Commercial & Industrial

City Crescent
Building

Comprehensive Energy Efficiency Treatment

Project resulted in an annual energy reduction of 3.7 million kWh

OpTerra Energy Services recently completed a comprehensive energy efficiency upgrade at the landmark City Crescent building in the heart of downtown Baltimore.

OpTerra Energy Services, working together with building ownership and management, successfully designed and implemented this comprehensive energy efficiency project at City Crescent, which will result in an annual energy reduction of 3.7 million kWh. These energy savings amount to an impressive carbon footprint reduction as well – the equivalent of removing 500 passenger cars from the road for one year.

A Preferred Engineering Services Provider for Baltimore Gas & Electric, OpTerra was able to qualify the project for a significant financial incentive from the utility. In addition, the project was awarded a grant through the Maryland Energy Administration (MEA) Commercial-Industrial Grant Program.


Owned by City Crescent, LLC, managed by Cambridge Asset Advisors, LLC, and developed in 1992, City Crescent is a Class-A, eleven story, 334,000 square foot office building. Since its development, City Crescent has served as a catalyst for the revitalization of the west side of Baltimore City, helping to foster an environment of economic competitiveness, access to public transportation, and an increase in quality of life for those working and living in the area.

Utilizing its Professional Engineers and LEED Accredited Professionals on staff, OpTerra completed a detailed study and analysis of not only the lighting and controls systems at City Crescent, but also the intricate HVAC and mechanical systems. The solution designed by OpTerra entailed multiple measures, significantly decreasing the energy consumption and increasing tenant comfort at the all-electric building , and resulting in ENERGY STAR certification approximately one year after project implementation.

For the lighting aspect of the project, OpTerra replaced existing lighting technology throughout office space, stairways and parking garage space with high-efficiency lamps, low-power factor ballasts and occupancy controls. This retrofit will reduce lighting consumption up to 50% in some areas.

The existing Condenser Water (CW) cooled system was nearing the end of its life, inefficient, and using harmful HCFC refrigerant. OpTerra’s solution entailed the installation of two new water cooled chillers with frictionless compressors. The new system also benefits from the utilization of free cooling in shoulder months, in conjunction with airside economizers and controls.

OpTerra carefully coordinated the chiller plant installation, placing the massive new units on the top floor of the building to avoid interference with tenants and maintain the building’s attractive look and feel.

The existing Building Automation System (BAS) at City Crescent was pneumatic, requiring expensive compressed air to function. OpTerra converted the existing controls system to an open-protocol, Direct Digital Control (DDC) based BAS, eliminating simultaneous heating and cooling and achieving significant savings.