Download Dipippo, R., 1988, International Developments in Geothermal Power Production: Geothermal Resources Council Bulletin, v. 17, no. 5, p. 8-19. 

NOTICE CONCERNING COPYRIGHT
RESTRICTIONS
This document may contain copyrighted materials. These materials have
been made available for use in research, teaching, and private study, but
may not be used for any commercial purpose. Users may not otherwise
copy, reproduce, retransmit, distribute, publish, commercially exploit or
otherwise transfer any material.
The copyright law of the United States (Title 17, United States Code)
governs the making of photocopies or other reproductions of copyrighted
material.
Under certain conditions specified in the law, libraries and archives are
authorized to furnish a photocopy or other reproduction. One of these
specific conditions is that the photocopy or reproduction is not to be "used
for any purpose other than private study, scholarship, or research." If a
user makes a request for, or later uses, a photocopy or reproduction for
purposes in excess of "fair use," that user may be liable for copyright
infringement.
This institution reserves the right to refuse to accept a copying order if, in
its judgment, fulfillment of the order would involve violation of copyright
law.
International Developments in
Geothermal Power
Product io n
by
R O N A L D DiPIPPO
Mechanica 1 Engineering Depart men t
Southeastern Massachusetts University
N o r t h Dartmouth, M A 02747
Abstract
Early Developments
Geothermal energy is recognized today as the only
one of the so-called alternate renewable energy resources
that has proven itself technically and economically, and
that is commercially available for electric power production. Seventeen countries now operate geothermal
power plants. The total installed capacity is 5 gigawatts,
with individual units ranging in size from a few hundred
kilowatts t o 135 megawatts. The identified but as yet
untapped reserves are measured in the tens of gigawatts;
the ultimate resource is immense. In this article, we trace
the origins of geothermal power, following its growth
from about the year 1900. We identify major milestones in
the development of the technology, present a snapshot of
the state of development around the world as of 1987 and
look to the future for possible growth scenarios.
Because the most common manifestations of geothermal energy are hot springs and steam vents, it is likely
that early humans used geothermal energy for various
simple purposes such as washing and cooking. Such uses
would surely predate written records. We will begin our
historical sketch with the advent of the modern age of
technology, Le., the age of the prime movers (Cardwell,
1972). Most people mark this period with Savery’s
invention of the steam-driven pump in 1698. This led to
Newcomen’s coal-burning steam engine in 17 12. Crude
but functional, Newcomen’s engine was improved by
others notably by Watt. By 1900, the steam engine had
reached a reasonable level of efficiency. At first, the
boilers were fired by wood or coal, and later by oil and gas.
Conti’s great contribution meant the elimination of the
need for the burning of any fuel.
It is important t o recogniie that Conti did not inject
geothermal steam directly into the cylinder of his engine,
but rather used the steam as the heating medium to boil
pure water. The clean steam generated in this process was
used to power the engine. The natural steam was too
contaminated for direct contact with the moving parts of
the engine. Conti’s first geothermal plant was, in today’s
nomenclature, a kind of binary plant - but one which
used water as the working fluid. The other important
difference between his binary plant and a modern one is
that his ran on a n open cycle whereas nowadays they
operate as closed cycles (Milora and Tester, 1976).
T h e field at Larderello proved so prolific that steam
could be won by relatively crude drilling techniques. Drill
rigs with percussion tools struck the shallow steam zones
in the volcanic formations. Rotary bits were developed
later to drill to deeper depths and recover higher temperature steam. Centrifugal separators were installed to
remove rock particles. Pipelines were designed and built
to convey the steam from wells to the power plants with
minimum losses. Valuable materials such as boron and
ammonia were extracted from the geothermal fluids i n the
process of power generation. The enterprise flourished
and the technology advanced ( E N E L , 1970).
Humble Beginnings
The “chuff-chuff-chuff” of the tiny steam engine went
unnoticed by the inhabitants of the small Italian town on
that Friday, 15 July 1904. But history was being made.
Geothermal energy was, for the first time, being harnessed
to produced electricity.
The place was a Tuscan town situated among rugged
hills that hissed and roared with the furious force of steam
issuing from deep within the earth. The inventor was
Prince Piero Ginori Conti, the son-in-law of Florestano
Larderel, himself a descendant of Francesco Lardel, the
executive manager of the original boric acid company
founded there in 1818. The town became known as
“Larderello.”
Thus, the operation of that tiny I O kilowatt ( k W )
dynamo, driven by a one cylinder engine fed with pure
steam raised in a boiler heated by geothermal steam,
marked the beginning of the modern geothermal age. For
more than half a century, Italy remained the only country
putting natural steam to use for power generation. During
that time, Italian engineers and scientists developed the
methods and the technology to improve the utilization of
this resource (Burgassi, 1987).
Page 8
Geothermal Resources Council BULLETIN May 1988
In the meantime, a few other countries, notably
J a p a n , New Zealand and the United States, began to
take notice of their geothermal resources (DiPippo,
1980). I n 1925, a small experimental plant was constructed at Beppu on the Japanese island of Kyushu. The
unit was rated at 1.12 kW; it was abandoned after a few
tests. Also in the 1920s, attempts were made to develop
The Big Geysers steam field in northern California and
the Imperial Valley in southern California, but neither
project proved successful. The first geological report on
the spectacular volcanic region near Taupo on New
Zealand's North Island was issued in. 1937, but development would not take shape for another 20 years.
T h u s by the time of World War 11, the onlygeothermal power plants in the world were at Larderello and the
surrounding towns. The installed capacity had grown to
132 megwatts ( M W ) by the end of 1943, and several
types of power systems were i n use depending on the
characteristics of the particular steam wells. They were:
( I ) direct-intake, noncondensing plants for newly
opened wells with high levels of noncondensable gases;
(2) pure-steam condensing units with a n integral reboiler
that permitted the venting or recovery of noncondensable gases as well as mineral extraction from steam
condensate; a n d (3) direct-steam units with condensers
and integral turbo-compressors for the removal of noncondensable gases. The units ranged in size from 600 kW
to 10 MW. The electricity from the Larderello plants
powered a large portion of the Italian railway system. I n
1944, practically the entire complex was reduced to
rubble by demolition squads of the retreating armies.
Only a tiny 23 kW training unit a t Serra77ano escaped
destruction. Within a year, the task of rebuilding the
plants had begun and new plants were added. Today,
Italy ranks fourth i n the world in total geothermal power
capacity. Several other fields are being explored and
developed i n a steady, systematic fashion.
In the 1950s. there was a resurgence of interest in
geothermal energy i n the United States, New Zealand
and J a p a n . This time the efforts were crowned with
success in each case. Exploration, drilling and testing
resulted i n the identification of several exploitable
reservoirs. Not far from Taupo, the Wairakei power
plant was built from 1956 t o 1963, giving New Zealand a
192,600 kW facility, the first ever t o be constructed at a
liquid-dominated reservoir. T h e Pacific Gas and Electric
Company ( P G & E ) inaugurated the geothermal age i n
the United States in 1960 with its 11,000 kW Geysers
U n i t No. I . In 1951, theJapaneseexperimented w i t h a 3 0
kW plant, the Hakuryu unit, near Beppu. In 1966, J a p a n
became the fourth country to put geothermal energy to
commercial use when the 22,000 k W Matsukawa plant
came on line.
The other pioneering countries in geothermal
power were: Mexico, which built a 3,500 kW plant a t
Pathe in 1959 (later decommissioned); the Soviet Union,
which built two small plants o n the Kamchatka peninsula in 1967; and Iceland, which built a small unit a t
Namafjall in 1968 (DiPippo, 1980).
Geothermal Resources Council BULLETIN M a y 1988
Growth Pattern
Figure I shows the growth in installed geothermal
power capacity from 1920 to the present. The first commercial-size unit came on line in 1913 at Larderello; it was
rated at 250 kW. Growth was very strong in the first few
decades, but settled down to a n average annual rate of 7.9
percent between 1944and 1960. From 1960 until 1978, the
average growth rate slipped slightly to about 7.6 percent.
Figure 1. Growth pattern for geothermal power:
installed megawatts versus year.
The most spectacular period of growth occurred
'om 1978 to 1985; the installed capacity grew at a n average annual rate of about 17.2 percent. During this period,
seven countries joined the ranks of geothermal power
producers, raising the number of countries from 10 to 17.
There is no question about the cause for this surge - the
two oil shocks that hit in 1973 and 1979. The first shock
spurred exploration for alternate, and in particular, indigenous and renewable energy resources; the second shock
intensified that effort and led to the construction of geothermal plants i n several countries seeking to reduce their
dependence on imported oil and petroleum products.
In the United States, the dramaticjump in the price of
oil had a very positive effect on geothermal development.
At The Geysers, PG&E buys the geothermal steam it uses
in its plants from the resource developers; the price is
determined by a formula that incorporates the price for
electricity generation by fossil and nuclear plants for the
previous year Dutcher, 1976). For the years just prior to
the first oil shock, PG&E had been paying about 0.27
mill/ kWh; in 1973 and 1974, it paid a n average of 0.34
mill/ kWh. In 1975, the price jumped to 0.739 mill/ kWh.
This had a synergistic effect; more revenues for the
resource developers meant more exploration and drilling
at the same time that utilities were trying t o move away
from conventional oil-fired plants. Thus, more and larger
plants were built at The Geysers while other areas in the
country began to be developed, notably in the Imperial
Valley.
Page 9
The countries of Central America (DiPippo, 1986)
along with .Japan (Mori, 1985) and the Philippines
(Tolentino and Buning, 1985), all heavily dependent
u p o n foreign sources f o r their oil requirements,
embarked on essentially crash programs to exploit their
abundant indigeous geothermal energy resources.
In this crisis atmosphere, much was accomplished.
The resource base was defined, methods of production
and conversion were developed and improved, and international industry took shape, and many prospered. People a r o u n d the world were afforded the benefits of
reliable and inexpensive electricity, generated with
minimal negative impact on the environment. Countries
that are blessed with natural geothermal deposits now
look to geothermal energy as a n important component
i n their mix of generation sources. The integrated use of
hydroelectric and geothermal plants is particularly a t tractive for many countries.
The essential role played by the United Nations as a
catalyst for geothermal development must not be overlooked. I n 1961 a n d again in 1970 and 1975, the U.N.
sponsored landmark symposiums that brought together
the world’s experts on geothermal energy. The proceedings of these conferences form enduring references for
those interested in the subject (United Nations, 1964,
1970, 1976). Besides these meetings, the U . N . funded and
conducted reconnaissance studies in the 1960s that ultimately led to development projects in El Salvador, Turkey a n d Chile. During the 1970s, similar efforts resulted
i n projects in Kenya, Nicaragua, Ethiopia a n d India. All
together, the U.N. has undertaken more than 30 projects
i n 20 countries throughout Europe, Asia, Africa, Central America, a n d S o u t h America. This important work
is continuing today with the cooperation of third-party
countries (Italy, J a p a n , Norway, and Sweden) that provide financial a n d technical assistance for particular
projects (Berejick, i n press).
Technical Milestones
Leaving aside the aforementioned pioneering works
carried out i n the early 1900s, the state of the art in
geothermal power development has been advanced by the
contributions of many individuals and companies from
several countries. In this section, we highlight some of the
most significant accomplishments.
First Deep Well at The Geysers
In 1955, B.C. McCabe formed the Magma Power
Company and successfully drilled the first deep well (Magma No. 1) at The Geysers steam field in northern California (Anderson, 1986). The well was 249 m (817 ft.)
deep, produced 18.9 kg/ s ( 1 50,000 lbm/ h) of dry steam at
a wellhead pressure of 790 k P a ( 1 14 Ibf/in2),and had the
capability to generate about 7 M W of electric power.
Although it had been known since 1925, when a few
shallow wells were drilled a t The Geysers, that this was a n
excellent resource, Magma I really marked the beginning
of its commercial phase of development.
Page 10
First Commercial Plant at a LiquidDominated Reservoir
In 1958, the first turbine-generator unit, rated at 6.5
M W, was commissioned at the Wairakei power plant on the
North Island in New Zcaland. I t was followed by 12 more
units over the next 5 years, bringing the total installed
capacity to 192.6 M W. Since the geofluid was a mixture of
steam (and other gases) and liquid (mostly water but with
a number of dissolved solids), a n elaborate fluid gathering
system was required to process the mixture in order to
separate the steam from the rest. An array of separators,
flash vessels, holding tanks, silencers and pipelines were
designed and constructed for this purpose. These designs
became accepted as industry standards for numerous
other plants around the world and established the New
Zealanders as among the chief geothermal experts (Thain
and Stacey, 1984).
First Geothermal Power Plan2
in the United States
On 25 September 1960, the PG&E commissioned its
Geysers linit I , an 1 I MW dry-steam plant (Bruce,
1964). The capital cost was $182/ kW; the plant is still in
operation. Although the technology needed to t a p the
steam field was not highly sophisticated, the significance
of Geysers I lay i n establishing confidence a m o n g utilities in geothermal energy as a reliable and inexpensive
source of electricity. This pathfinder power plant was
recognized by the American Society of Mechanical
Engineers in October 1985 as a National Historic
Mechanical Engineering Landmark. Today, PG&E operates 19 units at The Geysers, having a combined installed
capacity of I ,36 I M W. Furthermore, there are five other
utilities or companies involved at T h e Geysers either
operating or constructing plants, with a total capacity of
557 MW.
First Large Binary Geothermal Plant
I n September 1979, the Magmamax Power Plant
(now named the B.C. McCabe Unit I ) began operating
at the East Mesa geothermal field in California’s
Imperial Valley. The plant uses a process developed and
patented by the Magma Power Company (U.S. Patent
No. 3,757,5 16) which involved pumping the hot geofluid
o u t of the reservoir, maintaining pressure to prevent
flashing, passing the liquid through a bank of heat
exchangers in which a secondary working fluid (isobutane) is evaporated, and then returning the cooled
geofluid t o the reservoir by means of injection wells. The
secondary fluid passes through a more-or-less conventional, closed Rankine cycle. T h e plant was rated at a
nominal 10 MW. Although the original design was not
entirely successful (subsequent modifications have significantly improved performance, Hinrichs, 1984), this
plant served as proof of concept, proof of engineering
viability, and led t o a variety of types of binary plants,
both larger and smaller, which are now in operation at
many sites. T h e chief advantages of a binary-type plant
Geothermal Resources Council BULLETIN M a y 1988
Table 1. GEOTHERMAL POWER PLANTS O N LINE AS OF 1987
Type of Power Plant
Dry Steam
NPU
MWe
Country
United States
1-Flash
NPU
MWe
2-Flas h
NPU
MWe
28
1918
4
5
1365
Philippines
0
0
23
894
0
Mexico
2
10
9
175
5
0
470
41
499.7
1
45
1
22
6
88 1
2
0
105
0
0
0
85.25
0
1
100
9
1572
2
60
1
35
1
2
0
3
4
45
11
0
0
1
1
35
0
1
20 6
0
3
0
Italy
Japan
New Zealand
El Salvador
0
3
0
0
Indonesia
Kenya
Iceland
Nicaragua
Turkey
China
Soviet Union
France (Guadeloupe)
Portugal (Azores)
Greece
TOTALS:
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
-~
75
2534.95
6
45 5
4 886
1
11
0
1
0
3
1 _ _2
_
65
1411.586
0
I
0
0
0
9
0
MWe
111.85
92
221 1 85
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
23
894 0
0
0
6
0
0
0
0.7
0
0
0
0
0
0
________
917.9
Totals
NPU
55
0
0
0
28
1
42
0
0
0
0
_____
27
Binary
NPU
MWe
61
106.55
16
655 0
42
504 2
9
215 1
10
1672
3
4
95 0
87 25
3
45 0
5
39 0
1
35 0
1
20 6
15
14 586
1
11 0
1
42
1
30
1
____
20
228
5003.986
N O T E S : NPU = Number of Power Units; MWe = Installed Megawatts-electric
Totals include plants under construction and scheduled for completion i n 1987.
Table 2. GEOTHERMAL POWER PLANTS UNDER
CONSTRUCTION OR I N ADVANCED PLANNING
Country
United States
Philippines
No. Units
49
3
Total MWe
435.74
147.5
Mexico
15
370
Italy
19
555
4
138
Japan
TABLE 3. GEOTHERMAL POWER PLANTS
IN THE UNITED STATES
Plant Location
No. Units
Total MWe
The GeysersICA
28
19180
East Mesa/CA
27
36 5
Salton Sea/CA
2
44 5
HeberiCA
2
94 0
MammothlCA
2
70
WendelICA
2
06
CosoICA
1
27 0
PunaIHI
1
30
New Zealand
4
116.2
El Salvador
5
75
Indonesia
5
275
Wabuska / NV
2
12
Nicaragua
1
35
BeowaweiNV
1
170
Soviet Union
4
80
Brady/NV
Portugal (Azores)
1
10
Steamboat I NV
Costa Rica
1
55
Guatemala
1
15
Romania
India
1
1
TOTALS:
114
Geothermal Resources Council BULLETIN M a y 1988
1
1
1754.44
1
60
10
190
Desert Peak/NV
1
90
Soda LakeINV
3
2 75
Empire Farms/NV
4
36
Milford/UT
1
20 0
Cove Fort/UT
4
TOTALS:
92
27
221 1.85
Page 11
are its ability to use relatively low-temperature fluids
(thereby increasing the number of geothermal fields that
may be considered for electric power generation) and the
very low impact on environmental quality (owning to the
closed-loop nature of the operation).
listings of plants, country by country, are given in Tables
3-18. The geographical distribution of plants and promising sites are depicted on Figures 2-19.
These tables and figures are self-explanatory and
require no further elaboration.
First Plant to Operate Successfully
on Hypersaline Brines
Power Plant Performance
I n J u l y 1982, the Salton Sea Geothermal Electric
Project. a 10 M W flash plant, started producingelectricity
from brines that contained about 230,000 ppm of dissolved solids (Moss and others, 1982). These brines has
been nortorious for causing severe and rapid scaling of
pipes and other equipment. Although these brines were
h o t , roughly 246OC (475OF), they had resisted
exploitation until the Salton Sea plant came along. The
milestone development that led to the success of this plant
was the adoption of flash-crystallizer and reactor-clarifier
technology to the handling and treatment of the brines
(Featherstone and Powell, 198 I). It now appears technically feasible to exploit the vast resource, estimated at 3,000
M W, at the Salton Sea geothermal field. Larger plants are
now in operation and under construction utilizing the new
technology (Hodgson, 1985).
State of Geothermal Development Worldwide
Table I summarizes the state of geothermal power
development around the world as of this writing (mid1987). Table 2 shows where plants are either under construction or in the advanced planning stage. Detailed
I
By “performance” we mean: efficiency and reliability.
The former is a measure of how well the plant converts the
available energy in the geofluid to electricity; the latter is a
measure of the amount of time the plant is u p and producing or ready to produce power. I n general, geothermal
plants score very well on both counts.
It is not possible to present performance figures on all
the plants listed under the previous section in this article
(even if data on all plants were available); however, a few
plants merit special attention.
With regard to dry steam plants, we may focus on
those at The Geysers. The efficiency of the plants is often
characterized by a specific steam consumption of about 8
kg/ kWh (18 Ibm/kWh). This measure may serve a purpose at a particular field (where steam conditions are
reasonably uniform), but is a poor measure when plants at
different fields are compared. A consistent and thermodynamically correct method is to use the utilization efficiency based on the Second Law of Thermodynamics
(DiPippo and Marcille, 1984). O n this basis, PG&E
Geysers Unit 14, for example, has a n efficiency of 56.3
percent; it consumes 7.45 kg/ kWh (16.4 Ibm/ kWh) of
saturated steam at 179°C (355°F). The efficiency is
relative to a dead state at 18.3”C (65” F). These figures are
typical for PG&E units.
I
Figure 2. Geothermal plant sites/prospects in the United States General note for Figures 2-1 9 Geothermal sites
are denoted by filled-in circles, cities by open circles
Page 12
Geothermal Resources Council BULLETIN M a y 1988
Plant/Location
No. Units
Total MWe
Plant/Location
No. Units
Total MWe
Tongonan/Leyte
4
1150
Cerro Prieto I/Baja CA
5
180.0
2
220.0
TiwiiLuzon
6
330 0
Cerro Prieto II/Baja CA
Mak-Ban / Luzon
6
330 0
Cerro Prieto III/Baja CA
2
220.0
7
-
1150
Los Azufres/Michoacan
7
-
35.0
23
894.0
Palimpinon/S Negros
TOTALS:
16
TOTALS:
655.0
Manila
MAKl LI NGBANAHAW
LEYTE
Figure 4. Geothermal plant sites/prospects in Mexico
PAL1MPINON
d-4
-
0
c?*
Florence
300
LARDERELLO
Scale, km
MONTE AMlATA
ACQUAPENDENTE
TORRE ALFINA
~ C I M I N I
Plant/Location
No Units
Total MWe
34
429 7
Travale /Tuscany
3
48 0
Mt Amiata/Tuscany
3
22 0
Latera / Lat iurn
1
45
41
504 2
LarderelloiTuscany
TOTALS
-
0
Figure 5. Geothermal plant sites/prospects in Italy
Geothermal Resources Council BULLETIN M a y 1988
Page 13
I t is interesting to compare these results with those of
the S M U D G E O No. I plant, owned and operated by the
Sacramento Municipal Utility District ( S M U D ) , also
located at The Geysers. This plant has an efficiency of 70.2
percent and consumes 6.17 kg;kWh (13.6 Ibm, k W h ) of
slightly superheated steam. The S M U D G E O unit is
designed for high efficiency because the price S M U D pays
for its steam is commodity based, Le., dollarlmass of
steam, and therefore S M U D can afford to build a more
efficient (and more costly) plant so as to extract a higher
fraction of the available energy of the steam. As mentioned earlier, PG&E pays for its steam on a dollar/ kWhgenerated basis which leads to a different optimum plant
cost and a different (less efficient) design.
The entire PG&E geothermal power plant complex
(19 units, 1,361 MWe) recorded a n adjusted capacity
factor of 81.4 percent for the year 1985 (Williams, 1986).
In the first year of its operation (Dec. 1983 - Nov. 1984).
the S M U D E G O N o . 1 plant achieved an adjusted capacity factor of 93.6 percent. This “adjusted” capacity
Table 8. GEOTHERMAL POWER PLANTS IN NEW ZEALAND
Plant/Location
Wairakei/North Island
Kawerau/North Island
TOTALS:
167.2
Table 7. GEOTHERMAL POWER PLANTS I N JAPAN
Plant/Location
No. Units
Total MWe
Matsukawa/Honshu
OtakeiKyushu
OnumaiHonshu
Ontkobe/Honshu
Hatchobaru I/Kyushu
Kakkonda I/Honshu
Suginot /Kyushu
Mori/Hokkaido
Kirtshima / Kyushu
22.0
12.5
10.0
12.5
55.0
50.0
3.0
50.0
0.1
TOTALS:
9
215.1
0
200
Scale, hm
OHAAK I
MOKAI
WAlRAKEl
MOR1
*
ONUMA---,
MATSUKAWA
KAKKONDA I
KAKKONDA II
ON IKOBE
Figure 7. Geothermal plant siles/prospects In New Zeaiand
Tokyo
00
=~\--KIRISHIMA
P .
,
.
,
500
I
Scale, km
Figure 6. Geothermal plant sites/prospects in Japan.
Table 9. GEOTHERMAL POWER PLANTS
I N CENTRAL AMERICA
Plant/Country
Ahuachapan/El Salvador
Momotombo I/Ntcaragua
TOTALS:
Page 14
No. Units
Total MWe
3
95.0
125
1
4
130.0
Figure 8. Geothermal plant sites/prospects In Central America
Geothermal Resourres Council BULLETIN M a y 1988
facto r t a k e s i tit o a cc o u n t c it rt a i 1me n t s ordered b eca use
of excess hydroelectricity generation in the system.
With regard t o flash-steam plants, the slate of plants
i n .Japan makes for a n interesting study. There are nine
plants o n line(SeeTable7),eight ofwhichare flash plants
(six single-flash, two double-flash). T h e six single-flash
plants have a combined capacity of 88. I M W: the two
double-flash plants generated 600,697,167 kWh, yielding
a capacit!, factor of 77.8 percent; the double-flash plants
(Hatchobarii a n d Mori) produced 637,134,000 kWh, for a
69.3 percent capacity factor. The Hatchobaru plant operated 100 percent of the time and had a capacity factor o f
94.2 percent (Mori. 1985). .Thcrmodynamicallp. the Kakkonda single-flash plant operated at 50 M W and required
70 kg: kWh (IS4 Ibm,’ kWh) ofgeofluid, 14 percent (wt) of
which is steam. The utiliration efficiency is 20.7 percent.
The Hatchobaru double-flash plant operated at 55 M W,
required 17 kg, kWh (37.5 Ibm, kWh) of geofluid, 33 pcrcent (wt) of which is steam, and had a n efficiency of 53.8
perce nt.
Table 10. GEOTHERMAL POWER PLANTS I N INDONESIA
Table 12. GEOTHERMAL POWER PLANTS I N ICELAND
Plant/Location
Plant/Location
Kamojang /Java
Namafjall/Myvatn
Krafla /Myvatn
Svartsengi/ Reykjanes
Dieng/Java
TOTALS.
87.25
TOTALS
39 0
I
.
i..
‘JALL
I C E L A N D
,
0
1000
1-
SVARTSENGI
Scale. km
100
- O
Scale, km
Figure 9. Geothermal plant sites/prospects in Indonesia
Figure 11. Geothermal plant sites/prospects in Iceland
I
1
Table 11. GEOTHERMAL POWER PLANTS I N KENYA
Piant/Location
OlkariaiRift Valley
I
I
No. Units
1
I
Total MWe
450
I
I
Table 13. GEOTHERMAL POWER PLANTS I N TURKEY
Plant/Location
No. Units
Total MWe
1
20 6
KizildereiW Anatolia
CANAKKALE-TUZLA
/LAKE ASSAL (DJIBOUTI)
,-LAKE
LANGANO (ETHIOP(A)
r-TFNni’lRFK
Y
-Ankara
OLKARIA (KENYA)
~,
MBEYA (TANZANIA)
c
NEMRUT
LAY
D I N-GERMENCIK
0
500
1000
1
Scale, k m
Figure 10. Geothermal plant sites/prospects in Africa
Geothermal Resources Council BULLETIN M a y 1988
Figure 12. Geothermal plant sites/prospects in Turkey
Page 15
percent. A performance test conducted o n 6-7 March
showed the plant generating 0.755 M W (gross), 0.513
MWe(net),consuming363 kg/ k W h ( 8 0 0 I b m / k W h ) , a n d
having a utilization efficiency of 19.3 percent (net).
It is worth noting that the overall utilization of a
resource can be improved by the use of hybrid plants.
Such plants may combine geothermal and fossil energy
sources (Kestin and others, 1978), may integrate singleand double-flash plants( DiPippo, 1978), o r may combine
direct-heat uses with electric power production (DiPippo,
1987). While plants of this sort will always be advantageous thermodynamically, practical considerations may
restrict their application.
Table 14. GEOTHERMAL POWER PLANTS I N CHINA
Plant/Location
No. Units
Dengwu /Guangdong
o 586
Huailai/ Hebei
0 20
010
0 30
30
0 20
Wentang/Jiangxi
Huitang/Hunan
Chingshui /Taiwan
Xiongyue / Liaoning
Yangbajing/Xizang
100
ZhaoyuaniShandong
0 20
TOTALS
14.586
15
UZON-GEYSERNY
SEMYACHINSKY
NALYCHEVSKY
PARATUNKA
DENGWU
KOSHELEVSKY
Figure 13. Geothermal plant sites/prospects in China
KHODUTKINSKY
Scale, krn
(A)
Table 16. GEOTHERMAL POWER PLANTS I N GUADELOUPE
Plant/Location
No. Units
La Bouillante/Basse Terre
I
1
I
Figure 14a. Geothermal plant sites/prospects in the Soviet Union
Kamchatka Peninsula
Total MWe
42
I
1
With regard to binary plants, there are fewer t o
examine as to performance. The world's largest plant, the
Heber Demonstration Plant, has yet to achieve full output
due t o lack of brine supply. T h e specifications indicate
that the plant should r u n a t 7 5 k g / k W h ( l 6 5 l b m / k W h ) o f
brineat 182"C(360"F)and produce46.6 MWe(net) from
70 M W (gross). This would represent a utilization efficiency of 33 percent (net). To date, the maximum reported
output was as follows: 22 M W (gross), 10 M W (net), on a
brine flow of 441 k g / s (3,500,000 I b m / h ) at 181°C
(358" F),(Solomon and Berning, 1987); this corresponds
to a n efficiency of 15.8 percent (net).
At the other end of the size spectrum, wc may
examine the600 k W unit a t Wabuska, NV. Data have been
reported for the period August 1985 through March 1986
(Culver, 1987). The system (Le., plant, well and auxiliaries) was available for 4,999.4 hours out o f a total time of
5,832 hours, for a n availability factor of 85.7 percent. T h e
plant produced 2, I I7 M Wh, for a capacity factor of 60.5
Page 16
I
CORVO
o--
2
FLORES
TERCEIRA
FAIAL
$
&
=
PlCO VERMELHO
SA0 MIGUEL
O d 5
Scale, km
2
SANTA MAR IA
Plant/Location
I
Total MWe
No. Units
Pauzhetka/Kamchatka
I
1
I
11.0
I
Geothermal Resources Council BULLETIN M a y 1988
"
,--.
s.
R O M A N I A
Bucharest
^"K
0
,
I-
I
*--
\
1
BULGARIA
Figure 14b. Geothermal plant sites/prospects in the Soviet Union
Caucasus region
150
, , , O
Scale, hrn
Figure 17. Geothermal plant sites/prospects in Romania
Plant/Location
No. Units
Total MWe
,---PUGA
Pic0 Vermelho/Sao Miguel
1
30
MANIKARAN
c/J
Table 18 GEOTHERMAL POWER PLANTS I N GREECE
I
1
Plant/Location
I
No. Units
I
Total MWe
Milos
VALLEY
New Delhi
I
GRABEN
ARGENOS (Lesbos)
Figure 18. Geothermal plant sites/prospects in India
The Future For Geothermal Power
0
290
Scale, km
Figure 16. Geothermal plant sites/prospects in Greece.
Geothermal Resources Council BULLETIN M a y 1988
We may estimate the growth of geothermal electricity
over the next 5 years with the help of Table 2. T h e plants
listed there should be o n line within the next 5 years in
most cases. I f we allow for the usual delays and take only
7 5 percent of the expected new capacity. then about I ,3 15
M We should be added by the year 1992. That would bring
the total installed worldwide capacity to roughly 6,320
M W by then. The average annual growth rate over the
next 5 years would thus be about 4.8 percent. T h e actual
growth rate will depend o n the world price of oil. I f the
price remains relatively low, i.e., $15-181 bbl, then the rate
Page 17
is likely to be less than 4.8 percent. If the price jumps
abruptly to. say, $25-30’ bbl, then there might be economic
.justification to accelerate construction of geothernial
capacity. and the rate could climb to over 6 percent. If all
the new capacity listed in Table 2 were to come on line in 5
years, the growth rate would be 6.2 percent.
Over the next 5 years, the ranking of the countries
involved in geothermal power will change. Using Table 2 as
a guide, the United States will retain its leadership with
about 140 units o n line producing roughly 2,650 M W. This
will account for nearly 40 percent of the total geothermal
power on line in the world, down 4 percentage points from
the present. Italy may return to the second position, closely
followed by the Philippines and Mexico. These four
leaders will account for roughly 85 percent of all geothermal power capacity and 76 percent of all geothermal
power units. There should be 21 countries on the list in 5
years, the f o u r new additions being Costa Rica,
Guatemala. Romania and India.
A
SOURCES CHAUDES (HAITI1
GRAEEN DE ENRIQUILLO (OR 1
LA BOUILLANTE [GUADEL I
rSOUFRIERE
ILALO-CHALAPAS (ECU I
SOUTH
AMERICA
IST M I A 1
\
CHACHANI-LffiUNA SALINAS (PERU)
CALACOA- TUTUPACA CHALLAPALCA (PERU)
-
LAGUNA COLWAOA (BOL 1
EL TATlO (CHILE)
COPAHUE (ARGl
lowing people were very helpful in providing information:
H. Alonso E. (CFE), D.N. Anderson (GRC), K . Boren
(GeoProducts), D.F.X. Finn (Geothermal Energy Inst.),
R.J. Hanold (1-ANL), N. Keller (Wood & Assocs.), Z.
Krieger (Ormat), K . Kuriyama (Mitsubishi Heavy Industries America), R.G. Lacy (SDG&E), W. MacKenzie
(Munson Geothermal), T. Meidav (Trans-Pacific Geothermal) and R.S. Skryness (Stone & Webster Engineering). The following S. M. U . personnel provided important
services: J . Feeley (art work), I-: Gilbert (typing), E.
Moreau (typing), and M. Pereira (photography). [I]
REFERENCES
A n d e r s o n , I > . N . , H.C. McCabc a n d Magma l’ouer C o m p a n y . Gcwrhrriiiol Kc~.\oi~rc~r.s
Cotrnc.il B l ~ l ~ l . E T l i VI S, , no. 6, 1986, p. 3-5.
Heredjick. N .. l i . N. G e o t her mal I nit iat ive, Pro(.. 11.S.11.0.E. Grorltcri i i u / Pro,qrui?i K f v i e i t . c’. W a s h i n g t o n . 19x7, t o be publi\tied.
Hrtice, A.W. 13.perience G e n e r a t i n g G e o t h e r m a l Pouer a t T h e G c y \ e r \
I’oucr l’lant. S o n o r n a C o u n t y , Califot-ilia. /‘roc. l ’ . , V . C ‘ o i i f . o i i
,%‘OLl’.s(Jllrc(’,\ O / Ellc’l:<rl’,3, 964. p. 284-296,
Hurgassi. P,I).. Historical O u t l i n e of G e o t h e r m a l Technology it) the
I.arderello Region. C ~ c ~ o t l ~ i ~ rRi,.\oirrc,e,.s
i~iul
Cotiiic+l Bl’l.I.ET1.V.
16. no. 3. 1987, p. 3-18.
C a r d u e l l . D . S . I . . 7irrr?iii,q Poirirs iii U i ~ s r c ~ r r 7i.c~hntdog.i..
i
Neale
Watson Acad. Publ., Inc., N e w York. 1972. Ch. 3.
Ctilwr, G . I’crformarice E u l u a t i o n 01 the Ormat Generator at
W a b u s k a . N e v a d a . /’roc. Ti’ii//i A i i i i t r u / G‘c~orhc~riiiul
C o i l / : uiid
M / ~ ~ X . ~ / i Eo Pp K
. I A P - 5 0 5 9 - S R . Palo Alto. C A 1987, p. 4.3-4.1 1.
Dil’ipo, I<. T h e G e o t h e r m a l Po\rer Statiori at A h u a c h a p a n . El Sal\;idol-. G W / / I ~ , ~ l<iiiJJ-sqi,
J ~ I U / . V u , q o ~ i i ~ 6c .~ no.
.
I O , 1978, p. 11-22,
Dil’ippo, K . ~ ; c ~ O / h 1 2 ~ i J Eiic~r,qi.u.\
iU/
(I Sotrr.c.c,of E/c~c.rri(.iri~,
U.S. I k p t .
01 Energy. 1) O E K A 28320-1. U.S. Gnv. Printing Office. Washi ngt o 11. I9 X O .
I>iI’ippo> R . (;eottierniai I:net-gy I>eveiopmerit\ i n Central America.
~;cwrhl~rrilulKc3olrrc.c~.\ ~ ’ O ~ ~ B
l IO~’ ~l . iI .l E ~ ’ l ~
IS,
~ , 110. IO. 1986. p.
3-14.
I) i Pip po K . K a k k o n d a S 11 i 7 i t k LIis h i C o m b i n e d Gcot he r m a I P o w e r
a n d Heating P l a n t . G ‘ c ~ o / l i c ~ r i ~ iHu o
/ / I-irie. 17. 1987. t o be
published.
1)il’ippo. R . a n d Marcell. D F . Fset-g! Analy\i\ of<;eothermal I’oaer
Plants. Gcwrhc,ri,iul Rc,.\oirrc~c,.\Cotriic.i/ 7 K A . V S AC‘7’101’S. 8 ,
1984, p. 47-52.
Dutcher. .).I.. a n d M o i r . I...). Geothermal S t e a m Pricing a t I he <icy\e rs. I.a k c ii nd S o 11o m a Co ~i ti tics. Ca 1i to r n ie , pro^.. / I / li Iiirc,r.\ 01..
EIlc’r,ql. ( ‘ f ) l l l ~ ,O l g i r l . c 0 1 7 / : , I , 1976. p. 786-789.
I..nte N a i . per I.’Encrgia Elett. Lurclrrc~llouiicl ,Moii/c, Ainiuru: El~<,/ric.
1’0i1.1,r h i ’ /~tidr>,qc’iiot~.\
. ~ / l ~ l l l J ENEI.,
l,
KotIIe. 1970.
Featherstone. .1.1.. a n d Powell. D . K . S t a h i l i / a t i o n of Highly Saline
<;eotIicrnial Hrincs. ./. /‘e,/. 7cc.h..April 1981, p. 727-734.
Hitirictis, 1.C. M a g m a n i a x Power Plant
Success a t East Mc\a.
f ‘ I . 0 1 ’ . f.“i,qh//lA J i I l l l U l ~ ~ f ~ O / / l f ~ l ’ lcOll/:
l l U / U J I d M / O ~ ~ , \ h O { lEl’R
,
1
A1’-36X6. I’alo Alto. C A , 1984. p. 6.21-6.30.
H o d g w n , S.F., ed. I lie V t ~ l c a nP o w e r Platit. G‘c,or/irriiiul Hor l ~ i i i c j ,
1.7. 1985. p. 74-76.
Ke\tin. .I.. Dil’ippo. K. a n d Kliailifa, H . E . Hybrid Geothermal-Fossil
P o w e r Plants, M c ~ , / i Eiigiiz..
.
100, no. 12. 1978, p. 2X-35.
Kleinhas, P.V. a n d I’rideaux. D.I..
Design. S t a r t - U p a n d O p e r a t i o n of
S M U D G E 0 N o . 1, /‘roc.. l98.7 E I ’ K I J I I E Gcwrhc,riiiul Coiif. uiitl
WorXskop, l u n e 1985, t o be published.
~
Figure 19. Geothermal plant sites/prospects in South America
and the Caribbean
Concluding Remarks
In conclusion, geothermal energy has developed as a
reliable source of generating electricity wherever in the
world thermal anomalies are found. There are many types
of energy conversion systems proven for use with low-,
medium- and high-temperature fluids, including ones with
extremely high concentrations of impurities. In many
cases, the performance of geothermal plants far exceeds
industry norms for conventional plants. Geothermal
energy is sure t o continue t o play a n important role in
meeting the generation requirements of many countries,
particularly in a world of uncertain oil prices and supply.
Acknowledgements
T h e a u t h o r wishes t o thank J.C. Rowley(L.ANL)for
the invitation t o prepare and present this paper. The folPage 18
Milora, S.1.. a n d lister. .I. W. G‘e~otlic~ri~iul
Eriergj UI u Soirrc.r, I!/
/I.;<, /’oit,w, T h e M I T Press, C a m b r i d g e , M A , 1976.
M o r i , H.. Electrical U p d a t e of.lapan. 1985 lrir ‘1. S i . i ? i p . o i i GlY>t/i~v’iJiU/
Eiicvqi.. I r i r ‘1. C’ol.. C. S t o n e . e d . . Geothcrmal Resources Council.
I h v i s , C‘A. 19x5. p. 107-1 I I .
Geothermal Resources Council BULLETIN M a y 1988
Mou. W.F.. W h i t e m i r \ e r . 0.1). a n d Y a m a w k i , K . N . I h
I1 nitcd Nations. Pro<,. 11. N. Con/: 0 1 1 Not. Sources of' Etirrayr.:Solar
tzrrg I,. Wind Poa,rr uti(/ G ~ ~ / / i e r t n
Ener,q.r,
(~/
vols. 2 a n d 3 .
eotherrnal Energy, R o m e , 1961. ( P u b l . in 1964).
TK.4 VS,4 ('77O.V.S. 6 . 19x2. p. 373-376.
S o l o m o n . S . G . a n d Herning
1.. Heber Binary Project
S t a t u s of
f'lant O p c r a t i o n s a n d Testing, Pro(,. E,nrh Arinuul G r o / h r r m u /
C ' o t i . und Workshop.Et'RI AP-5059-SR, Palo Alto. C A 19x7, p.
4.3-4.I I
~
I h a i n . I . A . a n d Stacey. R . E . Wuirukri ticwthrrrnul Power S t u r i o ~ 25
Y?ur.\ ' Olperurioti, Electricity Div.. M i n . of Energy, Wellington,
Neu. Zealand, 1984.
~
~ ~ o l c 1 1 t i n oB.S.
.
a n d Huning, H.C. T h e Philippines G e o t h e r m a l
Potential a n d Its Development: An Update, 198.5 I n / 7 . Si.ti?p,on
G r o r k e r m u l Dier,qi.. I r i / 7 . Vol.. C . S t o n e , c d . , G e o t h e r m a l
Resource, Council, Datis, C A 1985, p. 157-163.
Geothermal Resources Council BULLETIN M a y 1988
United Nations. Proc. U . N . LYI,tiip. o t i D u s . ant/ U//iiz. ~ / G c o ~ / I c ~ I ~ I u /
Rr.sourc~e.s.Pisa, 1970; Grothc~rtnic~.~.
Sprc.. I.ssue 2. ~ 0 1 s . I a n d 2 .
Pergamon Press, New York, 1970.
on(/ I / . A'. .YI,tvp. on Iki..und L'.sc. of' tiron Francisco, 1975 (Publ. in 1976).
Williams. R . D . Pacific Gas a n d Electric C o m p a n y G e o t h e r m a l O p e r a t i o n \ at T h e Geysers
19x6 Performance Perspective, Proroc,. 7i~11ih
Annual GcwthcJrt?iu/Cor!/: uti(/ Workshop.E P R I A P-5-59-SR.
Palo Alto. C A . 19x7. p. 5.57-5.71.
Page 19