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| Illustration - Makalah Serba Ada |
Renewable Energy Resources is a numerate and quantitative text covering subjects of proven technical and economic importance worldwide. Energy supplies from renewables (such as solar, thermal, photovoltaic, wind, hydro, biofuels, wave, tidal, ocean and geothermal sources) are essential components of every nation’s energy strategy, not least because of concerns for the environment and for sustainability. In the years between the first and this second edition, renewable energy has come of age: it makes good sense, good government and good business.
This second edition maintains the book’s basis on fundamentals, whilst including experience gained from the rapid growth of renewable energy technologies as secure national resources and for climate change mitigation, more extensively illustrated with case studies and worked problems. The presentation has been improved throughout, along with a new chapter on economics and institutional factors. Each chapter begins with fundamental theory from a scientific perspective, then considers applied engineering examples and developments, and includes a set of problems and solutions and a bibliography of printed and web-based material for further study. Common symbols and cross referencing apply throughout, essential data are tabulated in appendices. Sections on social and environmental aspects have been added to each technology chapter.
Renewable Energy Resources supports multi-disciplinary master degrees in science and engineering, and specialist modules in first degrees. Practising scientists and engineers who have not had a comprehensive training in renewable energy will find this book a useful introductory text and a reference book. John Twidell has considerable experience in renewable energy as an academic pro- fessor, a board member of wind and solar professional associations, a journal editor and contractor with the European Commission. As well as holding posts in the UK, he has worked in Sudan and Fiji.
Tony Weir is a policy adviser to the Australian government, specialising in the interface between technology and policy, covering subjects such as energy supplland demand, climate change and innovation in business. He was formerly Senior Energy Officer at the South Pacific Forum Secretariat in Fiji, and has lectured and researched in physics and policy studies at universities of the UK, Australia and the Pacific.
Renewable energy
Renewable energy obtains energy from energy flows that come from “sustainable natural processes”, such as sunlight, wind, flowing water, biological processes, and geothermal. The concept of renewable energy was introduced in the 1970s as part of an attempt to move beyond the development of nuclear and fossil fuels. The most common definition is an energy source that can be rapidly replenished by nature, a sustainable process. Under this definition, nuclear and fossil fuels are excluded.
All renewable energies are by definition also sustainable energy, which means they are available for a long time which makes planning when they run out is not necessary. Although nuclear power is not renewable energy, nuclear support can be sustainable by using breeder reactors using uranium-238 or thorium or both. On the other hand, many opponents of nuclear use the term sustainable energy as a synonym for renewable energy, and therefore do not include nuclear in sustainable energy.
Modern renewable energy sources
Geothermal energy
Geothermal energy comes from radioactive decomposition at the center of the Earth, which heats the Earth from within, and from the sun, which heats the Earth's surface.
solar energy
Because most of the renewable energy is the center of "solar energy" which is meant is energy that is collected directly from sunlight.
Wind energy
Because the sun heats the earth's surface unevenly, wind is formed. The kinetic energy from the wind can be used to run wind turbines, some capable of producing 5 MW of power.
Hydropower
Water energy can be used in the form of motion or temperature differences. Because water is thousands of times heavier than air, even the slowest flow of water can produce a large amount of energy.
Biomass
Biofuels are fuels obtained from biomass – organisms or products of their metabolism, such as dung from cows. He is renewable energy. Usually, biofuels are burned to release the chemical energy stored in them.
