Up to around 1980, hydropower research and development (R&D) efforts focused mainly on improving turbine efficiency, reducing cavitations, and increasing generation. Whereas older units had efficiency ratings as low as 60%, the new units have efficiency ratings of approximately 90%. The U.S. Department of Energy (DOE) also looked at new technologies for developing low-head, ultra low-head, and small hydropower projects. These technologies included the following: (more…)
Hydropower, also known as hydroelectric power, is the use of water to produce power. Harnessing water to perform work has been ...
The World Commission on Dams (WCD) was formed in 1998 by a joint initiative of the World Conservation Union (IUCN) and the Worl ...
The winners in hydropower and other large dam projects are those who gain electricity, domestic water supplies, sanitation, dro ...
The water levels of most of the world’s rivers fluctuate with seasonal rains, melting snows, or droughts, and in the arid zones ...
Hydraulic turbines have two main classifications: impulse and reaction. The impulse turbine generally uses the velocity of the wate ...
Hydropower, also known as hydroelectric power, is the use of water to produce power. Harnessing water to perform work has been going on for thousands of years. The Greeks used waterwheels for grinding wheat into flour more than 2000 years ago. Besides grinding flour, the power of the water was used to saw wood and to power textile mills and manufacturing plants. This article looks briefly at how hydropower plant began, why it is considered renewable energy technology, the parts of a hydropower plant, types of turbines and when they are used, and what research and development is occurring. (more…)
Up to around 1980, hydropower research and development (R&D) efforts focused mainly on improving turbine efficiency, reducing c ...
The water levels of most of the world’s rivers fluctuate with seasonal rains, melting snows, or droughts, and in the arid zones ...
The World Commission on Dams (WCD) was formed in 1998 by a joint initiative of the World Conservation Union (IUCN) and the Worl ...
The winners in hydropower and other large dam projects are those who gain electricity, domestic water supplies, sanitation, dro ...
The demand for electric energy by a community varies with the time of day and with the time of year. An electric power utility ...
The winners in hydropower and other large dam projects are those who gain electricity, domestic water supplies, sanitation, drought relief, sustainable irrigation, flood control, improved water transport, industrial and employment opportunities, food security, better roads, telecommunications, and other benefits. As well, other economic multipliers may arise and whole regions may flourish. This is an impressive list and is the very basis of modernization and liberation from the drudgery of traditional low technology rural life. Electricity, radio, and domestic water supplies completely transform the lives of those who gain these goods, and better health and education are the most obvious outcomes. (more…)
The water levels of most of the world’s rivers fluctuate with seasonal rains, melting snows, or droughts, and in the arid zones ...
Up to around 1980, hydropower research and development (R&D) efforts focused mainly on improving turbine efficiency, reducing c ...
The World Commission on Dams (WCD) was formed in 1998 by a joint initiative of the World Conservation Union (IUCN) and the Worl ...
Hydropower, also known as hydroelectric power, is the use of water to produce power. Harnessing water to perform work has been ...
The first step in categorizing potential benefits and costs is determining the relevant scope of the analysis. We have concluded th ...
The water levels of most of the world’s rivers fluctuate with seasonal rains, melting snows, or droughts, and in the arid zones there are flash floods. It makes sense to capture and store the abundant waters and later release it during the low flow periods or use it for power. So dams have been built for the purposes of irrigation, municipal water supply, and hydroelectricity generation. Flood control and transportation benefits are also important. Cities are growing all over the developing world, and they require water supplies and reservoirs. Since the beginning of the 20th century, hydropower energy has steadily increased and it now supplies 19% of worldwide electricity. (more…)
Hydropower, also known as hydroelectric power, is the use of water to produce power. Harnessing water to perform work has been ...
The winners in hydropower and other large dam projects are those who gain electricity, domestic water supplies, sanitation, dro ...
The World Commission on Dams (WCD) was formed in 1998 by a joint initiative of the World Conservation Union (IUCN) and the Worl ...
Up to around 1980, hydropower research and development (R&D) efforts focused mainly on improving turbine efficiency, reducing c ...
Water power sources is an interesting source of energy. It is available freely in nature. The constant flow of water can guaran ...
The World Commission on Dams (WCD) was formed in 1998 by a joint initiative of the World Conservation Union (IUCN) and the World Bank (WB) after a historic meeting of leading dam proponents and opponents in Switzerland, with proceedings reported by Dorcey and others. The WCD was asked to discover the truth about the hydropower energy facts, hydropower energy pros and cons, cost, effect, and benefit of large dams and it functioned independently for 2 years at a cost of $10 million. The money was well spent, and at the end of that period the WCD produced a comprehensive report and numerous support documents, and then dissolved itself. The report and support documents remain on the Internet available to all, and they have changed forever the debate about dams. (more…)
The water levels of most of the world’s rivers fluctuate with seasonal rains, melting snows, or droughts, and in the arid zones ...
Hydropower, also known as hydroelectric power, is the use of water to produce power. Harnessing water to perform work has been ...
The winners in hydropower and other large dam projects are those who gain electricity, domestic water supplies, sanitation, dro ...
Up to around 1980, hydropower research and development (R&D) efforts focused mainly on improving turbine efficiency, reducing c ...
Some of alternative fuel sources are by no means new. For centuries people have harnessed the power of running water for a vari ...
Transportation is another sector that has increased its relative share of primary energy use. This sector has serious concerns as it is a significant source of CO2 emissions and other airborne pollutants, and it is almost totally based on oil as its energy source. An important aspect of future changes in transportation depends on what happens to the available oil resources, production and prices. At present, 95% of all energy for transportation comes from oil. (more…)
Under both former President Bush and new President Obama, the U.S. government has vowed to reduce reliance on imported oil. The ...
Global energy consumption in the last half century has increased very rapidly and is expected to continue to grow over the next ...
From prehistory until the Industrial Revolution, most energy sources used by humans were localized (i.e., available within 5–10 mil ...
Do we have the resources? Rudolf Diesel developed the diesel engine which ran on biodiesel vegetable oil in the late 1800s. At the ...
One study that does address the peak-oil scenario directly is a 2005 report conducted for the National Energy Technology Labora ...
The basic processes that occur in such a system are well understood. The semiconductor electrode efficiently absorbs light, producing an excited electronic state. In this excited state, the electron and the electron vacancy (the ‘‘hole’’) are both more energetic than they were in their respective ground states. The photo-excited electrons and holes are generally not tightly bound to an individual atom or set of atoms in the solid. (more…)
Several molecular systems have been constructed that mimic various aspects of photosynthesis. Two of these utilize molecular system ...
Today, photovoltaic cells only contribute a small proportion (approximately 0.04 percent) of total electricity in the United St ...
Certain materials, generally metal oxides, can sustain the unassisted photo-electrolysis of water into H2 and O2. The energy co ...
The fuel cell can trace its roots back to the 1800s when a Welsh-born, Oxford-educated barrister, Sir William Robert Grove, realize ...
A fuel cell is an electrochemical device that combines hydrogen with oxygen to generate electricity, heat and water to produce. ...
Several molecular systems have been constructed that mimic various aspects of photosynthesis. Two of these utilize molecular systems that are derived from natural photosynthesis but that incorporate chemically based modifications to produce artificial photosynthetic devices. These devices use artificial photosynthetic pigments to drive chemical reactions across lipid bilayers or use noble metal catalysts to change the function of the photosynthetic process to produce hydrogen and oxygen instead of sugars ethanol and oxygen. Neither of these systems are sufficiently robust to be operated for extended periods of time as energy unit conversion devices, but they have shown that it is possible to produce artificial photosynthetic assemblies that function well in a laboratory setting. (more…)
The basic processes that occur in such a system are well understood. The semiconductor electrode efficiently absorbs light, produci ...
Certain materials, generally metal oxides, can sustain the unassisted photo-electrolysis of water into H2 and O2. The energy co ...
A fuel cell is an electrochemical device that combines hydrogen with oxygen to generate electricity, heat and water to produce. ...
A fuel cell is an electrochemical device that directly converts a fuel to electricity by means of reactions on the surfaces of ...
The fuel cell can trace its roots back to the 1800s when a Welsh-born, Oxford-educated barrister, Sir William Robert Grove, realize ...
Renewable energy generators are devices that convert energy from its original form in the renewable energy source into electricity. Renewable energy generators that are most likely to be found in hybrid energy systems include wind turbines and photovoltaic panels. Some hybrid energy systems use hydroelectric generators, biomass fueled generators, or fuel cells. It should be noted that many renewable energy generators include rotating electrical machines acting in the generating mode, which is also called a generator. It should be clear from the context what is meant. (more…)
In many countries of the world wind power expands and covers a steadily increasing part of these countries’ power demand. Growi ...
Wind energy alongside solar energy is one form of renewable energy and its supply is abundant in earth. Most people distinguish ...
In 2001, there were 14,000 small wind turbines for home/domestic use in the United States. The market potential for national an ...
Would it not be great to be able to produce your own electricity supply at home? The idea of being independently powered up without ...
Wind is a natural and inexhaustible source of energy, wind does not have to be imported or mined from deep down the earth. Wind ...
The term cryogenics derives from the Greek kryos, for icy cold. The upper limit that characterizes the cryogenic region of the temperature scale is subjective. If the delimitation criterion takes into consideration practical reasons, then this upper limit can be established at a higher than usually declared value (120 K) in order to include natural gas fuel liquefaction. The cryogenics region of the temperature scale 0–120 K can be divided into sub regions according to the criteria of the cryogenic method and refrigerant (known as crycoolers) as follows: (more…)
The idea of using an absorption fluid as a refrigerant carrier derived from the drawback of VCR (vapor–compression refrigeration) s ...
Micro technology can be employed to produce miniaturized refrigeration and cryocooling systems. Although process intensificat ...
The issues of hydrogen storage run through the hydrogen production, hydrogen transport, supply and demand for end use of hydrog ...
n fabricating microscale energy systems, a number of operating conditions must first be taken into account. Foremost are the op ...
Many small-scale energy systems require effective miniaturized pumps and expanders. These devices are responsible for conveying ...