NBSIR 78-1568

Economic Analysis of the Norris Cotton Federal Office Building

Phillip T. Chen

Center for Building Technology

National Engineering Laboratory

National Bureau of Standards

U.S. Department of Commerce

Washington, D.C. 20234

Sponsored by:

The Department of Energy

Washington, D.C. 20461

NOVEMBER 1978

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ftaKonal ffnreag of Sf3R<f&rd* MAY t 4

NBSIR 78-1568

ECONOMIC ANALYSIS OF THE NORRIS COTTON

FEDERAL OFFICE BUILDING

Phillip T. Chen

Building Economics and Regulatory Technology Division

Center for Building Technology

National Engineering Laboratory

National Bureau of Standards

Washington, D.C. 20234

November 1978

Sponsored by:

The Department of Energy

Washington, D.C. 20461

U.S. DEPARTMENT OF COMMERCE, Juanita M. Kreps, Secretary

Dr. Sidney Harman, Under Secretary

'

Jordan J. Baruch. Assistant Secretary for Science and Technoiogy

NATIONAL BUREAU OF STANDARDS, Ernest Ambler, Director
5.,t ; ,::.:,.v,.'il^.!''ii|jji|^*; r„ v ; .: .;!?
PREFACE

This study was conducted by the Applied Economics Program of the

National Bureau of Standards for the Department of Energy to demonstrate

how economic analysis can be applied to the post-occupancy evaluation of

the Norris Cotton Federal Office Building, owned and operated by the

General Services Administration as an energy conserving building.

Drs. Harold E. Marshall and Stephen F. Weber and Mr. Robert E. Chapman

provided reviews of the economic aspects of this paper. Drs. James E.

Hill and Stanley T. Liu and Mr. Thomas E. Richtmyer furnished thermal

engineering data. Mr. G. G. Wells reviewed the architectural and cost

aspects of this study. Mr. Gerald K. Farrington provided building operation and energy consumption data. Ms. Kimberly A. Hockenbery made cost

calculations. The author wishes to express his appreciation to the above

persons without whose help this study could not have been completed.

i I i
ABSTRACT

The Norris Cotton Federal Office Building in Manchester, New Hampshire, has been constructed and occupied by the General Services Administration to demonstrate energy conservation techniques in the design and

operation of a contemporary office building. This post occupancy economic evaluation conducted by the National Bureau of Standards shows

that additional construction costs incurred in order to reduce the

energy consumption of the building are adequately offset by the present

value of the resulting annual energy savings. In the economic model,

the actual construction cost and energy consumption of the constructed

building are compared with the estimated construction cost and energy

consumption of a hypothetical equivalent conventional building. The

present value costs of the two buildings are calculated for each year

during a 40-year study period.

Keywords: Building design; construction cost estimation; discounted

payback period; economic analysis; economic evaluation;

energy conservation; life-cyle costing; present value

analysis

iv
TABLE OF CONTENTS

Page

PREFACE ill

ABSTRACT Iv

LIST OF TABLES AND FIGURES vi

SI CONVERSION UNITS vii

1.0 INTRODUCTION 1 1.1 Purpose 2 1.2 Scope and Approach 2 1.3 Organization 3

2.0 CONSTRUCTION COST AND ENERGY CONSUMPTION 4

2.1 Equivalent Conventional Building (ECB) 4

2.2 Building Construction Costs 5 2.3 Annual Energy Consumption 5

3.0 ECONOMIC EVALUATION 10

3.1 Life-Cycle Cost Model 10

3.2 Data Assumptions 11

3.3 Economic Comparison 11

4.0 SUMMARY AND RECOMMENDATION FOR FURTHER RESEARCH 21

4 . 1 Summa ry 21

4.2 Recommendation for Further Research 21

APPENDIX A BUILDING DESIGN AND COST DATA A-1

APPENDIX B ENERGY USAGE AND PRICE DATA B-1

APPENDIX C YEAR-BY-YEAR PRESENT VALUE COSTS C-1

REFERENCES '. D-1

V
LIST OF TABLES

PAGE

2.1 BUILDING CONSTRUCTION COSTS IN 1976 DOLLARS 6

2.2 ANNUAL ENERGY CONSUMPTION FOR NORRIS COTTON FEDERAL OFFICE

BUILDING (NCFOB) IN 10^ BTU AND 1977 DOLLARS 7

2.3 ANNUAL ENERGY CONSUMPTION FOR ECB IN 10^ BTU AND 1977 DOLLARS. 9

3.1 ESTIMATED ANNUAL PERCENTAGE INCREASE IN REAL ENERGY PRICES 12

3.2 PRESENT VALUE COSTS AND CALCULATION OF PRESENT VALUE SAVINGS

($1,000) 13

3.3 PRESENT VALUE COSTS AND SAVINGS WITH MODIFIED ENERGY

CONSUMPTION FOR ECB ($1,000) 15

LIST OF FIGURES

3.1 CASE I Present Value Cost Vs. Lifespan for NCFOB & ECB 17

3.2 CASE II Present Value Cost Vs. Lifespan for NCFOB & ECB 18

3.3 CASE III Present Value Cost Vs. Lifespan for NCFOB & ECB 19

3.4 CASE IV Present Value Cost Vs. Lifespan for NCFOB & ECB 20

VI
SI Conversion Units

In view of the present accepted practice in this country for building

technology, common U.S. units of measurement have been used throughout

this publication. In recognition of the position of the United States

as a signatory to the General Conference of Weights and Measures, which

gave official status to the metric SI system of units in 1960, appropriate conversion factors have been provided in the table below. The

reader interested in making further use of the coherent system of Si

units is referred to:

NBS SP330, 1972 Edition, "The International System of Units"

E380-72 ASTM Metric Practice Guide (American National Standard

Z210. 1)

Vll
Table of Conversion Factors in iletric (S.L.) dnits

Physical

Quant ity

(and symbol

used in paper)

To convert

1 r om to mu Itiply by

Length X inch meter 2.54* X 10”3

foot m 3.048* X 10 ) Area 2 inch m^ 6.4516 X 10

f oot^ m^ 9.290 X

10"-^

Volume 3 inch m3 1.639 X 10“3

foot^ m3 2.832 X 10“3

Temperature Fahrenheit Celsius ^C

" (tp-32)/1.8)

Temperature Fa hrenheit Kelvin K = (Atp)/1.8

difference

Pressure inch Hg (60°F) newton/ m^ 3.377 X 103

Mass Ibm kg . 4.536 X 10 ^ Mass/unit area M Ibm/ f t^ kg/ m3 4.882

Moisture content Ibm/f t^week kg/m^s - 8.073 X 10"^

rate

De ns i ty t Ibm/ f t^ kg/ m3 1.602 X 10^

Thermal con- k Btu/hr ft^(F/inch) W 1.442 X 10“^

ductivity mk

U-value Btu/hrf t”^°F w 5.678

m^K

Thermal resis- R F/(Btu/hr ft^) K/(W/m3) 1.761 X 10“^

tance

Heat flow Btu/hr ft^ W/ m3 3.155

Water vapor:

permeability P grain kgm/Na 1.457 X 10~^3

hr f t^(in.Hg/in.

)

permeance P,P grain kg/Na 5.738 X 10"^^

hr ft^(in.Hg)

(perm)

* Exact value; others are rounded to fourth place.

vlii
1.0 INTRODUCTION

As part of its response to the energy crisis, the General Services

Administration (GSA), in 1972, designated the proposed Federal Office

Building in Manchester, New Hampshire, as an energy conservation demonstration project to evaluate energy conservation techniques in the

design and operation of a contemporary office building.

The GSA subsequently appointed a design team to incorporate energy conservation techniques in the building. This team consisted of the GSA

project administrator and staff from the Central and Region I Offices;

Dubin Bloome Associates, Energy Conservation Consultants; Isaak and

Isaak, Architects; Rose, Goldberg and Associates, Structural Consultants; Richard D. Kimball Co., Mechanical Consultants; and the National

Bureau of Standards (NBS), design and evaluation consultants.

With the aid of the computerized National Bureau of Standards Load

Determination Programs (NBSLD)^, the effects of various building design

alternatives on the annual energy consumption of the proposed building

were evaluated by NBS. The NBS also assisted the Mechanical Consultant

in sizing various components of the heating ventilation and air conditioning HVAC systems. Furthermore, the NBS drafted specifications to

purchase a computerized energy monitoring and control system to measure

the energy consumption and performance data.

In brief, the design team selected for the proposed Federal building

the following opportunities for energy conservation: building envelope

design including doors, windows, mass and Insulation; various designs;

solar energy for space heating and cooling; and various lighting systems.^ Construction of the building began in December 1974 and was com- pleted in August 1976. Fifteen Federal agencies serving the region now occupy the building, which has subsequently been designated as the

Norris Cotton Federal Office Building.

In addition to its role in the building design and energy monitoring,

NBS was also requested by the then Energy Research and Development

^ Tamami Kusuda, James E. Hill, Stanley T. Liu, James P. Barnett and

John W. Bean, Pre-Design Analysis of Energy Conservation Options for

a Multi-Story Demonstration Office Building , U.S. Department of

Commerce, National Bureau of Standards, Building Science Series 78,

2 For a detailed description of the specific energy conservation features

selected for the building, see Nicholas Isaak and Andrew Isaak, Designing an Energy-Efficient Building; A Case Study , General Services

Administration, September 1975.

November 1975.

1
Administration (ERDA) and now the Department of Energy (DOE) to make

post-occupancy evaluations on the economic, engineering and user acceptance aspects of the energy conservation technqiues. This report is

written to fulfill the requirement of an economic evaluation after

the building is occupied.

1.1 PURPOSE

The purpose of this report is to present the results of an analysis of

the cost effectiveness of the investments made in the energy conserving

techniques for the Norris Cotton Federal Office Building in Manchester,

N.H. This analysis addressed the question of whether the additional construction costs incurred in order to reduce the energy consumption of

the building are adequately offset by the value of the resulting annual

energy savings.

1.2 SCOPE AND APPROACH

In this report, the construction costs of the Norris Cotton Federal

Office Building (NCFOB) and an Equivalent Conventional Building (ECB) are combined with the corresponding annual energy consumption in a present value format of a maximum lifespan of 40 years. The ECB was designed in such a way that its size and shape, quality of material

and construction, and occupancy requirements would be approximately

equal to those of the NCFOB. The life-cycle costs resulting from initial

construction and annual energy use are calculated for both buildings

and serve as the basis of the economic evaluation.

Since the computerized energy monitoring and control system did not

become operational until December 1977, detailed energy consumption and

corresponding operating efficiencies of the individual energy conserving

features could not be measured at this time. Therefore, only the

monthly energy consumption data as reported by the utility companies

for the past year are used in conjunction with the actual construction

cost of NCFOB to present the life-cycle cost of the building as a whole. In accordance with the GSA Design Handbook of 1969, the building

costs and yearly energy consumption for the ECB are estimated. These

estimates are compared and validated with data compiled by GSA.

For the past year, the NCFOB has been operated and maintained by GSA

personnel as well as the construction contractors who have been, from

time to time, correcting the defects and furnishing the omissions in the

building. Therefore, no meaningful data on the non-energy operation and

maintenance are accurate enough to be included in the economic analysis

at this time. This report includes only the total building construction

costs and yearly energy costs of the NCFOB and ECB in the economic evaluation. Economic evaluations involving other variables are suggested in

Section 4.0 as future research efforts.

2
1.3 ORGANIZATION

The remainder of this report is divided into the following sections and

appendices

Section 2.0 describes the physical attributes, the costing method and

construction costs for both the NCFOB and ECB. The methods of calculating annual energy consumption for both the NCFOB and ECB are also

described

Section 3.0 contains the economic evaluation of both NCFOB and ECB. A

life-cycle cost model is developed here using present worth analysis of

the building investment cost and energy cost for a lifespan of up to 40

years. This model is used to obtain the present values of both NCFOB

and ECB costs, based on (reasonable) upper and lower limits of energy

use, energy price increases and lifespans.

Section 4.0 summarizes the findings of the economic analysis for the

NCFOB. Recommendations are made for conducting further research such as

the inclusion of operation and maintenance costs in the life-cycle model

and performing economic analyses of those individual energy-conserving

features which permit independent evaluation.

The appendices include the detailed listings of all construction cost,

energy usage and price data and the year-to-year present value costs for

both the NCFOB and ECB.

3
2.0

CONSTRUCTION COST AND ENERGY CONSUMPTION

Two kinds of data, namely construction cost and energy consumption, are developed in this section. Preceding the development of construction

cost and energy consumption data, the selection of the ECB suitable for

the economic comparison is required. The procedure for choosing a design for the ECB is as follows.

2.1

ECB SELECTION

A brief description of the NCFOB is needed in order to understand

how the ECB is selected.

2.1.1 NCFOB Description

The NCFOB was designed and constructed with two levels for underground

parking, seven office floors, and a mechanical house. The typical office

floor is 130 feet x 110 feet in size. The entire building has an area

of approximately 176,000 gross square feet.

In order to reduce heat loss through the exterior surfaces, the building

is shaped like a cube from the second through the seventh floors. First

floor area is extended beyond the general cube to provide for additional

ground floor space. The exterior surfaces are more massive than that of

conventional buildings. There is also less window area and thicker insulation provided for the exterior surfaces in this building. Energy con- serving mechanical and electrical systems are provided in the building.

Part of Appendix A is devoted to presenting more specific details of the

design requirements for the NCFOB.

2.1.2 ECB Design Requirements

In 1976, the architectural consulting firm of Isaak and Isaak in Manchester, New Hampshire, was contracted by the NBS to develop a comparable

design and corresponding construction cost for the ECB. Issak and Isaak

had done an early version of the NCFOB. Following is a list of general

criteria used for the selection of the ECB design.

1. That the total assignable area be identical to that in the NCFOB.

2. That the auxiliary spaces such as parking and maintenance work

spaces be of the same size as the NCFOB.

3. That the construction site be the same as the NCFOB.

4. That the conventional design be in compliance with GSA Design

Handbooks and acceptable local practices.

5. That the architectural and engineering quality be the same as the NCFOB.

6. That the period of construction be the same as the NCFOB, from

May 1, 1974 to August 24, 1976.

A design for the ECB was selected by Isaak and Isaak and accepted by the

NBS. The specific design requirements are described in Appendix A.
2.2 BUILDING CONSTRUCTION COSTS

The construction costs developed here for the NCFOB and ECB do not

include the following cost items: Site acquisition cost; architecture

and engineering design fees^; furniture and furnishing cost; and relocation cost. These cost items are excluded from the economic comparison

because they are generally considered to be equal for both buildings and

therefore will not affect the outcome of the cost comparison of both

buildings. The construction costs are described as follows.

The NCFOB construction cost represents the original contract price in the

Spring of 1974 to be fully paid for in the Fall of 1976. All contract

change orders made during the construction period were adjusted so that

the resulting figures represent the dollar values as of the start of con- struction. The sum of the original contract price and the adjusted

change order prices is used here as the total NCFOB construction cost

incurred at the end of 1976.

The ECB construction cost developed here was originally estimated by

Isaak and Isaak and subsequently modified by the NBS and reviewed by the

GSA. A major modification is the change from a six story building to a seven story building to provide the same height for both buildings.

Based on the cost data contained in Appendix A, the resulting information

suitable for the economic evaluation is shown in Table 2.1.

2.3 ANNUAL ENERGY CONSUMPTION

Two distinct estimates of the annual energy consumption for each of the

two buildings were made. The detailed data on which these estimates were made can be found in Appendix B.

2.3.1 Energy Consumption for NCFOB

For the NCFOB the predicted level of energy consumption shown in Table

2.2 was computed by the NBSLD program using 1962 weather data.^

^ The design fees for the NCFOB are considerably larger than those for

the ECB at this time. It is expected, however, that by sharing design

methods in professional publications, the design fees for energy conservation buildings eventually will be equal to those for the conventional

buildings

2 The monthly average temperatures for 1962 were very close to the thirty

year norm values for Manchester, N.H. See Tamami Kusuda, James E. Hill,

Stanley T. Liu, James P. Barnett and John W. Bean, Pre-Design Analysis of

Energy Conservation Options for a Multi-story Demonstration Office Building, U.S. Department of Commerce, National Bureau of Standards, Building

Science Series 78, November 1975.

5
Table 2.1

Building Construction Costs in 1976 Dollars

Building Elements

NCFOB

Buildings

ECB

Architectural/ Structural $6,147,122 $5,706,361

Mechanical 1,195,731 944,028

Electrical 576,181 698,698

Subtotal 7,919,034 7,349,087

GC Overhead/Profit 601,847 558,531

TOTAL 8,520,881 7,907,620

Less Extras For Non-building Items^ -285,765 None

Comparable Cost $8,235,116 $7,907,620

^ This figure represents the "Demonstration" items as explained in

Appendix A.

6
Table 2.2

Annual Energy Consumption for NCFOB in 10^ BTU and 1977 Dollars

Energy Type

Predicted Level

for 1962 Weather Data Actual Level for 1977

10^ BTU 1977 Dollars^ 10^ BTU 1977 Dollars^

Natural gas 2.290 $13,900 2.421 $14,695

Fuel oil 0 0 0.801 2,339

Electricity 3.886 40,298 5.465 56,672

TOTAL 6.176 $54,198 8.687 $73,706

^ See Appendix B for detailed energy consumption data and prices for

various energy types.

7
The actual level of energy consumption was calculated from the monthly

utility bills actually paid in 1977.

The actual energy usage in 1977 is 40.7 percent higher than the predicted level for 1962. This 40.7 percent increase may be traced to the

difference in weather conditions between 1962 and 1977, the requirement

for equipment shake-down operations during the first year of occupancy

and other non-weather factors which might include the effective insulation value and infiltration value of the building envelop and the operating efficiency of this building equipment.

While the actual energy usage in 1977 is 40.7 percent higher than the

predicted level in 1962, the dollar value of the actual energy use in

1977 is 36 percent more than the predicted level in 1962. This apparent

discrepancy between 36 and 40.7 percent is caused by the fact that in

1977, about 9 percent of the total energy used was supplied by fuel oil,

the unit price of which (cost per million BTU) is less than one half of

that for the natural gas. Consequently this unit price differential

between fuel oil and natural gas reduces the effective increase from 40.7

to 36 percent.

2.3.2 Energy Consumption for ECB

For the ECB the predicted level of energy consumption shown in Table 2.3 was computed by the NBSLD program using 1962 weather data. To correct

for the difference in weather conditions between 1977 and 1962, the

adjusted level of energy consumption is shown in Table 2.3 to reflect a

10 percent increase^ of energy consumption from the predicted level.

The annual energy costs are assumed to accrue at the end of the year.

The construction cost and building energy consumption data in this sec- tion will be used for the economic evaluation presented in Section 3.0.

^ A 10 percent increase of energy consumption was selected because of

the effect of the 8209 degree-days recorded for 1977 over the 7586

degree-days recorded for 1962. This increase of degree-days is

equivalent to a 10% increase in energy use based on the average

response of similar buildings studied by the Building Owners and

Managers Association (BOMA) for 91 conventional office buildings.

8
Table 2.3

Annual Energy Consumption for ECB in 10 9 BTU and Dollars

Energy Type

Predicted Level

for 1962 Weather Data Adjusted Level for 1977

10^ BTU 1977 Dollars^ 10^ BTU 1977 Dollars^

Natural Gas

Fuel Oil

4.983

0

$ 30,247

0

5.481

o'^

$ 33,270

ob

Electricity 7.277 75,462 8.005 83,012

TOTAL 12.260 $105,709 13.486 $116,281

^ See Appendix B

various energy

for detailed

types

energy consumption data and prices for

^ Since fuel oil is the standby energy type for heating and is intended

to be used intermittently and without any planned frequency, the annual

fuel oil consumption for the adjusted level in 1977 is assumed to be zero. This assumption tends to increase the total dollar value of the

energy consumption for ECB when comparing with the actual level for

NCFOB in 1977 listed in Table 2.2.

9
3.0 ECONOMIC EVALUATION

The comparable building cost and energy consumption data presented in the

preceding section will be combined here to form the building life-cycle

costs for owning and operating the NCFOB and ECB. These building lifecycle costs will be used for the economic evaluation.

3.1 LIFE-CYCLE COST MODEL

There are several methods to express the combined cost of an initial

investment and associated recurring costs of energy consumption, operation, and maintenance of a building. One method is to transform the

initial investment cost into an equivalent yearly uniform capital recovery payment over the life and then combine this yearly payment with the

corresponding recurring costs associated with operation, maintenance and

energy consumption over the life of the building. Another method is to

transform both the initial building investment cost and the recurring

costs to a single capital recovery amount occurring at the end of the

lifespan. The third method is to bring the stream of recurring costs

back to the same period in which the initial building investment was made and then combine these transformed recurring costs with the initial

investment to arrive at the present value cost of owning and operating

a building throughout its life. This present value cost method will be

used for the economic evaluation of both buildings. Formula 3.1 is the

general expression used to obtain present value costs over a building

lifetime

L

PVC = C + E (1+D)"^(E^+M^) - (1+D)"^*S , (3.1)

i=i

where

PVC = Present value cost

C = Construction cost

D = Discount rate

E^ = Annual energy cost in period i

M^ = Annual operation and maintenance cost (excluding energy cost)

L = Lifespan of the building in years

S = Salvage value at the end of lifespan

For the first 12 months since the completion of the building, both the

building contractors and the GSA personnel have been jointly responsible

for the building operation including the start-up and the adjustment of

building equipment. With the exception of energy cost, no meaningful

physical and cost data for building operation and maintenance have yet

been collected. Until such meaningful operation and maintenance data

1 Generally, the building contractors will correct the defects in con- struction and adjust the building equipment to comply with the original design during the warranty period.

10
become available, it is not unreasonable to assume that these costs would

be approximately equal for both buildings.

Similarly, for practical purposes the salvage values for the NCFOB and

ECB are considered equal and negligible, given the relatively long

expected life of a building. Therefore, Formula 3.1 can be simplified to

L

PVC = C + 2 (1+D)"^*E^ (3.2)

i=l

Formula 3.2 will be used for the economic evaluation in this report.

3.2 DATA ASSUMPTIONS

Derived in the previous section, the specific data used here for calculations are the building construction costs shown in Table 2.1 and the

annual energy consumption listed in Tables 2.2 and 2.3.

In order to obtain estimates of the annual energy price Increases for

Manchester, New Hampshire, the Environment and Energy Branch in the Central Office of GSA was consulted.^ The GSA energy price increases for

the next 40 years depicted in Table 3.1 are the product of this consultation, Also, the energy price increases in the New England Region as forecasted by the Federal Energy Administration^ are shown as the FEA

price increases in Table 3.1.

The discount rate, D, required for the calculation in Formula 3.2, is 10

percent throughout the economic evaluation in compliance with 0MB Circu-

;ar No. A-94, Revised, March 27, 1972.

3.3 ECONOMIC COMPARISON

Based on the construction costs listed in Table 2.1, energy consumption

data listed in Tables 2.2 and 2.3, annual energy price increases listed

in Table 3.1 and the discount rate of 10 percent, present value costs

are calculated with Formula 3.2. The results for the NCFOB and the ECB are shown in Table 3.2.

The present value of savings listed in Table 3,2 are the differences

between the present value cost of the ECB and the NCFOB. The range of

present value savings represents the cost effectiveness of the energy

conservation investment made in the NCFOB, when measured with the actual

(or adjusted) and predicted energy consumption levels and the GSA and

FEA energy price increases

G. Wells, Chief of the Environment & Energy Branch, Public Building

Series, GSA, was particularly helpful in this regard.

"Energy Audit Procedure; Proposed Rules and Hearing," Federal Regis- ter, Vol. 42, No. 73, April 15, 1977.

11

2
Table 3.1

Estimated Annual Percentage Increases in Real Energy Prices

Annual Energy Price Increase (%)

Period Type of Energy Probable^ Low^

1978 Natural gas 16 3.62

through Fuel oil 8 1.20

1980 Electricity 16 0.38

1981 Natural gas 6 3.62

through Fuel oil 4 1.20

1990 Electricity 6 0.38

1991 Natural gas 6 0

through Fuel oil 4 0

2016 Electricity 6 0

^ Estimates of the GSA Environmental and Energy Branch for the Manchester

N.H. area.

^ Estimates for the New England Region, published by FEA, "Energy Audit

Procedure

,

Proposed Rules and Hearing

,

Federal Register Vol. 42, No.

73, April 15, 1977.

12
Table 3.2

Present Value Costs and Calculation of Present Value Savings ($1000)

Lifespan and energy price increase

40 year 20 year

GSA FEA GSA FGA

Energy Price Energy Price Energy Price Energy Price

Increase Increase Increase Increase

Adjusted or ECB $10,787 $9,165 $9,836 $8,988

actual

Energy NCFOB 10,059 9,021 9,457 8,911

Consumption

1977

Saving^ 728 144 379 77

Predicted ECB 10,524 9,050 9,660 8,889

Energy NCFOB 9,577 8,816 9,134 8,735

Consumption

1962

Saving^ 947 234 526 154

^ Present value savings of the NCFOB over the ECB for the given lifetime.

13
Several noteworthy conclusions can be drawn from an examination of Table

3.2. Most importantly, the present value savings under all sets of

assumptions are positive. These positive present value savings indicate

that the additional investment in energy conservation in the NCFOB is

more than compensated by the value of the energy savings over the 40 year

and 20 year lifespans assumed. In other words, the NCFOB is economically

more attractive than the ECB for all cases studied.

Another result is that the present value savings under all four cases assuming adjusted and actual (1977) energy consumptions are lower in

value than the corresponding savings calculated for the predicted (1962)

in energy consumptions. This anomaly has arisen because the values of

the 1977 energy consumption for the ECB and NCFOB do not represent an equal percentage increase over the corresponding 1962 consumption values.

As stated in Section 2.0, the dollar value of the actual energy used in

the NCFOB was 36 percent greater than that of the consumption calculated

for the 1962 base year while the 1977 energy consumption estimated for

the ECB is only 10 percent more than that of the 1962 base year when

weather differences only are taken into account. One way to eliminate

this anomaly is to increase the estimated 1977 energy expenditures for

the ECB to 36 percent above that which was calculated by the NBSLD for

the 1962 base year. The results of this modification are presented in

Table 3.3.

A comparison of Table 3.3 with Table 3.2 reveals that the modification

of the energy consumption for ECB makes the present value savings greater

for the actual energy consumption case than for the low consumption case,

as one would expect.

Another important result in Table 3.2 is that the present value savings

rendered by the NCFOB are $947,000 in 40 years and $526,000 in 20 years

under the most probable set of assumptions. These assumptions seem to

be the most reasonable because the 1962 weather data year is a more representative one to base the life-cycle cost analysis on than that of

1977.^ Furthermore, the computer analysis performed for both the NCFOB

and ECB with 1962 weather data are based on the same assumptions included

in the NBSLD calculations. In contrast, the 1977 analysis is based on

the actual energy consumption for the NCFOB but is forced to depend on

the computer calculations of energy consumption for the ECB.

Table 3.2 also indicates that for a 40 year lifespan, there is a low present value saving of $234,000 for the FEA energy price increases and a high present value saving of $947,000 for the GSA energy price increases.

This result fulfills the expectation that for this NCFOB, the present

value saving becomes larger, the faster energy prices rise. Also as expected. Table 3.2 indicates that for the NCFOB, the longer the lifespan

chosen for evaluation, the bigger the present value saving accumulated

over that life.

As noted above the monthly average temperatures in 1962

close to thirty year norm values for Manchester, N.H.

14

were very

1
Table 3.3

Present Value Costs and Savings with Modified

Energy Consumption for ECB ($1000)

Lifespan and energy price increase

40 year 20 year

GSA

Energy Price

Increase

FEA

Energy Price

Increase

GSA

Energy Price

Increase

FEA

Energy Price

Increase

ECB^ $11,466 $9,462 $10,291 $9,243

NCFOB 10,059 9,021 9,457 8,911

Saving^ 1,407 441 834 332

^ Present value costs for ECB assuming energy consumption 36 percent

greater than estimated for the 1962 base year.

^ Present value savings of the NCFOB over the ECB for the given lifetime.

15
In addition to the present value saving, it is possible to calculate the

discounted payback period for the additional investment made on the

energy conserving features of the NCFOB. The discounted payback period

is defined as the number of years required for the additional investment

in a building to be fully paid for with the present value savings produced by the energy conservation features, taking into account the time

value of money. ^ The discounted payback periods, 6.4 years, 9.7 years,

7.8 years and 12.8 years, are shown in Figures 3.1 through 3.4 for the

energy conservation investment made in the NCFOB compared with the ECB

under the four sets of assumptions conserning the level of energy con- sumption and energy price increases. The present value savings of the

NCFOB over the ECB for all given liftimes of up to 40 years can also be

determined by measuring the distance between the two curves shown on each

of the four figures.

The discounted payback for this type of economic analysis is calculated

by finding that lifespan for which the present value costs of the NCFOB

and the ECB are equal. See Appendix C for the listing of present value

costs for each building for all lifespans from 1 through 40 years.
Present

value

cost

($1,000

in

1976)

Figure 3.1

Case I - Present Value Cost^ vs Lifespan for NCFOS and ECB

Lifespan, years

3 Case I - Present value cost is assumed to include the building construction

cost, energy cost as computed for 1962 consumption and GSA

estimates for annual energy price increase.

17
Present

value

cost

($1,000

in

1976)

Figure 3.2

Case II - Present Value Cost ^ vs Lifespan for NCFOB and ECB

Lifespan, years

® Case II - Present value cost is assumed to include the building construction cost, energy cost as computed for 1977 consumption and GSA estimates for annual energy price increase.

18
Present

value

cost

($1,000

in

1976)

Figure 3.3

Case ill - Present Value Cost^vs Lifespan for NCFOB and ECB

Lifespan, years

3 Case III - Present value cost is assumed to include the building construction

cost, energy cost as computed for 1962 consumption and FEA

estimates for annual energy price increase.

19
Present

value

cost

($1,000

in

1976)

Figure 3.4

Case IV - Present Value Cost ^ vs Lifespan for NCFOB and ECB

^ Case IV - Present value cost is assumed to include the building construction

cost, energy cost as computed for 1977 consumption and FEA

estimates for annual energy price increase.

20
4.0

SUMMARY AND RECOMMENDATIONS FOR FURTHER RESEARCH

As a result of this economic evaluation, a brief summary and several

recommendations for further research can be offered.

4.1

SUMMARY

1. It cost $327,000 more to build the NCFOB than the ECB. This additional cost amounts to 4.1 percent of the ECB construction cost estimated to be $7,908,000. Once the design and construction methods

suitable for energy conservation become more widely known and practiced, the additional cost of constructing such an energy conserving

building as compared to a conventional building might be even less.

2. Depending on the assumptions made concerning the levels of energy

consumption, the rates of energy price Increase, and the useful lifespans, the present value savings of investing in the energy conserving features in the NCFOB are all positive and range from a low of

$77,000 to a high of $1,407,000. Based on the most probable set of

assumptions, the present value savings measured in 1976 dollars are $947,900 for a 40 year lifespan and $526,000 for a 20 year lifespan.

3. Depending on the assumptions made concerning the levels of energy

consumption and the rates of energy price increase, the discounted

payback periods range from a low of 6.4 years to a high of 12.8

years. Under the most probable set of assumptions, the discounted

payback period for the additional investment ($327,000) made in the

NCFOB is 6.4 years.

4. The actual energy cost, based on the utility bills paid for the NCFOB

in 1977, is 36 percent more than the computed energy cost based on

the NBSLD calculation for 1962 weather conditions. Of this increase,

only a small percentage can be attributed to the change in weather

conditions. The bulk of the increase cannot be properly explained

until the detailed thermal engineering analysis, currently underway

for the building and equipment, has been completed.

4.2

RECOMMENDATIONS FOR FURTHER RESEARCH

1. I recommend that a study be made on the cost-effective use of the

four gas-fired and two standby oil-fired boilers provided in the

NCFOB. This study should consider the energy cost, operating efficiency and maintenance cost for the cost-effective use of the two

types of boilers. Under present operating condition, the oil-fired

boilers have been used intermittently and sparingly in January,

February, July, August, September and December of 1977. In view of

the current cheaper energy price for fuel oil as compared to that for

natural gas, it appears to be more cost effective at this time to run

the oil-fired boiler more often. However, other factors such as the

operating efficiency and maintenance cost should be included in a study involving the cost-effective use of the two types of boiler.

21
2. I recommend that an economic evaluation be made of various individual energy conserving features such as the alternative lighting

systems, the engine generators, and the heat pumps. The results of

this economic evaluation would help building designers, owners and

operating personnel to select cost-effective investments for energy

conservation in buildings. We anticipate that detailed energy con- sumption data for individual energy conserving features will be measured and monitored by the new computerized energy monitoring and

control system (JC-80), and that these data will be available for

evaluation by the Fall of 1978,

3. I recommend that a more comprehensive economic evaluation be made on

the NCFOB. This economic evaluation should not only Incorporate cost

data on building operation and maintenance, but also the revised

energy consumption data to be derived from the on-going thermal engineering analysis.

22
Appendix A

BUILDING DESIGN AND COST DATA

The following design and cost data have had been extracted from an unpublished report, Nicholas Isaak and Andrew Isaak Comparative Cost

Study As Built vs. Equivalent Conventional Buildings , October 1975. This

report was funded and monitored by the NBS as Contract No. T73183

Request No. 463-3269. These data are divided into three major categories:

(1) Design Criteria Comparison; (2) Building Cost Comparison; and (3)

Demonstration Items.

A.l DESIGN CRITERIA COMPARISON

Both NCFOB and ECB are reinforced concrete structures of seven

^ stories. A comparison of the major design requirements or features

are presented in the following three tables.

With the exception of the underground garage and mechanical and

electric service areas, all spaces are provided with HBAC. The design

requirements of the HVAC. The design requirements of the HVAC systems

are listed in Table A. 2.

Lighting and power design requirements for the buildings are listed

in Table A. 3.

A. 2 BUILDING CONSTRUCTION COST COMPARISON

Itemized NCFOB construction costs and the corresponding ECB con- struction estimates are listed in Table A. 4 below in the Construction

Specification Institute (CSI) format. The costs Include the total con struction costs but exclude site acquisition costs and building design

fees

^ For a full description of the NCFOB, see Nicholas Isaak and Andrew Isaak,

Designing an Energy Efficient Building , A Case Study, (General Services

Administration, September 1975.)

A-1
TABLE A.l

Building Structure and Envelope Design Requirements

Building

Element NCFOB ECB

Roof U = 0.06, insulation is placed

on the exterior side of a 8"

thick concrete roof.

U = 0.15, minimum

insulation is placed on

a 4" thick concrete roof

Wall U = 0.06, 3 3/4" insulation is

placed on the exterior side of

the 12" thick block wall;

granite exterior facing.

U = 0.16, 1" insulation

is placed on a 6" thick

block wall; granite

exterior facing.

Wind ow U = 0.55, window area is 5% of

wall area. Thermally broken

double glazed with built in

Venetian blinds.

U = 1.13, window area

is 40% of wall area,

1/4" plate glass,

single glazed.
Table A.

HVAC Design Requirements

Building

Requirements NCFOB ECB

Winter outdoor

design temperature

(+) 5°F (-) 10°F

Winter indoor

design temperature

(+) 68°F (+) 75°F

Summer outdoor

design conditions

86°F. DB, 73°F. WB 90°F. DB, 73°F. WB

Summer indoor

design conditions

78°F. DB, 60% R.H. 75°F. DB, 50% R.H.

Outside air

ventilation

6 CFM per person

(generally .06 CFM

per square foot of

floor)

0.25 CFM per square

foot of floor

"U" Walls 0.06 BTU/S.F./°F 0. 16 BTU/S.F./°F

"U" Roof 0.06 BTU/S.F./°F 0.15 BTU/S.F./°F

”U" Glass 0.55 BTU/S.F./°F 1.13 BTU/S.F./°F

Shading Building structure No special provisions

designed to be 80 to Venetian blinds for

100% efficient in pro- summer solar reduction

hibiting summer solar

load and 80 to 90%

efficient in permitting

winter solar.
TABLE A.

3

Electrical Design Requirements

Building

Spaces NCFOB ECB

Office Space Lighting = 2W/sq. ft. avg. Lighting = 6W/sq. ft. max

Storage

(Potential Office)

Lighting = 2W/sq. ft. avg. Lighting = 6W/sq. ft. max

Lobbies Lighting = 2.5W/sq. ft. Lighting = 4W/sq. ft.

Toilet Storage & Utilities

Lighting = IW/sq. ft. Lighting = 3W/sq. ft.

Permanent Corridor (None) Lighting = 2W/sq. ft.

Parking 1/2 fc average Lighting =

5 . 10

fc storage,

fc traffic

Office Receptacles IW/sq. ft • IW/sq. ft.

A. 3 DEMONSTRATION ITEMS

Following are specific items installed in the NCFOB strictly for

special experiments or measurements which are not normally required

for the operation of the ECB. Specific item numbers refer to A. 4.

The negative value of the cost differential indicates that the specific

item for the NCFOB costs more than that for the ECB.
Table A.

Building Construction Cost Comparison

NCFOB ECB

ITEM

QUANTITY

UNIT

C0ST($)

TOTAL

C0ST($)

UNIT

QUANTITY C0ST($)

TOTAL

C0ST(S

DIV. 1 GENERAL

1.1 Temporary

facilities 181280 274000

1.2 G.C. equipment 288000 same 288000

1.3 Clean up 30000 same 30000

1.4 Field

Engineering 15000 same 15000

1.5 Field Offices

& Shed 3 each 5000 15000 same 15000

1.6 Field overhead

a

Superintendent 125 wk. 300 37500 same 37500

b. Field engineer 60 wk. 250 15000 same 15000

c

Clerk 100 wk. 200 20000 same 20000

DIV. 1 TOTAL 601780 694500

DIV. 2 SITE WORK

2.1 Earth work

aBuilding

excavation 39000 c.y. 2.39 93060 same 93060

b. Fill & backfill 3000 c.y. 1.62 4860 same 4860

2.2 Pile

Foundations

a

Shoring & shor

removal 18340 s.f. 9.87 181050 same 181050

b. Steel piles 8422 l.f. 14.31 120526 8000 l.f. 14.31 114480

c

Pile caps 1600 c.y. 34.53 55250 same 55250

d. Pvock bolts 1600 l.f. 45.58 72930 same 72930

2.3 Dewa tering 15 mo

3111 46665 same 46665
Table A. 4 Continued

NCFOB ECB

ITEM UNIT TOTAL UNIT TOTAL

QUANTITY COST($) COST($) QUANTITY COST($) COST($)

2.4 Site utilities 11475 same 11475

2.5 Landscaping 12920 same 12920

DIV . 2 TOTAL 598736 592690

DIV . 3 CONCRETE

3.1 Cast in place

concrete

aSub grade walls 682 c.y. 228 155462 same 155462

b. Sub basement slab 1782 c.y. 150 267444 same 267444

c

Basement slab & beams 1344 c.y. 208 273700 same 273700

d. Columns below grade 130 c.y

120 15640 120 c.y. 120 14400

eGr . level slab & beams 1936 c.y. 166 320620 1730 c.y. 166 290320

f

Concrete fireproofing 170 c.y. 138 23460 240 c.y. 138 33120

8- Roof slab & penthouse 635 c.y. 160 101660 276 c.y. 160 44160

h. Concrete topping 351 c.y. 111 39100 same 39100

iPlanters & ret. walls 2885 c.y. 5.42 15640 same 15640

j. Slab on metal floor

deck 1027 c.y. 214 220363 1167 c.y. 214 249738

k. Spandrels above

window none 358 c.y. 250 64500

3.2 Precast concrete 6120 s . f

6.02 36860 4658 s.f. 6.02 27948

DIV,. 3 TOTAL 1469949 1475532

DIV,. 4 MASONRY

4.1 Concrete unit

masonry

aExterior 12 inch 37000 s . f

none

8 inch 3070 s . f . 3.63 145350 750 s.f. 3.20 33312

6 inch none 9660 s.f.
Table A. 4 Continued

NCFOB ECB

ITEM QUANTITY

UNIT

C0ST($)

TOTAL

C0ST($)

UNIT

QUANTITY C0ST($)

TOTAL

COST($)

b. Interior 12 inch 360 s.f. none

8 inch 37400 s.f. 2.78 108612 37400 s.f. 2.78 112423

6 inch 600 s.f. none

4 inch 750 s.f. 3040 s.f.

4.2 Cut Stone

a. Building facing 54968 s.f. 9.27 509553 40584 s.f. 9.27 376214

b. Plaza paving

exterior 6900 s.f. 6.00 54600 same 54600

interior 2200 s.f. 2200 s.f.

DIV,, 4 TOTAL 818115 576549

DIV. 5 METALS

5.1 Structural steel 966 ton 855 851262 810 ton 800 648800

5.2 Misc. metals

aSupport brackets 54968 s.f. 2.59 142367 40584 s.f. 2.25 91314

b. Steel stairs 405 riser 75.44 30555 same 30555

c

Gratings 4365 same 4365

d. Handrails ground 480 l.f. 14.23 6832 same 6832

e

Miscellaneous 42750 same 42750

5.3 Metal deck (all) 84076 s.f. 2.19 184300 118050 s.f. 2.19 258530

5.4 Architectural metal

exhibit case, seals 5985 same 5985

DIV., 5 TOTAL 1268416 1089131
Table A. 4 Continued

NCFOB ECB

ITEM QUANTITY

UNIT COST ($)

TOTAL

COST ($) QUANTITY

UNIT COST ($)

TOTAL

COST ($

DIV. 6 WOOD & PLASTIC

6. 1 Rough carpentry 13847 same 13847

6.2 Finish carpentry 15826 same 15826

DIV. 6 total 29673 29673

DIV. 7 THERMAL & MOISTURE PROTECTION

-

7.1 Waterproofing

a. Below grade

b. Above grade

51740

37653

s . f . s .f . 1.78

1.12

92150

41994

same same 92150

41994

7.2 Building insulation

a. Interior

b. Exterior

69230

54968

s . f . s . f .

.13

.39 873021438

same 42438 s,f. .20 8730

8488

7.3 Insl . metal panel 13817 s . f . 9.54 131860 240 s.f. 4.00 960

7.4 Roofing system 206 s . f . 190 39200 208 sq

130 27040

7.5 Sheetmetal & flashing 37829 28372

7.6 Sealants 26220 19665

DIV. 7 total 399421 227399

DIV. 8 DOORS & WINDOWS

8.1 Hollow metal frames 225 each 34.46 7754 265 each 34.46 9132

8.2 Doors 305 each 91.67 27955 same 27955
Table A. 4 Continued

NCFOB ECB

ITEM UNIT TOTAL UNIT TOTAL

QUANTITY COST ($) COST ($) QUANTITY COST ($) COST ($)

8.3 Aluminum work 2054 s.f18.58 38160 2200 s.f. 18.58 40876

8.4 Special doors 2 each 3000 17164 same 6000

DIV. 8 total 216718 264751

DIV. 9 FINISHES

9.1 Gypsum drywall

a • Column fireproofing 7781 S.f. 4.01 31227 10320 s.f. 4.01 41383

b. Partitions 24543 s.f. 1.18 28889 46500 s.f. 1.18 54870

c

Wall furring 8390 s.f.58 4867 19300 s.f. .58 11194

9.2 Tile work

a

Ceramic tile 8350 s.f. 1.70 14191 same 14191

b. Quarry tile 1000 s.f. 4.24 4239 same 4239

9.3 Acoustical celling 93900 s.f. 1.15 108300 91900 s.f. .74 68006

9.4 Resilient flooring

a

Vinyl asbestos

flooring 15500 s.f

.48 7421 same 7421

b. Stair treads 405 ea. 8.28 3353 same 3353

9.5 Carpeting 7550 s.y. 8.30 62662 same 62662

9.6 Cementicious

coating 14935 s.f. .79 11733 same 11733

9.7 Spray fire

protection 84078 s.f

.43 36100 118050 s.f. .43 50762

9.8 Painting & finishing 37001 same 37001

9.9 Vinyl wall covering 1890 same 1890

DIV. 9 total 351883 368705
Table A. 4 Continued

NCFOB ECB

ITEM QUANTITYUNIT COST ($)TOTAL

COST ($) QUANTITY

UNIT COST ($)

TOTAL

COST ($)

DIV. 10 SPECIALTIES

10.

Toilet partitions 7581 same 7581

10.2 Access flooring 5000 none

10.3 Flag pole 1 ea. 2708 2708 same 2708

10.4 Mail chute 94 i.f29.41 2765 same 2765

10.5 Folding partitions 1167 s . f • 8.00 9336 same 9336

10.5 Relocatable

partitions 22360 s.f • 2.74 61370 same 61370

10.7 Toilet room accessories 7526 same 7526

10.8 Misc. specialties 13088 same 13088

DIV. 10 total 109374 104374

DIV. 11 EQUIPMENT

DIV. 12 FURNISHINGS

DIV. 13 SPECIAL

CONSTRUCT ION

13.1 Radiation

protection 5990 same 5990

DIV. 13 total 5990 5990

A-10
Table A. 4 Continued

NCFOB ECB

ITEM QUANTITY

UNIT COST ($)

TOTAL

COST ($) QUANTITY

UNIT COST ($)TOTAL

COST ($)

DIV. 14 CONVEYING

SYSTEMS

14.1 Dumbwaiters 1 ea. 7220 7220 same 7220

14.2 Elevators

a. Freight 10 stops

b. Passenger 9 stops

1 ea.

2 ea

91748

178099

same same 91748

178099

DIV. 14 total 277067 277067

TOTAL OF ARCHITECTURAL & STRUCTURAL 6147122 5706361

DIV. 15 MECHANICAL

15.1 Plumbing 141913 same 141913

15.2 Boilers/burners 5036 20845

15.3 Pumps 15250 3826

15.4 Oil tanks none 6928

15.5 Oil piping, values,

etc

none 1318

15.6 H.W. heating piping 33028 51593

15.7 Values incl .in 15.6 11022

15.8 Heating specialties 7058 5025

15.9 Radiators & unit

heaters 10541 39997

A-1
Table A, 4 Continued

NCFOB ECB

ITEM QUANTITY

UNIT

COST ($)

TOTAL

COST ($) QUANTITY

UNIT

COST ($)

TOTAL

COST ($)

15.10 Sheet Metal 191304 85113

15. 1

Insulation 103429 75844

15.12 Fans 10963 32387

15.13 Cooling coils none 36595

15.14 Condensing units none 101451

15. 15 Re frig, piping & controls none 21635

15.16 Fil ters 1195 9900

15. 17 Air terminals 90080 - 167004

15.18 Auto. temp,

control 199216 104100

15.19 Balancing & wtr.

t rent

16165 10199

15.20 Generator 49657 25030

15.21 Waste ht. wtr. piping 15693 none

15.22 Chilled wtr. piping 14617 none

15.23 Condenser wtr. piping 29564 none

15.24 Pan drain piping 5441 none

15.25 Heat pump piping 42137 none

15,27 Heat pumps 30395 none

A-12
Table A. 4 Continued

NCFOB ECB

ITEM UNIT TOTAL UNIT TOTAL

QUANTITY COST ($) COST ($) QUANTITY COST ($) COST ($)

15.28 Reciprocat.

chiller 20946 none

15.30 Closed circuit

coolers 23528 none

15.31 Fan coil units 11270 none

15.32 Miscellaneous 33328 same 33328

15.33 Fire protection 93977 same 93977

DIV. 15 total 1195731 944028

DIV. 16 ELECTRICAL

16.1 Distribution

system

a. Conduit & wire 178352 217350

b. Walker duct 36000 same 36000

c. Switchgear & bus duct 58500 60375

d. Pulling wire 39600 54338

e. Trim & finish 31500 same 31500

f. Panls. switch. & transform 29825 42263

16.2 Lighting fixtures 113400 163013

16.3 Snow melt & pipe

tracing 20539 same 20539

16.4 Fire alarm system 18000 same 18000

16.5 Sound system 18000 same 18000

A-13
Table A. 4 Conti,nued

NCFOB ECB

ITEM QUANTITYUNIT

COST ($) COST ($) QUANTITY

UNIT

COST ($) COST ($)

16.6 Grndg. & Itg.

protection 18000 same 18000

16.7 Equip, connect. HVAC 14465 19320

DIV. 16 total 576181 698698

SUMMARY

Architectural/ Structural 6147122 5706361

Mechanical 1195731 - 944028

Electrical 576181 698698

Total 7919034 7349087

G.C. Overhead/Profit 7. 6% 601847 558531

TOTAL CONSTRUCTION COST 8520881 7907620

A-14
Table A.5

'

Demonstration Items In NCFOB

Item No.

Building

NCFOB ECB

Dollar Cost

Differential

8.5 Large area of interior

glazing used around

monitoring computer

room for viewing by

the public.

9.3 Two types of acoustical

ceiling systems used to

demonstrate and comparatively evaluate

various light fixtures.

10.2 Access flooring required

for monitoring computer

room

No computer -3,091

monitoring system.

Single system of

ceiling and lighting -40,294

used

No monitoring system. -5,000

A-15
Table A. 5 Continued

Item

Building

NCFOB ECB

Dollar Cost

Differential

15.10 Multiple mechanical Single system resulted. -106,191

system resulted in

greater quantity of

duct work and control

dampers

15.18 Multiplicity of systems Normal system. -95,116

resulted in more complex

temperature control system.

15.19 Multiplicity of system Normal balancing

resulted in much higher cost,

cost of balancing due to

complexity

16.2 Use of several kinds of

light fixtures increased

the cost estimated to

be about 20% of total

listed in Table A. 4.

Use conventional

lighting design.

-5,966

-9,923

A-16
Table A. 5 Continued

Building

NCFOB ECB

Dollar Cost

Differential

None The cost of the solar None None

energy system^ has not been

included in the estimate

SUBTOTAL COST DIFFERENTIAL -$265,581

GC Overhead/Profit 7.6% -20,184

TOTAL COST DIFFERENTIAL -$285,765^

^ This is a small system provided to supplement building heating requirements.

To date, this solar energy system is not in full operation. This system

will be used to measure the effectiveness and efficiency of solar collectors

of various manufacturers.

^ This total cost differential is used in Table 2.1.

A-17
'v/ • r, .••'- r
APPENDIX B

ENERGY USAGE & PRICE DATA

The energy usage and price data are divided into the following

categories: (1) NCFOB Actual Energy Usage And Prices; (2) NCFOB

Computed Energy Usage; and (3) ECB Computed Energy Usage.

B.l NCFOB ACTUAL ENERGY USAGE & PRICES

The 1977 actual energy usage and energy prices for the NCFOB are derived from the monthly utility bills submitted to the Region I Office

of GSA. Natural gas, fuel oil and electricity bills are included.

Monthly bills for natural gas, as submitted by the Manchester Gas

Co., are used to obtain the usage and price data. These bills reflect

the actual meter readings of the dates shown in Table B.l.

The price of natural gas in 1977 is $0,607 per therm or $6.07

per million Btu.

Billing for the fuel oil was submitted by the Union Petroleum

Corporation and monitored for actual usage by GSA operating personnel.

These bills were used to provide energy use data presented in Table B.2.

The price of No. 2 fuel oil in 1977 is $0.40 per gallon or $2.86 per million Btu.

Monthly electric bills were submitted by the Public Service Co.

of New Hampshire. The electricity usage and price data are derived

from these bills which reflect the actual meter readings on the dates

shown in Table B.3.

B-1
Table B.l

Actual Usage Of Natural Gas For The NCFOB In 1977

Billing Date

Unit Purchase

(Therms)

Energy Content^

(10^ Btu)

1/1 2/12 4,099.6 0.410

2/12 3/10 2,488.8 0.249

3/10 4/11 2,332.2 0.233

4/11 5/11 1,236.2 0.124

5/11 6/13 1,859.3 0. 186

6/13 8/09 3,172.1 0.317

8/09 9/14 2,374.2 0.237

9/14 10/13 561.7 0.056

10/13 11/14 641.3 0.064

11/15 12/31 6089.4 0.609

TOTAL 24854.8 2.421

^ One therm is 0.0001 x 10^ Btu.

B-2
Table B.2

Actual Usage of No. 2 Fuel Oil For The NCFOB In 1977

Month

Units Purchase

Gallon

Energy Content^

xlO Btu

January 1,550 0.217

February 570 0.080

July 590 0.083

August 1,010 0.141

September 150 0.021

December 1 ,850 0.259

TOTAL 5,720 0.801

^ One gallon of No. 2 fuel oil contains approximatly 0.00014 x 10^ Btu.

B-3
Table B.3

Actual Electricity Usage For The NCFOB In 1977

Billing Dates

Units Purchased

(kWh)

Energy Content^

(10^ Btu)

12/15 1/13 170,800 0.583

1/14 2/11 148,800 0.508

2/11 3/14 136,000 0.464

3/14 4/15 135,200 0.462

4/15 5/16 118,800 0.406

5/16 6/16 130,800 0.447

6/16 7/15 128,400 0.438

7/15 8/16 149,200 0.509

8/16 9/15 132,400 0.452

9/15 10/14 102,000 0.348

10/14 11/15 101,600 0.347

11/16 12/14 146,800 0.501

TOTAL 1,600,800 5.465

^ One kWh of electricity contains approximately 0.000003414 X 10^ Btu,

The price of electricity in 1977 is $0.0354 per kWh or $10.37

per million Btu.

B.2 NCFOB PREDICTED ENERGY USAGE

The following NCFOB energy usage data were extracted from the

NBSLD computer run for the final building design, as listed in a report, Tamami Kusuda, James E. Hill, Stanley T. Liu, James P. Barnett

and John W. Bean,

B-4
Pre-Design Analysis of Energy Conservation Options For A Multi-story

Demonstration Office Building , U.S. Department of Commerce, National

Bureau of Standards, Building Science Series 78, November 1975.

Weather data for 1962 were used for the computation.

Table B.4

Annual Total Energy Usage For The NCFOB In 10^ Btu

Month Usage (10^ Btu)

1 0.776

2 0.726

3 0.607

4 0.470

5 0.420

6 0.357

7 0.364

8 0.401

9 0.314

10 0.470

11 0.545

12 0.726

TOTAL 6. 176

B-5
According to data extracted from Figure 26 of the above referenced

report, the predicted total annual energy usage of 6.176 x 10^ Btu

shown in Table B.4 can be divided into the heating energy of 2.290 x

10^ BTU and the electrical energy of 3.886 x 10^ BTU.

B.3 ECB COMPUTED ENERGY USAGE

The following ECB energy usage data were extracted from the NBSLD

computer run number 2, modified, as referred to in the report, Tamami

Kusuda, James E. Hill, Stanley T. Liu, James P. Barnett and John W. Bean,

Pre-Design Analysis of Energy Conservation Options For A Multi-story

Demonstration Office Building , U.S. Department of Commerce, National

Bureau of Standards, Building Science Series 78, November 1975. Weather

data for 1962 were used for the computation.

For the ECB, the annual energy usage is estimated to be 12.260 x 10

Btu which is composed of 4.983 x 10^ Btu for heating and 7.277 x 10^ Btu

for electricity.

9

B-6
Table B.5

Annual Heating Energy For The ECB In 10^ Btu

Function

Month Space Heating Hot Wa ter Total

1 1.083 .037 1.120

2 0.992 .032 1.024

3 0.515 .037 0.552

4 0.197 .035 0.232

5 0. 133 .037 0. 170

6 0 .035 0.035

7 0 .033 0.033

8 0 .038 0.038

9 0 .032 0.032

10 0.189 .038 0.227

11 0.437 .035 0.472

12 1 .015 .033 1.1048

TOTAL 4.561 .422 4.983

B-7
1

2

3

4

5

6

7

8

9

10

11

12

Table B.6

Annual Electricity Usage For The ECB In 10^ Btu

Function

Cooling Fans Pumps Lighting Mi sc Total

.002 .043 .069 0.373 .069 0.556

.001 .037 .062 0.323 .060 0.483

.022 .043 .069 0.373 .069 0.576

.066 .041 .066 0.357 .066 0.596

.144 .043 .069 0.373 '.069 0.698

.183 .041 .019 0.357 .069 0.669

.183 .040 .018 0.339 .063 0.643

.214 .045 .021 0.391 .072 0.743

.140 .037 .017 0.323 .060 0.577

.099 .045 .069 0.391 .072 0.676

.016 .041 .066 0.357 . 066 0.546

.001 .040 .069 0.339 .063 0.514

1.073 .500 .613 4.297 .794 7.277

B-8
Appendix C

YEAR-BY-YEAR PRESENT VALUE COSTS

The following data are the year end present value costs of owning

and operating (energy consumption only) the NCFOB and ECB calculated

with various combinations of energy consumption and energy price

increase explained in Sections 2.0 and 3.0. These data form the basis

of Figures 3.1 through 3.4.

C-1
Year

1976

1977

1978

1979

1980

1981

1982

1983

1984

1985

1986

1987

1988

1989

1990

1991

1992

1993

1994

1995

1996

1997

1998

1999

2000

2001

2002

2003

2004

2005

2006

2007

2008

2009

2010

2011

2012

2013

2014

2015

2016

Table C.l

Present Value Cost Of The NCFOB At Year End ($1000)

Combination 1 1977 Consumption

& GSA Price

Rise

Combination 2 1977 Consumption

& FEA Price Rise

Combination 3 1962 Consumption

& GSA Price

Rise

Combination 4 1962 Consumption

& FEA Price Rise

$8235.00 $8235.00 $8235.00 $8235.00

8302.01 8302.01 8284.27 8284.27

8372.67 8363.61 8336.23 8329.61

8447.18 8420.25 8391.03 8371.33

8525.76 8472.35 8448.81 8409.73

8601.48 8520.27 8504.49 8445.09

8674.45 8564.35 8558, 15 8477.65

8744.76 8604.93 8609.86 8507.63

8812.52 8642.27 8659.68 8535.25

8877.81 8676.64 8707.70 8560.71

8940.73 8708.30 8753.96 8584.16

9001.37 8737.45 8798.55 8605.79

9059.79 8764.30 8841.51 8625.72

9116.09 8789.04 8882.92 8644.11

9170.35 8811.84 8922.81 8661.07

9222.63 8832.57 8961.26 8676.49

9273.01 8851.41 8998.31 8690.51

9321.56 8868.54 9034.01 8703.25

9368.34 8884.11 9068.41 8714.83

9413.43 8898.27 9101.56 8725.36

9456.87 8911.14 9133.51 8734.94

9498.73 8922.84 9164.29 8743.64

9539.07 8933.47 9193.95 8751.55

9577.95 8943.14 9222.54 8758.74

9615.41 8951.93 9250.09 8765.28

9651.50 8959.92 9276.63 8771.23

9686.29 8967. 19 9302.21 8776.63

9719.81 8973.79 9326.86 8781.54

9752. 11 8979.80 9350.61 8786.01

9783.24 8985.25 9373.50 8790.07

9813.23 8990.22 9395.56 8793.76

9842.14 8994.73 9416.82 8797.12

9869.99 8998.83 9437.30, 8800. 17 9896.83 9002.56 9457.03 8802.94

9922.70 9005.94 9476.05 8805.46

9947.62 9009.03 9494.38 8807.75

9971.64 9011.83 9512.04 8809.84

9994.78 9014.37 9529.06 8811.73

10017.1 9016.69 9545.46 8813.45

10038.6 9018.79 9561.27 8815.02

10059.3 9020.70 9576.50 8816.44

TFZ
Year

1976

1977

1978

1979

1980

1981

1982

1983

1984

1985

1986

1987

1988

1989

1990

1991

1992

1993

1994

1995

1996

1997

1998

1999

2000

2001

2002

2003

2004

2005

2006

2007

2008

2009

2010

2011

2012

2013

2014

2015

2016

Table C.2

Present Value Costs Of The ECB At Year End ($1000)

Combination 1 1977 Consumption

& GSA Price

Ri se

Combination 2 1977 Consumption

& FEA Price Rise

Combination 3 1962 Consumption

& GSA Price

Rise

Combination 4 1962 Consumption

& FEA Price Rise

$7908.00 $7908.00 $7908.00 $7908.00

8013.73 8013.73 8004.09 8004.09

8125.22 8111.10 8105.42 8092.59

8242.80 8200.80 8212.28 8174.11

8366.79 8283.44 8324.97 8249.21

8486.27 8359.60 8433.56 8318.43

8601.40 8429.80 8538.20 8382.22

8712.35 8494.53 8639.04 8441.04

8819.26 8554.22 8736.21 8495.28

8922.29 8609.27 8829.85 8545.31

9021.57 8660.06 8920.08 8591.46

9117.24 8706.93 9007.03 8634.06

9209.43 8750.20 9090.82 8673.37

9298.27 8790.14 9171.56 8709.66

9383.88 8827.02 9249.36 8743.17

9466.37 8860.55 9324.34 8773.64

9545.87 8891.04 9396.59 8801.33

9622.47 8918.75 9466.21 8826.51

9696.29 8943.94 9533.30 8849.40

9767.43 8966.84 9597.95 8870.21

9835.98 8987.66 9660.25 8889. 13 9902.03 9006.59 9720.29 8906.32

9965.68 9023.79 9778. 14 8921.96

10027.00 9039.44 9833.89 8936.17

10086. 10 9053.66 9887.61 8949.09

10143.10 9066.58 9939.37 8960.84

10198.00 9078.34 9989.26 8971.51

10250.90 9089.02 10037.3 8981.22

10301.80 9098.73 10083.7 8990.05

10351.00 9107.56 10128.3 8998.07

10398.30 9115.59 10171,3 9005.36

10443.90 9122.89 10212.8 9011.99

10487.80 9129.52 10252.7 9018.02

10530.20 9135.55 10291.2 9023.50

10571.00 9141.03 10328.3 9028.48

10610.30 9146.02 10364.0 9033.01

10648.20 9150.55 10398.5 9037. 13 10684.70 9154.67 10431.7 9040.87

10719.90 9158.41 10463.6 9044.27

10753.80 9161.82 10494.5 9047.37

10786.50 9164.91 10524.2 9050. 18

C-3
Year

1976

1977

1978

1979

1980

1981

1982

1983

1984

1985

1986

1987

1988

1989

1990

1991

1992

1993

1994

1995

1996

1997

1998

1999

2000

2001

2002

2003

2004

2005

2006

2007

2008

2009

2010

2011

2012

2013

2014

2015

2016

Table C.3

Present Value Costs Of The ECB At Year End ($1000)

Combination lA

Adjusted 1977

Consumption & GSA Price

Rise

Combination 2A

Adjusted 1977

Consumption & FEA Price

Rise

$7908.00

8038.69

8176.52

8321.86

8475. 13

8622.82

8765.15

8902.30

9034.46

9161.81

9284.54

9402.80

9516.76

9626.58

9732.40

9834.38

9932.65

10027.30

10118.60

10206.50

10291.30

10372.90

10451.60

10527.40

10600.50

10670.90

10738.70

10804.10

10867.10

10927.80

10986.40

11042.70

11097. 10

11149.40

11199.90

11248.50

11295.30

11340.50

11384.00

11425.90

11466.30

$7908,00

8038.69

8159.06

8269.94

8372.10

8466.24

8553.02

8633.03

8706.80

8774.86

8837.64

8895.58

8949.05

8998.42

9044.01

9085.45

9123. 13

9157.38

9188.52

9216.83

9242.56

9265.96

9287.23

9306.56

9324. 14

9340.12

9354.64

9367.85

9379.85

9390.77

9400.69

9409.71

9417.91

9425.36

9432. 14

9438.30

9443.90

9448.99

9453.62

9457.83

9461.65

C-4
REFERENCES

1. American Society of Heating Refrigerating and Air-Conditioning

Engineers Inc,, ASHRAE Handbook of Fundamentals , New York, 1972.

2. Grant, Eugene L, and Ire son, W. Grant, Principles of Engineering

Economy , 5th Edition, New York: The Ronald Press Co., 1970.

3. Isaak, Nicholas and Issak, Andrew, Comparative Cost Study As Built

vs. Equivalent Conventional Buildings , Unpublished report

contracted by the NBS, contract No. T 73183, October 1975.

4. Isaak, Nicholas and Isaak, Andrew, Designing An Energy Efficient

Building: A Case Study , General Services Administration,

September 1975.

5. Kusuda, Tamami; Hill, James E. ; Liu,, Stanley T. ,

Barnnett,

James P. ; and Bean, John W,, Pre-Design Analysis of Energy

Conservation Options for a Multi-Story Demonstration Office

Building , U.S. Department of Commerce, National Bureau of

Standards, Building Science Series 1978, November 1975.

6. The National Archives of the United States, "Energy Audit

Procedure: Proposed Rules and Hearing," Federal Register , Vol. 42, No. 73, April 15, 1977.

D-1
I)

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iBS.114A IREV. I I-77I

0-vS. DEPT. OF COMM. BIBLIOGRAPHIC DATA

SHEET

4. TITLE AND SUBTITLE

1. PUBLICATION OR REPORT NO. NBSIR 78-1568

2. Gov’t Accession

No.

Economic Analysis of the Norris Cotton Federal Office

Building

7. AUTHOR(S)

Phillip T. Chen

9. PERFORMING ORGANIZATION NAME AND ADDRESS NATIONAL BUREAU OF STANDARDS DEPARTMENT OF COMMERCE

WASHINGTON, D.C. 20234

12. Sponsoring Organization Name and Complete Address (Street, City, State, ZIP) The Department of Energy

Washington, D.C. 20461

3. Recipient’s Accession No.

5. Publication Date November 1978

6. Performing Organization Code

8. Performing Organ. Report No.

10. Project/Task/Work Unit No.

11. Contract/Grant No.

13. Type of Report & Period Covered Final

14. Sponsoring Agency Code

15. SUPPLEMENTARY NOTES

16. ABSTRACT (A 200-word or less tactual summary of most sigrtificant information. If document includes a significant bibliography or literature survey, mention it here.) The Norris Cotton Federal Office Building in Manchester, New Hampshire, has been

constructed and occupied by the General Services Administration to demonstrate

energy conservation techniques in the design and operations of a contemporary

office building. This post-occupancy economic evaluation conducted by the National

Bureau of Standards shows that additional construction costs incurred in order to reduce the energy consumption of the building are adequately offset by the present

value of the resulting annual energy savings. In the economic model, the actual

construction cost and energy consumption of the constructed building are compared

with the estimated construction cost and energy consumption of a hypothetical

equivalent conventional building. The present value costs of the two buildings are calculated for each year during a 40-year study period.

17. KEY WORDS (six to twelve entries; ajphabeticel order; capitalize only the first letter of the first key word unless a proper name; separated by semicolons) Building; construction cost estimation; discounted payback period; economic analysis;

economic evaluation; energy conservation; life—cycle costing; present value

analysis

18. AVAILABILITY Unlimited c For Official Distribution. Do Not Release to NTIS

I

I Order From Sup. of Doc., U.S. Government Printing Office Washington, D.C. 20402, SD_^Stock_^o^_SN00^3^^

I XI Order From National Technical Information Service (NTIS)

Springfield, Virginia 22151

19. SECURITY CLASS

(THIS REPORT)

UNCL ASSIFIED

20. SECURITY CLASS

(THIS PAGE)

UNCLASSIFIED

21. NO. OF PAGES

60

22. Price $5.25

USCOMM-OC 66035-P7£
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