ASHRAE Journal January 1984

Religious building energy use

Analysis of consumption in the Philadelphia area shows wide variations in the amount of energy consumed and indicates the possibility of large reductions.

By Lawrence G. Spielvogel, P.E. (Member ASHRAE) and Andrew Rudin (Member ASHRAE)
Taken from : American Society of Heating, Refrigerating and Air Conditioning Engineers Journal January 1984

The non-profit Interfaith Coalition on Energy (ICE) was formed in 1980 by the Archdiocese of Philadelphia, the Philadelphia Board of Rabbis, the Philadelphia Chapter of American Jewish Committee and the Philadelphia Metropolitan Christian Council of Churches. In a pilot program in 1980, walk-through energy audits were conducted in three religious complexes. During the following year measured reductions in energy use of 14 to 19 percent were achieved.

Subsequently, the Pew Memorial Trust, a private foundation in Philadelphia, funded ICE to:
(1) accomplish energy audits in religious buildings,
(2) publish newsletters, and
(3) conduct seminars on energy conservation for the religious community.

Religious buildings have not been a target for government or private conservation programs.

Because they rely on the generosity of fewer and fewer persons each year, congregations have had little money to either hire private consultants or to perform substantial building or system modifications.
Therefore, the approach of ICE in identifying short pay-back low cost changes and improvements in these buildings is welcomed and timely.

The purpose of this article is to present and analyze measured energy consumption in existing religious buildings in the Philadelphia area based on the audits accomplished. It Is also intended to inspire the creation of similar coalitions throughout the country by showing data on energy use found in a large sample of religious buildings to serve as a point of departure and a basis for comparison.

Building characteristics

Religious buildings in the Philadelphia area average 57 years old and are of institutional grade construction with little or no insulation. The predominant heating systems are gas and oil fired steam and hot water boilers with few zones of control. Only a small portion of the buildings are totally cooled. A substantial portion of the lighting is incandescent.

Few of the buildings were found to have accomplished much in the way of energy related improvements, thus allowing frequent recommendations for cost effective, relatively inexpensive modifications that have short paybacks. However, it is common to find that the occupants of these buildings demonstrate energy consciousness by turning energy-using devices off when not needed andregularly turning down thermostats manually when buildings are not being used.

An institution is defined as one or more buildings at a single location, with at least one sanctuary. A complex is defined as more than one building at a single location, one of which is a sanctuary. All forms of energy used in each building in a complex were no always metered. Some meters, fuel tanks or boilers served more than one building. As a result, it is not possible to establish accurate measured energy use of all individual buildings in complexes.


A total of 188 buildings and complexes containing 2,052,620 square feet of floor area was audited during 1983. For the purpose of this article, 66 of these buildings which did not have all forms of energy separately metered were excluded. Included in the Appendix is a listing of measured data for 63 institutions, of which 25 consist of a single building containing a
sanctuary and 38 consist of multiple-building complexes, at least one of which houses a sanctuary. These buildings included in the Appendix contain approximately 1,070,000 square feet of floor area and serve as the data base for this analysis.

Energy data were gathered for 12 consecutive months for each form of energy in each building or complex prior to the site analysis. The building characteristics were subsequently measured, and information was gathered on up to 32 characteristics of the institution; the information was then sorted using a relational data base.

Table 1 shows the conversion factors which were used to compute the energy use. Data on climate that was experienced during the time the energy data were gathered are listed in Table 2.

(Tables 1 through 16 are available for viewing in the 6 page article, 2 megs)

Energy Costs

Table 3 shows recent energy costs for religious institutions in the Philadelphia area. The average cost of electricity is higher for non-residential buildings due to differences in utility rates and hours of use.

Table 4 is a summary of the results of the energy audits. The lowest and highest figures provide an indication of the tremendous cost ranges found in these institutions. The average religious institution in Philadelphia spent almost $23,000 annually for energy during recent years. This amounts to about 19 percent of the total institutional operating budget, or an
average of $2.42 per week for each active member family in the typical congregation. The audits predict that for the average institution an investment of $2,245 would yield energy cost savings of $5,110 during the first year, or a 22 percent reduction.

(Tables 1 through 16 are available for viewing in the 6 page article, 2 megs)

In many cases, the first cost of the modification is for materials only, with employees and volunteers supplying the labor for the installation.

Energy use by building type

Table 5 presents energy use separated by type of building. Complexes include all types of residential and non-residential buildings. Residential buildings include convents, rectories and parsonages. All other types of buildings are considered non-residential. Sanctuaries were further categorized as being primarily used for worship or having multiple uses including worship.

(Tables 1 through 16 are available for viewing in the 6 page article, 2 megs)

The residential buildings use about seven percent more energy than non-residential buildings, probably because they tend to be occupied for longer hours and at times (night) when the heating requirements are greatest.Among the non-residential buildings, those which tend to have the lowest hours of use tend to have the lowest energy use, except for sanctuaries used primarily for worship, for which no explanation is evident.

Energy use by building size …..

To read the full 6 page article in PDF Format, click on the link below:
ashrae_journal_jan_1984.pdf  (Opens in a new window, file size 2 megs)





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