Clinton Climate Initiative, Rocky Mountain Institute, Johnson Controls Inc. and Jones Lang LaSalle – recently unveiled an innovative process for analyzing and retrofitting existing structures for environmental sustainability.
The more than $500 million upgrade program presently underway at the building is the first comprehensive approach that integrates many steps to use energy more productively. It is expected to reduce energy consumption by up to 38% and will provide a replicable model for similar projects around the world. Work has already commenced, and building systems work is slated to be completed by year-end 2010.
The balance of the work in tenant spaces should be concluded by end of 2013. Work that is scheduled to be completed within 18 months will result in more than 50% of the projected energy savings. The balance will be an additional 36 months, completed by 2013.
The project will prove the viability for energy efficiency retrofit projects to dramatically increase building energy efficiency and reduce its overall carbon output with sensible payback periods and enhanced profitability.
At the end of the project definition process, the team analyzed the steps to be taken in conjunction with other steps towards sustainability as part of the Empire State ReBuilding program within the framework of the existing USGBC Leadership in Energy and Environmental Design (LEED)rating system. Internal calculations show that the Empire State Building will be able to qualify for GOLD certification for LEED for Existing Buildings, and ownership intends to pursue such certification.
“Beginning in February 2008, the Empire State Building has been used as a test bench to create a replicable process to reduce energy consumption and environmental impacts,” said Anthony E. Malkin of building owner, Empire State Building Company. “Most new buildings are built with the environment in mind, but the real key to substantial progress is reducing existing building energy consumption and carbon footprint.”
The project partners used existing and newly created modeling, measurement and projection tools in a new and repeatable process to analyze the Empire State Building and establish a full understanding of its energy use as well as its functional efficiencies and deficiencies. This provided actionable recommendations along a cost-benefit curve to increase efficiency and without harming bottom line performance.
In reviewing more than 60 optional activities, the team identified eight economically viable projects, applicable to building-wide renovations, electrical and ventilation system upgrades and tenant space overhauls that will provide a significant return on investment, both environmentally and financially.
With an initial estimated project cost of $20 million, additional savings and redirection of expenditures originally planned in the building’s upgrade program, and additional alternative spending in tenant installations, the Empire State Building will save $4.4 million in annual energy savings costs, reduce its energy consumption by close to 40%, repay its net extra cost in about three years, and cut its overall carbon output through eight key initiatives, including:
1. Window Light Retrofit: Refurbishment of approximately 6,500 thermopane glass windows, using existing glass and sashes to create triple-glazed insulated panels with new components that dramatically reduce both summer heat load and winter heat loss.
2. Radiator Insulation Retrofit: Added insulation behind radiators to reduce heat loss and more efficiently heat the building perimeter.
3. Tenant Lighting, Daylighting and Plug Upgrades: Introduction of improved lighting designs, daylighting controls, and plug load occupancy sensors in common areas and tenant spaces to reduce electricity costs and cooling loads.
4. Air Handler Replacements: Replacement of air handling units with variable frequency drive fans to allow increased energy efficiency in operation while improving comfort for individual tenants.
5. Chiller Plant Retrofit: Reuse of existing chiller shells while removing and replacing “guts” to improve chiller efficiency and controllability, including the introduction of variable frequency drives.
6. Whole-Building Control System Upgrade: Upgrade of existing building control system to optimize HVAC operation as well as provide more detailed sub-metering information.
7. Ventilation Control Upgrade: Introduction of demand control ventilation in occupied spaces to improve air quality and reduce energy required to condition outside air.
8. Tenant Energy Management Systems: Introduction of individualized, web-based power usage systems for each tenant to allow more efficient management of power usage.
Recently, several initiatives have been launched, including the CCI Building Retrofit program and New York City’s PlaNYC in 2007, which aim to reduce the significant carbon footprint of existing structures in major cities. The pilot program launched at the Empire State Building moves from theoretical and directional steps to quantifiable action plans which can be broadly adopted around the world.
The full analysis process is available online as open-source materials for public use at www.esbsustainability.com and www.esbnyc.com.