Empire State Building Retrofit Surpasses Energy Savings Expectations
The energy efficiency retrofit of the Empire State Building had the makings of a great story right from the start. Visionary building owner Tony Malkin, in an effort to revive the 2.7 million-square foot New York landmark, assembled a team of leading organizations—Rocky Mountain Institute, Johnson Controls, Jones Lang LaSalle, and the Clinton Climate Initiative—to develop a retrofit program that would not only maximize energy savings, but build a strong economic case, saving 38 percent of the building’s energy and $4.4 million annually—and created 252 jobs to boot.
Now, one year after the core retrofit is complete, the Empire State Building story is not only inspirational, but also very real. Today, Malkin and partners announced that the building exceeded its energy-efficiency guarantee by five percent, saving $2.4 million and establishing a commercial real estate model for reducing costs, maximizing return on investment, increasing real estate value, and protecting the environment.
What ultimately set the Empire State Building apart are integrated design, and a ‘right-steps in the right-order’ model that can be applied to any building of any size.
“There aren’t a lot of people who give thought to what should we be designing. What RMI’s involvement was the special sauce:’ Looking at things differently from the pre-ordained fashion that most people have been trained in,” Malkin said. “They helped take this project and turned it into a language that anyone— liberal or conservative—can understand, which is make an investment, get a return, and the return happens to produce a better overall result without compromise.”
According to Amory Lovins, RMI chief scientist, RMI achieved this by working with powerful partners who have tough problems. The decision to reposition the world’s most famous office building as a leading example of an economically viable, energy efficient commercial retrofit was made for its potential to fundamentally disrupt the market.
“We knew that by retrofitting the Empire State Building, we would catch the world’s attention,” Malkin said. “Through this project, we set out to prove or disprove energy efficiency retrofits’ economic viability. The program is designed to be open source, free, and widely available—so please rip us off.”
With the balance of the project to be finished as new tenants build out high-performance workspaces, not only is the building already more energy efficient, but it is also estimated to have saved 4,000 metric tons of carbon, the equivalent of that offset by 750 acres of pine forests. Once all tenant spaces are upgraded, the building will save $4.4 million a year, a 38 percent reduction of energy use that will cut carbon emissions by 105,000 metric tons over the next 15 years.
In dense urban settings like New York City, commercial buildings account for up to 75 percent of energy used. If every commercial building in New York City followed this blueprint, carbon emissions would be reduced by 4 million tons—the equivalent to that generated by a typical coal-fired power plant.
“If you want a sound solution to the coal issue, you need to get serious about designing and running buildings very differently,” said Amory Lovins, RMI chairman and chief scientist. “This is not a problem of technology and economics, but of adoption. We need to take to scale what is done.”
Making the Business Case
“First and foremost, making the Empire State Building energy efficient was a sound business decision that saves millions of dollars each year,” said Anthony Malkin of the Empire State Building Company. “Building owners and operators who are looking to cut costs while improving the value of their buildings can use energy efficiency to accomplish these goals. We now have a proven model that works.”
Several measures in particular helped to ensure an informed financial decision-making process and ensure a sound economic outcome. These included:
- The use of Life Cycle Cost Analysis
- Piggybacking energy upgrades on planned improvements
- Incorporating energy modeling into the design process to identify options of energy efficiency measures
- Using a hybrid of the ESCO model and owner investments to finance the upgrades
- Incorporating tenant energy reduction measures.
“All portfolio managers and real estate owners to some extent have been concerned with energy efficiency, and they’ve done small things. What this project shows is that it actually makes sense e to make large and significant energy efficiency improvements, not the five- to-10 percent type things, but the 20 to 30 percent and more type of improvements, and that there is a business case for doing so,” said Clay Nesler, VP of global energy and sustainability with Johnson Controls.
A total of eight efficiency measures performed jointly by Johnson Controls and Jones Lang LaSalle were responsible for a total first-year savings that added up to $4,393,796. Here’s how it all breaks down according to a report produced by Johnson Controls, Jones Lang LaSalle, and W&H Properties.
Radiator Insulation and Steam Trap Savings
Total savings: $491,191
More than 6,000 insulated reflective barriers were installed behind radiator units located on the perimeter of the building. Prior to this upgrade, about half of the heat radiated into the usable space, while the other half helped to heat New York City. This barrier reflects back most of the heat into occupied space—where it is intended to go.
Total savings: $338,508
The buildings 6,500 existing double-hung windows were dismantled and rebuilt onsite to include a suspended coated film and gas fill. This more than tripled the insulating value of each window, increasing occupant comfort, blocking winter heat loss three-times better than the old windows, reducing heating and cooling loads, blocking ultraviolet rays to protect occupants and furnishings, and enhancing daylighting.
In addition, the advanced glazing along with improved lighting and office equipment cut the building’s peak cooling load by one-third. The old chiller plant could then be renovated, rather than replaced and expanded—saving more than $17 million of budgeted capital expenditure. That capital cost savings helped pay for other projects and cut the overall incremental simple payback for the retrofit to three years.
Direct Digital Controls and Demand Control Ventilation
Total savings: $858,305
This measure involved upgrading the existing piecemeal and primarily pneumatic control systems at the Empire State Building to comprehensive, consistent digital controls, and the installation of CO2 sensors for control of outside air introduction to the air-handling units. Benefits include reducing cooling and heating demand, monitoring of indoor air quality, increased occupant comfort, and reduced energy bills.
Chiller Plant Retrofit
Total savings: $675,714
The chiller plant retrofit project included the improvement of four industrial electric chillers in addition to upgrades to controls, variable speed drives, and primary loop bypasses.
Tenant Energy Management
Total savings: $386,709
This project provides tenants with access to online energy and benchmarking information, as well as sustainability tips and updates. Tenants in the Empire State Building have access to a digital dashboard showing energy use in real time, and comparing it to past use and other tenants.
Tenant Daylighting, lighting and plugs
Total savings: $940,862
This measure—the biggest energy saver—reduced lighting power density in tenant spaces, by installing dimmable ballasts and photosensors for perimeter spaces and provided occupants with a plug load occupancy sensor for their personal workstations. Benefits include reduced utility costs for tenants, lower cooling demand due to less heat from electric lights and equipment, and improved visual quality.
VAV Air Handling Units
Total Savings: $702,507
As tenant turnover occurs, existing constant volume units are replaced with variable air volume units, using a new air-handling layout (two floor-mounted units per floor instead of four ceiling-hung units). VAV air handlers are more intelligent, and provide greater control—leading to not only costs savings, but also other benefits including greater occupant comfort and control, and reduced electricity demand.
“Until now, the energy savings were all theoretical and all based on careful energy modeling,” said Eric Harrington, analyst with RMI’s buildings practice. “Now that we have a year of utility data, the Empire State Building deep energy retrofit story is proven to work.”