Hydropower Research and Development Focusing in Turbine Efficiency

hydropower efficiency
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…)

Hydraulic Turbines Classification, Types, and Principles

Hydraulic turbines have two main classifications: impulse and reaction. The impulse turbine generally uses the velocity of the water to move the runner and discharges to atmospheric pressure. The water stream hits each bucket on the runner. There is no suction on the down side of the turbine, and the water flows out the bottom of the turbine housing after hitting the runner. An impulse turbine is generally suitable for high-head, low-flow applications. (more…)

Hydropower Plant Cost, Construction, Components And Functions

hydropower cost
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…)

Nuclear Generating Capacity In The United Kingdom

nuclear united kingdom
Following the recent completion of three nuclear power plants, there is now some 9.6 GW of nuclear capacity in the United Kingdom. The nuclear share of electrical output, which has stood at around 13% for many years, should rise to around 20% when this capacity is in full operation. A further two reactors are currently under construction which will increase the British nuclear capacity to more than 12 GW by the late 1980s, which could bring the nuclear share of electrical output to around 25%. (more…)

Photo-Electrochemical Energy Conversion Device

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…)

Artificial Photosynthetic Devices

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…)

Federal Excise Taxes to Motor Fuels: Gasoline, Diesel, Aviation Jet Fuel

Federal Excise Taxes
Federal Excise Taxes placed on specific energy sources tend to reduce energy demand for these energy sources in both the short and the long run. The federal government imposes excise taxes on almost all petroleum products (including petroleum additives) and coal (see Table 1). The federal government also imposes federal excise taxes on many transportation uses of methanol, ethanol, natural gas, and propane and imposes a fee on electricity produced from nuclear power plants and nuclear power electricity. (more…)

Peak Electricity Demand Impact and Reducing Power Needs During Peak Periods

Peak Electricity Demand
Power generation and distribution networks are built with spare capacity to meet peak periods of energy consumption is usually a time when demand for heating and / or cooling is particularly acute accommodate. Normally, peak electricity demand in some cases last just a few hours every year. And while the networks have always had to cope with peaks in recent years, the electricity consumption during peak hours has increased dramatically in the afternoon. (more…)

Solar Water Desalination: Reverse Osmosis, Electrodialysis, and Mechanical Vapor Compression Desalination Methods

Solar energy desalination is a method by which the sun’s energy is used to desalinate brackish or seawater to produce fresh drinkable water. There are two methods for using solar energy: directly by heating and evaporating the brackish or seawater in a solar still (this method is called solar distillation) and indirectly by capturing solar energy using one of the techniques that transform solar radiation into thermal or electrical energy to drive a conventional desalination method (the indirect method is called solar-assisted or solar-driven desalination). (more…)

Solar Drying: Process, Definition and Background

Drying is one of the most important post harvest steps. It enhances the storage life of the crop products, minimizes losses during storage, and saves shipping costs. The drying process is the removal of water from the wet surface of the food. In this process, heat is transferred by convection and radiation to the surface of the produce. This heat raises the temperatures heat and evaporates the moisture from the exterior of the agricultural products, diffusing the interior moisture to the surface and replenishing the evaporated surface moisture. (more…)

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