NBSIR 75-711

Site Analysis and Field Instrumentation

for an Apartment Application of a

Total Energy Plant

John B. Coble and Paul R. Achenbach

National Bureau of Standards

Department of Commerce

Washington, D.C. 20234

May 1975

Final Report

Prepared for U.S. Department of Housing and Urban Development

Washington. D. C. 20410

NBSIR 75-711

SITE ANALYSIS AND FIELD INSTRUMENTATION

FOR AN APARTMENT APPLICATION OF A

TOTAL ENERGY PLANT

John B. Coble and Paul R. Achenbach

National Bureau of Standards

Department of Commerce

Washington, D.C. 20234

May 1975

Final Report

Prepared for

U.S. Department of Housing and Urban Development

Washington, D.C. 20410

U S, DEPARTWSEWT OF COfiflMERCE. Rogers C.B. Morton. Secretary

NATIONAL BUREAU OF STANDARDS, Richard W. Rol>arts. Director

TABLE OF CONTENTS

SITE MAIYSIS FOR THE APPLICATION OF 1 (First section)

TOTAL ENERGY SYSTEMS TO HOUSING DEVELOPMENTS

DESCRIPTION OF EQUIPMENT AND INSTRUMENTATION 1 (Second section)

FOR A FIELD STUDY OF A TOTAL ENERGY SYSTEM

IN AN APARTMENT DEVELOPMENT

SITE ANALYSIS FOR THE APPLICATION OF

TOTAL ENERGY SYSTEMS TO HOUSING DEVELOPMENTS

By

P. R. Achenbach and J. B. Coble

National Bureau of Standards

Washington, D. C. 20234

presented at

7th Intersociety Energy Conversion Engineering Conference

San Diego, California

September 25-29, 1972

SITE ANALYSIS FOR THE APPLICATION OF TOTAL ENERGY

SYSTEMS TO HOUSING DEVELOPMENTS

By

Paul R, Achenbach and John B. Coble

1. Introduction

Concurrent with the national effort to accelerate housing construction in the United States, there has been much concern about the continued

10 availability of some forms of energy used in housing and the effects of

energy use on environmental quality. Low reserves In electric generating

capacity and natural gas exist in many highly populated areas of the country

and the importation of oil is increasing rather sharply to meet growing

requirements.

15 These and other factors have caused the Department of Housing and

Urban Dt-velopment to utilize a part of their Operation BREAKTHROUGH housing

[iroHram for a field investigation of total energy systems as a means for

saving fuel and reducing pollution and for making the electrical services

independent of the local litllity system. Initiated In mid-1970, the

20 design and construction of about 2800 dwelling units on eleven sites in

the country to encourage industrialization and innovation in the homebuilding process. The National Bureau of Standards was requested to examine the feasibility of utilizing total energy systems for one or more of

these eleven sites to develop reliable data on thermal efficiency, daily

25 * A dwelling unit Is the housing facility for one family, Irrespective of the kind of building In which It is incorporated.

1
and seasonal load patterns, reliability and stability of the utility

services, the level of noise and pollution control, the maintenance and

repair requirements, and the ovming and operating cost. The number of

sites used for the BREAKTHROUGH program was later decreased to nine.

This program is a part of a broader program on utilities research being

carried out by the Utilities Technology Division in the Office of the

Assistant Secretary for Research and Technology of HUD.
2.0 Total Energy System Characteriatlca

?.l Definition

A total energy system is characterized by four principal concepts:

a) The electric energy for the developaent la generated on

site •

b) Waste heat from the electric generation equlpn»ent is

recovered and uaed on site for heating, cooling, or process functions.

c) The plant is located within the confines of the site being

served.

d) It serves a single building or a connnerclal. Industrial,

or residential site that is not traversed by public

thoroughfares.

The constraint on distribution of electric energy across public thoroughfares is a part of the franchise agree.Tients accorded to the electric

uti lities.

P . 2 System Loads

The principal loads on a total energy system in a residential application are: electricity for lighting, motors, and appliances; space

heating; space cooling, and domestic hot water heating. If there is

community development associated with the site there will be other types

of loads on the system that are characteristic of the particular facilities.

There are daily, weekly, and seasonal cycles to the four principal components of the load in a residential application of a total energy system.

Under favorable conditions the electric energy requirements and the

possible uses of the waste heat of a given application are so proportioned

3
chat Che cocal amount of energy utilized by the total energy system Is

significantly less than would occur if electric energy were taken from a

central utility system at a utilization efficiency of about 30 percent and

the ocher energy requirements were supplied by fuel-burning equipment at

the site. To the extent that this favorable balance of loads occurs,

there is good potential for lowering fuel usage and, in come cases, overall

annual cost for energy by utilizating a total energy system. Some capability

for auxiliary heating and for dumping unneeded heat is usually provided

in a total energy system. Certain types of loads from connercial or

community facilities help to improve the overall balance between electrical

demand and the demands for waste heat.

Corollary benefits sometimes claimed for total energy systems are:

greater reliability in electric service, conservation of energy resources,

and overall reduction in the discharge of heat and combustion products

Into Che environment.

2 . 3 Equipment Combinations

Total energy systems could be designed to utilize a variety of fuels;

however, nearly all systems now in operation uae natural gas, diesel fuel,

or a combination of gas and oil.

A total energy system can be made up of a wide variety of mechanical equipment assembled in various combinations. Internal or external

combustion engines or turbines can be used for driving electric generators

and air conditioning compressors. The latter equlpnent can be of either

the reciprocating, rotary, or centrifugal type. Absorption water chillers

can be used alone or in combination with compression water chillers to provide air conditioning. Space heating can be accomplished by electric
resistance heating or by circulating steam or hot water. Space heating

and cooling can be provided by heat pumps. Domestic water heating can be

done by utilizing waste heat and a heat exchanger, or by using gas, oil,

or electric energy directly as the heating source. Not all of these

equipment choices lend themselves to an efficient utilization of waste

heat or to attaining an optijnum relation between electric energy requirements and waste heat requirements in a total energy system when considering

the daily and seasonal load variations. Nevertheless, a number of

combinations should be evaluated in engineering and economic terms for

any given installation.

1/*

2

.

U Current Applications —

There are approximately 550 total energy plants in operation in

the United States at the present time ranging in size from 0.2 megawatts

to more than 20 megawatts. Installations of total energy plants began

about 1958 and reached a peak, in numbers of new plants installed, in 1967.

However, the total electrical capacity of new plants installed annually

has continued to rise. Total energy systems at present account for

approximately 0.2 to 0.32 of the electrical generating capacity of the

United States.

About 70X of the plants utilize reciprocating gas engines and an

additional 15% employ gas-fired turbines as the prime movers. The remainder utilize diesel engines, steam turbines, or dual-fuel engines

employing natural gas and fuel oil. A large majority of the total energy

systems serve industrial and cotimercial applications, with only about 5%

serving residential applications. At this time over 602 of existing

plants have less than ] megawatt generating capacity, but the plants installed in the last few years have averaged over 5 megawatts in capacity.

5

* See references at end of paper
A significant number^ of total energy plants have been deactivated in

recent years, with a high percentage of these having a capacity of 0.5

megawatt or less.

3.0 Site Ranking P arameters

Many factors have a bearing on the suitability of a housing development for the use of a total energy system. For the BREAKTHROUGH housing

sites, these parameters were separated into three groups having primarily

technical, administrative, and economic significance, respectively.

The parameters of a technical nature were: the number of dwelling

units and their density and arrangement on the site; the summer and winter

degre*^' days and the design temperatures at the site; and the method

of construction and assembly of the housing systems as related to the

ease in bringing the utilities into the houses. The administrative considerations were: the number of different housing systems to be built

on the site; the current and anticipated level of electric capacity

reserves applicable to the site; the amount and kind of community development to be provided on the site; the time schedule for beginning of

construction; ajnd the knowledge and interest of the site planner and site

developer in a pilot installation of a total energy system. The financial

parameters were: the relative cost of purchased electrical, gas and oil

energy at the site; the first cost difference between the total energy

system and the conventioneil system which it might replace; and the cost

of maintenance and repair.

Information was collectBd on the relative magnitude or importajice of

all of these paxameters for the six bPEAKTHPOUGH sites that appeared to

be better suited to total energy systems; namely, Jersey City, Memphis,

St. Louis, Macon, Sacramento, and Indianapolis. The other five sites at

6
WllmLngton, Houston, Kalamazoo, Seattle (2 tltea) were eliminated because

of the siT\aller number and lower density of the dwelling units on these

sites.

3.1 Number and Density of Dwelling Units

Several housing system producers are constructing groups of dwelling

units on each of the BREAKTHROUGH sites. The dwelling units on each site

are distributed among four basic types of construction: raultl-famlly

hlgh-r iseCMFHR) ; multi-family low-rise (MFLR); s Ing le- faml ly attached

(SFA); and s Ingle- faml ly detached (SFD). The six sites chosen for detailed consideration as experimental sites for total energy systems were

those with the higher numbers of dwelling units, since a total energy

system has usually been found to be uneconomical for developments of less

than about 200 dwelling units and for low density housing.

Table 1 shows the size of the BREAKTHROUGH sites at Jersey City,

Macon, Memphis, Indianapolis, St. Louis, and Sacramento, the total number

of dwelling units being built, and the percentage of each of the

several types of construction. The density of the housing ranges from a

maximum of about 77 dwelling units per acre at Jersey City to a minimum

of about 6 dwelling units per acre at Macon. For the six sites, the

dwelling units in high-rise buildings range from 12 to 98 percent of

the total. There are no s ingle- faml ly detached dwelling units on the

three smaller sites. Since a total energy system delivers energy-related

services from a central source, the unit cost of distribution is approximately proportional to the size of the site and inversely to the density

of the dwelling units on the site.
Table 1. Site Size and Dwelling Unit Distribution on

Six BREAKTHBOUGH Sites

Dwelling Unit Type. Z of Total

Site Acres

Tnt A 1 Units MFKR MFLP SFA SFD

Jersey City 6.35 488 98 2

Macon 50.0 287 20 23 52 5

Memphis 16.0 374 35 27 16

Indianapolis U2.9 287 12 5 U& 35

Sacrajnento 33.0 407 28 2U k2 6

St . Louis 't'^

' 15.5 kU 10 k6

3.2 Clitnatic Facto f

Since the economy of a toL«l energy system is dependent on making

use of Che waste heat from the engine-generator equipment used for electric power production, it is important that there be a reasonably steady

demand for the waste heat throughout the year. Thus a total energy system would not usually be economical in a residential application unless

some absorption air-conditioning Is used, because the heating of domestic

hot water may utilize less than one-third of the waste heat available

during the four or five warmest months of the year.

The climatic factors chat have a direct bearing on the economy and

capacity of a total energy system for a residential development are the

summer and winter outdoor design temperatures and the degree-days of

heacing and cooling for each sice. The significant weather data for the

six sices under consideration are shown in Table 2.

8

]
To K 1 a O r>-\

C. , I. i irriHL.ic ijaua icr oix

Site Winter Surmner

Deg're

days

e- Outdoor^

a

5/ Design - Temp. , °F J_/

Hours at

6T°F WB

or above ^/

Outdoor*^

Design

Temp.. °F

Jersey City I4902 15 1290

DB

s?

WB

lid Q_ UX 1 1 707 c 1 3UDy 96 79

Memphis 3006 21 2631 96 79

Indianapolis 5611 U II462 91 77

St, Louis 11 1866 9U 78

Sacramento 2822 32 351 97 70

Based on an indoor temperature of 65°F.

Based on . 97 1/?X ^ f winter hours being .^t or above this temperature

Based on 2 1/2J of summer hours being at or above these temp.

In cooler climates the size of the supplemental boiler will likely

be determined by the maximum winter heating load, whereas In warmer

climates the size of the supplemental boiler may be determined by the

maximum cooling load, If absorption cooling Is used. In warm and humid

climates the number of hours during the summer when the outdoor wet-bulb

temperature Is at or above 67 'F Is a good Indicator of the amount of

time that air conditioning will be required, but In hot and dry climates

a dry-bulb temperature criterion Is more reliable.
10

15

20

25

3.3 Analysis of Energy Usage

3.3.1 Space Heating and Cooling Loads

Calculations were made of the expected loads for space heating

and cooling, domestic water heating, and miscellaneous electrical uses at

each of the six BREAKTHROUGH sites. This infornation was needed to determine the approximate size of the total energy plants, the applicable

energy rate schedules, the availability of appropriate system components,

the differential in first costs, and the amount of space needed for the

plant on the site. At the time of these calculations, the materials of

construction, the size of each type of dwelling unit, and the number of

each size of dwelling unit were known.

The gross monthly energy requirement for space heating and cooling

and the maximum monthly energy demand rate were calculated for each site

using the following procedures:

Monthly Heating Energy Requirement, Btu -

Monthly Heating Degree-Days x KHL^ X A^ (1)

2 HL^ iH the heat transmission for a type i building in Btu/ (ft

floor area) (degree-day). This quantity was calculated by a computer

program using a transfer function technique to determine the dynamic response

of the building to the total environment (temperature, wind, solar radiation,

orientation, internal loads, etc.) The quantity HL^ was determined for

five different types of buildings; namely, multi-family high-rise, multifamily low-rise, single-family attached, single-family detached, and nonresidential. The non-residential classification Included conmerclal

buildings, school buildings, plant and public spaces.

10
l9 Che total floor area of each type of building in the development,

Monthly Cooling Fnergy Requirement, Btu •

Monthly Cooling Degree-Days x KCL^ x A^) (2)

CL^ was determined for each type of building using the computer technique

that was used for calculating HL^.

Maximum Monthly Heating Load Demand, Btu/hr "

(75 - ''^min)

(3)

10 HD^ is the maximum heating demand determined for the different building

types in the Jersey City site for a steady outdoor temperature of II which

2 is the 997, design temperature for Newark, N.J., expressed in Btu/(hr)(ft ).

The maximum monthly heating load demand calculated by equation (3) and

the maximum monthly cooling load demand calculated by equation (4) vere

^5 normalized on Jersey City because extensive calculations of the demands by

the buildings for the Jersey City site had been carried out.

^mln 30-year average of the minimum dally temperature for

the month and the site being considered.

The maximum monthly heating load demand was taken as lero, if equation

20 (3) yielded a negative value.

Maximum Monthly Cooling Load Demand, Btu/hr -

y Tmax - 75 )

( 91 - 75 ) I (CDj X Aj) (^)

CD^ was calculated similarly to HDj based on data for Jersey City

25 buildings and a maximum daily temperature of 91*F.

11
max is Che maxlauai d«lly temperature (baaed on a 30~year average) for

the month and site being considered.

The maximum monthly cooling load demand waa taken as zero, if

equation 4 resulted in a negative value.

5

:

3 „ 3 . 2 Electricity and Domeitlc Hot Water Uaage

6 7 8 9/ Published information—« » » on the usage of electricity for domestic

hot water and for miscellaneous purposes dwelling units In the United

States was used as the basis for estimating these energy requirements

10 at the various BREAKTHROUGH sites. From these sources it was estimated

that the monthly electrical usage per dwelling unit for miscellaneous

purposes would be 702 kiloMtt hours and the daily usage of hot wttter

would average 41 gallons per day. These estimates take into account the

observed 67* annual increase in electrical use since the data were collected.

15 The average hot water usage was adjusted for the storage losses. Monthly

variations in electricity and domestic hot water usage were adjusted to

agree with observations shown in the published reports referenced above.

20

25

12
3.3.3 Energy System Simu l ation

The overall energy requirement for a given housing development is

different for different types of energy utilization systems. Considered

In this analysis were seven different systems; three were different

types of total energy systems, two were all-electric systems, and two were

conventional systems.

An a 1

1 -absorpt ion air-conditioning system was assumed for one of the

total energy systems, engine-driven centrifugal compressors were assumed

for a second, and varying combinations of absorption and engine-driven

compression air conditioning were assumed for the third. Other components

were identical. One all-electric system used resistance heaters for

space heating and motor-driven compression air conditioning; the other

(ised Individual alr-to-alr heat pumps In each dwelling unit for year-round

space conditioning. The two conventional systems utilized electric

energy from the municipal system and fossil fuel for heating functions.

One conventional system used a 1 1 -absorpt ion air conditioning and the

other motor-driven compressors for air conditioning.

A computer program was prepared to calculate the monthly and annual

energy usage for each of the seven energy systems described above for

the BREAKTHROUGH sites at Jersey City, Macon, Memphis, Indianapolis,

Sacramento, and St. Louis. The equipment efficiencies and performance

factors used in these computations were as follows:

13
Engine-Generator Efficiency .Total Energy Plant, Z 25

Central Generating Plant Efficiency. (point of use) Z 29

Waste Heat Recovery. Z of Available 67

Boiler Efficiency, 2 70

Absorption Chiller Coefficient of Performance 0.67

Centrifugal Chiller Coefficient of Performance 4.0

Engine -Compreasor Efficiency, Z 30

Individual Heat Pump Coefficient of Performance 2.3

Plant and Building Auxiliary Electric Load,

for Jersey City, KW Winter 443

Suoner 665

Table 3 shows the calculated energy requirements for the several

different energy utilization systems. Four different combinations of

absorption and compression air conditioning equipment were evaluated for

the total energy concept, in addition to all-absorption and all-coapres*'

slon air-conditioning systems.

Table 3 shows that the total energy system using all-absorption

air conditioning had the lowest overall energy requirement at Jersey City,

whereas a combination of 40Z absorption and 60Z compression air conditioning in a total energy plant was most economical in energy use at four of

the other sites. It is believed that the electrical energy requirements

for the commercial and school areas and the electrical auxiliaries (pumps,

blowers, etc.) in the total energy plant raised the level of available

waste heat at the Jersey City site sufficiently to satisfy a high percentage

of the thermal energy requirement of the absorption air conditioning system,

thus making absorption cooling the best alternative at this site.

14
The most economical total energy plant saved from 28 to 40 percent

of the energy required for a conventional syttem using absorption chiller

for air conditioning at the several sites. It was assumed that electrical energy was purchased from the local electric utility system in the

conventional plants.

15

3. 4 F. nergy Costs

Knergy cost Information for the six BREAKTHROUGH sites was obtained

from the latest published schedules for gas and electricity and from

quotations of local fuel oil dealers, as of April 1972. In each location

the electric and gas utilities have established several rate schedules

which apply to different residential, commercial, and industrial loads.

For computing the monthly and annual energy costs at each site, those

rate schedules which provided the lowest cost for energy and which were

applicable to the particular utility system under consideration were used.

The rate information for gas, oil and electricity is sunmarized

in Table 4. For each kind of energy, the costs cited include both the

demand change and the energy consumption charges. For fuel oll^the

unit cost is not dependent on the amount consumed when the fuel is

delivered in bulk lots to the central utility plant.

Separate electrical energy costs are shown in Table 4 for single

metering of all energy used in the development and for individual

metering of the electrical energy used in each dwelling unit for three

different energy systems; namely, heating and cooling with a heat pump

In each dwelling, electrical resistance heating and a unitary air

conditioner in each dwelling, and a fuel-fired heating unit and unitary

air conditioner in each building. The range of unit electrical energy

costs shown in each block of Table 4 covers the variations in monthly

use throughout the 12 months of the year.

The costs shown In Table 4 represent a significant increase in

comparison with those available in August, 1970, when the feasibility

study was first made. Oil prices have increased an average of about

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7 percent in Che six cicles, ranging from no increase in Macon to IIZ

in St. Louis and Sacramento. The cost of gas has increased an average of

22% in five of the cities, not including Macon, where the increase has

been 104% in two years. This unusally large increase in Macon is largely

due to the termination of a very favorable incentive-type schedule that

was in effect when the previous Infomatlon was collected in August*

1970. :

The cost of electricity has increased from 30 to 40 percent at

Jersey City, Indianapolis, St. Louis, and Sacramento during the last two

years for large loads exceeding one million kilowatt-hours per aonth. The

increases were even larger in Macon and Meaphis, approxiaately 60X and

lOOZ respectively, for a similar load range. The increases in lower

load ranges are of the same order of magnitude.

The annual energy requirements shown in Table 3 and the unit

energy and fuel costs sbpvm in Table 4 for the different types of service

at the six sites were used to calculate annual energy costs for each of the

different utility systems. These annual energy costs are shown in Table 5

for six different equipment combinations In a total energy plant and for

both oil and gas. For the all-electric systems and the conventional

systems using a combination of fossil fuel and purchased electricity it was assumed that all of the electrical energy was metered by one aster.

Table 5 shows that oil was the more economical fuel at Jersey

City and Macon, and gas was more economical at the other four sites for

both the total energy and conventional systems. The most economical total

energy system at each site saved from 25 to 60 percent of the energy cost

for the comparable conventional plant uaing motor-driven compression cooling

20
and from 30 to 59 percent of the energy cost for the comparable convcntiona

plant using absorption cooling. The calculated cost saving at Jersey City

wa ilic lowest of thv six s i to s , because coimnercially produced electricity

' and oil are more competitively priced in Jersey City than at the other

si tes

.

3.5 Ovming and Operating Costs

Precise determination of typical owning and operating costs for

utility systems is difficult to develop at present because the costs of

machinery, materials, fuel, and labor are all changing rather rapidly.

At any given time the costs of gas and electricity are published, but

new schedules are appearing at irregular intervals so future costs will

change accordingly.

The first costs for the total energy system at Jersey City are

summarized In Table 6. There is some \jncertainty in the figure cited for

the cost of the building since it will house both the total energy system

and the solid waste collection, compacting, and loading system. Half of

the total building cost was allocated to the total energy system in Table 6.

The design and construction management costs are relatively high

for the Jersey City installation for a number of reasons, including the

following:

a) Coordination of the plans for at least four different building

types^

b) Redesign of some of the buildings and changes in housing

system producers,

c) Incorporation of an innovative waste disposal system on the site

d) Provision for installation of data collection equipment and for

21
field experimentation on both the total energy systen and the

solid waste disposal system,

e) Provision of more standby electric-generating equipment

than typical and provision of some additional space for future

Installation of innovative components.

The cost data in Table 6 show that the investment cost for the

total energy system will be about $A,900 per dwelling unit, if the cost

is pro-rated between the residential area and conntercial facilities in

proportion to floor area. The overall investment cost for providing the

on-site generating facility is estimated at $720,000 or $240 per kilowatt

of installed capacity. This figure includes the purchase cost of the

engine-generators and controls and pro-rated costs for system design,

equipment building, installation costs, and construction management costs.

This value of cost per kilowatt of Installed capacity can be used for

estimating first cost differences between a total energy system and a

conventional central heating and cooling plant at the five other BREAKTHROUGH sites under consideration, since they are all similar in size.

Sufficient data on the cost of maintenance and service costs for

total energy systems are not available to cite a reliable average value.

However, a limited number of published reports indicate that contracts

for maintenance and service of engine-generators, with either turbine or

reciprocating engine drive, are in the range of 0.3 to 0.4 cent per

kilowatt hour of energy produced. The annual contract cost of maintenance

and service for heating and cooling equipment is in the range from $20 to

$30 per ton of installed refrigeration capacity. These figures apply to

plants in the size range needed for the BREAKTHROUGH housing sites.

22

I -I
Table 6

Costs of Total Energy Systen at

Jersey City, Nev Jersey

Purchase Cost

Engine-Oenerators $315,000

Generator Controls 91,000

Cooling Towers 57,000

Central Equipment Building, Prorated 2U9,000

Construction, Total Energy Plant,

including purchase of heating/cooling

equipment r,093,000

Subtotal 1,805,000

Utility Distribution System 367,000

Design and Management Costs

Total Energy System 125,000

Site Utilities 1^41,000

Central Equipment Building 57,000

Construction and Contract Management 175,000

r.ubtotal 1*98,000

Overall Total Cost 2,670,000

23
3 . 6 Adaptability of Housing Systems to Total Energy

Nineteen of the twenty-two houaing system producers will be building

dwelling units on the six BREAKTHROUGH sites under consideration in this

report. The number of different systems on one site ranges from three on

the Jersey City and Memphis sites to eight on the Indieuiapolis site.

Constructions that provide cavity walls or sandwich constructions

made of wood, foamed insulation, gypsum board emd other materials that

can be readily cut provide the greatest flexibility in introducing conduits and ducts into the structure. Constructions of masonry and concrete

panels that provide for pipe chases at the Joints offer an intermediate

level of flexibility for conduits for electricity, water and drainage systems. Factory prefabricated volumetric modules must in most cases incorporate a completely preplanned arrangement of service systems, especially

if made of masonry.

Every dwelling unit must provide for distribution of electricity and

domestic hot and cold water ; and for an adequate drain, waste, and vent

system, whether the site is equipped with a total energy system, central or

individual heating and cooling systems. If Individual heating and cooling

units are used, electricity and gas or oil must be brought to this equipment. If a total energy system or a central hot -and-chi lied water system

provides for space conditioning, two to four water pipes of relatively

small size and electric service must be brought to the central unit in

each house. These additional pipes (one to three) can readily be accommodated in cavity walls, pipe chases at panel Joints, or in the special utility

chases that must be p-ovided in volumetric module housing designs. Thus

the adaptation of the total energy concept to the variety of proposed

24
housing systems does not appear to offer any new or major type of design

problem.

3. 7 Conmunlty Development

The addition of retail stores and certain types of community

development to the load on a total energy system is usually considered to be

advantageous because it raises Che electrical load factor of the system

and permits a larger fraction of the thermal energy requirements of the

development to be provided from recovered waste heat.

Only the Jersey City and Macon developnents incorporated any retail

facilities, with the Jersey City floor area being larger by a factor of at

least five. The community facilities planned for the Jersey City site are

as follows:

Retail stores 45000 sq ft

Schools 19500 "

"

Swinming pool 5000 " "

Public Spaces 3000 "

"

Community Center 2500 "

"

lie rpsldentlal floor area planned for the Jersey City site totals

jOH.OOO square feet.

) . 8 Fnvl ronmental Factors

An analysis was made of the characteristics of a total energy system with respect to thennal environment, noise and vibration inside the

plant; the transmission of noise and vibration to the surrounding occupied

space; and the likelihood of creating unacceptable air pollution in the

commun I ty

.

Visits to several installations of total energy systems indicated

that noise and vibration control was essential in a residential conmunlty.

Excessive noise and vibration transmission from a total energy plant can

25
occur by direct transmission of engine room noise through windows, lightweight walls, and engine room ventilation ducts; from the pulsating exhaust

of reciprocating engines; from air or water flow in the cooling tower; and

by transmission of vibration through the foundations of reciprocating or

rotating machinery to surrounding buildings. All of these features of noise

and vibration control require specific attention in the design of the plant,

but none is an insunaountable problem.

Federal, state, and municipal limitations on the amount of

particulates and sulfur dioxide that may be discharged into the atmosphere

with combustion gases essentially dictate the use of gas or No. 2 fuel oil

in residential areas. The problems of fuel storage, ash handling, and

particulate and aulfur dioxide discharge make it impractical to use coal

in a total energy plant on a BREAKTHROUGH site. Combustion gases from a

gas- or oil-burning plant must be discharged at a height that will promote

diffusion into the upper atmosphere and at a location that will not allow

the prevailing winds to carry them Into nearby dwellings, recreation areas,

or other occupied spaces. Likewise, the water vapor emanating from the

cooling tower should not create objectionable mist, fog, or frost deposits

In occupied areas or traffic areas of the site. These latter problems

related to discharge of combustion gases and water vapor dissipation are

no different for a total energy plant than for a conventional central

heating and air conditioning plant.

3 . 9 Energy Resources

There are inadequate reserves of electric power generating capacity

In wide areas of the United States. Especially critical are the eastern

•eaboard states from New York to Florida and the cities of ChicagOs, St.

26
Louis, Minneapolis, and St. Paul.— The electrical power shortage emphasizes

the relevance of a study of alternative utility options for new housing

developments. Concurrently, there are shortagas of natural gas. In Baltimore

no new Industrial customer can obtain natural gas service if his requirements

exceed 300,000 cu ft per day, and no current customer can increase his requirements by more than 300,000 cu ft per day, whereas in Washington, D.C.

no new customers can be connected at all. The importation of gas from

Algeria and Canada is being implemented, but is not expected to meet the

growing demand.

Because of Insufficient reserve generating capacity In several areas of

the ..ountry, the application of total energy systems to the BREAKTHROUGH sites

In Jersey City, St. Louis .Memphis , and Macon may serve as good and prudent

examples of conservation of scarce resources in these particular areas as

well as worthwhile experiments for wider consideration. The gas qtility

serving Jersey City Is not able to furnish gas for a total energy plant at

that site. Since fuel oil Is a little cheaper than gas In Jersey City at the

present time, and because New Jersey is near the end of the gas distribution

pipeline from the Texas fields, Jersey City would be a good choice for an

experimental oll-burnlng total energy system. There appear to be adequate

gas reserves at Macon, Memphis, and St. Louis for the BREAKTHROUGH sites.

3 . 10 Site P lanner and Developer Attitudes toward Total Energy Systems

The site planner and developer for the Macon site have sho%m the

greatest initiative and Interest in the application of a total energy system

to the BRF^KTHROUGH development. In fact, the planner proposed that they

be authorized to make a feasibility study, produce a design, and carry out

field studies of performance after Installation.

27
The site planner for the Jersey City site expressed a positive

attitude about a total energy system there, and vas encouraged and supported in this approach by one of the housing systeia producers. This

producer envisions replacing an Initial fuel-burning total energy system

in a fev years with fuel cells as a direct aeans for converting cheaicGil

energy into electricity. Fuel cells are not sufficiently developed as

The site planner at St. Louis was villlng to consider the installation of a total energy system provided it did not entail higher capital

costs for the developer and did not delay the time schedule. RouaeWates, the only housing system producer on the eastern parcel of the St.

Louis site, had a feasibility study of total energy and several other

utility systems made to determine economic feasibility. That study

and a second study of the economic feasibility of a total energy plant on

t|» Rouse-Wates development reached contradictory conclusions.

The planners and developers at the Memphis, Sacramento, and Indianapolis sites took no initiative in exploring or promoting application of

total energy systems to their respective developments.

28
U . Recommendattona and Impletncntatlon

When the feasibility study was made two jears ago, none of the BREAKTHROUGH sites were under construction and the types of buildings, the

materials to be used, and the housing systea producers were in an early

3 stage of identification. The sites at Memphis and Jersey City were

recommended as the two best sites for a total energy plant, partly because

they would have the largest number of dwelling units, a high density

of dwelling units, and more high-rise construction than the other sites.

Jersey City was given preference because it was to have the only large

10 amount of commercial development, and because the planner and one of the

housing system producers were interested in the use of a total energy

system. Jersay City did not then have a particularly favorable ratio between

the costs of fossil fuels and electricity.

As the design and construction of the various BREAKTHROUGH sites

15 have developed, the number of dwelling units at Memphis has been reduced

by 21 percent and the percentage of high-rise units has been lowered from

61 to whereas the percentage of high-rise units at Jersey City has

risen from 43 to 98.

The coats of all fuels have risen significantly since mid-1970. The

20 price of electricity has risen more than that of oil and gas, and the

price of oil has risen the least 10 percent or less in the six cities

considered in this study. Gas was not available in Jersey City for a

total energy plant so the plant has been designed for oil. The ratio of

prices between oil and electricity in Jersey City has become more favorable

to the installation of a total energy plant during the last two years.

29
Th« houolng and Ch« total •a«rgy plant at tha Jaraey City alte

ara undar cooatruction at tha praaant tlaa and occupancy la expactad for

tha aprlng of oaxt yaar. Anothar papar In thia confaranca deacclbea

tha datalla of tha flald atiidlaa that will ba aada on thla slta and the

Inatruaentatlon to ba ucad for gatharlng parforaanca data.

30
5. References

1. Totel Energy, Directory and Date Book, Vol. 9, No. 1, Jen,, 1972.

2. Nev>e Itene, Gae Coopecltlon, Southern Service*, Inc., Blrvlnghaa,

Alabama, Jan., Feb., March, 1970.

3. ASHRAE Handbook of Pundaaentali , Chap. 22, 1967.

4. Engineering Weather Data, Air Force, Army, and Navy Manual, APM-88-8,

Chapter 6, NAVFAC, p. 89, July, 1967.

5. Monthly Normal Teoperaturee, Precipitation, and Degree Daya, Technical

Paper No. 31, U.S. Weather Bureau, Nov. 1956.

6. An Integrated Utility System Concept, Robert V. Ayres, et al, IRT-N-95,

International Research and Technology Corp., Washington, ^.C. April,

1970.

7. An Analysis of Electric Energy Usage In Air Force Houses Equipped with

Alr-to-Alr Heat Pumps, Paul R. Achenbach, Joseph C. Davis and

William T. Smith, Monograph 31, National Bureau of Standards,

Washington, D. C., 1962.

8. Residential Energy Consumption, Hlttman Associates, 1972.

9. ASHRAE Guide and Data Book, Systems Volume, 1970.

10. Warning: Low Voltage, Ne^s'-eek, May 18, 1970.

31

DESCRIPTION OF EQUIPMENT AND INSTRUMENTATION FOR A

FIELD STUDY OF A TOTAL ENERGY SYSTEM IN AN APARTMENT DEVELOPMENT

By

J. B. Coble and P. R. Achenbach

National Bureau of Standards

Washington, D. C. 20234

presented at

7th Intersociety Energy Conversion Engineering Conference

San Diego, California

September 25-29, 1972

DESCRIPTION OF EQUimENT AND INSTRUMENTATION FOR A FIELD

STUDY OF A TOTAL ENERGY SYSTEM IN AN APARTMENT DEVELOIHENT

By

John B, Coble and Paul R, Achenbach

ABSTRACT

The Department of Housing and Urban Development selected the BREAKTHROUGH site at Jersey City, N. J, as the location for an installation and

field study of a total energy system. This development covers six acres,

and is comprised of four buildings containing 488 dwelling units, a small

building for commercial use, two small schools, a swimming pool, and the

total energy plant. The field study of this installation

is being carried out by the National Bureau of Standards to produce muchneeded authoritative information on engineering performance, maintenance

requirements, and load-and-cost data for total energy systems.

The central plant and the individual buildings are being extensively

instrumented to provide digital data on fuel utilization, the generation

of electrical and thermal energy, the excess heat rejected, and the utilization of electrical and thermal energy by all major segments of the load,

A separate analog data system is being employed to obtain recordings of

transient conditions of voltage, frequency, current, power factor, and

load division during sudden load changes and to record interruptions of

service due to overload or malfunction of equipment. The environmental

impact of the total energy plant with respect to noise, vibration, air pollution, and aesthetics is also being evaluated.

KEY WORDS: data acquisition system; electrical power system; energy

conservation; fuel utilization; thermal efficiency; thermal energy system;

total energy system; utility system performance; waste heat recovery.
V
DESCRIPTION OF FQUIPMENT AND INSTRUMENTATION FOR A FIELD

STUDY OF A TOTAL ENERGY SYSTEM IN AN APARTMENT DEVELOPMENT

By

John B. Coble and Paul R. Achenbach

1 . Introduction

This paper describes the program that will be conducted by the

National 3ureau of Standards, under sponsorship of the Department of Housing

and Urban Development (HUD), for analyzing the performance of a 3 megawatt

total energy system on the Operation BREAKTHROUGH site at Jersey City, N. J.

On this six-acre site, electricity and energy for heating and cooling will

be produced by a central plant using number two fuel oil In dlesel engine10

generators and boilers. The site has 488 residential dwelling units in

four medium- and high-rise buildings. Also on the site are a school, preschool, commercial areas and a swimming pool. The National Bureau of

Standards Is Installing an extensive data-collection system to analyze the

electrical and thermal performance of the total energy plant and the energy

use by the buildings of the development.

When the National Bureau of Standards started this progrsm In April,

1970, very little data on the economic and engineering aspects of total

energy systems had been published. Most total energy systems were In20 stalled In areas where the price of natural gas was low enough relative

to the cvjjL u f electricity to make such a system attractive to the client.

Many systems were operated by the maintenance staffs of the local gas utilities. Since the majority of these plants have less than one megawatt installed capacity, only enough Instrumentation was Installed for operational

25 purposes. In most cases, the Instrumentation was Inadequate for an engineering determination of thermal efficiency, load diversity, and reliability,

I
The continuing depletion of gas reserves and the widespread shortage

of reserve electrical generating capacity in the United States made it

highly desirable to determine the potential of a total energy systen for

providing reliable thermal and electrical utility service to new developments with lower usage of fuel. Consideration was given to the instrumentation of an existing total energy plant for this study. However, it would

have been difficult to place the flowmeters, temperature sensors, and electrical instruments into an existing system. Furthermore, such a study would

have constituted an after-the-fact determination and disclosure of the engineering, economic, reliability, environmental, and maintenance aspects

of a system not designed in response to a performance specification and

not intended for such detailed analysis.

By contrast, the BREAKTHROUGH program of the Department of Housing

and Urban Development offered an opportunity to analyze widely distributed

sites for their suitability for a demonstration plant. The financial and

management guidelines for the BREAKTHROUGH program also provided considerable latitude in specifying the desired performance of the system and the

degree to which it would be instrumented and evaluated.

After feasibility studies of eleven BREAKTHROUGH sites for the installation of a total energy plant had been completed, and the Jersey City

site had been selected, a performance specification for the plant was

prepared. This specification set forth. In performance language, the

requirements for the plant with respect to load determination, standby

capacity, system reliability, stability of electrical services, maintenance, safety, and its environmental Impact in terms of noise, vibration,

air pollution, magnetic interference suppression, and aesthetic

2
treatment. Ihis performance specification became a part of the guideline

documents for the engineering firm, "Gamze-Korobkln-Caloger", which then

designed the demonstration plant. The feasibility study Is described In

another paper 'being presented at this conference.

It was decided that the Jersey City BREAKTHROUGH site would also be

used for a demonstration installation of a pneumatic trash collection

system (PTC) sometimes also called a vacuum solid waste collection system.

This system was designed by another firm using a separate specification

and is the subject of another paper. However, the solid waste collection,

compaction, and loading equipment will be combined with the total energy

plant in a single central equipment building. Figure 1 shows the locations

of the boilers, chillers, engine-generators and the pneumatic trash collection

system in the central equipment building, which Is approximately 50 feet

by 1A3 feet In size.

2. Site Utility System

All electrical and thermal energy for the Jersey City site will be

produced on site. The electricity will be generated by dlesel-englne-drlven •

generators. Hot water for space heating and domestic hot water

will be produced by recoverable waste heat from the engine-generators and

by two supplementary boilers. During x.)ie ai r-condltlonlng season, hot

water will be used in absorption refrigeration machines to produce chilled

water. The electricity, hedtlng hot water and chilled water will be

distributed to the buildings on the site through underground conduits.

Ftgure 2, a schematic of the site, sliows the location of the electrical,

chilled and hot water, and penumatic trash collection systems.


Hie central pneumatic trash collection system will pull all

trash from the site into a single compac tor- type receptacle In the

central equipment building.

Electricity at 480 volts, 60 hertz, three-phase, will be distributed

from the total energy plant to each building.

6
2.1 Engine-Genera tora

The central utility building will contain five 600-KW engine generators,

each rated 480 volts, three-phase, 60 hertz, 750 KVA at 0.8 p.f. The engines

are rated at 860 HP and are designed for ebullient cooling. Hovever, the

5 engines will be water-cooled, and are designed for a flow rat« of 300 gpm

of primary hot water entering the Jackets at 225°F and leaving at 236"?

under full load conditions. About 43Z of this water (130 gpm) will be /

circulated through the exhaust heat recovery muffler, where it will be

heated' from 236'F to 252'F. The water leaving the heat recovery muffler

10 will be mixed with the remaining Jacket water and will enter the primary

hot water loop at about 241°F. Figure 3 shows the primary hot water system

in the central utility plant.

During the wannest and coldest months of the year, the heat

recovered from the engine-generators will provide from AO to 50Z of the

15 total thermal requirements, while the remainder will be supplied by the boilers.

2.2 Boilers

Two boilers, each rated at 13,390,000 Btu/hr, will supply all of the

heat not obtainable from the engine-generator recovery system. The boilers

will be Installed In series with each other and with the engine jacket

20 water circuit, as shown in Figure 3 and are used to "top off" the primary

hot water temperature. The control system senses the chiller and hot

water heat exchanger loads to maintain the primary hot water in the range

from 225°F to 245°F. During periods of low hot water usage, the boilers

will not be used If enough heat is provided by the heat recovery system

25 on the engines.

7

2 . 3 Absorption Chillers

Two 526-ton absorption chillers will provide chilled water for air

conditioning of the entire site.

The absorption chillers are to be installed in parallel. The chilled

water control system controls the operation of the chillers as the load

demands. Each chiller requires 826 gpm of primary hot water entering at

245°F and leaving at 222°F to produce 936 gpm of chiller water leaving

at 44°F and returning at 58°F under full load conditions. The chillers

require a constant volume of primary hot water and will use a 3-way valve

to modulate the hot water teaperaturc during lov loAds

.

2. 4 Dry Coolers and Heat Dump

When one or more engine-generators are operating to satisfy the electrical requirements and there is little need for either space heating or

cooling, the return water to the engine Jackets may become too hot for safe

engine operation. Two dry coolers (water to air heat exchangers) connected

in parallel, have been provided in the design to dispose of excess heat.

These dry coolers will be mounted on the roof and are equipped with fans

that operate whenever the return water entering the engine jackets reaches

a temperature of 230°F. If, for any reason, the fans in the dry coolers

fall to operate, a second set of heat exchangers (heat dump) cooled by

city water, will be activated when the return jacket water reaches a

temperature of 235°F.

2 . 5 Electrical Distribution System

Electricity will be distributed by a three-wire delta system with

two separate feeders serving each building on the site. One feeder, labeled

a normal load feeder (PN) , will supply electricity for the individual

9
dwelling units, miscellaneous power, and for all elevators except one

in each building. The second feeder, labeled an essential load feeder

(PE), will supply power for the corridor and stairway lighting, one

elevator in each building, heating and cooling water pumps, sump pxxmpa t

3 domestic water pumps, and fire pumps. The sump pumps, heating and cooling

water pumps, and domestic water pumps, will be electrically interlocked

with the fire pumps to limit the demand on the distribution and generation

system.

Three motor control centers (MCC) and one lighting power circuit

10 (LP 1 ) will furnish all of the electric power for the auxiliaries and

lighting requirements of the central equipment building. A separate

feeder (PTC) will furnish electric power to the pneumatic trash collection

system in the central equipment building (See Figure 4)

.

The circuit connecting the total energy system to the municipal

15 power system will normally be open. This switch, illustrated in Figure U,

will be closed in case all of the five engine-generators are Inoperative

and have been shut down. Only enough power would be taken fvom the

mvmicipal system to serve the essential load circuits on the site.

3. Data Collection System

20 The total energy system at Jersey City is being extensively instrumented to produce engineering, reliability, maintenance, and load-and-cost data

that are not generally available at the present tine. It is anticipated

that the data collected from this installation can be reliably extrapolated

to larger housing developments, other climates, other fuel cost situations,

25 and some other building occupancies.

10
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The Instrumentation being installed will provide for detailed analysis

of the fuel used, the electrical and thermal energy generated, the utilization

of energy by all major segments of the load, the perfonnance of all major

plant components, the stability of the electrical service, the reliability

5 of the several services, maintenance requirements, environmental conditions

in and near the plant, fuel and operating costs, and weather data. The

target end-to-end accuracy for this measurement system is 12 which means

that the individual transducers need to have accuracies on the order of

0.1% to 0.25%. This level of accuracy is Important because of the large

10 number of integrated measurements of energy use that are required.

The data collection system is comprised of two major components;

namely, - /

a) a central data logging system that will scan, transmit, and

record 300 channels of data on magnetic tape every five minutes. This

15 system collects data directly from the central plant and via satellite

units from each of the buildings on the site. The satellite units transmit data on electrical and thermal energy usage to the central data

logging system.

b) an analog system consisting of a strip chart data logger to

20 record transient variations in the electrical service, interruptions of

the utility services, and malfunctions or overloads on the system.

3. 1 Central Data Logging System

The central data logging system is Installed in the central utility

building. It scans and records the 300 data channels in the power plant

25 at a rate of up to 30 channels per second. The components of the central

data logging system are shown on Figure 5. The central controller directs
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system operation including sequencing of channels for Bcan, scan rate,

analog -to -digital conversion, etc. The master scanner output of the

central controller Is printed every five minutes on magnetic tape or

optionally on a manually-controlled teletype printout.

In sequence and as part of each central utility plant scan, the

central data logging system controls the satellite units so that the data

channels in each building are recorded on the central data logging system.

The satellite units do not record data. On signal from the central controller they scan the electrical and water flow meters and the temperature

sensors in each building every five minutes. The actual data retrieval

requires only about one second per building. Thirteen channels of data

are to be recorded, but the system is expandable to 30 channels per building.

Figure 6 shows a schematic of the typical electrical and piping

system, including data collection instrumentation in each building. The

data collection system is designed to measure and record Integrated

electrical energy usage and instantaneous readouts of the flow rates and temperatures of chilled water, heatlna hot water, and domestic hot water in each

building.

3.1.1 Electrical Metering

Figure 4, a one-line diagram of the electrical distribution system

in the central utility plant also shows the location of the electrical

metering points in the central equipment building. On both the normal

PNl-to-PN5 and essential PEl and PE2 load feeders, energy usage will be

measured and recorded every five minutes in the individual buildings.

The instantaneous electrical power will be measured by a "Hall

effect" watt transducer, and the energy use will be integrated by an

auxiliary device being designed and built at the National Bureau of

Standards. The wattmeters are to be installed on the 208-volt four-wire

(WYE) side of the building transformers.

14
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LEGEND: TW - thermocouple, aP . Differential Pressure/, transmitter'

^IT - Differential (Thermopile) Temperature, V - Venturi

Vt- Voltage

Fig. fe A schematic drawing ot the instrumentation in the inoividual buildings

for determining the thermal and tlectrical energy usage on a continuous

basis.

15
i In order to analyze the quality of electrical service, the line voltage on the 208-volt side of the transformers will be recorded continuously.

It was decided to record the secondary rather than the primary voltage

because the secondary voltage is more responsive to load phenomena in the

building. The primary voltage depends more on what happens in the central

utility plant.

3.1.2 Water Metering '

The flew rates of chilled and hot water, and the return temperatures

and temperature differences, will be recorded at 5 minute intervals In each

building. Most water flow rates are to be measured by venturi meters using an electronic differential pressure cell as the flov transducer. Thenoocouples

are to be used to measure the actual temperatures of the hot and chilled

waters entering the building. Thermopiles will be uced to measura th«

temperature differences of the hot and chilled water entering and leaving

the building. The actual leaving temperatures will be calculated during

data analysis. (See Figure 6)

For large water flow rates venturi meters were selected because they

are sensitive to the anticipated minor variations in flow rates and they

have high efficiency and low pressure drop under these conditions. The

ASME standard venturi meters were selected rather than the short-form

venturi meters or orifice plates because of (jreater metering accuracv for flow

measurement.

The maximum Inaccuracy of each venturi meter in the design flow range

is specified as 0.25Z. Each venturi meter was individually calibrated

and has a calibration curve over the design flow range. In order to

obtain accurate pressure-drop data from the venturi flowmeters, electronic

differential pressure cells were selected. These cells have an error

16
of ± O.lOX or less. The differential pressure transducers generate a dc

voltage which is proportional to differential preasure.

Turbine flow meters will be used on pipe lines smaller than two

inches, and on the domestic hot water piping in the commercial, school,

and pre-school buildings. These meters will be protected by 5-micron

mesh strainers and have an error of O.IOZ or less. A pulse counter is to b

used to convert the turbine pulses to volume flow since each pulse corresponds to the passage of a known amount of water by calibration. The

-pulse counter signal is converted from digital to analog mode, providing

a dc voltage that is proportional to integrated count total. Turbine

flow meters were considered for the larger pipe sizes but were ruled out

because of high cost. However, turbine flow maters for the smaller pipe

sizes cost less than venturi meters fitted with the electronic differential

pressure cells.

3.1.3 Temperature Measurement

All temperatures are to be measured by calibrated coppar-constantan

thermocouples, using an electronic reference junction. The thermocouples

transmit a dc voltage which is proportional to the actual temperature.

Temperature differences are to be measured by multi-junction

differential thermopiles in order to obtain higher dc voltages for the small

temperature differences likely to occur. The dc voltage output is proportional to temperature difference. The temperature measurement system

will have the potential of measuring differential temperatures aa small

as 0.05 "F.

4. 2 Analog Recording

The analog strip chart recorder system will record all abnormal

performance in the total energy plant, including transient electrical
characteristics, engine malfunctions, operation of any of the safety

or protective devices on the system, and the time and duration of overloads on the electrical system.

As an example of its function, whenever the voltage on the main bus

^ drops ten percent below rated voltage, the electrical control system goes

Into a "system dump" sequence. This system-dump signal starts the analog

recorder. During the system-dump sequence, all electrical loads except

the essential loads are disconnected sequentially; that is, the normal

feeders to the buildings, the air conditioning system, street lighting,

10 etc., until the functioning generators are able to carry the reiulning

load. If the voltage keeps dropping, the total energy plant will be

shut down and the emergency public utility feeder for the essential loads

of the site will be energized. The total energy plant will remain shut

down until manually checked and restarted. If during system-dump sequence

15 the voltage stabilizes, all services will return automatically to normal

operation. The analog recorder will record the electrical transients

and generator phenomena during the overload period.

A. Special Data Collection Surveys

4.1 Air Pollution

20

The environmental effects of the total energy plant are part of the

field study. During the design stage, the National Bureau of Standards

studied existing and proposed regulations concerning emissions from

dlese 1-operated power plants, in order to comply with air pollution

regulations and to avoid neighborhood complaints.

25

18

)
10

15

20

For sulfur dioxide emission control, the State of New Jersey limits

the amount of sulfur allowed In the fuel to 0.27, by weight for No. 2

fuel oil and lighter olls.~^ For plant emissions, New Jersey has only a

2 / smoke requirement of No. 2 Rlngelmann on boiler stack emissions."

However, the New Jersey Air Pollution Control Administration has proposed

a "no visible smoke emission" requirement from boilers and diesels."^

Environmental Protection Agency (EPA) has no regulations covering this

plant, because of Its small size. The EPA air pollution regulations

cover all plants down to 250 x 10^ Btu/hr.^

y New Jersey Air Pollution Code, Chap. 10, Sulfur in Fuels, 5/1/68

0.27o sulfur effective 10/1/71.

2_l Ibid, Chap. 4, Smoke 1/1/58.

3/ Proposed Chapter 4, N. J. Air Pollution Code, 1/15/71.

4/ Federal Register, Vol. J6 , No. 159, August 17, 1971, p. 15706.

25

19
1/

The California truck dlesel-englne emission standards— for 1975 were

the only standards available for study of exhaust fwllutlon requirements

for dlesel prime movers. The limitations contained In these standards

Include the following:

1) hydrocarbons and oxides of nitrogen--5 grama per brake horsepower hour ;

2) carbon monoxide--25 grams per brake horsepower hour.

The California emission requirements made no reference to dlese 1-engine

driven stationary power plant8--only to dlesel engine-driven vehicles.

The specification prepared for the engine-generators to be Installed

In the Jersey City total energy plant cited the following maximum

values for exhaust emissions at a generator loading of 600 KW

:

1) unburned hydrocarbons -- 35 grama per hour;

2) carbon monoxide -- 700 grams per hour;

J) nitrous oxides 4500 grams per hour;

4) particulate matter 40 grams per hour;

5) smoke --No. 1 Rlngelmann maximum.

The emissions of each engine will be measured during pre-acceptance

factory testing, and again during the on-site acceptance tests.

y California Exhaust Emission Standards, Test and Approval Procedures

for Diesel Engine-driven vehicles In 1973, and subsequent Model

Year Vehicles, Over 6,001 Pounds Gross Vehicle Weight, 11/19/70.

5

20

25

20
In addition, total emissions from the total energy plant will be

measured. Exhaust emission sampling will be performed according to the

Environmental Protection Agency standards-^. Air samples at several

locations on and adjacent to the site will be measured at selected time

5 Inter/als. An air sampling survey of the site will be made before site

operation. This survey will be the base line for comparison with future

air-sampling surveys.

4 . 2 Noise Levels

Total energy plants can produce excessive noise outside the plant

10 building unless properly designed. At one total energy plant, the

National Bureau of Standards recorded sound pressure levels for infomiational purposes. It was found that the sound pressure level inside the

equipment room between two engine-generators was 104 dB (A). On the roof

of the same total energy plant about 30 feet from the cooling tower, the

15 sound pressure level was 68 dB (A).

The NBS performance specification for total energy plants required

that portable or permanent acoustic treatment be used to prevent exposure

2/ of working personnel to sound pressure levels In excess of 85 dB (A)— .

2 / In the control room the sound pressure level was limited to 70 dB (A)— .

20 After the Jersey City site is occupied and the total energy plant

is operating, a sound pressure level survey of the site will be conducted.

The results of this survey will be compared to the sound survey shown on

Fig. 7, made on that site by the National Bureau of Standards In September,

1970. This survey was conducted over a 72-hour period (Thursday,

25 y Federal Register, Vol. 36 No. 247, December 23, 1971, "Protection of the

Environment, Standards of Performance for New Stationary Sources".

2/ A Performance Specification for a Total Energy Plant at the Jersey City

BREAKTHROUGH I Site, P.R. Achenbach and J.B. Coble, NBS Report 10313

(Dec. 1970). 21
w a

'3Aviiwwns

5 QAia Aa3NN3)l
Friday and Saturday) and shows that the average sound pressure levels

ranged from 55 to 75 dB(A) during the survey period. The higher readings

were observed near the street where trucks and buses were the major noise

contributors. The total energy plant Is being Installed where the measured sound pressure level approximated 55 dB(A). The allowable increase

In sound pressure level over ambient sound pressure level due to operation

of the total energy plant was limited to 5 dB(A) in the performance

specification.

In order to comply with the specifications, extensive acoustical

treatment is being provided for the engine exhausts. The waste heat

recovery muffler Is designed to reduce the sound level by 13 decibels in

the frequency band of 4800/10,000 cycles per second. The exhaust muffler

on the stack is designed to reduce the exhaust noise by 26 decibels in the

frequency band of 37.5/75 cycles/sec and by 23 decibels in the frequency

band of 4800/10,000 cycles/sec. Acoustical treatment is also being

provided for the cooling towers which are mounted on the roof of the

central utility plant.

23
5. Summry of Field Studies

The planned field studies are comprised of the following major subdivisions: (a) an energy use study, (b) performance of the principal plant

components, (c) stability of the electrical service, (d) reliability of

the services, (e) environmental conditions at the total energy plant,

and (f) owning and operating costs.

Continuous measurement will be made for a year or more of the fuel

oil used, electrical energy generated, thermal energy utilized, excess

heat discarded, and the incremental use of electrical and thermal energy

by all major segments of the load.

Fuel oil consumption will be measured for all engines and '>Oth boilers,

and separately for each of two selected engines to provide a basis for

determining typical engine perforaance.

Electrical energy will be measured at all major points of utilization

Including (a) the amount distributed to the site, (b) the amount used by

each building, (c) that used by the commercial area, (d) that uaed by the

schools, (e) the amount used by plant auxiliaries, and (f) that used by

the central solid-waste collection system. The electrical energy generated by each of two of the engine-generators will be measured separately.

The data collection system will also permit determination of the energy

demand integrated over time periods of five minutes or any multiple

thereof up to daily and weekly patterns. Diversity factors of energy

use among the dwelling units in each apartment building can also be

determined.

5

5. 1 Energy Use Study
The thermal energy used in the absorption chillers, and in the

primary hot water heat exchangers in the plant and that discharged through

the water-to-air coolers (dry coolers) and through the engine-oil coolers

will be recorded at five minute intervals and integrated by computer

programs. Similarly the thermal energy used in each building for space

heating and cooling and for domestic water heating will be recorded at

five minute intervals and integrated.

5.2 Performance of Major Plant Components

The data collected on fuel use, electrical energy generation, thermal

energy produced, and thermal energy utilized will permit determlGatlon of

the thermal efficiency of the engine-generators, the heat recovery boilers

the absorption chillers, and the supplementary boilers. By analysis of

these data at various load levels performance curves can be produced for

all major types of mechanical equipment in the plant. Significant temperatures, pressures, speeds, and other operating parameters will be determined at the various load levels.

5.3 Stability of Electrical Service

Recordings will be made by the analog data system of transient conditions of voltage, frequency, power factor, and load division during

sudden load changes on the system, during load-dumping conditions when

overloads occur, and during the planned sequences of adding an enginegenerator to the distribution system or disconnecting one from service.

These data will not be collected continuously, but on a planned basis

when the phenomena permit, or during short periods of eaergency whenever

these occur.

25
5.4 RP-Habllltv of Services

Detailed records will be made of Che duration and characteristic

parameters of Interruptions to the electrical service and heating and

cooling services caused by overload or malfunction of equipment. The

functioning of all of the alarms and protective devices on the enginechillers, boilers, and chillers will be monitored. These operating

data, together with documented maintenance and repair operations^ vd.ll

constitute a record of reliability of the principal aechanical and electric

components of the plant.

5 . 5 Environmental Conditions at the Total Energy Plant

In addition to the air pollution and noite aurveys described earlier

in this report^ noise and vibration measureaenta will also be made of each

engine-generator after installatioo for comparison with similar data

taken during factory tests and aa a basis for estimating appropriate overhaul periods for the engines. Lubricating oil contaminant levels will also

be monitored as a possible indicator of engine condition.

Illumination levels, thermal environment, and ventilation around

major pieces of plant equipment and controls will be observed and compared with specification requirewnts

.

5.6 Ovming and Operating Costs

A complete record of o%mlng and operating costs for the total energy

plant will be kept including investment cost, financing costs and fees,

fuel costs, costs for scheduled maintenance and overhaul, and for breakdown maintenance, costs for repair parts and inventory, plant operation

and management, taxes, depreciation, insurance, and water; and credits for

energy supplied to other facilities and for decreases in costs for other

26
services such as solld-vaste management. Records of maintenance, repair,

and overhaul coats will be kept for a perlo<l of three to five years to

properly evaluate the effect of the minor and major overhaul of engines

on total costs.

The results from the Jersey City study are expected to constitute

a good technical and economic base for evaluating the potential for

wider application of total energy plants. This study and parallel market

studies should provide sufficient data to consider whether total energy

plants could be beneficially combined with waste treatment facilities or used

as satellite systems Interconnected with urban energy systems.

USCOMM4<U-OC

27

NBS-lUA (REV. 7-73)

U.S. DEPT. OF COMM. 1 ). PUHI.K ATION OR RI-PORT NO.

BIBLIOGRAPHIC DATA | SHEET WR.q TP- 7^^-711

2. Gov 't Ac< < ss ion No.

4. TITLE AND SUBTITLE

Site Analysis and Field Instrumentation for an Apartment

Application of a Total Energy Plant

5. Publication Date May 19, 1975

6. Performing Organization ( ode

7. AUTHOR(S)

John B. Coble and Paul R. Achenbach

8. Pcrlorming Organ. Report No.

9. PERFORMING ORGANIZATION NAME AND ADDRES.S

NATIONAL BUREAU OF STANDARDS

DEPARTMENT OF COMMERCE

WASHINGTON, D.C. 20234

10. Proiect/Task/Work Unit No. I1628I422

11« (-ontfiict/Cjr iin t No.

12. Sponsoring Organization Name anj C ompleic Addrrss (Street, City, State, ZIP)

U, S. Department of Housing and Urban Development

451 7th Street, N.W.

Washington, D.C. 20410

13, Type of Hfport & J^er i od Covered

Jjina-L

14. .Sponsoring Agency ( ode

15. SUPPLEMENTARY NOTES IR combines two talks given by J.B.Coble and

P.R, Achenbach at the 7th Intersociety Energy Conversion Engineering Conference at

San Diego, California, September 25-29, 1972,

I 16. ABSTRACT (A 200-word or less (actual summary ot most Kigpilicant information. If document includes a significant

I bibliography or literature survey mention it here.)

Under sponsorship of the Department of Housing and Urban Development, the National

' Bureau of Standards developed criteria in a feasibility study to select a site for,

and to evaluate the requirements of a total energy system on one or more OPERATION

BREAKTHROUGH housing sites. The total energy system produces its own electrical,

heating and cooling energy services independent of the local utility system. Six

OPERATION BREAKTHROUGH sites were selected for the feasibility study: Jersey City,N.J.;

Macon, Ga. ; Memphis, Tenn. ; Indianapolis, Ind, ; St, Louis, Mo.; and Sacramento, Calif.

Ranking parameters for final selection were: number of dwelling units, density of

dwelling units, climatic factors, energy utilization, owning and operating costs, and

I developer's attitude.

The Jersey City site was chosen as the location for the installation, evaluation, and

field study of the total energy system. The site covers six acres, has four apartment

I buildings containing 488 dwelling units, a 50,000-sq.ft commercial building, an ele-

! mentary school, a swimming pool, and the total energy plant.

Hie buildings and the total energy plant are being extensively instrumented to provide

data on fuel utilization, system efficiencies, electrical and thermal energy generaI tion, energy utilized and rejected. The environmental impact of the total energy

I plant with respect to noise, vibration, air pollution, and esthetics is under evalu-

! ation. The installed system will be compared with several types of conventional

I- 17. KEY WORDS (six to twelve entries; alphabetical order; capitalize only tf»e first tetter of the first key word unless a proper name; separated by semicolons) Air conditioning; air pollution; Central Utility systems;

data acquisition system; efficiencies; electrical power; energy conservation; energy

costs; fuel utilization; h6*t recovery; total energy systems; utilities for housing;

utility system performance.

18. AVAILABILITY f^Jnlimitcd 19. SECURITY CLASS

(THIS REPORT)

21. NO. OF PAGES

1

' For Official Distribution. Do Not Release to NTIS

UNCLASSIFIED

63

!!

1

1 Order From Sup. of Doc, U.S. Government Printing Office Washineton. D.C. 20402. SD Cat. No. CH

20. SEC URITY ( LAS.S

(1 MIS PACE)

22. Price

1 XI Order From National Technical Information Service (N l IS) Springfield, Virginia 22151 UNf LASSn iED $4.25

USCOMM-DC 29042-P74