RENEWABLE ENERGY SOURCES

Renewable Energy Sources

Renewable Energy Sources

Introduction

The exploitation of the renewable energy sources including solar, wind and hydro is very old. For many centuries before our era, these were used throughout history until the arrival of “Industrial Revolution”. In recent years, due to the increased cost of fossil fuels and environmental problems arising from their exploitation, we are witnessing a rebirth of renewables. Renewables are inexhaustible, clean, and can be used on a self, (and that can be leveraged in the same place in which they occur). They also have the added benefit of complementing each other, promoting integration between them. For example, solar photovoltaic electricity provides clear days (usually with little wind, because of the dominance of the anticyclone), while on snowy days, windy, often cloudy, wind turbines are those that can produce more electricity. Most of the developed countries are relying on the efficient use of renewable energy to reduce the utilization of fossil fuels (Doyle, 2005, 44-45).

Renewable resources are often understood being the environmental components—wind, sunlight, water, forests, crops, fisheries, and so on—of complex socio-ecological systems that, if managed properly, can meet human needs for raw materials, energy, and food on a long-term, sustainable basis. Societal interest in renewable resources stems from increased awareness of the problems resulting from reliance on nonrenewable resources (fossil fuels and minerals). Overdependence on these resources contributes greatly to air and water pollution, global climate change, geopolitical conflict, resource wars, economic instability, and other major difficulties that many believe can be addressed only by a global transition to economies that are based on renewable resources. Practically and conceptually, such a transition requires an appreciation of the complex socio-environmen-tal character of resources and renewability. This entry considers this character and explores how issues of scale, unequal resource distribution, and political power influence the potential for renewable resource systems to emerge (Guha, 2008, 71-72).

Solar Energy in Developed Countries

Solar Energy

Solar energy, the energy radiating from the sun, can be harnessed to obtain electrical power or heat. At present, there are three main technologies employed in the exploitation of solar energy: photovoltaic cells, solar thermodynamic systems, and solar thermal systems. Photovoltaic cells exploit the photovoltaic effect; in other words, the property that some materials have to generate electrical power when directly hit by rays of the sun. The photovoltaic cell constitutes the base element of the process transforming solar radiation into electrical power: Assembled cells make a photovoltaic module, which is made up of 36 cells, each of them producing around 40 to 50 watts of power. When a number of modules are assembled as a single structure, it becomes a solar photovoltaic panel (Mallon, 2006, 63-64).

Solar thermodynamic systems instead exploit sunlight to produce electricity from the energy released by heated fluids at a high temperature (about 400 degrees Celsius). This method is the most competitive solar system because it can be put into operation quickly and is the most flexible. At this time, there are three types of solar thermodynamic systems: parabolic dish, parabolic ...