Constance University of Applied Sciences

Economic and Social Sciences

Business Administration

Environmental Economics

BW 7

Ludmilla Deines

ESSAY

RENEWABLE ENERGIES -

GEOTHERMAL ENERGY

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RENEWABLE ENERGIES ­ GEOTHERMAL ENERGY

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Ludmilla Deines

Content

1. Challenge and Objectives of this Essay 3

2. Renewable Energies 6

2.1

Status and Perspectives 6

2.2

Global Potential of Renewable Energies 10

2.2.1

Solar Energy 10

2.2.2

Biomass 12

2.2.3

Wind Energy 12

2.2.4

Hydropower 13

3. Geothermal Energy 13

3.1

History 14

3.2

The Nature of Geothermal Resources 15

3.3

Technologies 17

3.4

Potential and Utilization of Geothermal Energy 20

4. Summary and Conclusion 22

5. Appendix ­ Energy Units 25

6. Bibliography 26

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1. Challenge and Objectives of this Essay

Nowadays, it is unimaginable for people, at least in industrialized countries, not to have any

access to energy sources. For the industry sector it is the basic precondition for its existence.

For every little step within the production process, being the production of a good itself, the

handling with raw materials or the transportation of the final product to the customer,

plenty of energy is required. Private households also consume a lot of energy. We need

energy for cooking, for washing, for cleaning and heating our homes, for watching television,

for listening to the music, for being able to read a book after the sunset. But due to the

global population growth, the available earth′s resources have come under enormous

pressure to meet the humans′ energy needs (Pérez Latorre, 1999, p. 2). In the last 30 years

the world′s population has grown by more than 30% (www.weltbevoelkerung.de *1+) and

reached the present status of about 6.6 billion people (www.cia.gov [2]). The total energy

consumption has even increased more quickly comparing to the number of people on the

planet. It has just doubled between 1970 and 2000. Within a short time people have

consumed a colossal part of precious natural resources which took millions of years to

produce (BMU, Renewable Energies ­ Innovations for the future, 2006, p. 10). At the same

time the population continues to grow and is estimated to reach about 9.1 billion people by

the year 2050 (www.un.org [3]).

World Population (Billions)

10,00

9,00

8,00

7,00

6,00

5,00

4,00

3,00

2,00

1,00

1950

1960

1970

1980

1990

2000

2010

2020

2030

2040

2050

Year

Figure 1: Development of the world population,
own graph, data based on United Nations, World Population Prospects: The 2006 Revision, 2007,
http://esa.un.org/unpp/

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As the supply of oil, gas, coal and uranium, so called classic energy resources, is quite

limited, the increase of population could result in the energy supply shortfall with

considerable economic and social consequences. But this is not the only problem. The

reserves of fossil fuels are distributed unequally over the globe (BMU, Renewable Energies ­

Innovations for the future, 2006, p. 11). The high dependence of energy-hungry industrial

countries from energy supplying countries can even lead to political conflicts, which already

occurred in resent past.

Furthermore the use of these energy resources has significant environmental effects. The

capacity of the environment to absorb the waste produced by the energy consumption is

strictly limited, too. Moreover, these waste products not only damage the environment, but

also are harmful to the human health (BMU, Renewable Energies ­ Innovations for the

future, 2006, p. 12). For example the mining and enrichment of uranium produces

radioactive isotopes contaminating areas including ground water, air and plants. As a result

the whole ecosystem including humans is affected. There is also a lot of waste produced in

the reactor core, for which there is no known way of a safety disposal. Handling of by-

products of nuclear energy is a big problem. But the danger of underestimating the given risk

of accident which exists in spite of preventive measures should be taken into consideration,

too. Some accidents at nuclear power plants already occurred in the past. The worst nuclear

accident happened in 1986 in Chernobyl, former U.S.S.R. (today Ukraine), as the reactor at

the power plant exploded, causing a great deal of environmental and health problems which

are noticeable till this day (www.wagingpeace.org [4]). Thousands of people including

children died and still suffer from the consequences of radiation. 350,000 citizens had to be

evacuated. The consequences of the accident extended far beyond Ukraine and the year

1986 (BMU, Tschernobyl, Magazin zur Atompolitik, 2006, p. 2).

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Figure 2: Contaminated areas due to the accident at nuclear power plant in Chernobyl
http://www.tagesschau.de/ausland/meldung121596.html

While an accident at a nuclear power plant would scare everyone, damages caused by

accidents in the oil industry don′t shock the public any more, because they occur more often

and even became quite normal. However, the consequences of such accidents may last for

years. For example in 1989 the oil tanker Exxon Valdez struck a riff in Alaska′s Prince William

Sound and precipitated an environmental disaster. 257,000 barrels of oil leaked and polluted

the coast area. Thousands of birds, fish and mammals died. In spite of billions of dollars

spent on the cleanup of the area, today, almost 19 years later, there are still oiled beaches

and moribund animals (www.evostc.state.ak.us [5], www.greenpeace.de [6]).

Apart from the accidents relating to the oil production and the oil transportation, there is

another type of waste produced by the consumption of oil. The effect of carbon dioxide, a

by-product of oil consumption, is considered to be the major factor of causing climate

change.

The challenge of this essay is to analyse, whether and if so which alternative energy sources

are to be considered as an answer to the problems mentioned above. Thereby I want to

examine sustainable energy resources in order to find out, whether their utilization make

sense politically, economically and environmentally. First I will provide general information

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about renewable energies and give an overview of main renewable energy sources. Finally I

will focus on geothermal energy, analysing this energy source more detailed.

2. Renewable Energies

2.1 Status and Perspectives

Renewable energy is a generic term for a wide range of naturally occurring energy sources,

which are able to replenish themselves (European Commission, Renewable Energy Sources ­

Sectoral Report 1995-97, 1998, p. 6). As a result of my analysis I drew a conclusion, it is

beyond question that the use of renewables considerably contributes to the solution of the

problems exemplified above. Their use makes good political and economical sense. Due to

the fact that the renewable energies are endless, they add to the secure energy supply and

help to prevent resource conflicts. Renewable energy resources are in general locally

available and contribute to the independence from the oil supplying countries. Of course

there are also other ways to become independent from the powerful suppliers of fossil

energy. Some economies try to become independent from the oil and gas suppliers by

investing in nuclear energy in their countries. So does for example the government of

Belarus, initiating a construction of a new nuclear power plant, which should operate at full

capacity as from 2020 (Südkurier, 16.01.2008). The problem of dependency may be solved

by this action, but other problems will be created. The effects on the environment and

additional risks for the whole ecosystem of the country and large areas around are grave.

In contrast the use of sustainable energy resources not only reduces the dependency from

fossil energy suppliers, but also makes it possible to limit the production of harmful

pollutants and to contribute to climate protection (BMU, Renewable Energies ­ Innovations

for the future, 2006, p. 20). Though the use of renewable energies is not fully free of

pollutants, it causes by far less damage than the use of fossil energies. Replacing one tonne

of oil equivalent (toe) of primary fossil fuel by renewable energies, the emission of CO2 is

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