DISPARATE STANDARDS: COMPARING STANDARD DOMESTIC HOT WATER MODELING METHODS FOR MULTI-RESDENTIAL BUILDINGS
DHW (Domestic hot water) energy consumption is a
critical component in multi-family residential building
While proper modeling of DHW is essential to creating
accurate whole building energy models of multi-family
residential buildings, DHW load and energy
consumption are extremely difficult to predict, since
they are highly influenced by end-user behavior. The
existing various calculation methods, including
ASHRAE Handbooks, ASHRAE 90.1 User’s Guides,
ASPE design Handbooks, local energy codes and
LEED guidelines, have been found to result in
drastically different DHW load numbers and DHW load
profiles, which result in large discrepancies in the
analysis of DHW energy consumption. The
discrepancies beg the question of which method is most
reliable or most accurately represents actual usage in
In order to gain a better understanding of DHW load
and energy calculation in energy simulation, in this
study, different standard DHW load calculation
methods are performed and compared to actual mutifamily
residential building meter data with respect to
DHW peak demand, load profile, and energy
consumption. The factors which impact the energy
consumption calculation results are discussed.
Recommendations on appropriate calculation methods
for DHW energy modeling are made. In addition, the
impact of energy conservation measures, such as low
flow fixtures and condensing DHW boilers are
ASHRAE 1989. ANSI/ASHRAE/IESNA Standard 90.1-1989, American Society of Heating, Refrigerating and Air-Conditioning Engineers, INC.
ASHRAE 2004. ANSI/ASHRAE/IESNA Standard 90.1-2004 User’s Manual, American Society of Heating, Refrigerating and Air-Conditioning Engineers, INC.
ASHRAE 2013. ANSI/ASHRAE/IESNA Standard 90.1-2010 User’s Manual, American Society of Heating, Refrigerating and Air-Conditioning Engineers, INC.
ASHRAE 2015. ASHRAE Handbook – HVAC Applications, American Society of Heating, Refrigerating and Air - Conditioning Engineers, INC.
ASPE 2010. Plumbing Engineering Design Handbook - Volume 2 – Plumbing Systems, Amercian Society of Plumbing Engineers
ASPE 2003. Domestic Water Heating Design Manual, Amercian Society of Plumbing Engineers
CaGBC 2009. LEED Canada Reference Guide for Green Building Design and Construction 2009, Canada Green Building Council
CMHC (Canada Mortgage and Housing Corporation ) 2005. Energy and Water Consumption Load Profiles in Multi-unit Residential Buildings, Research Highlight, Techincal Seriers 05-119
Goldner, F.S. 1994a. Energy Use and Domestic Hot Water Consumption: Final Report – Phase I. Report 94-19, New York State Energy Research and Development Authority, Albany, NY.
Goldner, F.S. 1994b. DHW System Sizing Criteria for Mutifamily Buildings, ASHRAE Transactions 100(1):963-977
MNECB 1997. Model National Energy Code of Canada for Buildings, Canadian Commision on Building and Fire Codes, National Research Council of Canada Werden, R.G., and Spielbogel, L.G. 1969a. Sizing of Service Water Heating Equipment in Commercial and Institutional Buildings, Part I, ASHRAE Transactions 75(I):81
Werden, R.G., and Spielbogel, L.G. 1969b. Sizing of Service Water Heating Equipment in Commercial and Institutional Buildings, Part II, ASHRAE Transactions 75(II):181
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