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 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 ...
Since the 1980s, no large-capacity solar distillation plants have been built, mainly for the following reasons: Large installation areas are needed, solar distillation plants have low efficiencies, and solar water desalination has been developed, which in some cases can replace solar distillation (e.g., for medium-size communities). (more…)
Solar distillation is the process in which solar heat is used to purify water from an impure water source by evaporation and conden ...
Solar energy desalination is a method by which the sun’s energy is used to desalinate brackish or seawater to produce fresh drinkab ...
Solar dryers are special structures that enhance the drying power of the sun and protect the agricultural product from dust, dirt, ...
Solar water heating for swimming pool rank as the most successful but least heralded commercial solar application. The use of solar ...
Several passive heating systems, if provided with proper ventilation, can ensure to provide cooling. Passive heating and cooling fo ...
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 ...
The idea of using an absorption fluid as a refrigerant carrier derived from the drawback of VCR (vapor–compression refrigeration) systems that the gas compression requires a high work input. A pump that requires practically no work to increase the pressure in the refrigeration system replaces the complicated and work-consuming compressor. There are two major advantages of absorption refrigeration systems (ARSs) compared with VCRs (vapor–compression refrigeration): No CFCs or HCFCs are used as refrigerants, and they use heat from different sources, such as combustion, industrial processes, waste heat (an economical solution for recovery), or solar heat. (more…)
Heat-actuated heat pumps are cooling systems requiring no electricity for operation. Rather, a heat source is used, avoiding the ne ...
The term cryogenics derives from the Greek kryos, for icy cold. The upper limit that characterizes the cryogenic region of the temp ...
Separation is a unit operation used in absorption heat pumps and chemical processing applications such as solvent extraction and pr ...
Active solar hot water systems water are usable with air, liquid, vapor or liquid collector fluid or gas to liquid process. Hot ...
Micro technology can be employed to produce miniaturized refrigeration and cryocooling systems. Although process intensificat ...
There are literally thousands of uses for lasers. One of the largest applications is telecommunications—sending a signal through fiber optic cables, for example. This application grew rapidly in the 1990s with the phenomenal increase in traffic on the Internet. Optical data storage, such as on compact disks, CD-ROMs, and DVDs, is another important use for lasers. The information age was obviously a boon to this application, and as researchers obtained smaller wavelengths with diode lasers, they were able to fit more information on smaller storage devices. (more…)
Different lasers use different materials as the active medium. The medium can be either solid, liquid, or gas, and there are ad ...
The word “laser” is an acronym for “light amplification by the stimulated emission of radiation.” Lasers of all kinds consist o ...
The first known laser was made by Theodore Maiman at Hughes Research Laboratories in Malibu, California, in 1960, but the seeds ...
Several molecular systems have been constructed that mimic various aspects of photosynthesis. Two of these utilize molecular system ...
It is known that laser printers print faster, but swallow a large amount of energy, even if the printer is in the energy saving ...
More than 48% of the raw material fiber used for paper production (chemical pulp or mechanical pulp) in the United States in 2002 was recovered or reclaimed, with recovered paper contributing 37.7% and wood residues 10.6%. The total has been more or less constant, with the percentage of recovered paper increasing and that of wood residues declining recently due to their increased use in oriented strand board and composite panels. Primary fibers are a renewable, domestic resource, much of which is currently supplied by tree plantations. Short-rotation forestry can be used to further increase the productivity of these plantations. (more…)
Most discussions of energy use in paper production and papermaking are confusing because of a failure to define exactly what is mea ...
Agricultural and forestry residues provide the largest proportion of biomass used for the production of biomas bioenergy. Some esti ...
The evidence on the environmental Kuznets curve indicates that national environmental policies differ between high-income and low-i ...
Another large source of renewable carbon supplies is waste biomass. It consists of a wide range of materials and includes munic ...
Another large source of renewable carbon supplies is waste biomass. It consists of a wide range of materials and includes munic ...
You must perform some sort of tour and visit of your home and property to find out exactly where it may need in applying insulation. A good rule of thumb is that most heated area or perhaps cooled places needs to be split up from unconditioned places using insulation materials. Regardless of your properties design, you can use this rule to ascertain exactly where insulation installation should be set up. Every location will have its consideration in terms of insulation simplicity and cost-effectiveness and may be examined on the basis of both. (more…)
If your house has no attic (most flat-roof houses don’t), chances are there’s a cockloft, a space between roof and ceiling, at ...
Imprinted on every batt or blanket of insulation or on every bag of loose insulation is its R-Value. The higher Insulation R-Value, ...
You know where to insulate, but there’s still one more thing you need to know about—vapor barriers. Well-insulated attics, craw ...
Using blankets the width of your wall studs, insert the blanket between the studs and staple to the studs. (The job is easier i ...
It is easier and less costly to fit insulation in a new home than to retrofit. However, many existing houses have little or no insu ...
There are many efforts to make building more comfortable and to reduce the carbon dioxide emissions from buildings. For many years we tried to increase wall thickness of the wall insulation and roof insulation and adding the bottom insulation.
This seems logical, but I recently attended a seminar in where a speaker tried to make a comparison of as opposed to two major areas of new construction. These building were build year apart and built insulation levels in the store later far exceeded the first branch. Although the shops were of similar size, has a similar level of glass and skylights, the shop recently built, although it improved R-values (please refer to insulation R-Value chart), 43% costs warmer than the last. (more…)
It is easier and less costly to fit insulation in a new home than to retrofit. However, many existing houses have little or no insu ...
Imprinted on every batt or blanket of insulation or on every bag of loose insulation is its R-Value. The higher Insulation R-Value, ...
You must perform some sort of tour and visit of your home and property to find out exactly where it may need in applying insulation ...
If your house has no attic (most flat-roof houses don’t), chances are there’s a cockloft, a space between roof and ceiling, at ...
You know where to insulate, but there’s still one more thing you need to know about—vapor barriers. Well-insulated attics, craw ...