Climate Change & Environmental Services (CCES) led a team of energy specialists in performing an energy audit and retro-commissioning study for two large apartment buildings, part of the East River Housing complex on the Lower East Side of Manhattan. The effort was done to comply with New York City’s Local Law 87, requiring all large buildings to perform an ASHRAE Level II energy audit and a retro-commissioning study once every 10 years.

An energy audit was performed for two 20-story apartment buildings and their base heating system. Data from the boiler house was collected to estimate how much steam and domestic hot water was used by the apartment buildings in question, and from that, how much natural gas and No. 2 fuel oil was used annually. Two years of electricity bills were then evaluated from common functions (lobby and hall lighting, elevators, pumps) and aggregated bills for cumulative electricity use by residents. A month-by-month energy profile for a recent year was determined for both electricity and fuel usage.

Energy conservation measures (ECMs) were then determined, strategies that if implemented would result in energy cost savings. Specialists in lighting and elevator motors were brought on to the team to provide specific insight. These areas, although functioning well, were evaluated for potential upgrades to more energy efficient equipment to reduce usage, demand, and costs. For each ECM strategy, estimated upfront and O&M costs, energy savings (kWh or therms of natural gas), cost savings, and simple payback were estimated. Local Law 87 does not require a building manager to implement any ECM; only to consider it. Several were found for the complex.

A retro-commissioning (RCx) study was performed for the two buildings. Local Law 87 contains 25 criteria that must be tested for RCx. For apartment buildings like these, the most important (and time-consuming) item to consider is steam trap testing. At least 10% of all representative steam traps must be tested to determine whether steam is entering the condensate line. If less than 90% of these 10% pass, then all steam traps must be tested. Even testing 10% of steam traps is problematic, as that means likely entering people’s apartments. If less than 90% pass, then it becomes very time-consuming and troublesome. Therefore, in preparation for such a step, it is a good idea to perform pre-testing of selected steam traps and/or upgrading of old units. This complex has an informal pre-testing process. To comply with Local Law 87, they made it a more formal process, including cataloging all steam traps and ensuring they test a representative sample regularly and replace when necessary. Building management saw this as a good process, to stay ahead of the curve in terms of heat delivery.

Not meeting any of the 25 criteria is considered a “deficiency” by Local Law 87, generally low/no cost fixes or upgrades that will likely save energy or prevent damage. Local Law 87 does require all labelled “deficiencies” to be addressed and verified by the RCx professional. Several deficiencies were detected and building management did successfully address them.

CCES has the experts to help you perform an energy audit or retro-commissioning study to comply with Local Law 87 or to find ways to reduce energy costs and ensure that the equipment you paid good money for are operating optimally. We can help you get the best use of your energy systems, to ensure you get your money’s worth, and make your tenants more comfortable. Contact us today at karell@CCESworld.com or at 914-584-6720.