A proper understanding of the functional basis of energy use in residences has been crucial in spurring energy conservation in such building stock. In commercial buildings, however, such understanding is lacking, partly because there are numerous possible HVAC system types and control strategies, and partly because the detailed algorithms available to simulate energy use in various types of HVAC systems provide little insight into identifying ways of saving energy in existing buildings. The objective of this paper is to derive closed-form steady-state functional relations for air-side cooling and heating thermal energy use for four of the most widespread HVAC system types, namely terminal reheat and dual-duct, both under constant air volume and under variable air volume operation. Expressions are derived for hourly energy use as a function of climatic variables, building characteristics, and system parameters. The effects of economizer cycle and deck reset schedules are also treated. The expressions derived could be utilized to develop functionally accurate regression models of monitored energy use for retrofit savings determination and to ascertain whether the HVAC system is operating properly, as well as for parameter estimation from either short-term or long-term monitoring and for sensitivity analyses of how various physical and operating parameters affect energy use.

1.
ASHRAE, 1985, Fundamentals, American Society of Heating, Refrigerating and Air-Conditioning Engineers, Atlanta, GA.
2.
Beck, J. V., and Arnold, K. J., 1977, Parameter Estimation in Engineering and Science, John Wiley and Sons, New York.
3.
Bevington
R.
, and
Rosenfeld
A.
,
1990
, “
Energy for Buildings and Homes
,”
Scientific American
, Sept., Vol.
263
, p.
76
76
.
4.
Claridge
D.
,
Haberl
J.
,
Turner
W.
,
O’Neal
D.
,
Heffington
W.
,
Tombari
C.
, and
Jaeger
S.
,
1991
, “
Improving Energy Conservation Retrofits with Measured Savings
,”
ASHRAE Journal
, Oct., Vol.
33
, p.
14
14
.
5.
Dhar, A., Reddy, T. A., and Claridge, D. E., 1994, “Improved Fourier Series Approach to Modeling Hourly Energy Use in Commercial Buildings,” ASME/JSME/JSES International Solar Energy Conference, Solar Engineering 1994, D. E. Klett, R. E. Hogan, and T. Tanaka, eds., San Francisco, Mar., p. 455.
6.
DOE-2, 1981, Engineers Manual, Version 2.1A, D. A. York and C. C. Cappiello, eds., Lawrence Berkeley Laboratory, Berkeley, CA.
7.
EIA, 1992, The Energy Policy Act of 1992, Public Law 102-486-October 24, 1992, Energy Information Agency, Washington, DC.
8.
Fiksel, A., Thornton, J. W., Klein, S. A., and Beckman, W. A., 1994, “Developments to the TRNSYS Simulation Program,” ASME/JSME/JSES International Solar Energy Conference, Solar Engineering 1994, D. E. Klett, R. E. Hogan, and T. Tanaka, eds., San Francisco, Mar., p. 379,
9.
Heffington, W. A., 1993, personal communication.
10.
IEA, 1983, “Annex 25: Building Optimization and Fault Diagnosis System Concept,” J. Hyvarinen and R. Kohonen, eds., International Energy Agency, Finland, Oct.
11.
Katipamula
S.
, and
Claridge
D. E.
,
1993
, “
Use of Simplified Systems Models to Measure Retrofit Savings
,”
ASME JOURNAL OF SOLAR ENERGY ENGINEERING
, ASME, Vol.
116
, p.
57
57
.
12.
Katipamula, S., Reddy, T. A., and Claridge, D. E., 1994, “Development and Application of Regression Models to Predict Cooling Energy Consumption in Large Commercial Buildings,” ASME/JSME/JSES International Solar Energy Conference, Solar Engineering 1994, D. E. Klett, R. E. Hogan, and T. Tanaka, eds., San Francisco, Mar., p. 307.
13.
Kissock, J. K., Claridge, D. E., Haberl, J. S., and Reddy, T. A., 1992, “Measuring Retrofit Savings for the Texas LoanSTAR Program: Preliminary Methodology and Results,” ASME/JSES/KSES International Solar Energy Conference, Hawaii, Mar., p. 299.
14.
Knebel, D. E., 1983, Simplified Energy Analysis Using the Modified Bin Method, American Society of Heating, Refrigerating and Air-Conditioning Engineers, Inc., Atlanta, GA.
15.
McQuiston, F. C., and Spitler, J. D., 1992, Cooling and Heating Load Calculation Manual, 2nd ed., American Society of Heating, Refrigeration and Air-Conditioning Engineers, Atlanta, GA.
16.
Liu, M., Houcek, J., Athar, A., Reddy, A., Claridge, D., and Haberl, J., 1994, “Identifying and Implementing Improved Operation and Maintenance Measures in Texas LoanSTAR Buildings,” ACEEE 1994 Summer Study on Energy Efficiency in Buildings, Vol. 5, Pacific Grove, CA, Aug-Sept., p. 153.
17.
Reddy
T. A.
,
Kissock
K.
,
Katipamula
S.
, and
Claridge
D.
,
1994
, “
An Energy Delivery Efficiency Index to Evaluate Simultaneous Heating and Cooling Effects in Large Commercial Buildings
,”
ASME JOURNAL OF SOLAR ENERGY ENGINEERING
, Vol.
116
, p.
79
79
.
18.
Ruch
D.
, and
Claridge
D. E.
,
1992
, “
A Four Parameter Change Point Model for Predicting Energy Consumption in Commercial Buildings
,”
ASME JOURNAL OF SOLAR ENERGY ENGINEERING
, Vol.
114
, p.
77
77
.
19.
Stoecker, W. F., and Jones, J. W., 1982, Refrigeration and Air Conditioning, McGraw-Hill, New York.
20.
Subbarao, K., 1988, “PSTAR-Primary and Secondary Terms Analysis and Renormalization: A Unified Approach to Building Energy Simulations and Short-Term Monitoring,” SERI/TR-254-3175, Solar Energy Research Institute, Golden, CO.
This content is only available via PDF.
You do not currently have access to this content.