Page 26 - Geothermal Energy Renewable Energy and The Environment

8 Geothermal Energy: Renewable Energy and the Environment

the local and regional circumstances. However, research and development efforts are underway to
develop the means to manage geothermal power facilities to allow a load following and peaking
capability.

GeneraTinG elecTrical power for local use
Electrical power generation as described above is the primary means whereby residential, commer-
cial, and industrial customers obtain electrical power. However, renewable energy resources readily
lend themselves to situations where power generation can be accomplished with modest generators
that supply power to a limited number of customers in a restricted area. Such distributed genera-
tion capabilities are growing in number. The compact nature of new generation binary geothermal
generators, for example, have the potential to supply a few hundred to a few thousand kilowatts of
power from a single well. Such a facility can supply power to an industrial site, a small community,
or any other type of operation that requires power at that scale without accessing the power grid.
Such facilities require minimal operational oversight and can be cost effective. These systems are
discussed in more detail in Chapter 9.

how ThIs book Is orGanIzed
Geothermal energy is a complex energy source with diverse applications. For that reason, this book
develops the fundamental scientific principles that apply to geothermal energy resources and their
use in Chapter 2 (Earth sciences), Chapter 3 (thermodynamics), Chapter 4 (hydrology), and Chapter 5
(geochemistry). Using the principles developed in those chapters, the topics of exploring for resources
(Chapter 6), assessing their properties and magnitude (Chapter 7), and drilling for the resource
(Chapter 8) are then discussed. The properties, characteristics, and operational fundamentals are
considered for each of the applications that employee geothermal energy in Chapter 9 (power gener-
ation), Chapter 10 (ground source heat pumps), and Chapter 11 (direct use applications). Chapters 12
and 13 present the environmental and economic issues, respectively, associated with geothermal
applications. Chapter 14 discusses possible future developments that can significantly affect the role
of geothermal energy in the overall energy landscape.
Within each chapter, certain conventions are followed in the presentation of material. The first
time a word or phrase is used that contains important conceptual material and will appear repeat-
edly in the future is italicized. To assure that the material is presented with sufficient rigor that
the basic concepts and principles are precisely accurate, mathematical descriptions are used when
appropriate. It is assumed that the reader has a basic command of algebra, trigonometry, and calcu-
lus. Finally, resources that contain important information are referenced in the body of the material
in each chapter. When appropriate, Web sites are included. There is also, at the end of each chapter,
an annotated list of a few key information sources that can provide useful information beyond that
contained in the body of the chapter.

synopsIs

Growth in the human population and energy use, as well as the consequent environmental impacts
have lead to interest in finding new energy resources that are renewable and have reduced greenhouse
gas emissions. Geothermal energy is a versatile resource that can be used in many situations to meet
these goals. It requires no fuel supply and related infrastructure and can be deployed in a variety of
settings. Geothermal energy can be used to provide heat for heating, ventilating and air conditioning
(HVAC) or other purposes, as well as for power generation. It has the potential to play an important
role in the transition from fossil fuels to energy sources that have minor environmental impacts.
Successful deployment of renewable energy resources, however, requires that the resource be care-
fully matched to the application being developed.