Session: 16-01: Poster Presentations

Paper Number: 130706

130706 - Energy Savings and Feasibility Analysis of Heat Pump Retrofits for Midrise Multifamily Buildings in New York City 

Abstract: 

Motivated by reducing impacts of climate change due to greenhouse gas emissions, many dense urban cites throughout the United States have set into law ambitions decarbonization policies that will require buildings to replace fossil fuel space and water heating systems with electric powered alternatives. In many cities, especially in the northeast, fossil fuel space and water heating are used in a vast majority of buildings and significantly contribute to citywide carbon emissions. In New York City (NYC), it is estimated that over 40 percent of citywide emissions come from space heating and water heating systems that run on fossil fuels. Amongst the most challenging building types for cities to retrofit are multifamily buildings due to space constraints, the coordination required surrounding the tenants of the building, the high replacement cost, and the conditions of the existing infrastructure.

NYC will undoubtedly be one of the most challenging cities to decarbonize, due to its aging building stock and having the highest population density in the United States. Most buildings have old, inefficient steam boilers that remain in place well beyond their expected life due to the challenges associated with retrofitting. Yet in September 2014, NYC established a goal of reducing 80 percent of carbon emissions by 2050 (from 2005 levels), with an interim target to reduce 40 percent of carbon emissions by 2030. Subsequent legislation is set to go into effect that will fine building owners for exceeding carbon emission limits. As a result, buildings owners will soon be forced to decarbonize their space and water heating systems to avoid these fines.       

The main objective of this study is to explore various air source heat pump (ASHP) technologies and configurations that could feasibly replace fossil fuel heating and water heating systems for NYC midrise multifamily buildings. Using the use case of an existing building that recently partnered with the Association of Energy Affordability (AEA) to replace their fossil fuel heating and water heating systems with heat pumps, the report couples building energy modeling (BEM) analysis and empirical data from completed projects to assess energy savings, cost savings, and installation feasibility of retrofitting existing systems with market-ready technologies. Three ASHP technologies were selected for space heating: variable refrigerant flow (VRF) heat pumps, air-to-water heat pumps, and packaged terminal heat pumps. This report also addresses retrofitting water heating systems with heat pump technology. Qualitative and quantitative data collected by AEA from recently completed multifamily retrofit projects will be used supplement the BEM and feasibility analysis to help guide future retrofits. Preliminary results of the BEM analysis indicate that the three space heating ASHPs offer comparable energy savings but the feasibility of each technology varies greatly depending on when the building was constructed and the existing configuration of the heating and water heating systems. The recently completed projects by AEA reveal that older buildings with central steam heating systems, which is found in most midrise multifamily buildings in NYC, favor packaged terminal heat pumps in terms of feasibility and cost effectiveness.

Presenting Author: Sam Chussid The City College of New York

Presenting Author Biography: Sam is a part-time, graduate student in the Mechanical Engineering Department at The City College of New York, focusing on building technology and sustainable energy. He also works at Energy Solutions as a Senior Engineer, implementing energy efficiency incentive programs and supporting decolonization policy.

Authors:

Sam Chussid The City College of New York
Jorge Gonzalez-Cruz University at Albany