[an error occurred while processing this directive]While “retro” in its Art Deco appearance, the Empire State Building is now forward-looking in practice; with its recent improvements in sustainability, retrofit, is the more apt descriptor. The structure is currently undergoing a $500 million upgrade program to become more energy efficient as its owners seek to reduce energy and water usage costs. The benefits will have a ripple effect, with other savings projected to come from a reduced building operations budget due to lower maintenance and repair costs, and expected income from rent and occupancy in light of the updated services for tenants.

Over 60 energy efficiency measures were analyzed in order to achieve optimal results, with eight selected that work in a comprehensive manner for best whole-building performance. The measures include:

1. Radiative Barrier - More than six-thousand insulated reflective barriers behind radiator units located on the perimeter of the building will be installed. For additional benefit, the radiator will be cleaned and the thermostat will be repositioned to the front side of the radiator.
2. Tenant Demand Control Ventilation - CO2 sensors for control of outside air introduction to Chiller Water Air Handling and DX Air Handling Units will be installed. One return air CO2 sensor will be installed per unit.
3. Tenant Daylighting, Lighting, and Plugs – Reduction of lighting power density in tenant spaces is to be achieved by using ambient, direct/indirect, and task lighting, installing dimmable ballasts and photosensors for perimeter spaces that can operate with electric lights off or dimmed depending on daylight availability.
4. Balance of Direct Digital Controls (DDC) – The existing control systems at the Empire State Building will be updated. The proposed project design and layout is based on using Johnson Controls Metasys Extended Architecture BACnet controllers and includes Ethernet and BACnet risers with all necessary devices and equipment, ADX server/workstation, printer, software, and web access capability.
5. Chiller Plant Retrofit - This will include the retrofit of four industrial electric chillers (one low zone unit, two mid zone units, and one high zone unit) in addition to upgrades to controls, variable speed drives, and primary loop bypasses.
6. VAV Air Handling Units – Recommendations include a new air handling layout (two floor-mounted units per floor instead of four ceiling-hung units). Also, variable air volume units are to be used instead of existing constant volume units.
7. Building Windows - The existing insulated glass (IG) within the Empire State Building’s approximately 6,500 double-hung windows will be upgraded to include suspended coated film and gas fill. A mix of krypton/argon gas will be used between the glass and suspended film. This project will improve the thermal resistance of the glass from R-2 to R-6 and cut the heat gain by more than half, in addition to allowing for the recycling of all existing glass.
8. Tenant Energy Management - This initiative will allow for the independent metering of a greater number of tenants in the Empire State Building. Tenants will have access to online energy and benchmarking information as well as sustainability tips and updates.

The retrofit is currently underway and is projected for by the end of 2013. Work that is scheduled to be completed within the next 18 months will result in more than 50% of the projected energy savings.