How Nuclear Power Works

Posted on January 8, 2012 by Chris West

To know how nuclear power works, it is essential to know the fuels used in the nuclear power plants and the detailed processes or steps involved in the operation.

Generating electricity through nuclear power, as it is the final goal, is an enormously complex technical feat. Combined skills of geologists—scientists who study Earth’s structure, especially rocks—, mine operators, engineers, and scientists, as well as large numbers of highly trained and skilled plant operators are required in that technical task.

How Nuclear Power Works

How Nuclear Power Works – Uranium

Generation of nuclear power begins mostly with the fuel, uranium. Among the naturally occurring elements, uranium is the heaviest. It is used primarily in the nuclear industry. Uranium has sixteen different isotopes, among which the most common ones are U-235 and U-238. Between these two, the more abundant isotope is U-238 which accounts for 99.3 percent of the uranium in the Earth’s crust and plays a role in keeping the Earth warm. Nuclear power can be produced from both U-235 and U-238. To understand the detail how nuclear power works, we can proceed with one isotope, for example, U-235.

How Nuclear Power Works – Energy

The nucleus of a U-235 atom consists of ninety-two protons and 143 neutrons. From this isotope of uranium, atoms can be split relatively easily. If a U-235 atom is struck by a neutron, the atom splits releasing an amount of energy. Two or three neutrons of the Uranium are also released in addition to energy.

The neutrons released from the reaction in turn split other atoms. The same process goes on in the form of a chain reaction. In a nuclear reactor, the released energy from neutron atom is at first kinetic energy which then converted to heat. This heat is then used to produce steam, which turns a generator to produce electricity.

How Nuclear Power Works

How Nuclear Power Works – Nuclear Reactors

To make nuclear power workable, there are several types of nuclear reactors—with different shapes and types—of different technologies to be adopted. Primarily those reactors created at earlier period were huge. They were able to produce the greatest amount of power possible. The recent nuclear reactors are designed such that they could be smaller as well as making them less costly and easier to build. In general, nuclear reactors come in two basic types: pressurized water systems and boiling water systems.

Between the two, the pressurized water reactor system is most common. As it can be guessed from its name, it relies on water under pressure to produce the heat needed to produce electricity. In this system, the water acts as a coolant. Another major system is the boiling water reactor system. In terms of the question how nuclear power works, the pressurized water system is more efficient than the boiling water reactor system.

How Does Wind Energy Work

Posted on January 6, 2012 by Chris West

While discussing about wind energy as an alternative form of energy, a popular issue regarding this subject is how does wind energy work. To address this issue, we need a detail explanation of the wind energy from its production in the environment. Simply speaking, wind energy is the energy coming from wind. To understand how this energy works we should look forward to the fact that how does wind retain this energy within it.

How Does Wind Energy Work - Wind Turbine (click to expand)

How Does Wind Energy Work

Although in everyday discussions of alternative forms of energy, sometimes a distinction is made between wind power and solar power, the distinction is unnecessary at least in one point of view that the wind which powers wind turbines is itself a form of solar power. Simply speaking, wind gets its power within it from the solar power directly or indirectly.

The energy coming from the sun does not strike the Earth evenly. Air around the equator absorbs more energy than the air above the poles. This difference in energy causes air, a fluid much like water, to move in currents. Air, like any other substance, expands when it is warmed and contracts when it is cooled. Warm air, because it is less dense than cool air, is lighter, so it rises.

How Does Wind Energy Work – In Simple Terms

It is like a less-dense piece of wood rises to the top of more-dense water. Cold air, because it shrinks, is denser than surrounding warm air, so it sinks. As warm air rises, colder, heavier air flows in to replace it, causing a current of air—in other words, wind. Wind is also produced from the rotation of the Earth. Earth’s rotation allows winds to circulate in more or less predictable patterns across the Northern Hemisphere and Southern Hemisphere.

Produced in either way, these winds contain huge amounts of kinetic energy—the energy contained in any fluid body in motion. It is found that about two percent of the solar energy that strikes Earth is converted into wind.

How Does Wind Energy Work

To make this wind energy usable in everyday practice some sort of machinery is required. Windmills or wind turbines are such sort of machines.

There are many windmills throughout the whole world in different design and architecture. If placed in a good place, windmill produces electricity and heat using the kinetic energy of wind. This electricity or heat energy then can be used in various everyday needs. So, starting from its production, the wind, how then goes in everyday household needs, is a good answer to address the issue, how does wind energy work.

Definition of Nuclear Energy

Posted on January 4, 2012 by Chris West

The simple definition of nuclear energy speaks about how such energy produced or released from the nucleus of an atom. The nuclear energy actually can be produced in two ways namely fission or fusion. Fission occurs when the atomic nucleus is split apart. On the other hand, fusion is the result of combining two or more light nuclei into one heavier nucleus. Between these two, most often nuclear fission is considered while talking about nuclear power. Power production in the other way, from nuclear fusion, is still in its beginning.

Definition of Nuclear Energy

Atoms of any element are made up of several parts: protons, neutrons, electrons, and a nucleus. Among these parts nucleus, the positively charged part, is the center of the atom. The other parts are particles of an atom, among which protons are positively charge, electrons are negatively charged, and neutrons are uncharged. The negatively charged electrons orbit the nucleus. This basic structure of an atom helps in understanding of the production of nuclear energy.

Definition of Nuclear Energy – Fission

Fission can occur in two ways—first, in some very heavy elements, such as rutherfordium, the nucleus of an atom can split apart into smaller pieces spontaneously. With lighter elements, it is possible to hit the nucleus with a free neutron, which will also cause the nucleus to break apart. Nuclear energy emission through fusion process occurs when nuclei of two light elements combine.

The most favorable fusion reactions involve the element deuterium. Deuterium is a natural component of water and thus is a very abundant fuel. The fusion reaction takes place only when the nuclei have a high enough speed to overcome the electrostatic repulsion of their charges.

Definition of Nuclear Energy – Fusion

In either way of fission and fusion, a significant amount of energy is released when the nucleus splits inside a nuclear reactor. The energy released from the reaction is of two forms; one is light energy and another is heat energy. From a nuclear reaction, some radioactivity is also produced.

Definition of Nuclear Energy

While the atomic bombs let this energy out all at once creating an explosion, in the nuclear reactors this energy is out comparatively very slowly in a continuous chain reaction finally making the electric energy.

Once a nuclear reaction takes place, lighter atoms are produced along with the released energy. Then more free neutrons are found in this way which in turn can take part in further nuclear reaction to continue the process. From the definition of nuclear energy as well as the detail process involved in the same it is well-understood that the nuclear energy can become a source of substantial amounts of energy in many countries.

I hope this post has helped you find the definition of nuclear energy.

Wind Power Pros and Cons

Posted on December 21, 2011 by Chris West

Both of the wind power pros and cons are equally important to consider in terms of the environmental issues and also with the challenge of power generation world-wide.

Wind Power Pros and Cons – Pros

Pretty Flamingos - Off shore wind turbines bathed in mist and warm autumnal sunshine. The turbines are located on Burbo Bank about 4 miles offshore

Wind power has many advantages. One of them is, in contrast to fossil fuels, wind power is inexhaustible and renewable. So wind power is considered as clean. In addition, wind power does not contribute to acid rain, smog, global warming, or mercury contamination. It does not produce or release dangerous particles into the air. The risk that the public will be harmed by a wind-power facility is nearly zero. So, wind power is also considered as safe.

Wind Power Advantages

Small turbines of wind power farm can power schools, businesses, campuses, homes, farms, and ranches. They can be also used in remote locations for telecommunications, ice making, and water pumping. This could eliminate the need for remote communities to run smoky and noisy diesel-powered generators. Because energy from wind power is clean and does not consume water, the use of wind power benefits the environment.

In 2004, it has been estimated that, existing wind power prevented the release of 10.6 million tons of carbon dioxide, 56,000 tons of sulfur dioxide, and 33,000 tons of nitrogen oxides. It also has been estimated that total carbon dioxide emissions could be cut by one-third if only ten percent of wind potential were developed in the ten windiest U.S. states.

Wind Power Pros and Cons – Cons

There are several cons i.e., disadvantages of wind power. Most of the disadvantages come from the operation of wind turbine from which wind power is produced. One important of them is that wind turbines can be noisy. Although the engineers are working on ways to quiet the noise of wind turbines, till now success regarding this issue is not of such extent. Wind turbine blades can cause shadow flicker as the blades rotate in the path of the sun’s rays.

The flickering of light and dark can be, although a minor, annoyance for local residents when the sun is low in the sky. Another important problem is that wind turbines are visible which contribute to visual or horizon pollution. Wind towers and rotors can interfere with radar, posing a potential hazard for air travelers. They can also create problem to or can interfere with television and radio transmission, particularly if they are in the line of sight between the signal source and the receiver. Finally, wind turbines can be a hazard to natural life of birds, which sometimes fly into the rotors. So, both of wind power pros and cons should be taken into consideration before making any plan regarding them.

Wind Power Pros and Cons – The Future of Wind Power?

(click to enlarge images)

Global Wind Power Cumulative Capacity with Forcast

Global Wind Power Cumulative Capacity with Forecast. Wind Power Pros and Cons.

Global Wind Power Cumulative Capacity

What is Hydropower?

Posted on December 18, 2011 by Chris West

What is hydropower? (also called hydraulic power, hydrokinetic power or water power) Any type of power or energy produced by using the energy of water is generally called hydropower. That means, hydropower includes the production of electricity from water which particularly called the hydroelectric power but besides this there are many other uses of hydropower. Waterwheels, the primitive simple form for hydropower generation, are used for low-level electrical power generation.

A Pelamis wave device under test at the European Marine Energy Centre (EMEC), Orkney, Scotland.

In early periods, mechanical energy produced in the waterwheels was transferred through gears to machinery that accomplishes the task at hand. In the past this machinery was very often a large stone used to grind grain, so there was no production of electricity but only to grind something. But It would also used to saws in a sawmill, bellows in a foundry, looms in a textile mill, abrasive tools for polishing metal, pumps for removing water from a mine, and many other applications.

What is Hydropower in Britain?

The British Hydropower Association provides detailed information about building small waterwheel power plants to generate hydropower. Typically, such a plant would involve the following: a water intake from a river or stream, a small canal to channel the water, a tank, where the water is slowed so that debris can settle out, along with a trash rack to filter out debris, a penstock, which shoots the water downward to the turbine, a powerhouse, which contains a turbine where the power is actually generated, and a tailrace, which channels the water back into the river or Stream.

What is Hydropower in Construction?

Constructing such a modern hydropower plant is expensive for the amount of energy it can produce. Production of hydropower can also be hampered since there is generally a variability of water flow in different seasons. During spring runoff, when snow is melting and rivers run rapidly, the amount of power generated is much higher than in, say, August, when rivers are running low, providing less flow. Another problem with hydropower plant is that they require a great deal of maintenance.

What is Hydropower in Production?

What is Hydropower? Saint Anthony Falls, United States.

Production and use of hydropower can be beneficial also. In fact, prior to the industrial revolution, waterwheels were essentially the only form of alternative energy available. Waterwheel use expanded rapidly in England, France, and other European nations as a way to replace lost labor. In modern times waterwheels are used primarily for low-level electrical power generation. It has been noted that 70 to 90 percent of the available power can actually be obtained by that, exactly what is hydropower.

What Is Hydroelectric Power?

Posted on December 16, 2011 by Chris West

While answering the question “what is hydroelectric power”, it is a good approach to start with its exact definition.

Hydroelectric power or hydroelectricity is any electricity which has been generated by using energy contained in water. Most often hydroelectric power refers to the electricity generated by hydroelectric dams. These dams first harness the kinetic energy contained in the moving water of a river and convert it to mechanical energy with the help of a turbine. Then, the turbine converts the energy into electrical energy that can be distributed to thousands, even millions, of users.

How Do We Use Hydroelectricity? Penstocks

Penstocks at the Ohakuri Dam, New Zealand

What is Hydroelectric Power Used For?

A hydroelectric dam with which hydroelectric power is produced consists of several components. Some important components are dam, intake, turbine, generator, transformer, power lines, outflow etc. The dam is built to hold back water, which is contained in a reservoir. This water is regarded as stored energy, which is then released as kinetic energy when the dam operators allow water to flow. Intakes are gates which open to allow the water in the reservoir to flow into a penstock, which is a pipeline that leads to the turbine.

What is Hydroelectric Power – The Francis Turbine

The water gathers kinetic energy as it flows downward through the penstock, which serves to “shoot” the water at the turbine. A turbine is in many ways like the blades of a windmill or the veins of a pinwheel. The water flows past the turbine, striking its blades and turning it. The most common turbine design used in large, modern hydroelectric power plants is the so called Francis turbine, which is a disc with curved blades. It is well mentionable here that the Francis turbine was developed by British-American engineer James B. Francis.

: The upper reservoir (Llyn Stwlan) and dam of the Ffestiniog Pumped Storage Scheme in north Wales. The four water turbines at the power station can generate 360 MW of electricity within 60 seconds of the need arising.

These turbines practically are enormous in the largest hydroelectric power plants, weighing up to 170 tons or more.

What is Hydroelectric Power – How Much Power?

It is the generator in the hydroelectric power plant which actually produces the electric power. The turbine is attached by a shaft to the generator. In a hydroelectric plant, the mechanical energy is supplied by the turbine, which in turn is powered by the kinetic energy of moving water. The transformer converts the alternating current produced by the generator and converts it into a higher voltage current. Then the power lines transmit the power out of the power plant to the electrical grid, where it can be used by consumers. With the help of all of these important components energy in water is converted to electric power that is exactly what is hydroelectric power.

Solar Power Advantages And Disadvantages

Posted on December 15, 2011 by Chris West

A clear understanding of solar power advantages and disadvantages is very important while going to use such power in everyday life. One of the primary benefits to solar energy is that it is a renewable resource. In everywhere sunshine is available which can be used to generate solar power. Most of the solar technologies are environment-friendly. Since solar energy does not contribute to pollution, it is considered as a “clean” energy source. Solar power does not pollute the atmosphere by emitting greenhouse gases. Like nuclear energy, solar power does not produce radioactive waste like, and it does not contribute to global warming or acid rain. When they operate, most solar power systems are silent or quiet, which cuts down on noise pollution.

Nellis Solar Power Plant, 14 MW power plant installed 2007 in Nevada, USA

Solar Power Advantages And Disadvantages – Advantages

Adoption of solar energy technologies can have a profound impact on the economies of individual communities, states, and countries. Countries can be more energy-independent by using solar power. The spread of solar power technologies could lead to electrical power to be available where it was not available before. Particularly people who live in rural areas are often not connected to an electrical power grid; this is especially true in poorer, less developed, and sometime in developing countries also. It has been reported that in 2000, more than two billion people worldwide did not have access to electricity. Solar power technologies could provide energy to these communities.

Solar Power Advantages And Disadvantages – Disadvantages

Solar power has several disadvantages also. The cost of the technology is one of the biggest drawbacks to using solar energy. Solar photovoltaic cells or solar PV cells and solar collectors are still very expensive. Although the technology may become cheaper over time, it is still costly when compared to the amount of energy it will produce over its use cycle. It is also very expensive to build solar power towers and furnaces.

Especially while planning to use such technology to generate power on a wide scale is too expensive to be used realistically, at least till now—at the early twenty-first century. There is another major problem with solar power technology is that solar energy is not available on demand in every location on Earth. Heavy cloud cover, for example, can limit the use of some solar power systems.

Despite the existence of both—solar power advantages and disadvantages—if the solar power technologies that make electricity on a significant scale can be adopted, many countries can lessen their dependence on electricity produced by fossil fuels while causing no pollution to the environment.

Hydrogen Uses in Vehicles & Fuel Cells

Posted on December 14, 2011 by Chris West

What are some hydrogen uses?

Firstly, hydrogen can be used as a fuel source. The most developed, and also most commonly researched, application of using hydrogen as a fuel source is in conjunction with a hydrogen fuel cell. In the operation of fuel cells, by mixing hydrogen and oxygen water and electricity is produced. The produced electricity then can be used to provide power to homes, schools, and even businesses or to power cars and other vehicles.

The internal combustion engines, shortly ICEs, can be fueled by hydrogen and thus can play important role in producing energy by using hydrogen. Hydrogen could be used as fuel for transportation, if those ICEs are created for vehicles that run on hydrogen or hydrogen fuel mixtures.

Demonstration model of a direct-methanol fuel cell. The actual fuel cell stack is the layered cube shape in the center of the image

Hydrogen Uses – Fuel Cells

In hydrogen fuel cells, the hydrogen is converted to electricity through an electrochemical reaction. There are several types of fuel cells which use hydrogen while using different electrolytes—a substance that conducts electricity. For example, some of those fuel cells use phosphoric acid as an electrolyte. Others use molten carbonate as electrolytes. The most common type of hydrogen fuel cell in use is the proton exchange membrane, shortly the PEM fuel cell. This type of fuel cell was first invented by General Electric in 1960s as a source of electrical power for the Gemini spacecraft. Although they were expensive, these fuel cells were efficient in producing energy.

The PEM fuel cells are usually stacked when they are used in vehicles. That means to provide a significant amount of energy a number of identical fuel cells are put together. More voltage will be created if more fuel cells are put together. The number of fuel cells stacked in each vehicle varies according to the amount of power needed from that vehicle.

Hydrogen Uses – In Vehicles

Attribution: Shanghai Pearl hydrogen power source technology Co.

In early states, fuel cells were used in the United States’ space programs. But now most discussion of hydrogen fuel cells has focused on vehicles such as cars, buses, and vans. Presently, a number of countries throughout the world are using hydrogen fuel cell-powered buses on an experimental basis. In addition, most major car companies around the world are working on fuel cell technology in different forms. Each company has produced its own concept and is working toward building such cars on a mass scale.

Though most of the attention with hydrogen uses has focused on hydrogen fuel cells in vehicles, there is a fact that hydrogen fuel cell-powered generators are already being used in at least 600 buildings around the world. In particular, hydrogen uses is getting popular in hospitals, data centers, and office buildings, all of which are using hydrogen fuel technology in their backup generators.

How Does A Wind Turbine Work?

Posted on December 13, 2011 by Chris West

If you’re wondering “How does a wind turbine work?” then you’re obviously interested in it’s operation. So…

How Does A Wind Turbine Work? – The Mechanics

It’s mechanical technique, in fact, is simple. At first, wind turbines capture the kinetic energy of wind. This task is accomplished, in most cases, with two or three blades shaped much like airplane propellers. These blades are attached to a tower that rises at least 30 meters above the ground. The reason behind this height is that air currents tend to be stronger but less turbulent than they are at ground level.

How Does A Wind Turbine Work? The three primary types:VAWT Savonius, HAWT towered; VAWT Darrieus as they appear in operation.

The blades are designed in such a fashion that when the wind strikes the blade, the angle and configuration of the blade form a pocket of low pressure on the downwind side of the blade. This low pressure sucks the blade into movement which causes the rotor to turn. Then, force is added by the high pressure on the upward side of the blade. This property is called lift in aerodynamic theory. In wind turbines lift and drag work together to make the entire mechanism spin like a propeller. It is drag rather than lift that was the force that turned the blades in earlier windmills.

How Does A Wind Turbine Work? – The Components

A wind turbine, in general, composed of several components. Rotor and blades, where rotor is the hub around which the blades are connected. Nacelle (nuh-SELL), or the enclosure that houses the turbine’s drive train, including the gearbox, and the electric generator. A Tower, or the support for the rotor. There are also some electric equipment such as controls, cables, and an anemometer.

The most important feature in the operation of wind turbines is lift. To achieve lift, wind turbines are designed applying the same technology as in aircraft. But unlike airplane wings, wind turbine wings are almost always twisted.

Because of this feature, unlike airplane wings, wind turbine blades are constantly rotating, and the speed of the rotation differs along the entire length of the blade. Moreover, the process operating in a wind turbine is opposite to that of a fan. Where with a fan, electricity is used to make wind; with a wind turbine wind is used to produce electricity. The turning rotor of a wind turbine is connected to a shaft, which is connected to an electric generator.

Power can be distributed to users over the electric grid in exactly the same way any other electric power is distributed. The steadiness and extent of producing electricity may vary due to different turbines. I hope that answers you question: “How does a Wind Turbine Work.”

Green Home Design Ideas & Information

Posted on December 12, 2011 by Chris West

Green home design is an environment-friendly practice which is applied to the buildings with their construction materials as well as with the interior designing. Those buildings designed with this practice are also called as climate-responsive buildings, green buildings or sustainable buildings. The philosophy of green home design, in a broad sense, emphasizes the construction of buildings that use resources efficiently, both during their construction and once completed. Another goal in this practice is to minimize the impact of the building on the surrounding natural environment.

Challenges To Green Home Design?

Several issues such as the placement of the home-building, its design, layout etc. are taken in consideration in order to take advantages of local weather conditions to reduce energy-use during the building’s operation. During their construction, uses of alternative construction materials that reduce energy demands are given the great importance.

U.S. Environmental Protection Agency (EPA), Kansas City Science and Technology Center

The goal of green home design is sustainable building design. Here sustainability refers to any technique that enables the human community to sustain the natural environment for the future by using building materials and sources of energy that are renewable. So, while designing such buildings, the use of green-building materials, is given priority.

In green home designing, instead of simply putting buildings anywhere and relying on fossil fuels to heat, cool, ventilate, and light them, more attention is given to local climatic conditions to make buildings far more energy-efficient. In such techniques buildings are not considered just as collections of steel, glass, wood, and other materials, but as systems that interact with their natural environment. Such buildings then can consume less energy while still providing for the comfort of their occupants.

Solar Energy In Green Home Design

Presence of available solar energy is ensured in a green-designed home, which in turn can be used for heating and lighting. For the same purpose, daylighting, or using natural sunlight can be used. Other techniques may include solar ventilation preheating, and solar buffer spaces to provide some of the building’s heat; heating of solar water; and the use of photovoltaic cells to provide electricity.

John Willoner's Eco-House at Findhorn. Turf roof, passive solar, solar panel.

To use daylighting and solar energy in the purpose of heating and lighting, the intelligent placement of the building relative to the sun is required. Features such as heating of solar water and use of photovoltaic cells can be built right into the skin and roof of the building, as well as into shingles, roofing tiles, glass walls, and even into ornamental features. There are other techniques practiced in green home design to prepare such homes as net energy producers, in addition, creating surplus power that can be sold to the local energy grid or traded.