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Title: Performance of Integrated Hydronic Heating Systems.

Abstract

A variety of system configurations are used in North America to meet the heating and domestic hot water needs of single-family homes. This includes, for example: warm air furnaces with electric water heaters; boilers with integrated hot water coils; and boilers with 'indirect' hot water storage tanks. Integrated hydronic systems which provide both heat and hot water are more popular only in the Northeast and mid-Atlantic regions. For those making decisions about configurations of these integrated hydronic systems, including control options, little information is available concerning the annual energy cost implications of these decisions. This report presents results of a project to use a direct load emulation approach to measure the performance of hydronic systems, develop performance curves, and to provide decision tools to consumers. This is a laboratory measurement system involving direct energy input and output measurements under different load patterns. These results are then used to develop performance correlations for specific systems that can be used to predict energy use in specific applications. A wide range of system types have been tested under this project including conventional boilers with 'tankless' internal coils for domestic hot water production, boilers with indirect external storage tanks, tank type water heaters whichmore » may also be used for space heating, condensing oil- and gas-fired systems, and systems with custom control features. It is shown that low load and idle energy losses can have a very large impact on the total annual energy use and that the potential energy savings associated with replacing old equipment with newer, high efficiency equipment with low losses at idle or low load can be in the 25% range. These savings are larger than simple combustion efficiency measurements would indicate.« less

Authors:
Publication Date:
Research Org.:
Brookhaven National Lab. (BNL), Upton, NY (United States)
Sponsoring Org.:
USDOE
OSTI Identifier:
924431
Report Number(s):
BNL-79814-2008-IR
R&D Project: 87793; 600301020; TRN: US200809%%448
DOE Contract Number:
DE-AC02-98CH10886
Resource Type:
Technical Report
Country of Publication:
United States
Language:
English
Subject:
32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATION; ENERGY ACCOUNTING; ENERGY LOSSES; HEATING SYSTEMS; HOT WATER; PERFORMANCE; SPACE HEATING; WATER HEATERS; ENERGY EFFICIENCY

Citation Formats

BUTCHER,T.A.. Performance of Integrated Hydronic Heating Systems.. United States: N. p., 2007. Web. doi:10.2172/924431.
BUTCHER,T.A.. Performance of Integrated Hydronic Heating Systems.. United States. doi:10.2172/924431.
BUTCHER,T.A.. Thu . "Performance of Integrated Hydronic Heating Systems.". United States. doi:10.2172/924431. https://www.osti.gov/servlets/purl/924431.
@article{osti_924431,
title = {Performance of Integrated Hydronic Heating Systems.},
author = {BUTCHER,T.A.},
abstractNote = {A variety of system configurations are used in North America to meet the heating and domestic hot water needs of single-family homes. This includes, for example: warm air furnaces with electric water heaters; boilers with integrated hot water coils; and boilers with 'indirect' hot water storage tanks. Integrated hydronic systems which provide both heat and hot water are more popular only in the Northeast and mid-Atlantic regions. For those making decisions about configurations of these integrated hydronic systems, including control options, little information is available concerning the annual energy cost implications of these decisions. This report presents results of a project to use a direct load emulation approach to measure the performance of hydronic systems, develop performance curves, and to provide decision tools to consumers. This is a laboratory measurement system involving direct energy input and output measurements under different load patterns. These results are then used to develop performance correlations for specific systems that can be used to predict energy use in specific applications. A wide range of system types have been tested under this project including conventional boilers with 'tankless' internal coils for domestic hot water production, boilers with indirect external storage tanks, tank type water heaters which may also be used for space heating, condensing oil- and gas-fired systems, and systems with custom control features. It is shown that low load and idle energy losses can have a very large impact on the total annual energy use and that the potential energy savings associated with replacing old equipment with newer, high efficiency equipment with low losses at idle or low load can be in the 25% range. These savings are larger than simple combustion efficiency measurements would indicate.},
doi = {10.2172/924431},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Thu Dec 20 00:00:00 EST 2007},
month = {Thu Dec 20 00:00:00 EST 2007}
}

Technical Report:

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  • This document is intended to serve as a basis for the US Department of Energy's (DOE's) multilayer plan for research on thermal distribution and utilization (TDU). In this document, the areas of research included under the heading of thermal distribution and utilization are defined, their benefits are shown, and a ten-year program of research is recommended. Part I of the Plan concentrates on forced-air thermal distribution systems in residences and small commercial buildings. Part II covers hydronic and radiant systems. TDU research refers to the study of the phenomena associated with the transport of heat and cooling effect from themore » central heating or cooling equipment via pipes or ductwork to the building spaces to be comfort conditioned. The intent of the research is to maximize the thermal performance of buildings, where thermal performance is defined as the ratio of person-hours of thermal comfort provided, divided by the energy required to provide that comfort. TDU research will improve thermal performance by reducing the thermal losses occurring in ductwork, and by prviding acceptable means of zoned heating and cooling of building spaces. 18 figs., 7 tabs.« less
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