3? NBS

Pubii - cations

A111D4 4 T fl 3 5 2

NBSIR 78-1563

Guidelines for Evaluation of a

MIUS Demonstration

Richard A. Grot

David J. Mitchell

John R. Schaefgen

Allen C. Chao

Mark E. Kuklewicz

Stephen F. Weber

Center for Building Technology

National Engineering Laboratory

National Bureau of Standards

U.S. Department of Commerce

Washington, D C. 20234

December 1978

Prepared for Division of Energy, Building Technology and Standards

Office of Policy Development and Research

Department of Housing and Urban Development

Washington, D.C. 20410

. U56

7/8-1563

1 QC

‘ 100

MODULAR INTEGRATED

mius UTILITY SYSTEMS

improving community utility services by supplying

electricity, heating, cooling, and water/ processing

liquid and solid wastes/ conserving energy and

natural resources/ minimizing environmental impact

WmaQmM o? Standards MAY 1 4 1379

NBSIR 78-1563

i s\

GUIDELINES FOR EVALUATION OF A

MSUS DEMONSTRATION

r

Richard A. Grot

David J. Mitcheli

John R. Schaefgen

Allen C. Chao

Mark E. Kuklewicz

Stephen F. Weber

Center for Building Technology

National Engineering Laboratory

National Bureau of Standards

Washington, D.C. 20234

December 1978

Prepared for Division of Energy, Building Technology and Standards

Office of Policy Development and Research

Department of Housing and Urban Development

Washington, D.C. 20410

mm

•«'**«« 0«

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

Dr. Sidney Harman, Under Secretary

Jordan J. Baruch. Assistant Secretary for Science and Technology

NATIONAL BUREAU OF STANDARDS, Ernest Ambler, Director

FOREWORD

The development of communities is often restricted by the lack of

adequate utility services to handle the requirements of additional

population, industry, institutions and commercial establishments.

The nation's fossil fuel reserves, particularly petroleum and natural

gas, are diminishing. New connections to natural gas distribution

systems are unavailable in many parts of the country. The capacity

of many electric utility companies is being pushed to the limit, and

addition of new generating facilities is both expensive and slow. The

use of coal, the nation's most abundant fuel, is constrained by air

pollution regulations, potentially inadequate coal transportation systems and declining productivity in underground coal mining. The growth

of nuclear generating facilities is behind schedule due to environmental

problems, financing difficulties, uncertainty in future load demands,

and questions of safety.

Most urban areas have serious problems related to the adequate treatment

and disposal of wastewater and solid waste. The deterioration of the

quality of our natural bodies of water has imposed requirements for

upgraded wastewater treatment systems in most urban areas. The capital

investment required to upgrade existing facilities has added to the

solvency problems of local governments. In order to prevent increases

in existing pollution levels, until facilities can be expanded or upgraded, moratoria have been imposed on new connections to the sewer

system. Restrictions on incineration due to air pollutant emissions

from incinerators have forced most municipalities to depend on costly

transportation of sludge and solid wastes to increasingly remote landfill sites.

The solutions to these problems are implemented on two extremes of

scale: either regionally with large complex facilities, or individually

at each residence or building. Each utility service is provided separately, even though the inability to solve problems with any one service restricts

the orderly development of communities.

The Department of Housing and Urban Development's (HUD's) Office of Policy

Development and Research had been working to reduce the cost of utility

services, thereby lessening a major constraint on production and marketability of housing. This effort was directed increasing attention

at the consumer side of the energy problem, especially as it relates

to residential energy consumption. HUD's research efforts were directed

at more efficient utilization of energy rather than increased production

of energy. Overall efficient use of energy in housing and associated

facilities is important. The residential and associated commercial

sectors account for one-third of the total energy consumed in the United

States. Thus, significant energy resources savings and environmental

improvements can be affected by improved energy utilization within these

sectors. As a part of its work in energy research for community development,

HUD embarked upon an important research effort, the development of a Modular Integrated Utility System (MIUS)

iii
The concept of a Modular Integrated Utility System is to combine the

five basic community utilities: electrical service, thermal services,

wastewater treatment, solid waste management and water purification,

into one system. The overall objectives of the MIUS concept are

to :

° Provide utility services in an improved manner with advantages in

lower total cost, decreased environmental impact, and increased

efficiency in the utilization of natural resources;

0 Provide utility service capacity at a pace equal to the rate of

growth of the new development; and

° Make land available for development in areas that are not being

serviced by conventional utilities.

Conceptually, significant energy resources savings and environmental

improvements can be affected. MIUS can recover and recycle energy

that would normally be wasted by larger-scale conventional utility

systems. Conventional methods of generating electricity waste

about 65% of the energy input in the form of excess heat. MIUS

has the potential of recovering over half of this excess heat and

of using it for space heating, space cooling and potable water.

An additional 5-10% fuel savings can be achieved by recycling solid

waste for its energy content. Recovered excess heat can be utilized

to stabilize the wastewater treatment processes. The effluent from

the wastewater treatment process can be utilized for non-potable

uses such as irrigation, condenser cooling, thermal energy conveyance

or for other non-potable MIUS plant purposes. Incineration of solid

waste reduces the landfill requirement of the community, and can significantly alter the character of the solid waste, since the disposed

material is a sterile ash instead of putrescible solids.

The HUD MIUS Program was a multi-agency undertaking which has included the

Department of Commerce through the National Bureau of Standards (NBS);

the Energy Research and Development Administration through the Oak

Ridge National Laboratory, the Office of Conservation, and the Office

of Fossil Energy; the National Aeronautics and Space Administration

through the Johnson Space-flight Center; the National. Academy of

Engineering; the Environmental Protection Agency through the Municipal

Environmental Research Laboratory; the Department of Health, Education

and Welfare; the Department of Defense; the Federal Energy Administration;

the Federal Power Commission; the Veterans Administration; and three

representatives of the private sector — the International District

Heating Association, the Edison Electric Institute and the American

Public Power Association. Inclusion of the last three listed organizations

as participants is one indication of industrial interest in MIUS.

The dependence of the MIUS concept on district heating and cooling

systems made IDHA participation a valuable asset. The EEI formed

a Task Force on Co-Generation to comment on MIUS analyses and data

and to explore industry attitudes toward the MIUS concept.

IV
The National Bureau of Standards' prime responsibility had been in the

experimental design, data collection, and evaluation of ongoing and

planned HUD MIUS demonstration projects. Planning for the evaluation

of a MIUS demonstration is the subject of this report. Although such

a demonstration did not occur, the issues identified and the strategy

developed to address

the field evaluation

them should be of interest to those envolved in

of integrated energy systems.

ACKNOWLEDGEMENT

The authors wish to acknowledge the invaluable technical assistance

of Donna L. Brown in editing several portions of this report.

v
TABLE OF CONTENTS

Page

List of Figures and Tables V-Lj_

Units of Measure and S.I. Conversion Factors viii

Abstract 1

1. INTRODUCTION 1

1.1 Demonstration of MIUS Technical Performance 2 1.2 Demonstration of MIUS Public Benefits 2 1.3 Demonstration of the Viability of Private Sector

Ownership and Operation of a MIUS 2 1.4 Establishment of a Data Base for the Further MIUS

Implementation 3 1.5 Scope of the MIUS Evaluation Guidelines 3

2. DESCRIPTION OF THE MIUS DEMONSTRATION SITE 4

3. MIUS TECHNICAL EVALUATION PLAN GUIDELINES 7

3.1 MIUS 7 3.2 Electrical Service Subsystem 9

3.3 Thermal Subsystem 12

3.4 Solid Waste Management Subsystem 18

3.5 Wastewater Management Subsystem 25

3.6 Building Loads 28

4. THE FINANCIAL/ECONOMIC EVALUATION PLAN 31

4.1 Real Estate Developer Viewpoint 31

4.2 Electric Utility Viewpoint 33

4.3 State and Local Government Viewpoint 33

4.4 Federal Government Viewpoint 34

4.5 Other Institutions Viewpoints 34

4.6 Data Collection 34

5. CONCLUSIONS 36

6. REFERENCES 37

Vi
LIST OF FIGURES AND TABLES

Page

Figure 2.1 St. Charles MIUS Site Plan 5

Figure 3.1.1 MIUS Functional Diagram 8

Figure 3.2.1 Electical Service Subsystem Functional Diagram . . 10

Figure 3.3.1 Thermal Subsystem Functional Diagram 13

Figure 3.4.1 Solid Waste Subsystem Functional Diagram 19

Figure 3.5.1 Wastewater Management Subsystem Functional

Diagram 26

Figure 3.6.1 Site Utility Load Data Acquisition Scheme 30

Table 2.1 MIUS Demonstration Site Buildings Description . . 6

vii
UNITS OF MEASURE AND S.I. CONVERSION FACTORS

In NBS Document LC 1056, revised August 1975, guidelines were established

to reaffirm and strengthen the commitment of NBS to the greatest practicable

use of the International System of Units (S.I.) in all of its publications

and also in all of its dealings with the science and engineering communities

and with the public. In this report the measurements are those of the U.S.

Customary units as they appear in the referenced standards, in order that

the readers may give full attention to the organization and compilation of

the criteria.

The following conversion factors are appropriate for the units of measure

that appear in this report:

Area

o

1 acre = 4046.873 square meter (m )

1 square foot ( f t

^ ) = .09290304 square meter (m )

Energy

1 British Thermal Unit (Btu)= 1055.056 Joule (J)

1 kilowatt-hour (kWh) = 3600000.0 Joule (J)

1 ton-hour = 12660672.0 Joule (J)

Flow Rate

1 U.S. gallon per minute (gpm) = 0.0000630902 meters'5 / second

= 63.0902 centimeters'Vsecond (cm /s)

= 0.0630902 liter s/ second (L/ s)

Length

1 inch (in.)

1 foot (ft.)

1 mile

0.0254 meter (m)

0.3048 meter (m)

1609.347 meter (m)

Mass

1 pound-mass (lbm) .4535924 kilogram

Temperature

1 Degree Fahrenheit (°F) = (1.8)

-

^ kelvin (K) or (°K)

Temperature Fahrenheit (°F) = (459.67 + temp. °F)/1.8 ( °K)

Time

1 hour (h) = 60 minutes (min) = 3600 seconds ( s)

Volume

1 U.S. liquid gallon (gal) = 0.003785412 meter^ (m^

)

= 3.785412 liters (L)

viii
GUIDELINES FOR EVALUATION

OF A MIUS DEMONSTRATION

Richard A. Grot

David J. Mitchell

John R. Schaefgen

Allen C. Chao

Mark E, Kuklewicz

Stephen K. Weber

Abs tract

In order to obtain maximum benefits from a demonstration of a Modular

Integrated Utility System (MIUS), a carefully-planned evaluation should:

assess the technical performance; determine the public benefits; show

the viability of private ownership; and provide a data base to support

future analyses of MIUS. This document is a guideline for the development

of a detailed evaluation plan for a MIUS facility which was planned

for demonstration at St. Charles, Maryland. Generic types of technical,

institutional and economic issues are discussed. General performance

measures for the total system and each subsystem are indentified. The

classes of data required and the types of data analyses that should

be employed are outlined.

Keywords: Co-generation; integrated utility systems; solid waste

management; thermal systems; total energy; wastewater

treatment

1. INTRODUCTION

The integration of the normally separate utility services which a community requires into an integrated utility system and the development of that system on a modular basis in step with the development of

the community are conceptually attractive. However, the nature of the

process under which a community is established and the lack of experience and expertise which a conventional developer has at his disposal

led the Department of Housing and Urban Development (HUD) to undertake

a demonstration project to investigate how a Modular Integrated Utility

System (MIUS) would be designed, constructed and evaluated as a part

of the total development of the community [ 1 ] ^

. The principal objectives

of the MIUS demonstration were:

° To demonstrate the technical performance of a MIUS,

To demonstrate the public benefits of a MIUS,

° To demonstrate the viability of private sector ownership

and operation of a MIUS, and

To establish a data base to further implementation of MIUS.

1 See reference 1 at end of text.

1
1.1

DEMONSTRATION OF THE TECHNICAL PERFORMANCE OF A MIUS

A Modular Integrated Utility System can provide community utility services

using less resources. However, there are a series of technical issues

to be addressed and answered by the MIUS demonstration. The quality

of service should be established, and compared with applicable laws and

regulations, conventional practices, the contractual performance specifications, and the aspirations of the MIUS users. Reliability of the

MIUS plant and utility service should be determined in comparison to

conventional utility services. Practicality of the MIUS Performance

Guidelines [14] must be determined. The contractual performance specifications represent what appears to be a realistic and economic level

of attainment, based on numerous analytical systems studies and technology

evaluations. Technical and cost information from the evaluation will

be necessary to assess the practicality of the guidelines and revise

them where necessary. The relation between MIUS characteristics and

technical performance should be determined. There should be a determination

of the effects of integration of several separate utility subsystems

on maintenance, reliability, and efficiency. There should also be a determination of the effects of size and complexity on maintenance

and efficiency.

1.2 DEMONSTRATION OF MIUS PUBLIC BENEFITS

An assessment of the public benefits of a MIUS entails determining:

° The reduction in environmental degradation due to MIUS deployment;

° The efficiency with which MIUS utilizes natural resources;

° The reduction in total costs to the community for MIUS - provided utility services;

° The reduction in use of fossil fuels due to a MIUS;

0 The reaction of a community to a MIUS and its services; and

° The consistency of a MIUS approach with other governmental

regulations and policies.

1.3 DEMONSTRATION OF THE VIABILITY OF PRIVATE SECTOR OWNERSHIP AND

OPERATION OF A MIUS

Efforts to promote implementation of the MIUS concept require that

the MIUS demonstration provide information on the following topics:

° Profitability of ownership and operation;

° Risk of ownership and operation;

° The phasing of MIUS capacity to community growth;

0 Clarification of institutional and legal barriers which

inhibit developer implementation;

0 The effect of merging services on productivity and cost savings; and

° The response of a design professional to a performance specification.

2
1.4 ESTABLISHMENT OF A DATA BASE FOR FURTHER MIUS IMPLEMENTATION

Successful implementation of MIUS at a minimum cost requires design

improvements which cannot be accomplished with existing data. Economic,

technical, institutional and plant design data is insufficient for sound

private investment. The accuracy of preliminary estimates of MIUS

benefits and markets should be established. The necessary institutional

scenarios for MIUS should be specified. Technological improvements which

optimize MIUS cost effectiveness should be identified in order to obtain

private sector follow-on. Legislation to remedy institutional disincentives

to MIUS should be identified and described. Data identifying effects

of integration on MIUS performance and efficiency should be collected.

1.5 SCOPE OF THE MIUS EVALUATION GUIDELINES

The following sections of this document provide guidelines for

developing an evaluation plan for a MIUS in St. Charles, Maryland.

This evaluation plan should address the technical, economic and environmental issues necessary for a successful implementation of the MIUS

concept. An evaluation conducted according to these guidelines should

provide answers to the important issues noted above and supply knowledge

necessary to minimize impediments to the future application of MIUS.

The implementation of the guidelines to produce a final evaluation plan

for determining the performance of the MIUS demonstration project should

entail:

° Development of specific performance factors for both the total

MIUS and the individual subsystems;

° Specification of the data requirements (e.g. location, accuracy,

frequency)

° Identification of critical system components and their impact

on system performance;

° Development of analysis schemes and models for evaluating

benefits from a MIUS; and

° Identification of alternative utility systems for comparison

with MIUS.

It is important that the evaluation plan be not only technically correct

but also that it provide information that will be practical for the

individuals and institutions which will be involved in the implementation

of the MIUS concept. Therefore the evalution plan should be developed in

close conjunction with individuals, groups, institutions and governmental

agencies who will eventually be involved in the future implementation

of the MIUS concept.

3
2 . DESCRIPTION OF MIUS DEMONSTRATION SITE: ST. CHARLES, MARYLAND

The Department of Housing and Urban Development awarded a grant to

Interstate Land Development, Inc. (ILD), the developer of St. Charles,

Maryland, to develop the design of a MIUS which can provide utility

services within a limited service area at St. Charles. St. Charles,

a HUD New Community, is located approximately 25 miles south of

Washington, D.C. The entire HUD New Community consists of approximately

8,000 acres, including residential, commercial and industrial elements.

The MIUS site was to constitute 130 acres of St. Charles (Figure 2.1)[2]^,

to be occupied by a mix of residential, commercial and institutional

buildings. The MIUS was to provide electrical service (partial), space

heating, space cooling, domestic hot water service, solid waste disposal

and treatment, and wastewater management for the MIUS site. Due to

institutional constraints, some (if not all) of the customer buildings

would have received electricity from Southern Maryland Electric Cooperative

(SMECO), the remainder being provided electricity directly by the MIUS.

A portion of the electricity furnished by SMECO was to be generated

by the MIUS as a byproduct of satisfying thermal heating demands of

the site, or during SMECO system peaking periods when the MIUS was

to operate at maximum available electrical output. The remainder of

the electrical energy consumed on the site was to be purchased from

another utility, since SMECO is a non-generating cooperative. The projected

loads for the utilities’ services are presented in Table 2.1 (adapted

from reference 2).

2 Figure 2.1, is taken from reference 2. Reference 2 contains a detailed

description of the total MIUS site and preliminary plant design.

4
5
WASTEWATER

ESTIMATE

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ANNUAL

ENERGY

CONSUMPTION

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be

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units
3. MIUS TECHNICAL EVALUATION PLAN GUIDELINES

The MIUS technical evaluation should consist of six parts: a system

evaluation of MIUS; an evaluation of the electrical service, thermal,

solid waste management, and wastewater treatment subsystems; and an evaluation of the individual building loads.

3.1 MIUS

3.1.1 System Definition

The total MIUS plant was to consist of a group of four major subsystems: an electrical service subsystem, a thermal subsystem, a solid waste management subsystem and a wastewater treatment subsystem.

The integration of these typically separate functions into an integrated utility system was accomplished with the goal of providing the

accustomed utility services quality at a reduced cost (Figure 3.1.1).

3.1.2 Technical Issues to be Addressed by the Evaluation Plan

The total system performance should be determined by evaluating the actual

performance of a MIUS plant in comparison to a series of other utility

configurations which could have been implemented at St. Charles and

by determining the marginal utility of integrating the utility subsystems

into one system. The major categories of this evaluation should consist

of :

° The effectiveness of a MIUS plant in reducing the consumption

of natural resources;

° The operational reliability of a MIUS plant;

0 The maintenance requirements of a MIUS plant; and

0 The nature of the emissions from a MIUS plant.

3.1.3 System Data Requirements

The parameters which should be measured for a total-system evaluation of the MIUS plant are those related to the major MIUS energy and mass flows (see Figure 3.1.1). One should measure:

1) the fuel consumed by the total MIUS, by the engine-generators,

by the boilers and by the solid waste management subsystem;

2) the total electricity produced, the electricity delivered to

the site, the electricity used by the major subsystems and the

electricity used by centrifugal chillers;

3) the total heat produced, the heat delivered to the site by

type, the heat recovered from the major subsystems, and the

heat delivered to the absorption chillers;

4) the total quantity of cooling produced, the heat removed from

the site, and the cooling produced by each type of refrigeration

equipment;

7
€>3

Cou

Figure

3.1.1

MIUS

FUNCTIONAL

DIAGRAM
5) quantity of the solid waste incinerated and quantity of ash

disposed

6) quantity and quality of raw sewage;

7) quality and quantity of the treated effluent; and

8) the emissions from the MIUS plant.

3.2 ELECTRICAL SERVICE SUBSYSTEM

3.2.1 Subsystem Definition

The function of the electrical service subsystem was to provide

electrical energy for use by the MIUS site users and by other MIUS

subsystems. The electrical service subsystem was also a source of heat

energy which potentially can be recovered and utilized by other MIUS

subsystems and by the MIUS site (see Figure 3.2.1). The electricity

generated by the electrical service subsystem was to be utilized in

three ways: 1) by other MIUS subsystems in performing their prescribed

functions, 2) by the MIUS site users directly, and 3) by MIUS site users

or users exterior to the MIUS site indirectly through the local utility

(SMECO). In the event of a failure of the local utility system, the

MIUS electrical subsystem would have been able to satisfy most electrical

needs of the MIUS site directly.

3.2.2 Technical Issues to be Addressed by the Evaluation Plan

A technical evaluation plan for the electrical service subsystem

should provide a methodology for determining

° The operational efficiency of the electrical service subsystem;

° The quality of the electrical service;

The quality of the recoverable heat from the subsystem;

The reliability of operation of the electrical subsystem; and

° The emissions from the diesel engines.

Operational Efficiency

There are potentially three operating efficiencies of importance to

the evaluation of the electrical service subsystem: the electrical generating efficiency, the total operational efficiency and the potential

operating efficiency. The electrical generating efficiency is a measure

of the ability of the subsystem to convert fossil fuel energy into electricity and is defined as the ratio of the energy content of the electricity generated by the subsystem divided by the energy content of the fuel

consumed. The electrical generating efficiency is a subsystem peformance

measure that permits a direct comparison of the subsystem's performance

in producing electricity with the efficiency of a conventional generating

facility (which has electricity as its only product). The total operational efficiency of the electrical service subsystem can be defined as

a ratio of the total useful energy generated by the subsystem divided

by the energy content of the fuel consumed. The total useful energy

9
Electricity

Delivered

to

Site

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generated is the sum of the energy content of the electricity generated

and the thermal energy recovered from the subsystem. The total operational

efficiency is a true measure of the effectiveness of the subsystem

in utilizing fuel resources. Whereas it is expected that the electrical

generating efficiency will be lower than that of a large-scale generating

facility, the recovery and useful application of the normally rejected

thermal energy should result in an operating efficiency significantly

greater than that of a conventional facility. The potential operating

efficiency is defined as the ratio of the potential delivered energy

to the energy content of the fuel consumed. The potential delivered

energy is the sum of the recoverable energy (energy available for use by the thermal subsystem) and the electrical energy generated. The

potential operational efficiency is a measure of the maximum obtainable

performance of the subsystem in its present design configuration. It is a useful criterion for evaluating potential design improvements and

modifications to operational procedures.

The Quality of Service

The quality of electrical service is a measure of the electrical service

subsystem's ability to provide electrical power which will permit user's

equipment to function properly and without risk of damage. The specific

performance measures of quality of electrical services are: the ability

of the electrical generating equipment to meet the users' load, line

voltage stability, the frequency stability of the A-C signal, and the

nature and duration electrical transients. Any inability of a MIUS

plant to meet user load requirements without reducing voltage could

cause damage to users' equipment. Similarly, excessive variations in

line voltage are unacceptable. Frequency stability is important for

proper functioning of clocks and many electronic devices. Spikes or transients can seriously damage modern electronic equipment that MIUS

users may be operating. Future acceptance of MIUS installations will

depend on the confidence of potential users in the ability of a MIUS

to provide an electrical service of the quality required by their

applications .

Thermal Quality of the Recoverable Heat

The temperature and pressure of heating energy required by the site users largely dictate the selection of the MIUS prime mover. Several

quality levels of heat may be available from the prime mover for different

applications. High grade heat with a temperature in excess of 200°F has

many applications. Low grade thermal energy in the temperature region

of 140 to 180°F can be used in some instances for heating domestic hot

water, space heating or as preheat.

Reliability of Operation

Maintenance requirements and downtime of the subystem are important

measures for determining the economic viability of the future MIUS

installation. Uncertainity in reliability tends to lead to an over-design

11
of the subsystem. This could make the MIUS economically less attractive.

Furthermore the reliability of the installation is of prime concern

to potential MIUS users.

Emissions from the Diesel Engines

The Ambient Air Quality Standards for the State of Maryland regulate the amount of sulfur oxides, particulate matter, carbon monoxide,

non-methane hydrocarbon, photo-chemical oxidants and nitrogen dioxide

resulting from power plant combustion. It will be necessary to obtain

data on the amounts of these pollutants which the electrical subsystem's

prime movers are emitting to the environment. In addition, the amount

and nature of noise pollution generated by the engine generators should

be measured as a part of the environmental impact evaluation.

3.2.3 Subsystem Data Requirements

Subsystem data requirements for the evaluation of the performance of

the electrical subsystem should include: fuel consumed, electrical

energy generated, recovered thermal energy, recoverable thermal energy,

subsystem down-time, subsystem maintenance requirements, line voltage

(over time), line frequency (over time), the temperature of the available

thermal energy, the concentrations of the major emissions in the

surrounding community, and the magnitude and frequency of the plant

noise

3.3 THERMAL SUBSYSTEM

3.3.1 Subsystem Definition

The thermal subsystem (TS) of a MIUS facility was to consist of the

assembly of equipment that generates and distributes heating and

cooling services to the site, and serves to transfer thermal energy

between other subsystems within a plant. The basic energy transfers

are shown in Figure 3.3.1. The thermal subsystem component equipment

consists of boilers, chillers, heat exchangers, heat rejection equipment

(cooling towers), fuel supply, thermal storage devices and thermal service

distribution throughout the site.

3.3.2 Technical Issues to be Addressed by the Evaluation Plan

The evaluation of the thermal subsystem should provide technical

and cost information to analyze the energy savings resulting from

several heat recovery techniques. Performance information should

include energy efficiency, utilization effectiveness, and operational

information necessary for cost and reliability studies. The major

areas of evaluation are:

12
Exhaust

Gas

vs>

.E

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COc

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13

Figure

3.3.1

THERMAL

SUBSYSTEM

FUNCTIONAL

DIAGRAM
Heat Recovery

° Reliability and service requirements of heat recovery equipment,

° Reduction of thermal pollution of surface water and ambient air,

° Effectiveness of heat recovery techniques in actual demonstration,

and

° Degradation of thermal transfer surfaces;

Cooling Production

° Thermal energy requirements of the site,

° Subsystem heating loads,

° Heat produced by solid waste incineration and its usefulness,

0 Reliability and performance of thermal heat production equipment,

° Heat required by the wastewater treatment system and heat made

available to it , and

° Fuel savings due to MIIJS supplying the site;

Cooling Production

0 Energy required to provide cooling to site,

0 Energy required to provide cooling to MIUS subsystems, and

° Reliability, load factors and equipment efficiencies;

Heat Rejection

° MIUS heat rejection, equipment load factors and use patterns, and

° For each thermal equipment group determine the cause and percent

of input energy rejection during operation;

Thermal Storage

0 Potential for reduced capacity of thermal subsystem equipment

by use of thermal storage techniques,

° Technical performance of thermal storage integrated with other

subsystems

,

° Comparison of actual performance against equipment specifications

and subsystem design criteria, and

° Potential for saving of fuel resources by use of thermal storage

in integrated systems; and

Service Distribution

0 Load patterns for different users and site buildings (for

comparison with design values and to demonstrate potential

for controlled subsystem and user peak loads), and

° Performance (load factors, maintenance requirement,

reliability and cost).

14
3.3.3 Subsystem Data Requirements

Energy Flows

The evaluation of the thermal subsystem should have information con- cerning the supply (and removal) of thermal energy to (or from) the site.

The evaluation of the subsystem's ability to meet the design thermal load

limits should be undertaken. Seasonal (typical day) and peak consumption

and production values should be reported. Values from adjusted loads on individual equipment or separate tests should also be used to verify specified capacities.

Summaries of heat and chilled water production using weekly sum- maries correlated with season, weather and site characteristics should

be reported. Some characteristic hourly plots during the heating, cooling,

Spring and Fall seasons should be included.

The measured peak, seasonal average, daily, and monthly heating

and cooling loads should be charted, along with site characteristics

and weather parameters. Prime-mover recovered-heat charts should be

assembled from measured data. The flow rates and pumping power of

major TS loops (and the TS net electrical load) should be measured.

Thermal energy distribution losses and thermal energy storage effectiveness should be measured by special tests. Measurement of the energy

transfer parameters at the point of delivery to site building groups

should be accomplished and the average thermal load in one-hour intervals for four two-week periods of the year should be reported. These

periods should correspond to the annual heating, cooling, Spring and

Fall seasons. Service distribution results should provide quantitative

data on the quantity of thermal energy lost between the MIUS plant

and the user building interfaces.

Service Quality

Verification of thermal subsystem performance with respect to the

design limits specified in the performance specification should be

accomplished. This will require monitoring of pressure, flow and

temperatures, as appropriate, for each type of plant thermal service

and/or heat exchanger. The percentage of time that the MIUS TS plant/

distribution system performs within the design limits should be calculated

based on this information. Service quality at the consumer end of the TS

distribution system should also be summarized based on information from

pressure, flow and temperature measurements.

Subsystem Energy Efficiency and Effectiveness

The utilization of supplied and recovered thermal energy to/from other

subsystems should be analyzed. The information should be used to

determine if the inter-subsystem thermal transfers actually improve the

thermal efficiencies, energy effectiveness and financial performance

of the MIUS. Emphasis should be given to determining the appropriate

measure of utilization of recovered energy.

15
TS Subsystem Integration

Thermal subsystem interfaces occur with all of the other MIUS subsystems.

The minimum interface would be TS heating and cooling service to the

MIUS personnel and the enclosed building space. Any study of TS integration

should include the documentation of input (recovered) and output (consumed)

energy

The principal integration with the electrical service subsystem (ESS) occurs where recovered usable prime-mover thermal energy is transferred.

A study of the ESS and TS integration should determine the net energy

flows and includes TS cost and energy utilization information. It should

address whether the ESS and TS integration results in either fuel or dollar

savings over conventional alternates.

TS integration with the solid waste management subsystem and the wastewater

management subsystem (WMS) should be documented in the same way as

the TS-ESS integration. Utilization 6 f the recovered heat should not

be credited to more than one subsystem source, and should be considered

separately from thermal energy generated by TS boilers using fossil fuels.

Much of the thermal energy information needed for evaluation of integration concepts is also required for studies of energy efficiency, energy

effectiveness, and energy conserved. Extensive instrumentation will be

required to monitor the actual MIUS TS energy transfers. Information

collected to review the service quality and quantity criteria will also

be useful in the integration study. As an example, the MIUS specifications limit the thermal energy rejection to the WMS by limiting effluent

temperatures to 5°F above the temperature of the receiving body of

water. Thermal subsystem fluids drained to the WMS should also be

considered

Component Energy Efficiency and Effectiveness

Energy efficiency ratings of individual equipment and component groups

should be generated at varying intervals depending upon the specific

equipment characteristics in a final MIUS plant design. These data

should be reported on a monthly basis for equipment such as boilers

and heat exchangers in order to establish any degradation of the heat

transfer surfaces. Cooling towers, some chillers, and heat pumps that

have variable efficiencies with time or weather conditions will require

more frequent monitoring of operating efficiency.

Energy Conserved

Determination of the energy conserved by the as-built MIUS plant should

be a major goal of the evaluation. Row well each TS component group

transfers or changes the form of energy which it is dealing with has

a significant impact. The selected equipment in each of the component

groups of heat recovery, heat production, cooling production, heat rejection,

thermal storage and service distribution affects the final plant energy

consumption rate. The major elements of thermal and electrical production,

as well as fuel consumption, should be measured to determine the actual

TS plant performance.

16
The energy conservation comparison can be approached from different

bases. One comparison should be against two or three alternate total

energy and MIUS plant designs. Alternates would include different

prime movers, subsystem interfaces, cooling equipment, and variations

in operating schedules and philosophy. Another comparison should be

the performance of the conventional utilities with which ILD had planned

to market the buildings on the site. With the exception of two buildings,

the site was planned to be all-electric, with space conditioning accomplished

by either resistance elements or heat pumps in a forced-air system.

Data on the energy consumption of each building collected during the

period of evaluation will be useful in determining if the predicted

values were adequate for use in the design process to compare alternate

service designs.

Environmental Study

Environmental studies should need certain TS operational information

dependent upon the type of pollution monitoring techniques selected.

The TS environmental information should fall into two basic categories

which are: stack pollution and cooling process water drift (moisture

and chemical precipitate). The stack pollution analysis should require

information concerning plant operating schedules, equipment operation

time, maintenance records, fossil fuel burner adjustments, fuel characteristics and ambient air measurements. Cooling equipment process analysis

should require information concerning operating schedules, ambient air

measurements and equipment loads from the TS information.

Economic Study

TS maintenance expenses in the form of materials and labor should be

reported by the MIUS plant operators for life-cycle-cost studies. TS

energy consumption, taxes and insurance costs will also be needed for

this work. TS first-cost information should be separated into heating,

cooling, and site distribution system costs and aggregated for each

group into that for subsystem design, equipment and installation.

As described in Section 4, this cost data should be used to simulate

and evaluate the various relevant alternatives which investors in a MIUS are likely to consider.

Institutional Factors

Institutional factors should be identified as design and construction proceed. For example, regulations of the Maryland Department of

Natural Resources may limit the utilization of multi-purpose cooling

ponds as chiller condenser water sources, if the overflow will be a risk to the sensitive Zekiah swamp.

Reliability/ Availability

Individual TS equipment availability and reliability information should

come from plant operators' operation and maintenance logs. For complete

evaluation of the TS, these should be supplemented by the information

17
recorded to meet the service quantity and quality requirements and

by status monitoring devices. This study should be closely coordinated

with that for the maintenance requirements of equipment, since correct

and timely maintenance is an important factor in proper mechanical equipment

operation.

Maintenance Requirements

A review of the TS equipment maintenance requirements should be conducted

and a summary prepared. Alternate equipment requirements should be

reviewed to see if any improvements are possible. Service logs of

the TS equipment should be reviewed to determine if unexpected maintenance requirements (parts or labor) can be traced to any particular

equipment. Literature and product data should also be analyzed in those cases

3.4 SOLID WASTE MANAGEMENT SUBSYSTEM

3.4.1 Subsystem Definition

MIUS Perspective

The MIUS solid waste management subsystem was to provide complete refuse

removal services to all buildings assigned. The solid waste management'

subsystem was to process a portion of the refuse collected and create

low pressure hot water as supplemental energy to the MIUS plant. The

solid waste management subsystem was to remove to disposal all non- processed refuse. The buildings for which removal service is to be

provided ranged from single-family-attached housing to commercial establishments such as service stations and fast food stores. The estimated

weekly average refuse load was approximately seven tons per day.

Figure 3.4.1 depicts the solid waste management subsystem as one element of the MIUS. The boundaries of the MIUS-SWMS should be

as follows.

° The user interface for the SWMS should be the Dempster Standard

Universal trash container.

0 The interface between the county sanitary landfill and the SWMS

should be the residue container which an offsite cartman was to

pick up as required. In the future, St. Charles was to design

and operate a sanitary landfill within the confines of the St.. Charles community. The site under consideration was to be

located approximately 2 miles south of the MIUS Plant on Piney

Church Road.

° The MIUS interface for the SWMS should be the interior envelope

of the space which houses the MIUS-SWMS. All MIUS/SWMS interactions

should be monitored at this point.

18
19

Figure

3.4.1

SOLID

WASTE

SUBSYSTEM

FUNCTIONAL

DIAGRAM
° The SWMS ecological interface should consist of the areas immediately

surrounding this subsystem's many potential point sources of

environmental pollution. Examples of such potential point sources

are the incinerator stack and the route of the refuse collection

vehicle. Specific identification and location of these potential

point sources are not possible until the SWMS design is completed.

Subsystem Perspective

The solid waste management subsystem was to provide complete refuse removal

service to each building and was to process a portion of the refuse

to generate supplemental energy. In addition, the solid waste incinerator

was to process 5% solids sludge from the MIUS wastewater management subsystem.

The solid waste incinerator was also to dispose of spent lubricants which

may be mixed with the relatively large volume of incinerator auxiliary

fuel. Energy was to be recovered in the form of low pressure hot water which

was to be utilized by other MIUS utilities or vented to the atmosphere.

Each use should be monitored to properly credit the solid waste management

subsystem for the value of the recovered energy actually utilized. The

solid waste management subsystem was a potential customer for part of the

treated wastewater. Wastewater was to keep the primary combustion chamber

within design temperature limits and was to quench hot residues for disposal.

Figure 3.4.1 also is a schematic of the materials flow projected for the

MIUS solid waste management subsystem. For the purpose of these guidelines the solid waste management subsystem is defined between arrows #1

and #6. The purpose of Figure 3.4.1 is not to describe a paticular

subsystem design but to illustrate how the subsystem might operate and

identify points which should be monitored.

Solid wastes are to be generated in individual buildings. The custodial

staff or occupants at each building would have transfered the solid

wastes from the interior of the building to a refuse container which,

in most cases, would have been located outside the building (Arrow # 1)

An SWMS refuse truck was to pick up each full container on its collection

route (Arrow #2). The truck was to dump the solid wastes collected

from its collection route into a refuse feed system (Arrow // 3).

The refuse feed system depicted consists of a hopper which receives

the refuse from the onsite collection truck, a conveyor which transports

the refuse from the hopper to a short vertical chute, and a short vertical

chute with a series of two internal guillotine doors which measure a unit

volume of refuse to be placed into the hydraulic ram of the incinerator.

A premeasured volume of solid waste would have fallen from the vertical

chute into the hopper of the refuse hydraulic ram (Arrow # 4 ) . The incinerator system, as depicted, consists of: a hydraulic ram which would have

transfered the refuse from the short vertical chute to the incinerator

(a primary combustion chamber and after-burner section); a hydraulic

ram which would have pushed the processed solid waste (residue) out

of the base of the primary combustion chamber; and a heat recovery

unit which would have reduced the energy level of the flue gases to

20
a set level above dew point and created supplemental energy to sustain

the other MIUS subsystem utility services. Residue was to fall from

the hydraulic residue ram into the residue pit (Arrow #5). The residual

removal system depicted is a wet type, i.e., it was to use a liquid

to quench the residue. The liquid was to be treated wastewater. The

residue removal system would have consisted of a residue pit which

temporarily would have held the residue, a drag conveyor which was

to remove the quenched residue from the residue pit, and a wet residue

container which was to hold the quenched residue and its associated

water. The residue container was to be picked up by an offsite refuse

collection truck (Arrow #6). A roll-on container truck would have

most likely serviced this account. An offsite refuse collection truck

was to transport and dump the quenched residue at an offsite landfill.

3.4.2 Technical Issues to be Addressed by the Evaluation Plan

MIUS Perspective

The purpose of this section is to establish the guidelines for the

evaluation of the solid waste management subsystem as an integral

part of a Modular Integrated Utility System. The fundamental question

to be answered is "Are there any benefits from the integration of solid

waste management with other utilities in a small, on-site facility?"

Traditional municipal approaches usually do not practice any form of resource recovery and tend to be regional rather than small in size.

Subsystem Perspective

Another purpose of this section is to establish guidelines to evaluate

the MIUS solid waste management subsystem as an independently functioning

system. Unlike the system level evaluation, the MIUS integration points

should be identified and evaluated at this level to determine how they

benefit the solid waste management subsystem alone. There should be more emphasis on the individual processes which make up the solid waste

management subsystem. The question to be answered is how well did

the solid waste management subsystem address the needs of the service

area and perform under a given set of operating, financial, and design

constraints

Solid waste management consists of many sectors of technical responsibility. For these guidelines, four sectors should be monitored and

evaluated. The definition of these sectors should facilitate comparison

with conventional solid waste management. The first sector is the

quality and cost of refuse removal service. The MIUS utility is

responsible for the removal and transport of all solid wastes generated

in and around all buildings assigned and for the removal of residue

and unprocessed refuse (bulky waste) from the MIUS utility building.

The second sector is the refuse incineration. Here, there are six areas

of responsibility which should be monitored and evaluated. The solid

waste incinerator must comply with Maryland and Federal air pollution

21
laws on point source emissions. It must reduce the volume and weight

of the refuse charge as much as practical. (This is its primary function.)

It must also release the heat content contained in refuse with the

minimum practical use of supplementary energy. It must be able to

co-fire refuse with 5% solid sludges. It must dispose of spent lubricants

and other waste volatiles. It must have the flexibility to adapt to

treated wastewater in lieu of potable water to maintain the temperature

of the primary combustion chamber and to quench hot residue.

The third sector is support services. A significant number of the outages

and service reductions experienced by solid waste management facilities

such as incinerators and materials-recovery systems are the result of

failures in material-handling and support items. The performance (reliability,

capacity, efficiency) of items such as belt conveyors, hopper, hydraulic

rams, drag conveyors, containers, and guillotine chute systems should

be monitored and calculated The fourth sector is heat recovery which

should be monitored and evaluated. The heat recovery unit must transfer

as much energy as practical from the incoming hot flue gas stream to

the heat recovery loop in a form and quantity, and at a time compatible

with the other MIUS utilities.

3.4.3 Subsystem Data Requirements

MIUS Perspective

The quantity of refuse removed from each individual building, the type

of refuse collection for each building, and individual building descriptions

should be recorded to obtain an accurate determination of the utility

service provided by the MIUS-SWMS. The solid waste management equipment

in each building served by the MIUS-SWMS should be identified as to

type, performance, and design. Each individual building's solid waste

stream should be sampled, and ultimate, proximate, and bomb calorimetric

laboratory analyses should be performed on the field samples to achieve

accurate material and energy balances for the SWMS subsystem.

The evaluation of the technical performance on a systems level should

incorporate a determintion of items such as reliability of service,

ability to unobtrusively achieve its mission as an onsite utility, and

compliance with all Federal, State and Local laws and regulations. Data

should be required to support an analysis of the ability of the SWMS to

utilize treated wastewater, and of the ability of the thermal subsystem

to utilize the heat recovered from incineration. Treated wastewater was

to be used to quench the incinerator ash. Full utilization of the heat

recovered from incineration may require modification of the incinerator

operating schedule. The impact of these modifications should be assessed

as the operators seek to optimize system performance.

A cost analysis of the MIUS-SWMS utility service should include capital

design, installation, operating, and maintenance costs (incurred from

the user interface to the ultimate disposal point which is the landfill).

Cost elements include items such as individual building elements, handling

equipment, refuse collection equipment and MIUS-SWMS process equipment.

22
The actual day-to-day operation of the MIUS-SWMS should be correlated

with the ability of the subsystem to comply with the Ambient Air Quality

Standards. Maryland Air Pollution Regulations (10.03.35, Regulations

Governing the Control of Air Pollution in the State of Maryland, as amended ) define Ambient Air Quality Standards applicable to the MIUS-SWMS.

The Ambient Air Quality Standards regulate the emission of certain elemental substances as pollutants and also specify the conditions under which

the Air Pollution Episode System will go into effect.

Any interruption to the utility service provided by the MIUS-SWMS

caused by the air pollution episodes should be documented. The Maryland

Air Pollution Episode System consists of three stages of adverse meteorological conditions: Alert, Warning and Emergency. The impact of the

emission reduction objectives on the MIUS-SWMS by the Maryland Air Pollution Episode System for the Alert stage is to "Stop all incineration

except that resulting from public collection of refuse.” The Warning

and Emergency stages demand "Complete elimination of the use of all

incinerators .

The air pollution technology employed by the MIUS-SWMS to comply

with the Maryland Ambient Air Quality Standards should be measured for

comparison with relevant similar and alternate methods of implementing

the best state-of-the-art equipment. The Ambient Air Quality Standards

regulate the following pollutants: sulfur oxides; particulate matter;

carbon monoxide; non-methane hydrocarbons; photochemical oxidants; and

oxides of nitro.gen.

Subsystem Perspective

The thrust of the data to be acquired concerning the solid waste management

subsystem should be the documentation of the performance of an onsite

small-scale solid waste facility and its component technology over an extended period of time. Most equipment tests have a short duration.

The technology to be documented should be that of standard articles

of commerce. The evaluation should impartially document representative

packaged solid waste management equipment under field conditions. These

data should be in great demand to evaluate other similar installations

in the future as refuse disposal sites and fossil fuels become harder

to find.

The first set of data should pertain to the performance of the refuse

removal service provided to the individual site buildings and the MIUS

utility building. The data requirements for evaluating building refuse

removal service are addressed under MIUS Perspective.

23
The second set of data should pertain to the technical performance

of the solid waste incinerator. The incinerator emissions as previously

stated should be monitored and correlated with system load and environmental

conditions. The weight and volume of refuse before and after incineration

should be recorded to document the ability of the incinerator to reduce

the volume and weight of the refuse charge. There should be ultimate,

proximate, and bomb calorimetric analyses of the refuse charge, residue

and the supplementary fuel consumed to document the total heat released

by the incinerator. Peak and average sustained heat recovery efficiencies

should require time correlation of data on recovered heat and total

heat release. The impact on fuel consumption, volume and weight reduction,

air emissions, and heat release efficiency should be recorded during

periods of sludge processing. When spent lubricant and other waste

volatiles are diluted in or burned with supplemental fuel, the effects

on burner performance and air emissions should be recorded. If treated

wastewater is used to replace potable water as a means of thermal

regulation of the primary combustion chamber, the emissions and reliability

data should also be recorded. If treated wastewater is used to quench the

hot incinerator residue, its impact on overall SWMS subsystem performance

should be determined.

The third set of data should include information concerning the quality

of support services. Data such as on/off times, energy consumption,

maintenance, and failure data should be recorded for equipment items

mentioned earlier such as residue removal equipment and refuse feed

mechanisms. These data should be correlated with data on the total

system to differentiate failures due to support equipment from those

related to the incinerator.

The fourth set of data should include information concerning the recovery

of energy from the incinerator stack gases and its subsequent utilization.

The flow rate and enthalpy of stack gases entering and leaving the

heat exchanger should be recorded and compared with those of the heat

transfer media, which should be collected during the same time period.

Documenting the utilization of recovered energy is somewhat more difficult.

The uses of the energy recovered from solid waste can vary from drying

sludge and heating wastewater treatment processes to direct venting

to the atmosphere. This problem is further complicated by the fact

that a cascade heat utilization system is used (Figure 3.1.1). The

recoverable heat from solid waste is piped to a High Temperature Storage

device. From there it can either go to the WMS or to the Thermal

Subsystem to heat or cool the primary hot or chilled water loop. If

there is no need for this energy at the time, the energy can either

be vented to the atmosphere or stored in a low temperature Storage

device and used at a later time. It should be noted that MIUS will

also recover and utilize supplemental energy from the ESS. The actual

operation of the ESS, WMS, and the SWMS should be recorded. The enthalpies

of the High Temperature Storage and Low Temperature Storage devices

should be continuously monitored. By recording the recovered energy

vented to the atmosphere and the requirements for thermal energy on

a continuous basis, the relative contribution of the solid waste management

facility can be prorated from the total recoverable heat available

and the value of its benefit determined.

24
3.5 WASTEWATER MANAGEMENT SUBSYSTEM

3.5.1 Subsystem Definition

The MIUS Wastewater Management Subsystem (WMS) was to provide treatment

of the aqueous liquid wastes generated by the MIUS community and other

MIUS subsystems. System inputs were to include the wastewater to be treated

and the power input required for treating the wastewater. The wastewater

was expected to be domestic in nature because most of it originates from

the apartments, although a small portion can result from operation of the

solid waste, electrical and thermal subsystems. The power was to be supplied

by the electrical service subystem, and was to be mainly consumed for moving

the wastewater and the sludge streams through the treatment plant. After

being treated in a series of primary, secondary and tertiary processes,

the wastewater was to be discharged as a major system output, pumped either to

the MIUS Community for disposal by land application or to the thermal

subsystem for use as cooling water. Another system output was the sludge

resulting from the primary screening and the secondary biological treatment. The sludge was to be pumped to the solid waste subsystem where it was to be incinerated with solid waste. The treatment facilities, inputs

and outputs of the wastewater management subsystem as well as its relationship with the site and other MIUS subsystems are schematically shown

in Figure 3.5.1.

The primary treatment facilities for the St. Charles MIUS was to consist

of an equalization . wet-well and a set of rotary strainers. The wet-well

was sized for retaining the peak flow, whose rate is calculated as 2.5

times the average flow rate for 100 minutes. The wastewater was then

to be transferred by a pair of pumps and split into two streams, each

passing through a rotary strainer. The strainers were to remove coarse

suspended organic matter which is pumped to a sludge holding tank.

The liquid streams then were to combine and subsequently split and

fed into two biological rotary disc contactors.

Rotary biological discs and subsequent sedimentation tanks were the major

secondary biological treatment facilities. In the rotary disc contactor,

colloidal and soluble organic matter were utilized by microorganisms growing

on the disc surface and decomposed into inorganic matter or synthesized

into microbial mass. The biologically stabilized wastewater streams were to

flow into rectangular sedimentation tanks where biological solids were to be

separated from the liquid. Clear supernatant was to pass on to a subsequent

clear well while the solids were to be collected and discharged into

a sludge holding tank where they were to be mixed with the primary screenings.

The settled biological effluent was to be pumped from the clear well into

tertiary dual-media pressure filter units where remaining biological particles

were to be removed by filtration. The filtered water was to be temporarily

stored in one of the two elevated storage tanks and then pumped to a county golf course for use in spray irrigation. A small portion of the

treated wastewater was expected to be used as cooling water and in-plant

wash water. Periodically, the filter units were to be backwashed with water

pumped directly from the storage tanks. The wasted backwash water,

which contained the biological solids removed during the filtration period,

was to be discharged into the wet-well and treated with the raw wastewater.

25
26
3.5.2 Technical Issues to be Addressed by the Evaluation Plan

St. Charles provided an excellent opportunity to obtain full-scale performance information relevant to the design and operation of future MIUS

wastewater management subsystems. The MIUS-WMS was to have several unique

features, which resulted from its integration with the other MIUS subsystems.

Like most private wastewater treatment plants, the MIUS wastewater management

subsystem was to be a small facility which is more difficult to operate in

a manner which produces a consistently high quality effluent than is a large

municipal wastewater treatment plant. Unlike most treatment plants, the

MIUS-WMS was to be located near the center of the MIUS residential and

commercial areas. Any system failure could result in a tremendous loss

of residential and commercial activity. Therefore, its performance should

be more reliable than a wastewater treatment plant serving a subdivision

community. Successful performance of the MIUS-WMS is reflected not only

by a high' system efficiency or effluent quality, but also by the reliability

and availability of equipment. The MIUS-WMS should have adequate treatment

capability, sufficient flexibility and system monitoring equipment. However,

the system should not be wastefully over-designed, which invites an unnecessary financial burden. Hence, in addition to treatment efficiency and

effluent quality, equipment reliability as well as data collection relevant

to future system optimization should be included in the evaluation.

The MIUS-WMS is an integral part of the MIUS complex. Its performance and

service are highly dependent upon and also can affect the performance and

functions of the other MIUS subsystems. This interrelationship does not

exist for a normal wastewater treatment system serving a community, and

thus should be a prime target of the evalution. Outputs of the MIUS-WMS

which were to be utilized or accepted by other subsystems included the

treated effluent and sludge. The treated effluent was to be utilized to

quench the incinerator residue, as makeup to the primary and secondary

thermal loops, and as makeup to the condenser water loop. The remaining

effluent was not to be discharged directly to a surface receiving body

of water, but sprayed on a county golf course to provide the necessary

irrigation supply. The excess sludge was to be incinerated by the MIUS-SWMS.

The quantity and quality of the system discharges were not only limited

by regulatory agencies but were also dictated by the disposal capability

of the downstream subsystems. It is obvious that sufficient flexibility

should be provided in system design, and careful management should be

exercised to regulate this relationship. Hence, mass balances of the liquids

and solids transported across the subsystem boundary should be documented

and used in further analyses.

The MIUS-WMS was to accept excess heat from the thermal subsystem, and

use it to raise the wastewater temperature. This should result in a better

and more consistent treatment efficiency. The expected benefit of utilization

of excess thermal energy was attributed to the increase in treatment kinetics,

but more supporting data from full-scale plant operation are needed to establish

a practical benefit justifying the expense. At this time, there were no plans

to fire a boiler to provide heat to that MIUS-WMS when excess thermal energy

is unavailable. The erratic "dumping" of heat to the MIUS-WMS could have

a deleterious effect on subsystem performance. Hence, the reliability of the

heat source and its influence on wastewater treatment should be evaluated.

27
Additional objectives of the evaluation of the MIUS-WMS should be to

evaluate its performance as a wastewater treatment subsystem serving

the site and to collect performance data to be used in the design

and operation of future MIUS project.

3.5.3 Subsystem Data Requirements

For an evaluation of the performance of the wastewater management

subsystem, data should be collected on:

(1) The performance of the wastewater treatment system and the

major units;

(2) The reliability of the wastewater treatment subsystem and the

impact of subsystem failure (to identify the most critical

process or unit);

(3) System efficiency in connection with the utilization of waste

heat

(4) The quantity of treated wastewater and resulting sludge;

(5) The energy consumption of each major process of unit;

(6) The cost ef f ectivensss of the wastewater management subsystem;

(7) Flow rates and total flow of raw wastewater, plant effluent,

equalized effluent, treated effluent, filter backwash and

wasted sludge;

(8) Treatment efficiencies for removal of total and soluble organic

matter (BOD^, COD or TOC)'*', solids, nutrients and other constituents ; (9) The temperature of important internal wastewater streams using'

recovered heat;

(10) Parameters related to process control such as pH, dissolved

oxygen, sludge settleability , effluent turbidity, etc.;

(11) Subsystem reliability; and

(12) Operation and maintenance costs, as well as acquisition,

installation and construction costs.

3.6 BUILDING LOADS

3.6.1 Technical Issues to be Addressed by the Evaluation Plan

The evaluation of the building loads for the MIUS site should be accomplished

by individual metering of selected buildings and subcomponents of buildings.

The major loads for the large users (electrical, thermal, water and

solid waste) should be determined along with a statistically selected

sample from the small users. Wherever possible master meters should

be installed on groups of small-user buildings in order to determine

aggregate loads and load diversity. These load data should be analyzed

1 BOD^ - biological Oxygen demand (5 day)

COD - chemical oxygen demand

TOC - total organic carbon

28
statistically and employed to check the accuracy of the load prediction

programs used for evaluating the MIUS design. It is envisioned that

this effort should augument the existing data base to improve the design

methodology at future MIUS sites.

3.6.2 Data Requirements

The classes of data required for the building load analysis would

be: electrical load data, space heating load data, domestic hot water

energy and water data, lighting data for institutional and commercial

buildings, water (hot and cold) usage data, and solid waste generation

data by classification. The scheme for collecting this data is depicted

in Figure 3.6.1.

29
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Figure

3.6.1

SITE

UTILITY

LOAD

DATA

ACQUISITION

SCHEME
4. THE FINANCIAL/ECONOMIC EVALUATION PLAN

Any particular MIUS project can be evaluated by means of a number

of different criteria depending on the point of view of the investor and

his objectives [3-13]. Thus a proper evaluation of a MIUS requires specification of the viewpoint of interest; i.e., what type of investor is

expected to make the decision between a MIUS and conventional utility

services? Whether a MIUS is relatively more attractive than its conventional alternatives depends on the economic/financial environment of

the decision maker. What is required, then, for the economic evaluation

of a MIUS is a specification of the possible types of investors who are most likely to give a MIUS serious consideration. Four of the most significant candidates are: (1) real estate developers; (2) electric utility

companies; (3) state and local governments; and (4) the Federal government.

4.1 REAL ESTATE DEVELOPER VIEWPOINT

In the proposed MIUS project at St. Charles, a real estate development

company, Interstate Land Development, is the decision-making investor.

Such developers are likely to have an interest in MIUS as one solution

to the problem of sewer moratoria which have recently inhibited land

development in many districts [11-12], Moreover, MIUS offers land

developers a convenient avenue for their natural expansion into a new activity, but one which is closely related to their traditional areas

of interest. Research is needed to determine the investment criteria

most appropriate for such a real estate developer. Several approaches

should be explored. Those actually engaged in real estate development

as well as their accountants should be contacted. Other possible contacts

familiar with real estate developers' objectives can be found at such

institutions as the National Association of Homebuilders, the Urban Land

Institute, the National Association of Housing and Redevelopment Officials

and HUD.

In addition to the evalution criteria appropriate to the developers'

viewpoint, the alternatives and options available to developers must be

considered. If a developer would subdivide land and build residences,

he is legally required to supply wastewater treatment services to the

planned structures. The options to be considered by a developer depend

on whether or not a sewer moratorium exists in the area. If there is a moratorium, then there appear to be four alternatives facing the developer:

1. Not build and wait for the moratorium to be lifted.

2. Build the residences and service them with a package wastewater

treatment plant.

31
3 .

4.

Build the residences, service them with a package wastewater

treatment plant, and supply electricity and central heating

and cooling with a total energy plant. [Partial MIUS]^

Build and service all utility needs, including solid waste

disposal, with a full MIUS.^

One of the problems with using a MIUS in a moratorium area may be

the unavailability of a backup system for reliability.

On the other hand, if regional sewer and water are available, the

options facing the developer are different:

1. Not build and keep land in present use (agriculture).

2. Build residences and hook up to regional sewer, paying tap

fees and front footage fees, which are a function of distance

of the site from the nearest interceptor.

3. Build residences and service with a package wastewater treatment plant.

4. Build residences and supply with a package plant plus a total

energy plant [Partial MIUS].

5. Build residences and a full MIUS.

Each of these alternatives facing the developer will have to be

evaluated to the extent possible by separate accounting of the capital,

operating and maintenance costs of those utility subsystems which can

be considered "marginal". These costs will have to be measured as incurred by the developer. Thus one area of investigation concerns the

point at which metering and charging for all utility services takes

place. For example, the major commercial stores would be individually

metered for electricity and thermal energy use, while electric service

is metered at each apartment but the heating and cooling are not.

It may be appropriate to consider three alternatives for solid waste

disposal

a) Normal refuse collection and disposal in a sanitary landfill;

b) A package incinerator system without waste heat recovery; and

c) A package incinerator system with waste heat recovery.

2 As noted in Subsection 3.3 above, it is also appropriate to compare

the actual MIUS with alternative total energy plants using different

prime movers and equipment, as well as with several remote-unit

configurations

32
4.2 ELECTRIC UTILITY VIEWPOINT

Another likely investor in a MIUS would be an electric utility

company. Since a MIUS would be at least partially in competition with

electric utilities, they can be expected to show some interest in the

possibilities offered by a MIUS. The viewpoint and financial evaluation

criteria of such utility companies should be studied and characterized

so that the attractiveness of a MIUS can be further assessed. Individual

utility companies should be contacted as well as industry associations,

such as the Edison Electric Institute (especially the EEI Task Force on Co-generation), and the Electric Power Research Institute.

Besides the evalution criteria used by utilities, there is a need

to consider the alternatives facing utilities. The electric utility

is legally required to supply power to all buildings within its franchise area. Thus, if a subdivision is being built, the utility can meet those needs in one of four alternative ways:

1. Utilize existing reserve capacity.

2. Purchase additional energy through the interconnected grid.

3. Produce more power by adding capacity.

4. Build a MIUS on the development site.

4.3 STATE AND LOCAL GOVERNMENT VIEWPOINT

State and local governments might also be interested in investing

in a MIUS either as a substitute for, or expansion of, their current

operations in public utility services or as a means of influencing the

pattern of growth and development within their jurisdictions. The

decision criteria of these governmental bodies with respect to a MIUS

investment must be specified. State and local authorities, such as the

Charles County Department of Public Works which holds the sewage franchise in the area should be contacted. The American Public Power Association

should also prove useful in determining the appropriate evaluation criteria

in this instance. The Maryland Public Service Commission and the National

Association of Regulatory Utility Commissioners should be able to provide

guidance in determining cost of service and the criteria for public

evaluation of a MIUS. One of the unique aspects of the viewpoint likely

to be taken by local governments is that the property taxes paid on strutures being served by a MIUS constitute a benefit in terms of

additional revenue (provided those structures could not have been built

•without a MIUS)

The basic question which State and local governments would ask is:

Does a MIUS represent a less costly way of providing wastewater treatment and solid waste disposal services than would the normal method of

supply through connection to or utilization of their regional facilities?

Can a MIUS provide necessary services at an earlier time? These questions can be approached by comparing the costs of service using a MIUS

with expansion of the conventional regional systems.

33
The significant alternatives which a State or local government

would likely be interested in evaluating would be the following:

1. Not provide wastewater treatment to the prospective

development

2. Provide wastewater treatment by expanding the capacity of

the existing regional system.

4.4 3. Provide wastewater treatment by building and operating a MIUS.

FEDERAL GOVERNMENT VIEWPOINT

The other viewpoint that should be taken is that of the Federal

government. Such a viewpoint is appropriate not only because investment

by the government indirectly through subsidies (or even directly as military or research facility) is a possibility, but also because justification of a federal program to encourage MIUS requires a social or national benefit/ cost evaluation. The literature in this area is truly

voluminous. General agreement among economists has been reached on the

appropriate methodology for such public project evalutions. Difficutly

arises, however, in the areas of the measurement of environmental effects

and the comparison of different distributions of costs and benefits among

the affected parties. One method of approximating the Federal government

viewpoint would be to evaluate the MIUS on the basis of its purely

economic merits — an approach which would involve measuring the

quantifiable benefits and costs of the projects in terms of its impact on the national welfare. Thus, MIUS would be evaluated independent of

such issues as the special financial constraints facing the developer

or utility company, and the income and indirect business taxes incurred

by the private developer.

4.5

OTHER INSTITUTIONS' VIEWPOINTS

Certain special applications of a MIUS might also be worth investigating. These would include large nonresidential facilities such as universities, research centers, hospitals, or military bases. The

institutions which operate such facilities may well have special interests

and objectives because of their non-profit or public status. Such objectives would have to be defined so that appropriate evaluation criteria

could be specified for each institution.

4.6

DATA COLLECTION

All of the data needed for the financial and economic evaluation of

the MIUS demonstration should be identified. The data should include both

physical quantities and price information on each service provided by the

MIUS. All of the cost items associated with the construction, installation, operation, and maintenance of the MIUS should be specified. In

addition, all of the revenue items from the services provided by the

MIUS should be identified and rate structures established for them.

34
Once these data needs have been identified and rate structures established

for them then a detailed format for collecting the data should be developed.

This detailed format should also permit separate data collection on a subsystem basis within the limits permitted by the separability

of the cost elements. An example of a cost item which should prove

difficult to assign to separate subsystems is fuel, since its benefits

accrue to both the electrical and solid waste management subsystems.

The separate cost and revenue data should be used to construct the

relevant alternatives discussed above, which the various investors in

a MIUS would be likely to consider.

35
5 . CONCLUSIONS

The successful evaluation of the MIUS will entail the formulation and

implementation of an evaluation plan along the guidelines established

in this report. This plan should specify the performance factors for

both the total MIUS and the individual subsystems; specify the data

requirements of the MIUS evaluation, identify critical system components,

develop analysis schemes and models for evaluting the MIUS performance,

and identify alternate utility systems for comparison. The evaluation

plan should be developed in close conjunction with individuals, groups,

institutions and agencies who will eventually be involved in the future

implementation of the MIUS concept.

The technical evaluation of the MIUS should consist of a system

evaluation of the total MIUS plant; evaluations of the electrical service

subsystem, the thermal subsystem, the solid waste management subsystem,

the wastewater management subsystem; and an evaluation of the building

loads, service demands and consumptions.

The financial and economic evaluation of the MIUS demonstration should

develop criteria depending on the viewpoint of potential MIUS investors

such as real estate developers, electric utility companies, state and

local governments and the federal government.

36
6 . REFERENCES

1. J. H. Rothenberg, "The Modular Integrated Utility Systems (MIUS)

Program," Eleventh Intersociety Energy Conservation Engineering

Conference Proceedings , September 1976.

2. Interstate Land Development, et_ al. , Preliminary Design Summary,

July 1977.

3. Benson, H. E. , and Monford, L. G. , Initial Comparisons of ModularSized, Integrated Utility Systems and Conventional Systems for

Several Building Types , NASA, April 1976.

4. Caceres, Luis Rene, "On the Relative Efficiency of Electric

Utilities,” Public Utilities Fortnightly , Vol. 99, No. 9,

April 28, 1977.

5. Call, William L. , "An Evaluation of Cost Standards for Joint

Products," The Engineering Economist , Vol. 20, No. 3, Spring 1975.

6. Christensen, L. R. , and Greene, W. H. , "Economics of Scale in U.S.

Electric Power Generation," Journal of Political Economy , Vol. 84,

August 1976.

7. Coase, R. H. , "The Theory of Public Utility Pricing and Its

Application," Bell Journal of Economics and Management Science , Vol. 1, No. 1, Spring 1970.

8. Lin, Steven A. Y. , "The Modified Interval Rate of Return and

Investment Criterion," Engineering Economist , Summer 1976.

9. Pingry, David E. , Energy Costs of Wastewater Reuse , Arizona

University

10. Solomon, Ezra, "Alternative Rate of Return Concepts and Their

Implications for Utility Regulation," Bell Journal of Economics

- and Management Science , Vol. 1, No. 1, Spring 1970.

11. Wendt, Paul F. , and Cerf, Allen R., Real Estate Investment Analysis

and Taxation , New York: McGraw-Hill Book Co., 1969.

12. White, John R. , "How Real Estate Decisions are Made," Real Estate

Review , Fall 1975.

13. Wiley, Robert J. , "Real Estate Investment Analysis: An Empirical

Study," The Appraisal Journal , Vol. XLIV, No. 4, October 1976.

14. Mitchell, David J., Performance Guidelines for a Modular Integrated

Utility System , National Bureau of Standards, NBSIR 77-1395,

November 1978.

37

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

U.S. DEPT. OF COMM. BIBLIOGRAPHIC DATA

SHEET

1. PUBLICATION OR REPORT NO. NBSIR 78-1563

2. Gov’t Accession

No.

3. Recipient’s Accession No.

4. TITLE AND SUBTITLE

GUIDELINES FOR EVALUATION OF A MIUS DEMONSTRATION

5. Publication Date December 1978

6. Performing Organization ( ode

7. AUTHOR(S) M.E.Kuklewicz

R. A. Grot, J.R. Schaefgen, D.J. Mitchell, A. C. Chao, S.R.% Weber,

8. Performing Organ. Report No.

9. PERFORMING ORGANIZATION NAME AND ADDRESS

NATIONAL BUREAU OF STANDARDS

DEPARTMENT OF COMMERCE

WASHINGTON, D.C. 20234

10. Project/Task/Work Unit No.

11. Contract/Grant No.

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

Department of Housing and Urban Development

Division of Energy, Building Technology and Standards

Office of Policy Development and Research

Washington, D. C. 20410

13. Type of Report & Period Covered

14. Sponsoring Agency Code

15. SUPPLEMENTARY NOTES

16.

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

bibliography or literature survey, mention it here.)

In order to obtain maximum benefits from a MIUS demonstration facility, a carefully planned evaluation should: assess the technical performance of the

MIUS demonstration plant, determine the public benefits of a Modular Integrated

Utility System (MIUS) ; show the viability of private ownership and operation of a MIUS plant, and provide a data base to support future analysis. This document

is a guideline for the development of a detailed evaluation plant for a MIUS

facility which was planned for demonstration at St. Charles, Maryland. The

generic types of technical, institutional, and economic issues are discussed.

General performance measures for the total system and each subsystem are indicated. The classes of data that will be required and the types of data analyses

to be employed are outlined.

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

)

Co-generation; integrated utility systems; solid waste management; thermal systems;

Total Energy; wastewater treatment.

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

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

C Order From National Technical Information Service (NTIS)

Springfield, Virginia 22151

19. SECURITY CLASS 21. NO. OF PAGES

(THIS REPORT)

45

UNCLASSIFIED

20. SECURITY CLASS 22. Price (THIS PAGE)

UNCLASSIFIED $4.50

USCOMM-DC 29042-P74
'

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