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OCR for page 25
2
History and Background
HISTORY OF DISTRICT HEATING
Urban district heating (although generally not cooling) has been
adopted outside the United States to an even greater extent than it
has in this country. More than 1,000 cities from Sweden to Italy to
the Soviet Union to Japan have district heating systems. In Western
Europe, in particular, such systems have flourished in recent decades.
District heating was initially developed in the United States (OTA,
1982; RDA, 1981~. Probably the earliest system was developed by
Benjamin Franklin in Philadelphia in the eighteenth century.
Franklin's system provided heat to several adjacent residences from a
central source. The world's first financially successful system was
developed in Lockport, New York. Designed in 1877 by Birdsill Holly,
the Lockport system provided steam from a central boiler plant to a
few nearby residences and other users.
By 1890, district heating systems were being rapidly installed in
numerous small cities and towns in upstate New York.
They soon spread
to other small cities in the United States, especially in northern
industrial states. They also spread to large cities, such as Chicago,
Pittsburgh, and Baltimore.
Most of the early systems distributed steam produced from a
reciprocating engine that was used primarily to generate electricity.
The early systems used the heat lost during the generating process to
produce steam. Electrical generators continued to be the principal
energy source for district heating well into the twentieth century.
For many utility-owned systems, district heating was a way to get
customers to connect to a centralized electrical generating system.
Previously, many customers had relied on their own onsite generator to
supply electricity and heat. For such systems, district heating was a
small and subsidiary part of the utility's business.
25
OCR for page 26
26
This arrangement was possible as long as power plants remained
small and located in town. In this century, however, turbines began
to replace reciprocating engines and technical advances reduced power
losses in transmission lines. These developments led to new, larger
electrical generating plants located farther from the centers of
cities.
These changes caused many urban systems to fail, beginning in the
late 1920s, as they lost their sources of nearby, relatively cheap
fuel. Other systems continued to provide steam, but at a higher
price. Urban systems continued to decline after World War II as
low-priced oil and natural gas began to be used for heating, and as
yet larger and more efficient power plants were located even farther
from the centers of cities.
In addition, urban renewal programs sponsored by the Department of
Housing and Urban Development (HUD) and its predecessor agencies often
unwittingly contributed to district heating's demise. Beginning in
the 1950s, older buildings in downtown areas were torn down and
replaced by modern structures. Many of the former were connected to
district heating systems; most of the latter have individual boilers
or were designed as "all electric" buildings. The decline of district
heating has been accelerated in the last decade by rising fuel costs
and the effect of air quality regulations that either require
expensive cleaning equipment or limit fuel choices. Taken together,
these developments have favored individual heating and cooling systems
for each building as opposed to the central systems that characterize
district heating and cooling.
In Rochester, New York, for example, the local investor-owned
utility system requested permission to discontinue its district
heating service in 1983. Over many years, urban renewal had gradually
eliminated most of its customers. The Rochester system had also been
subject to incremental pricing of natural gas, which made its price
too high for it to compete successfully with onsite systems.
There are relatively few commercial urban systems today selling
both steam and hot or chilled water in the United States. The number
has declined from about 250 in 1951 (Figure 2-1) to the 59 reported by
the Electric Power Research Institute (EPRI) in 1980 (RDA, 1981; OTA,
1982~. These systems contribute an insignificant amount of energy to
U.S. homes and buildings compared with the fossil fuels and
electricity used in individual buildings or properties.
EPRI surveyed the working urban district heating and cooling
systems in 1982. The survey found that the 35 reporting systems
delivered 0.065 quadrillion Btu of energy in 1982,* down from 0.095 in
1979. More than 75 percent of the fuel used to generate this energy
was premium oil and natural gas (IDHA, 19831. Most of the remaining
systems are older, deteriorating, and inefficient. Few are making
money (OTA, 1982~.
*Less than one-tenth of one percent of the 73.3 quads of energy used
in the United States in 1982. By comparison, the United States used
78.8 quads of energy in 1979 (DOE, 1983~.
OCR for page 27
27
~ ;> ~ :':..~
C4L\~L~ ~...4 ,~;~,V~ 7~
it, AR12. | N ~
ONT. _ ~_i
it,
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-a (_ :~:
TEXAS
FIGURE 2-1 Commercial district heating systems in the United States
and Canada in l9S1 (courtesy International District Heating Association).
OCR for page 28
28
Because of economic and environmental regulation, the
investor-owned electric utilities that operate most of these urban
systems have little incentive to maintain, upgrade, and modernize
their plant equipment or distribution systems. One current trend,
seen, for example, in Youngstown, Pittsburgh, and Rochester, is for
electric utilities to sell their district heating and cooling systems
to entrepreneurs who are not subject to state utility regulation (see
the Baltimore and Pittsburgh case studies in Appendix A). Other
systems, such as that in Chicago (Table 2-1), have stopped operating
altogether (OTA, 1982~.
THE RECENT REVIVAL
More recently, urban systems have undergone a revival of sorts in
several U.S. cities. Beginning in the 1970s, a series of government
and corporate-sponsored demonstration projects have contributed to the
revitalization of interest in district heating and cooling. New
systems have been built or old ones rehabilitated in cities such as
Provo, Utah, Lawrence, Massachusetts, and Baltimore, Maryland (see
Figure 2-2 and Appendix A). These systems have sometimes been known
by names other than district heating and cooling. They have often
relied on cogeneration and invariably have served more than one user.
Most are small-scale systems located in the centers of cities.
These and other new or revitalized systems have been funded in part
by a variety of HUD and Department of Energy (DOE) programs, including
HUD's urban development action grant (UDAG) program and a joint
HUD-DOE district heating and cooling assessment program (see Chapter
5) .
In addition, DOE began sponsoring cogeneration projects in 1977
that resulted in retrofitting power plants in central cities. These
cogeneration projects were typically tied to district heating and
cooling systems. Participating cities include Trenton, New Jersey,
and Piqua, Ohio, among others (see Figure 2-2 and Appendix A).
As a result, many private groups are either evaluating or designing
district heating and cooling systems for U.S. cities. Most have been
not-for-profit and municipally incorporated or owned. Some, like
those in Trenton and Baltimore, are being run by private
entrepreneurs. No new or revitalized system is operated by an
investor-owned electric utility.
A further boost to urban systems occurred when Congress passed the
Public Utility Regulatory Policies Act (PURPA) in 1978. PURPA
required electric utilities to purchase power from small producers or
cogenerators at rates equal to the "avoided cost" of generating
equivalent amounts of power by conventional means. This requirement
has helped to ensure a market and a price for electricity. In
addition, a few tax modifications in 1982 and 1984 have made capital
investments in district heating and cooling, as well as other
alternative energy systems, more attractive.
OCR for page 29
29
TABLE 2-1 Typical U.S. Steam District Heating and Cooling Utilities
Most Current
recent average
Percent of steam Losses in Fuels used, percent ORnef.'uxred p(r1~978)f
Ownership produced by sendout system, Number of Resid. Natural assets, steam
City of system cogeneration (103 Ib/hr) percent customers Coal oil gas percent (S/103 Ib)b
New York-Consolidated
Edison Investor 55 11,663 16 2,285 099 1 7.4 6.76
actual
(1 4,983)
maximum
possible
Chicago-Commonwealth
Edison Investor (Closed July 5, 1979-last 4 customers disconnected)
Philadelphia-Philadelphia
Electric . Investor 70 2,431 12 670 100 5.8 5.84
(3,857)
Detroit-Detroit Edison Investor 38 1,724 18 8434 9 87 - 7.0 5.26
(2,931 ) (#2)
Boston-Boston Edison Investor 0 1,975 21 465 76 24 10.3 7.05
(2,340)
Baltimore-Baltimore Gas
and Electric Investor 0 819 14 720 49 51 1.8 5.47
(990) (#2)
Indianapolis-Indianapolis
Power & Light Investor 46 1,428 15 70391 8 1 4.5 4.21
(1,722) (#2)
Lansing-Lansing Board of
Water ~ Light (Large) 0 260 12 488100 - 3.66
municipal (400) (loss of
S245,000
in 1978)
Virginia, Minn.-Virginia
Department of Public
Utilities (Small) 79 266 42 3,301100 75.0a 4.70
municipal (270) (70 percent
connection)
Piqua, Ohio-Piqua, Ohio
Municipal Power System ..... (Small) 100 42 6.5 8 100 Not2.10
municipal (80) available
aThev do not include generating plant in net assets of the steam system-they allocate it to the electric system.
bOne thousand Ibs of Steam has a heat content of about 1 million Btu.
NOTES: 1 Four largest systems in the United States are New York, Philadelphia, Detroit, and Boston. New York is by far largest in the United States and is
one of the largest in the world.
2Baltimore is a successful system with predominantly commercial customers, but is now owned by a private entrepreneur (see Appendix A).
31ndianapolis is a successful system with a large number of industrial customers.
4Chicago's system has been closed; they lacked interest in D/H and cogeneration and pushed electric heating in new buildings and nuclear power.
5Piqua is expanding by adding new hot water system (see Appendix A).
SOURCE: OTA (1982)
.
OCR for page 30
30
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OCR for page 31
31
THE CURRENT EXTENT OF DI STRICT HEATING
AND COOLING IN THE UNITED STATES
Until recently, little data was available to indicate the extent of
district heating and cooling systems in the United States. The data
that existed were scattered, difficult to correlate with other data,
and often unreliable. To a large extent, that is still the case.
In the last several years, however, several trade associations have
undertaken surveys to estimate the extent of district heating and
cooling in the United States. Most have dealt with the institutional
systems that have grown so rapidly in the last couple of decades.
These surveys are by no means exhaustive, but they seem to indicate
that the United States has more miles of district heating and cooling
pipes than any Western European country.
In one, the North American District Heating and Cooling Institute
(NADHCI) asked the U.S. Army Corps of Engineers to survey U.S. Army
installations. The Corps found more than 4,900 miles (7,900 km) of
district heating and cooling piping (U.S. Army Corps of Engineers,
personal communication to NADHCI, December 1982~.
Another recent survey of 2,000 U.S. colleges and universities found
2,157 miles (3,479 km) of district heating and cooling piping in
place, with an annual heat production of 337.5 trillion Btu (APPA
Newsletter, March 1984~. Another source puts the total number of
institutional systems at about 3,000 (NADHCI Newsletter, Spring 1984),
which may be a conservative estimate.
Assisted by NADHCI, the committee surveyed the Washington, D.C.,
and Baltimore metropolitan area to determine the number and types of
institutional systems currently operating. A total of 160 systems
were identified (see Appendix B). They include several college and
university campuses, the White House and other major government
buildings (Figure 2-3), the U.S. Capitol (Figure 2-4), downtown office
buildings, hospitals, residential complexes, and the National Zoo.
While the list is only a partial one, it illustrates the extent of
district heating and cooling in this metropolitan area.
THE EUROPEAN EXPERIENCE
District heating has had a different history in Europe than in the
United States. It has flourished in post-World War II Europe,
particularly in West Germany and Scandinavia (Figure 2-5~. Just as in
its early growth in the United States, district heating systems in
Western Europe arose and grew in response to a special set of economic
and technical circumstances.
District heating has become an integral part of the national energy
plans of almost all Western European countries (Table 2-2~. Energy
has traditionally been a more serious problem for Europe than the
United States. In fact, many European countries depend on foreign
OCR for page 32
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OCR for page 33
33
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OCR for page 34
34
(0 USSR
· 493,860
Chart from data
compiled by Oak Ridge
National Laboratory
20
o
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it_
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, WEST
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EDEN MARK
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1970~Z5 Q 198S
~?~
FIGURE 2-5 District heating growth in selected European countries,
1960-1980 (courtesy North American District Heating and Cooling
Institute).
OCR for page 35
Country Existing
Penetration
35
TABLE 2-2 Energy Contributions of District Heating and Combined Heat
and Power Systems in Selected Countries, 1981
Projections for Early l990s
Installed
Capacity of
District
Heating
(MW(th))
Connected
Load
(MW(th))
Industrial
Combined
Capacity
(MW(e))
Austria 4% of low
temperature end
use energy needs
5,500
Belgium 0.4% of useful 1,059 3,530
energy demand
for residential
space and water
heat
Denmark 42% of final
consumption for
residential
and commercial
sectors
40% of space
heating needs in
residential
and commercial
sectors
30% of single
family dwellings
50% of multi
family dwellings
0.76 million
dwellings
Finland
8% of total primary
energy
23% of space
heating needs in
the residential
and commercial
sectors and
38% of space
heating needs
in the industrial
sector
23,000a
9,500 5,500
OCR for page 36
36
TABLE 2-2 Energy Contributions of District Heating and Combined Heat
and Power Systems in Selected Countries, 1981 (continued)
Country Existing
Penetration
Projections for Early l990s
Installed
Capacity of
District
Heating
(MW(th))
Connected
Load
(MW(th))
Industrial
Combined
Capacity
(MW(e))
Germany 4-5% of residential
and commercial
energy demand
1.5 million
apartments
1.7 million nonresi
dential buildings
16% of space heating
needs in large
cities (population
above 100,000)
2% of space heating
needs in medium
sized cities
(population
10,000-100,000)
7% of low-temperature
heat demand
Ireland
Netherlands
Norway
Sweden 27% of space and
water heating
demand
47% of multi
family dwellings
3% of single
family dwellings
67,000b
5,000
100
16,000
100-150
2,500
25,000 1,200
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37
TABLE 2-2 Energy Contributions of District Heating and Combined Heat
and Power Systems in Selected Countries, 1981 (continued)
Country Existing
Penetration
Projections-for Early 1990s
Installed
Capacity of
District
Heating
(MW(th)) _
Sweden 16% (by volume) of
(continued) public and
commercial
buildings
United 1-2% of space
Kingdom heating demand
United
States
Connected
Load
(MW(th))
23,000C
1.5% of total 130,000
primary energy 200,000C
4% of space and
water heating
demand
including 1,800 MW(e) of combined production capacity.
"Midpoint of estimated range, 56,000-78,000 MW(th).
SLong-term technical potential only, not a market projection.
SOURCE: TEA, 1983.
Industrial
Combined
Capacity
(MW(e))
2,000-
3,000
33,000
countries for most of their energy supplies. Few have extensive
sources of oil or natural gas. Finland, for example, imports all
oil and natural gas it uses (IEA, 1983~.
About 40 percent of energy consumption in Europe goes for space
heating and hot water, a need that can be met most economically by
district heating. Indeed, it provides economies of scale in such
European cities visited by the committee as Copenhagen, Mannheim,
Paris, and Malmo, Sweden.
In general, the more well-established systems serving the larger
cities were initiated in the 1950s. They are highly integrated within
their communities and serve up to 98 percent of their potential
market. These systems are now focusing on improved energy efficiency,
often achieved through cogeneration, and on their competitive
positions. Small- and medium-sized cities generally began adopting
OCR for page 38
38
district heating in the late 1960s and early 1970s. These systems are
now planning to expand their distribution systems and service areas.
District heating has allowed European countries to mitigate their
urban air quality problems, which came to light in the 1960s and
1970s. District heating systems consolidated the individual heating
units of scattered residences, commercial centers, and industrial
plants into one centralized source. It is much easier and more
economical to control emissions from one power plant than from many
individual boilers.
In the 1970s, the Arab oil embargo spurred Europe to improve its
energy efficiency further to reduce its dependence on imported oil.
Several European countries began awarding government grants, loans,
and subsidies to encourage new district heating systems. Both central
and local governments adopted energy plans that emphasize cogeneration
plants to provide both heat and power.
District heating has also benefited from centralized planning. In
general, European political systems give greater authority to their
central governments than does that of the United States. Most
European countries have adopted national energy plans. Within each
country's national energy plan, municipal governments often have legal
authority to site industrial facilities and mandate the use of
district heating. In general, European district heating systems have
been developed in response to national or local energy plans or
incorporated into plans adopted later.
There are few district cooling systems in Europe. Some small
systems supply cooling, but no citywide systems now do. Most European
cities with district heating are located farther north than most major
U.S. cities. In addition, Europeans are generally not as accustomed
to air conditioning as Americans.
Nevertheless, air conditioning has been installed in many new
European office buildings, particularly in southern Europe, which
suggests that district cooling could be economically viable in many
European cities.
Analysts have cited six conditions that have fostered the growth of
district heating systems in Europe: densely populated urban areas,
cold winters, the technical ability to combine heat and power
generation, nearby cheap energy sources, high prices for imported oil
and gas, and utilities with the capacity to supply adequate heat and
power during long winters (Santini, 1981~.
Representative terms from entire chapter:
space heating
