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02 MARKET AND INDUSTRY TRENDS
GEOTHERMAL POWER AND HEAT
GEOTHERMAL MARKETS
Geothermal resources provide energy in the form of electricity
and direct heating and cooling, totalling an estimated 543 PJ (151
TWh) in 2015. 1 Geothermal direct use and electricity generation
each are estimated to account for one-half of total final geothermal
output (75 TWh each)i. 2 Some geothermal plants produce both
electricity and thermal output for various heat applications.
About 315 MW of new geothermal power generating capacity
was completed in 2015, bringing the global total to an estimated
13.2 GW. 3 Countries that added capacity during the year were (in
order of new capacity brought online) Turkey, the United States,
Mexico, Kenya, Japan and Germany. 4 (p See Figure 10.) Turkey
accounted for about half of new installations.
At the end of 2015, the countries with the largest amounts of
geothermal power generating capacity were the United States
(3.6 GW), the Philippines (1.9 GW), Indonesia (1.4 GW), Mexico
(1.1 GW), New Zealand (1.0 GW), Italy (0.9 GW), Iceland (0.7
GW), Turkey (0.6 GW), Kenya (0.6 GW) and Japan (0.5 GW). 5
(p See Figure 11.)
Capacity additions in 2015 were somewhat lower in total
than in recent years. As many as 11 binary ii power plants were
completed, totalling 129 MW, and another 8 single-flash plants
were completed, totalling 186 MW. 6
Turkey continued its relatively rapid build-up of geothermal
power capacity, with 10 units completed in 2015, adding 159 MW
for a total of at least 624 MW. 7 Among the plants completed was a
4 MW binary Organic Rankine Cycle (ORC) unit by Exergy (Italy)
that is claimed to be the world’s first to operate at two pressure
levels, which increases energy recovery and overall efficiency
from low-temperature resources. 8 Turkey is well on its way to
meeting its goal of having 1 GW of geothermal power capacity
in place by 2023. 9 In 2015, the country generated 3.37 TWh with
geothermal energy, up 50% over 2014. 10
The United States added 71 MW with two binary plants (by
Ormat, United States) coming online in Nevada, bringing total
operating capacity to nearly 3.6 GW (2.5 GW net). 11 Generation
in 2015 was 16.8 TWh, representing a 5.6% increase relative to
2014. 12 There are some indications that significant new growth
could be unleashed if economic and regulatory conditions
improved; about 500 MW of projects are languishing in latestage
development in the United States. 13
Mexico brought online a 53 MW unit at the Los Azufres field in
early 2015 and retired four ageing wellhead units (5 MW each)
in the same location. In addition, two 5 MW wellhead plants
were installed in the Domo San Pedro field, which is Mexico’s
first privately owned geothermal project. 14 The total net increase
for the year was 43 MW, bringing Mexico’s installed capacity
to 1.1 GW. 15 During 2015, Mexico’s energy authorities provided
additional concessions for the government’s power producer
(CFE) in fields where the company already has developed
geothermal resources. However, most of the country’s remaining
geothermal potential was opened for private investment and
development. 16
Kenya added at least 20 MW of new capacity in 2015 for a total
of about 600 MW. 17 Drilling commenced on the first phase of the
Akiira Geothermal 140 MW plant after Kenya Power signed a PPA
for its output. It is expected that the plant will be sub-Saharan
Africa’s first private sector greenfield geothermal development. 18
Exploration risk insurance was secured for this project; in many
cases, however, risk mitigation remains a hurdle for geothermal
development, especially in developing countries. 19
In late 2015, another binary plant was completed in Bavaria in
Germany, supplying 5.5 MW of power generating capability in
addition to 12 MW of thermal output. 20 As of early 2016, Germany
had a concentration of several small geothermal plants around
Munich that take advantage of local low-temperature geothermal
resources to provide both heat and power. 21
Japan also added several facilities (altogether 6.8 MW) in 2015,
bringing its total capacity to 535 MW. The new plants included
i This does not include the renewable final energy output of ground-source heat pumps, which was estimated at 358 PJ (99 TWh) in 2015. See endnote 1 for
this section.
ii In a binary plant, the geothermal fluid heats and vaporises a separate working fluid with a lower boiling point than water, which drives a turbine for power
generation. Each fluid cycle is closed, and the geothermal fluid is re-injected into the heat reservoir. The binary cycle allows an effective and efficient
extraction of heat for power generation from relatively low-temperature geothermal fluids. Organic Rankine Cycle (ORC) binary geothermal plants use an
organic working fluid, and the Kalina cycle uses a non-organic working fluid. In conventional geothermal power plants, geothermal steam is used directly
to drive the turbine, whereas in a conventional thermal power plant, fuelled by nuclear reaction or fossil fuels, the working fluid is pure water.
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