Green Energy

Green technology is not something new, as windmills were first used over one thousand years ago to grind grain in Persia. In recent years green energy has regained political prominence due to world fears that nonrenewable sources of energy such as the classic fossil fuels (oil, gas and coal) may soon run out. The environmental impact of fossil fuels is also an important matter for concern as global warming is thought to be caused by the release of ‘greenhouse gases' into the atmosphere as these fuels are burned. The main forms of renewable energy are solar, wind, geothermal and hydroelectric.

Solar power involves using the energy from the sun and converting solar radiation into electricity by using a photovoltaic (PV) cell, which is a wafer-thin semiconductor. Solar power has great potential since for all intents and purposes the sun will never run out. Indeed if it did then human civilization on earth would also perish. The earth receives more energy from the sun in a year than it would be possible to produce by utilizing all non-renewable energy sources.

Solar power has many different potential applications. For example, it can be used to generate electricity by using mirrors to focus the sun's rays on a small area which heats a fluid that in turn operates a turbine. Electricity can also be generated using photovoltaic cells, in a similar way to how a solar-powered battery works. Solar power is becoming more popular for domestic use, especially in countries closer to the equator that have more access to sunlight. A lot of homes have photovoltaic cells fitted to their roofs to heat up water.

Another form of renewable energy is hydroelectricity. This is produced when the power of gravity from either falling or flowing water is harvested to generate electricity. The most common form of hydroelectricity is obtained by the building of dams. Examples of such dams are the Hoover Dam in the United States of America, which was constructed in the 1930s, and the Three Gorges Dam in China which was opened in 2008. Hydroelectricity can be generated in several ways. For instance, in conventional dams water can be used to push a water turbine and hence generate electricity. Hydroelectricity is relatively cheap once the dams are created but it can have environmental side effects such as land being flooded due to the need to create a body of water to ensure a constant water supply through the turbines. Hydroelectricity can also be generated from the power of the tides. It uses the kinetic energy of the water, moving up and down in waves and currents, to make electricity.

Wind power is slowly becoming used more as it becomes more cost effective per unit of electricity produced compared to other renewable sources. Wind power is generated by placing wind turbines on hills or other exposed elevated areas where the wind can turn the blades of the turbine to generate electricity. One of the main drawbacks of this method is the turbines themselves. Simply stated, they are an eye-sore and can create a visual blight on the landscape. The best areas for wind farms can be hills in areas of outstanding natural beauty. Environmental groups frequently protest the placement of wind turbines on sites where they think the natural landscape would be ruined by their presence. There is also a fear that birds would fly between the blades causing them injury or death.

Another important form of renewable energy is geothermal energy. Heat from the earth's core is used to heat water that is used to power a dynamo and generate electricity, similar to a more traditional power plant. The largest geothermal power plants currently in production are in the United States, Indonesia and the Philippines. Energy from hydrothermal plants can also be produced by pumping high pressure hot water into lower pressure tanks with the resulting ‘flashed steam' being used to produce electricity. More recently hot water from within the earth is being used to heat a secondary liquid which boils at a lower temperature and this is used instead to power the turbine. This method is currently the most popular way of generating geothermal electricity.

Selected full-text books and articles on this topic

Energy: Perspectives, Problems, and Prospects
Michael B. McElroy.
Oxford University Press, 2010
Librarian’s tip: Chap. 8 "Energy from Water and Wind," Chap. 17 "Vision for a Low-Carbon Energy Future"
What Will Work: Fighting Climate Change with Renewable Energy, Not Nuclear Power
Kristin Shrader-Frechette.
Oxford University Press, 2011
Environmental Law and Fossil Fuels: Barriers to Renewable Energy
Outka, Uma.
Vanderbilt Law Review, Vol. 65, No. 6, November 2012
Winds of Change: The Environmental Movement and the Global Development of the Wind Energy Industry
Ion Bogdan Vasi.
Oxford University Press, 2011
Solar Energy: Principles and Possibilities
Rhodes, Christopher J.
Science Progress, Vol. 93, No. 1, Spring 2010
Temporarily FREE! Green Illusions: The Dirty Secrets of Clean Energy and the Future of Environmentalism
Ozzie Zehner.
University of Nebraska Press, 2012
Emerald Cities: Urban Sustainability and Economic Development
Joan Fitzgerald.
Oxford University Press, 2010
Librarian’s tip: Chap. 3 "Renewable Cities"
Global Energy Shifts: Fostering Sustainability in a Turbulent Age
Bruce Podobnik.
Temple University Press, 2006
Energy, Society & Environment: Technology for a Sustainable Future
David Elliott.
Routledge, 2003 (2nd edition)
Librarian’s tip: Chap. 7 "Renewable Energy"
Global Issues for Global Citizens: An Introduction to Key Development Challenges
Vinay Bhargava.
World Bank, 2006
Librarian’s tip: Chap. 13 "Toward a Sustainable Energy Future"
Enhancing the Investor Appeal of Renewable Energy
Mormann, Felix.
Environmental Law, Vol. 42, No. 3, Summer 2012
Investing in a Sustainable World: Why Green Is the New Color of Money on Wall Street
Matthew J. Kiernan.
AMACOM, 2009
Librarian’s tip: Chap. 7 "Sustainability and Competitive Advantage: The New Corporate Imperative - and Some Success Stories"
Learning from the Global Financial Crisis: Creatively, Reliably, and Sustainably
Paul Shrivastava; Matt Statler.
Stanford Business Books, 2012
Librarian’s tip: Chap. 13 "Green Financing After the Global Financial Crisis"
Management of Renewable Energy and Regional Development: European Experiences and Steps Forward
Zamfir, Andreea Ileana.
Theoretical and Empirical Researches in Urban Management, Vol. 6, No. 3, August 2011
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