Cooling plant and controls upgrade improve facility’s energy grade an entire letter, from a “D” to a “C”

33 Greenwich Avenue, a landmarked cooperative building in Manhattan’s West Village, hired EN-POWER in late 2019 to upgrade its outdated electric screw chiller and cooling tower. Our engineers overcame multiple challenges to successfully replace the equipment on time with a far more efficient electric modular chiller plant and cooling tower, helping improve the building’s energy grade from a “D” to a “C.”

Originally, EN-POWER was hired to conduct its NYC Local Law 87 energy study and retro-commissioning in 2017. Our auditors discovered that the facility’s outdated electric screw chiller and cooling tower both suffered from major performance issues: the cooling tower fan constantly short-cycled (i.e., turned off and on), leading to resident noise complaints and inefficient operation, while the chiller’s performance and reliability had greatly degraded. The chiller’s unreliability was exacerbated by the fact that a single chiller unit was carrying the cooling load of the entire building—meaning when the chiller broke down, residents were left completely without cooling.

As part of the cooling system upgrade, our engineers chose a modular electric chiller because it could provide three critical features: redundancy in case of equipment failure, significantly increased energy efficiency, and minimal on-site construction, as it could be installed in pieces rather than requiring walls to be torn down. We selected high-efficiency motors and variable frequency drives (VFDs) to further reduce energy use. Our team also incorporated both new systems into the site’s existing Building Management System (BMS) to increase ease of operation and reduce client energy costs.

Our engineers overcame multiple challenges to ensure the systems were finished on time in April 2020, including disruptions from COVID-19 lockdowns and securing rigging and permitting approvals from multiple NYC agencies, including the Landmarks Preservation Commission, FDNY, and Department of Buildings, as Essential Construction per COVID Executive Order 202.6. These upgrades helped the building reduce its energy use and carbon footprint. EN-POWER also secured $13,000 in incentives for the project.