NBSIR 76-1056

Analysis of Solar Energy System

for the GSA Demonstration

Office Building at Manchester,

New Hampshire

Tamami Kusuda

Stanley T. Liu

John W. Bean

James P. Barnett

Center for Building Technology

Institute for Applied Technology

National Bureau of Standards

Washington, D. C. 20234

March 1, 1976

Final Report

Prepared for Federal Energy Administration

New Post Office Buillding

1 2th and Pennsylvania Avenue

Washington, D. C. 20461

NBSIR 76-1056

ANALYSIS OF SOLAR ENERGY SYSTEM

FOR THE GSA DEMONSTRATION

OFFICE BUILDING AT MANCHESTER,

NEW HAMPSHIRE

Tamami Kusuda

Stanley T. Liu

John W. Bean

James P. Barnett

Center for Building Technology

Institute for Applied Technology

National Bureau of Standards

Washington, D. C. 20234

March 1, 1976

Final Report

Prepared for Federal Energy Administration

New Post Office Building

12th and Pennsylvania Avenue

Washington, D. C. 20461

U.S. DEPARTMENT OF COMMERCE, Elliot L. Richardson, S^eMfary

James A. Baker, III, Under Secretary

Dr. Betsy Ancker-Johnson. Assistant Secretary for Science and Technology

NATIONAL BUREAU OF STANDARDS, Ernest Ambler. Acting Director

TABLE OF CONTENTS

Page

1. Introduction 1

5 2. HVAC Systems Used in the GSA/Manchester Building 2

3. Load Calculation for the Building 3

4. Simulation of Flat-Plate Collector Performance 4

5. Solar-Assisted Heating 6

6. Solar-Assisted Cooling 8

10 7 . Summary 8

8. References 9

9. Appendix A - Air System Simulation 10

i
Analysis of Solar Energy System for the GSA Demonstration

Office Building at Manchester, New Hampshire

Tamami Kusuda

Stanley T. Liu

John W. Bean

James P. Barnett

5 Thermal Engineering Section

Building Environment Division

Center for Building Technology

Institute for Applied Technology

ABSTRACT

The energy conservation demonstration building of the General Ser10 vices Administration to be built in Manchester, New Hampshire, has been

planned to be partially heated and cooled by solar energy. Presented in

this report are results of a study made at the National Bureau of Standards to determine the effect of solar collector sizes and the amount of

storage on the overall energy consumption of the building. It was found

that the fuel savings attainable by the use of solar energy for heating

and cooling of the building will be less significant as the size of the

collector and the amount of storage are increased beyond certain limits.

15 Key Words: Eneirgy conservation; GSA/Manchester Building;

solar collector; solar heating and cooling;

thermal storage

ii
Illustrations

5

Figure 1 Schematic Drawing of the Solar-Assisted Heating and Cooling

System of the GSA/Manchester Building

Figure 2 Air System Employed in the Upper Four Floors of the GSA/Manchester Building

Figure 3 Part-Load Performance of the Electric Chiller Used for the

Solar Energy Simulation Analysis

Figure 4 Typical Solar Collector Efficiency as a Function of Temperature Difference Between the Absorber Surface and Cover Plate

Figure 5 Maximum Temperature Difference Between the Absorber Surface

and the Cover Plate as a Function of Incident Solar Radiation

10 Figure 6 Calculated Hourly Heating Requirement and Collected Solar

Energy During January 18 and 19, 1962

Figure 7 Calculated Cumulative Collected Solar Energy During January

and February 1962

Figure 8 Calculated Daily Collected Solar Energy and Daily Heating

Requirement for the Top Floor During January 1962

15

20

Figure 9 Energy Balance for the Solar-Assisted Heating System

Figure 10 Hourly Profiles of Solar Heat Collected at 140 F (60 C)

,

Space Heating Requirement, and Boiler Fuel Energy Consumption

Figure 11 Energy Balance for the Solar-Assisted Cooling System

Figure 12 Hourly Profiles of Solar Heat Collected at 220 F (104.4 C)

,

Cooling-Coil Load, and Fuel Energy Requirement at the EngineDriven Generator

Figure 13 Effect of Collector Size on the Energy Consumption for Heating and Cooling of the Upper Four Floors in the GSA/Manchester

Building

Figure 14 Effect of Thermal Storage Size on the Energy Consumption for

Heating and Cooling of the Upper Four Floors in the GSA/Manchester Building

iii
Tables

Table 1 Results of the Solar-Assisted Heating System Analysis

Table 2 Results of the Solar-Assisted Cooling System Analysis

iv
1. Introduction

The General Services Administration is constructing a seven-story

office building in Manchester, New Hampshire, to demonstrate energy con- servation features, architectural characteristics, HVAC system design

and building operation. In addition to incorporating numerous conventional energy saving features, this building is to be equipped with a

5 solar energy system to assist in reducing the fossil-fuel requirement

for heating and cooling.

The application of a solar system to office buildings has not yet

been widely practiced, although there is some evidence that this application will be given more and more emphasis for several reasons [1]*:

a. Office buildings usually have simultaneous heating and

cooling requirements over long periods of the year,

which results in a full utilization of the collected

10 energy.

b. Most energy conserving designs for these buildings

already include thermal storage, thus avoiding this

incremental addition to the cost of the solar system.

c. Many systems will require a small thermal storage system (relative to the collector area) since less nighttime heating and cooling are typically needed.

15 d. Absorption cooling equipment is available in the 100-

ton (351,680 W) range which can use the relatively low

water temperatures (200 - 220 F (93.3 - 104.4 C)) available from some high performance flat-plate collectors.

e. There are fewer aesthetic and architectural constraints

to utilizing solar collectors in commercial buildings

compared with small houses, where the collector usually

dominates the roof.

20 The National Bureau of Standards was asked by GSA to work with an architectural and engineering firm in analyzing the building's predicted

energy consumption as a result of various alternative designs of the

building exterior envelopes and HVAC systems. In a previous report [2],

detailed computer analyses for heating and cooling loads for 43 different designs were described. This report deals mainly with the analysis

of the solar system.

See references at end of narrative.
In the first part of this paper, a brief description of the HVAC

system to be employed in the building is given, followed by the results

of the calculation of predicted cooling-coil load and boiler load. Results of solar-assisted heating and cooling simulation studies are then

given in which solar collector performance data reported by the University of Pennsylvania report [3, 4] are used. Only the energy consumption

of the upper four floors is addressed in this report, since the lower

three floors are not to be connected to the central air system and con-

^ sequently will not utilize any of the collected energy.

10

15

20

25

2. HVAC Systems Used in the GSA/Manchester Building

Several different heating and air conditioning systems, which are known to have energy-conserving characteristics, will be used in this

building to demonstrate energy conservation. The first three floors of

the building will be equipped with a closed water-loop-type heat pump

system so that the heat emitted by lights and occupants is used as the

heat source for perimeter heating. The chilled air produced by the core

zone heat pump will be distributed over the space via variable volume air

diffusers

.

The space heating and cooling for the fourth floor and above will

be provided by a central air system connected to a combination of an electrically-driven water chiller and an absorption chiller located in

the penthouse of the building. A 140-KW generator driven by a gas engine

will provide power to the electric chiller. The absorption chiller will

be driven by the heat received from the natural-gas engine jacket water

cooling system. A representation of the penthouse plant is shown in Figure 1. As can be seen, there are supplementary boilers, a domestic hot

water generator, and a solar energy collection system.

The electric chiller will be equipped with a double-bundle condenser

so that a portion of heat rejected from the refrigeration process can

be utilized to provide heating to perimeter zones, if required, while

the core zone is being cooled. An evaporative cooler will be installed

to keep the water loop of the heat pump system used on the first three

floors from becoming too hot during the summer when perimeter heating is

not required.

The chilled water produced at the electrical and absorption chillers

will be delivered to the chilled water coil in the central air handling

system to provide cooling air to the upper four floors. The perimeter

heating for these upper floors will be done differently from the lower

floors. On the fourth floor, baseboard units will be supplied with warm

water from the double-bundle condenser. On the fifth floor, the perimeter zone temperature will be regulated by double-duct systems; the source

for the hot air duct will be a fan-coil unit fed with the hot water from

the double-bundle condenser. On the sixth and seventh floors, four-pipe

2
fan-coil units will be installed to provide heating as well as cooling

to the perimeter zone. Being a four-pipe system, the two upper floors

can be heated or cooled simultaneously. The four-pipe fan-coil units

of these floors can also be operated in the two-pipe mode.

3. Load Calculation for the Building

5

Heating and cooling loads for the space air conditioning were previously calculated on an hourly basis by using 1962 weather data provided

by the National Weather Record Center in Asheville, North Carolina. In

this calculation, a computer program called NBSLD [5] was used to determine hourly heating and cooling loads for four different zones and the

data were recorded on four different magnetic tapes each for the top

floor, middle floor, ground and second floors. This resulted in a total

of sixteen magnetic tapes for the building analysis. The thermal loads

for the 3rd, 4th, 5th and 6th floors were considered to be the same as

10 that for a middle floor. These hourly loads were summarized independently

for the heating and cooling parts for the upper four floors and the resultant summary loads were then balanced in a mathematical simulation

against the heating and cooling capacities of the central equipment in

the penthouse.

As mentioned previously, the central equipment will consist of a gas engine-generator unit, an electric chiller with a double-bundle condenser, a heat recovery unit for the engine jacket water, an absorption

chiller operated by the engine waste heat, and a supplementary boiler to

15 assist in the perimeter heating (which is done mostly by the warm water

from the double-bundle condenser) . The chilled water from the electrical and absorption chillers will be fed to the cooling coil in the central air handling unit. This air handling unit will supply the chilled

air to the central or core zone of the upper four floors while the perimeter heating or reheating zone will be fed by the warm water from the

double-bundle condenser. The air supply system to the core zone will be

equipped with variable volume (VAV) outlets so that the supply airflow

rates can be regulated to match the zone cooling load as long as it is

larger than the minimum outdoor ventilation air rate.

20

For many days in Manchester, New Hampshire, heating becomes necessary even during the summer due to low outdoor air temperatures. In order to help minimize the heating load, an exhaust air heat recovery unit

utilizing heat pipes will be used to recover heat from the toilet exhaust

air. Although actual air handling systems are quite complex, a simplified schematic diagram such as Figure 2 was used to simulate the air-side

performance for the upper four floors. Figure 3 shows the part-load power

consumption characteristics of the electric chiller used to estimate the

first requirement for the engine generator and the heat available from

25 the engine jacket and exhaust-hood heat exchanger. Appendix A contains

the computer algorithm used for simulating the air-side performance of

the system depicted in Figure 2.

3
The hourly supplementary heating requirement was determined by sum- ming the available heat from the double-bundle condenser and the stored

heat in a 10 ,000-gallon water tank and subtracting from it the space

heating and the ventilation air heating load.

The hourly value of cooling-coil load required by the central air

conditioning system to provide 60 F (15.6 C) supply air temperature to

the VAV units was also determined. In this simulation, whenever the out

door air temperature was such that the 60 F (15.6 C) supply air temperature could be obtained by increasing the supply of outdoor air beyond

the ventilation air requirement, the cooling coil was turned off or the

coil load was set equal to zero to simulate the operation of an economizer cycle. The hourly coil load and supplementary heating requirement

were next compared to the heating and cooling capacities available from

the solar energy system,

4. Simulation of Flat-Plate Collector Performance

The energy collected by a flat-plate collector depends upon the fol

lowing parameters

Incident solar radiation

. Ambient temperature

Collector-plate (absorber) temperature

Wind velocity and direction

Type of glazing

Emissivity (e) and absorptivity (a) of the absorber surface

Thermal properties of the insulation that surrounds the absorber plates

Air convection patterns in the space between the absorber and cover plate

Cloud cover

Moisture and CO2 content of the atmospheric air

Although it is possible to write a comprehensive analytical simulation

model that takes into account most of these parameters, the approach em- ployed in this report was to develop an empirical routine based on the

performance of double-glaze collectors reported by the University of

Pennsylvania [3, 4].
15

The performance of collectors having a common black absorber and

selective black absorber (a = 0.94, e = 0.1 ~ 0.15) were reported in the

form of curves showing collector efficiency versus temperature difference between the absorber surface and the cover-plate surface (Figure 4)

.

Since the cover-plate surface temperature is usually unknown, a modification was made to replace the cover-plate temperature by the ambient air

temperature. The efficiency curves may be approximated by straight lines

in the form of

_ ^ _ energy collected /, s I incident solar radiation

\ max /

10 where

20

At = temperature difference between the absorber plate

and cover plate = t - t

c s At = intercept of the efficiency curve with the At axis

max ,

. , . ^ ^ , , or the maximum temperature difference between the cover plate and the absorber surface

t^ = absorber surface temperature

t^ = cover-plate surface temperature

n = intercept of the efficiency curve with the vertical axis

The value of At„„„ depends upon the incident radiation and the results

max

of the experiments also show (Figure 5) that it is possible to approximate At by a linear function such that

max

At = b • I (3) max

The data on the double-glaze collector can be reduced to yield

b = 1.375

25 for the selective surface absorber plate and

b = 0.713

5
for the common black surface absorber. The same data shows that the best

numerical value for n is 0.78.

o There exists the following heat transfer relationship between the

cover-plate temperature tg and the ambient temperature t^ if it is as- sumed that a heat loss from the collector takes place through the cover

plate.

5

h (t^ - t ) = I - Q = I (1 - n) (4)

S a.

where h = surface heat transfer coefficient at the outer cover plate.

Combining equations (2), (3), and (4), results in the following equation,

which is useful for approximating the solar collector efficiency as a function of incident solar radiation I, ambient temperature t , and aba, sorber surface temperature t :

10

1 -

I c

n + hb

o

(5)

Since the value of h is directly related to the wind speed over the cover

plate, equation (5) accounts for the wind as well.

The value of solar collector efficiency can thus be evaluated for

every hour throughout the day by knowing the hourly data on h, I, and t^

for given values of t^,, rio> and b, which are the basic parameters of the

specific collector. The available solar energy, I, impinging on the collector surface was estimated for Manchester by modifying the cloudlessday solar radiation data computed within NBSLhI/ by the cloud cover data

taken from the weather tape. The cloudless solar radiation data for this

particular locality were calculated according to the method described in

the 1972 Handbook of Fundamentals [6] , whereas the cloud cover modification was carried out by incorporating the Boeing solar transmissivity

data [7].

5. Solar-Assisted Heating

Figure 6 illustrates the results of calculations for typical winter

days (January 18 and 19, 1962). The figure shows the hourly solar energy

collected per unit area of collector at a temperature level of 140 F

(60 C) together with the outdoor temperature and heating load of the top

2^ floor in the building. As can be seen, a mismatch exists between the

heating load and the solar energy collected, resulting from the time

difference between the occurrence of the maximum heating demand and the

6
maximum solar energy availability. Thus, it is clear that some kind of

storage device is necessary in order to be able to properly utilize the

solar energy collected. The areas under the solar energy and heating

load curves indicate total daily solar energy and total daily load re- quirements respectively. The total daily collected energy at 140 F

(60.0 C) during January 18, 1962 was estimated to be 343 Btu/ft^ (3.89 x

106 J/m2) of collector, while the total daily heating load of the top

floor during January 19 was 448,000 Btu (4.72 x 10^ j) . Therefore, if

5 one installed a storage tank of 10,000 gallons (37.85 m^) and a collector

having an area of 1,000 ft^ (92.9 m^) , it would be possible to supply

70% of the top-floor heating requirements, assuming that the temperature

drop in the tank is limited to 5 F (2.8 C) . The temperature change that

would occur would increase linearly as the storage tank size is reduced.

Figure 7 shows the cumulative collected and stored solar energy as

a result of using a double-glaze, south-facing collector tilted up at an angle of 60° during the month of January 1962. If the average collected

energy was estimated on the basis of the 30-day total, the solar system

10 could be sized assuming a daily collection of 360 Btu/ft^ (4.09 x 10°

J/m2) of collector area if the fluid temperature were maintained at 100 F

(37.8 C). The same figure indicates, however, that if a 140 F (60.0 C)

fluid temperature is assumed, the collector should be sized on the basis

of 240 Btu/ft^ (2.72 J/m^) of collector area.

The most important factor to be considered in the design of a solar

system is the coincident nature of the collected and required energy.

To demonstrate this. Figure 8 was prepared from the simulation of the

top floor. The figure shows in shaded bars the collected energy by a

15 3,000 ft2 (278.7 m2) double-glaze collector during January, The white

bars show the heating load. The figure shows clearly that there are

days in which energy from storage and/or an auxiliary source would be

required

.

Figure 9 depicts the manner in which the solar energy is actually to

be utilized to assist in the heating of the upper four floors of the GSA/

Manchester Building. The energy produced in the double-bundle condenser

will be used to supply the perimeter fan-coil units when the cooling system for the core zone is operating. This energy will be supplemented by

20 solar energy as required, or if the energy from the solar system is inadequate, the supplementary gas-fired boiler will be operated to satisfy

the need.

Figure 10 shows the heating requirement, energy available from the

solar collector and the fuel consumed by the boiler for a selected period

of 5 days in December 1962. The calculations were carried out hour-byhour for all heating months in order to determine the boiler fuel requirement as a result of using various combinations of collectors and storage.

The results are shown in Table 1.

7
6. Solar-Assisted Cooling

Figure 11 represents schematically the solar energy-assisted cooling

system for the upper four floors of the GSA/Manchester Building. The

energy collected at 220 F (104.4 C) will be used to operate the absorption chiller, which is assumed to have a coefficient of performance of

0.6. I'Then solar energy is not available or is inadequate, the same ab5 sorption chiller will be operated by the waste heat recovered from the

engine generator, which in turn drives the electric chiller.

Figure 12 shows, for a selective period of five days in August 1962,

the hourly profiles of cooling requirements for the upper four floors,

the solar energy collected at 220 F (104.4 C) , and the engine fuel re- quirements. The collector size and the heat storage size were varied as shown in Table 2. The results are shown graphically in Figures 13 and

14. These tables and graphs show that more energy saving can be obtained

by increasing the collector size (up to a certain point) than by increas10 ing the storage capacity.

' ' - - 7 . Summary

Annual energy consumption for the heating and cooling of the upper

four floors of the GSA/Manchester Building was estimated by simulating

the thermal performance of its HVAC system and solar energy system. By

incorporating a 5,000 ft^ (464 m^) collector having a double-glaze cover

15 plate and an absorber surface with a selective surface, in conjunction

with 10,000 gallons of water storage, it is possible to reduce the fuel

consumption by approximately 50% for both heating and cooling. The use

of a larger collector and the amount of storage does not appear to be

warranted, because of the diminishing return in the energy saving.

8
8. References

1. Dub in, F. S., "Statement to the Subcommittee on Energy of the House

Science and Astronautics Committee", Congressional Record, June 12,

1973.

2. Kusuda, T., Hill, J. E., Liu, S. T., Barnett, J. P., and Bean, J. W.,

5 "Pre-Design Analysis of Energy Conservation Options for a Multi-Story

Demonstration Office Building, NBS Building Science Series 78, November 1975.

3. Altman, M. , "Conservation and Better Utilization of Electric Power

by Means of Thermal Energy Storage and Solar Heating", Phase II Progress Report, No. NSF/RANN/SE/G127976/72/4, December 31, 1972.

4. Lorsch, H. G., "Performance of Flat Plate Solar Collectors", Proceedings of the Solar Heating and Cooling for Buildings Workshop, Part 1:

10 Technical Sessions , The National Science Foundation, Washington, D.C.,

March 21-22, 1973.

5. Kusuda, T., "NBSLD, Heating and Cooling Load Calculation Program",

NBSIR 74-574, November 1974.

6. ASHRAE Handbook of Fundamentals , American Society of Heating, Refrigerating and Air-Conditioning Engineers, 345 East 47th Street, New

York, New York 10017.

15 7. "Procedures for Determining Heating and Cooling Loads for Computerized Energy Calculations", ASHRAE Task Group on Energy Requirements

for Heating and Cooling, American Society of Heating, Refrigerating

and Air-Conditioning Engineers, 345 East 47th Street, New York, New

York 10017.

USCOMM-NBS-DC
9. Appendix A - Air System Simulation

Nomenclature Used for GSA/Manchester Air System - 4th-7th Floors

10

15

20

QLC: Zone cooling load

QLH: Zone heating load

QHCOIL: Heating coll load

OCCOIL: Cooling coll load

CFM: Airflow rate to the zone

CFMAX: Maximum fan capacity

CFMV: Outdoor air supply rate

CFMVO; Minimum outdoor air ventilation rate required

TASl: Supply air temperature during the normal cooling cycle

TAS2: Supply air temperature during the economizer cycle

WASl: Humidity ratio of the supply air during the normal cooling

cycle

WAS2 : Humidity ratio of the supply air during the economizer cycle

WA: Humidity ratio of outdoor air

WS': Humidity ratio of the air saturated at TASl

RAW: Humidity ratio of return air

RAT: Return air temperature

DB: Outdoor air temperature

DBX: Temperature of outdoor air leaving the exhaust-heat-recovery

heat exchanger

FTRS : Fan temperature rise

n: Heat-recovery heat-exchanger effectiveness

10
Computer Algorithms

a. IF QLC ^ 0 and QLH = 0

IF (CFM s CFMAX) CFM = CFMAX

Zone temperature is expected to rise above the set point

CFMR = CFM - CFMVO

10 TEST = CFMVO DB + CFMR -k RAT

CFM

CFMVO * WA + CFMR * RAW

^^^^ = CFM

QCCOIL = CFM A (1.1 * (TEST + FTRS - TASl) + 4.5 * 1061 * (TESW - WS)

15

IF CFMR ^ 0, CFMR = 0

The room temperature begins to decrease below the set point unless the heating coil is activated to provide

QHCOIL = 1.1 * (CFMVO - CFM') * (RAT - TASl)

20 b. IF QLC ?^ 0 QLH ^ 0

QCCOIL = 0

QHCOIL = QLH + 1.1 * CFMVO * (RAT - (DBX + FTRS))

when DBX = DB + n * (RAT - DB)

25 n = heat-recovery heat-exchanger effectiveness

11
IF economizer cycle is employed when

QLC > 0 and QLH = 0

The coll Is shut off when

DB ^ TAS2 - FTRS = TEST

' 1.1 * (rat'- IAS2)

'

IF (CFM ^ CFMAX), CFM = CFMAX

In this case the room temperature begins to rise above

the set point unless the system Is reverted to the normal

operation as described In (a).

IF CFMAX > CFM' > CFMVO,

the zone Is cooled by outdoor air and the zone humidity ratio

floats as determined by the balance between the room latent

load and 4.5 * CFMVO * (RAW - WA) * 1061.

If, however, CFM' < CFMVO

the zone temperature begins to decrease below the set point

unless the heating coll Is activated to provide

QHCOIL = 1.1 * (CFMVO - CFM') * (TEST - DB)

12
13
14
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GSA/MANCHESTER BUILDING

UPPER FOUR FLOORS

SOLAR HEATING SYSTEM ANALYSIS

Figure 9 Energy Balance for the Solar-Assisted Heating System

21
aH/nia 9oriN3iM3dino3d nand u31\oq
GSA/MANCHESTER BUILDING

UPPER FOUR FLOORS

SOLAR COOLING SYSTEM ANALYSIS

QF= FUEL

SOLAR COLLECTOR

EFFICIENCY « Eg

WASTE

HEAT

RECOVERY

EFFICIENCY

•Er

HEAT

STORAGE

200 "F

COEFFICIENT OF

PERFORMANCE -COPe

CHILLER

WATER

CAPACITY* QSTOR

ENGINE

GENERATORS

Y=E6

TO COOLINGCOIL LOAD

COIL

COEFFICIENT OF

PERFORMANCE eCOPa

QCOIL = QF- Eq' COPq + QF(I - Eq)- Ep • COPq

+ I - Eg- COPq -I- QSTOR • COPq

Q COIL- (I- E« + QSTOR) COR

Q . S fl. ^ EQ -COPe -H (I-EO Er COPq

ASSUMPTION Es^CALCULATED AS A FUNCTION OF I, AMBIENT

TEMPERATURE AND COLLECTOR TEMPERATURE

Eq = .28

Er « 0.5

COPj

COP.

3.0

0.6

Figure 11 Energy Balance for the Solar-Assisted Cooling System

23
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HH/niQ 901*031031100 1V3H dVHOS ONV QVOH HIOO

24
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FUEL REQUIREMENT

GSA/MANCHESTER BUILDING

UPPER FOUR FLOORS

SOLAR COLLECTOR

DOUBLE-GLAZE, SELECTIVE SURFACE

HEATING SEASON

SOUTH FACING AT 60* TILT

140 **F COLLECTOR TEMPERATURE (60»C)

COOLING SEASON

HORIZONTAL

220 *F COLLECTOR TEMPERATURE (I04.4»C)

HEAT STORAGE - 10,000 GALLON WATER

10 *»F TEMPERATURE CHANGE

(5.6»C)

I I I I I 6 8 10 12 14

COLLECTOR SIZE, 1000 ft^

16 18

Figure 13 Effect of Collector Size on the Energy Consumption for Heating and

Cooling of the Upper Four Floors in the GSA/Manchester Building

25
22

20

18

16

14

12

10

8 -

6 -

GSA/ MANCHESTER BUILDING (UPPER FOUR FLOORS)

SOLAR COLLECTOR

5000 FT2(460m^)

DOUBLE-GLAZE AND HORIZONTAL

220 *F TEMPERATURE FOR

. ABSORPTION CHILLER (104.4*0

1

I 2 3 4 5 6 7 8

NO OF STORAGE TANKS, 10,000 GALLONS/ TANK

10

Figure 14 Effect of Thermal Storage Size on the Energy Consumption

for Heating and Cooling of the Upper Four Floors in the

GSA/Manchester Building

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NBS-1 14A (REV. 7-73)

U.S. DEPT. OF COMM. BIBLIOGRAPHIC DATA

SHEET

1. IHUd.K A l lON OK KI.I'OKT NO. 2. Gov't Accession

riBSIR 7G-1056

4. TITLE AND SUBTITLE

Analysis of Solar Energy System for the GSA Demonstration

5. Publication Date March 1, 1976

6. Performing Organization ( odi'

7. AU rHOR(S)

T. Kusuda, S. T. Liu, J. W. Bean, and J. P. Barnett

8. Performing Organ. Report No.

9. PERFORMING ORG- AN IZAT ION NAME AND ADDRESS

NATIONAL BUREAU OF STANDARDS

DEPARTMENT OF COMMERCE

WASHINGTON, D.C. 20234

10. Project/Task/Work Unit No. 4624414

11. C^ontract /Grant No.

12. Spon.soring Organization Name and Complete Address (Street, City, State, ZIP)

Federal Energy Administration

New Post Office Building

12th and Pennsylvania Avenue, Washington, D.C. 20461

13. Type of Report & Period Covered Final Report

14. Sponsoring Agency Code

15. SUPPLEMENTARY NOTES

16. .ABSTRACT (A 200-word or less factual summary of most si^ificant information. If document includes a significant

bibliography or literature survey, mention it here.)

The energy conservation demonstration building of the General Services Administration

to be built in Manchester, New Hampshire, has been planned to be partially heated and

cooled by solar energy. Presented in this report are results of a study made at the

National Bureau of Standards to determine the effect of solar collector sizes and the

amount of storage on the overall energy consumption of the building. It was found that

the fuel savings attainable by the use of solar energy for heating and cooling of the

building will be less significant as the size of the collector and the amount of storage

are increased beyond certain limits.

17. KEY WORDS (six to twelve entries; alphabetical order; capitalize only the first letter of the first key word unless a proper name; separated by semicolons

)

Energy conservation; GSA/Manchester Building; solar collector;

solar heating and cooling; thermal storage

18. AVAILABILITY [X Unlimited 19. SECURITY CLASS

(THIS REPORT)

21. NO. OF PAGES

1 Eor Official Distribution. Do Not Release to NTIS

UNCLASSIFIED 34

r Order From Sup. of Doc, U.S. Government Printing

Washington, D.C. 20402. SD Cat. No. C13

Office 20. SECURITY CLASS

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22. Price

[XJ Order From National Technical Information Service

Springfield, Virginia 22I5I

(NTIS)

UNCLASSIFIED $4.00

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