7.3.4 Turbine – A steam turbine is a form of steam engine that extracts thermal energy from pressurized steam and converts it to rotary motion which is used to drive an electrical generator. A solar turbine works on the same principle as any steam-driven generator powered by the fossil fuels except the way the steam is produced to power the turbine.
In a solar turbine, steam is generated by using a transmission fluid that is heated by capturing sunlight with a number of parabolic mirrors which in turn boils the water. The most important difference between powering steam turbines by fossil fuels and solar energy is the operation cycle. Due to the intermittent nature of solar radiation, solar turbines need to work efficiently during repeated starts and stops throughout the day.
As a result, steam turbines for CSP plants should match the applications specific demands including a number of starts, rapid-startup capabilities and re-heat options for maximum performance. One weakness of the current solar turbine is that transmission fluids cannot be heated above 400°C, although turbines are capable of operating with steam heated up to 540°C which would generate more power.
- This shortcoming could be overcome by placing the turbine on a high tower with the mirrors aimed to focus the sunlight directly on the steam boiler instead of using transmission fluid in the pipes.
- The majority of CSP plants except the parabolic dish operate according to Rankine thermodynamic cycle, wherein a steam turbine coupled to an alternator converts thermal energy into electricity.
Steam turbines are only practical for very large CSP installations. Read full chapter URL: https://www.sciencedirect.com/science/article/pii/B9780128030226000071
- 0.1 Can sun power the world?
- 1 How a gas turbine works solar?
- 2 How long do wind turbines last?
- 3 What is the main way we turn turbines in the US?
- 4 How do rotating wheels generate electricity?
- 5 Can I use a solar charge controller for a wind turbine?
Can solar energy be used to turn turbines?
Energy can be harnessed directly from the sun, even in cloudy weather. Solar energy is used worldwide and is increasingly popular for generating electricity, and heating or desalinating water. Solar power is generated in two main ways: Solar photovoltaic (PV) uses electronic devices, also called solar cells, to convert sunlight directly into electricity.
- It is one of the fastest-growing renewable energy technologies and is playing an increasingly important role in the global energy transformation.
- The total installed capacity of solar PV reached 710 GW globally at the end of 2020.
- About 125 GW of new solar PV capacity was added in 2020, the largest capacity addition of any renewable energy source.
Solar PV is highly modular and ranges in size from small solar home kits and rooftop installations of 3-20 kW capacity, right up to systems with capacity in the hundreds of megawatts. It has democratised electricity production. The cost of manufacturing solar panels has plummeted dramatically in the past decade, making them not only affordable, but also often the cheapest form of electricity.
- Solar module prices fell by up to 93% between 2010 and 2020,
- During the same period, the global weighted-average levelised cost of electricity (LCOE) for utility-scale solar PV projects fell by 85%.
- Concentrated solar power (CSP) uses mirrors to concentrate solar rays.
- These rays heat fluid, which creates steam to drive a turbine and generate electricity.
CSP is used to generate electricity in large-scale power plants. By the end of 2020, the global installed capacity of CSP was approaching 7 GW, a fivefold increase between 2010 and 2020. It is likely that some 150 MW was commissioned in 2020, although official statistics only captured 100 MW.
- It is possible to classify CSP systems according to the mechanism by which the solar collectors concentrate solar irradiation: either “linear concentrating” or “point concentrating” varieties.
- Most existing systems use linear concentrating systems called parabolic trough collectors.
- Solar towers, sometimes also known as power towers, are the most widely deployed point concentrating CSP technology, but represented only around a fifth of all systems deployed at the end of 2020.
One of the main advantages of a CSP power plant over a solar PV power plant is that it can be equipped with molten salts in which heat can be stored, allowing electricity to be generated after the sun has set. As the market has matured, the cost of thermal energy storage has declined, making storage duration of 12 hours economic.
How does a solar turbine work?
Solar Turbine – Concentrated Solar Power A solar turbine works by using concentrated solar power to create steam. Concentrated solar power is a sunlight capturing technique that converts the sun’s light into heat energy.
- The heat energy is then used to convert water into steam, which can be used in to create an electric current.
- The sunlight is converted into heat energy when the sun’s rays are reflected off a smooth, mirrored surface towards a heat capturing focal point.
- When this focal point is targeted by the reflected sunlight of several mirrored surfaces, enough heat energy is created to heat water to extreme temperatures and eventually into steam.
- Below is a step-by-step diagram of a basic concentrated solar power system.
The above diagram is an example of a concentrated solar power system using a reflective mirrored surface to intensify the heat of the sun. Think about using a magnifying glass to concentrate the sunlight on a specific point, concentrated solar power uses the same technique only that a large system of mirrors is used instead.
- The panels with the mirrored surfaces reflect the rays of the sun into one targeted focal point.
- At this focal point the heat from the sun is greatly intensified.
- At these high temperatures the water is converted into steam and pumped through special steam tubes out of the reflective mirrored panel area and into a heat exchanger.
- The heat exchanger retrieves the steam and sets it to the correct temperature and pressure needed for the steam turbine generator.
- The steam turbine generator uses the steam to create electricity.
- The cooled steam is then passed out of the generator, again through the heat exchanger, converted back into water and again pumped back towards the heated focal point of the mirrors, and the process is repeated.
It is important to remember that a solar turbine generator system actually uses a steam turbine generator to create the electricity. The solar energy is what it used to heat water into steam. This process of heating using concentrated solar power is a form of clean renewable energy. No pollutants are emitted during the water heating process. : Solar Turbine – Concentrated Solar Power
What can turn the turbine in the power plant?
Turbine driven generators – Most of U.S. and world electricity generation is from electric power plants that use a turbine to drive electricity generators. In a turbine generator, a moving fluid—water, steam, combustion gases, or air—pushes a series of blades mounted on a rotor shaft. Steam turbines are used to generate the majority of the world’s electricity and they accounted for about 44% of U.S. electricity generation in 2020. Most steam turbines have a boiler in which a fuel is burned to produce hot water and steam in a heat exchanger, and the steam powers a turbine that drives a generator.
Nuclear power reactors use nuclear fuel rods to produce steam. Solar thermal power plants and most geothermal power plants use steam turbines. Most of the largest U.S. electric power plants use steam turbines. Combustion gas turbines, which are similar to jet engines, burn gaseous or liquid fuels to produce hot gases to turn the blades in the turbine.
Steam and combustion turbines can be operated as stand-alone generators in a single-cycle or combined in a sequential combined-cycle. Combined-cycle systems use combustion gases from one turbine to generate more electricity in another turbine. Most combined-cycle systems have separate generators for each turbine.
- In single-shaft combined cycle systems, both turbines may drive a single generator.
- Learn more about different types of combined-cycle power plants,
- In 2020, combined-cycle power plants supplied about 35% of U.S.
- Net electricity generation,
- Combined-heat-and-power (CHP) plants, which may be referred to as cogenerators, use the heat that is not directly converted to electricity in a steam turbine, combustion turbine, or an internal combustion engine generator for industrial process heat or for space and water heating.
Most of the largest CHP plants in the United States are at industrial facilities such as pulp and paper mills, but they are also used at many colleges, universities, and government facilities. CHP and combined-cycle power plants are among the most efficient ways to convert a combustible fuel into useful energy.
Hydroelectric turbines use the force of moving water to spin turbine blades to power a generator. Most hydroelectric power plants use water stored in a reservoir or diverted from a river or stream. These conventional hydroelectric power plants accounted for about 7% of U.S. electricity generation in 2020.
Pumped-storage hydropower plants use the same types of hydro turbines that conventional hydropower plants use, but they are considered electricity storage systems (see below). Other types of hydroelectric turbines called hydrokinetic turbines are used in tidal power and wave power systems.
Learn more about different types of hydroelectric turbines, Wind turbines use the power in wind to move the blades of a rotor to power a generator. There are two general types of wind turbines : horizontal axis (the most common) and vertical-axis turbines. Wind turbines were the source of about 8% of U.S.
electricity generation in 2020. Ocean thermal energy conversion (OTEC) systems use a temperature difference between ocean water at different depths to power a turbine to produce electricity.
What causes the turbine to turn in the electricity?
Wind turbines work on a simple principle: instead of using electricity to make wind—like a fan—wind turbines use wind to make electricity. Wind turns the propeller-like blades of a turbine around a rotor, which spins a generator, which creates electricity. Wind is a form of solar energy caused by a combination of three concurrent events:
The sun unevenly heating the atmosphereIrregularities of the earth’s surfaceThe rotation of the earth.
Wind flow patterns and speeds vary greatly across the United States and are modified by bodies of water, vegetation, and differences in terrain. Humans use this wind flow, or motion energy, for many purposes: sailing, flying a kite, and even generating electricity.
- The terms “wind energy” and “wind power” both describe the process by which the wind is used to generate mechanical power or electricity.
- This mechanical power can be used for specific tasks (such as grinding grain or pumping water) or a generator can convert this mechanical power into electricity.
- A wind turbine turns wind energy into electricity using the aerodynamic force from the rotor blades, which work like an airplane wing or helicopter rotor blade.
When wind flows across the blade, the air pressure on one side of the blade decreases. The difference in air pressure across the two sides of the blade creates both lift and drag. The force of the lift is stronger than the drag and this causes the rotor to spin.
Can sun power the world?
Solar energy is any type of energy generated by the sun, Solar energy is created by nuclear fusion that takes place in the sun, Fusion occurs when protons of hydrogen atoms violently collide in the sun ‘s core and fuse to create a helium atom. This process, known as a PP (proton-proton) chain reaction, emits an enormous amount of energy.
In its core, the sun fuses about 620 million metric tons of hydrogen every second. The PP chain reaction occurs in other stars that are about the size of our sun, and provides them with continuous energy and heat. The temperature for these stars is around 4 million degrees on the Kelvin scale (about 4 million degrees Celsius, 7 million degrees Fahrenheit).
In stars that are about 1.3 times bigger than the sun, the CNO cycle drives the creation of energy. The CNO cycle also converts hydrogen to helium, but relies on carbon, nitrogen, and oxygen (C, N, and O) to do so. Currently, less than 2% of the sun ‘s energy is created by the CNO cycle.
Nuclear fusion by the PP chain reaction or CNO cycle releases tremendous amounts of energy in the form of waves and particles. Solar energy is constantly flowing away from the sun and throughout the solar system, Solar energy warms the Earth, causes wind and weather, and sustains plant and animal life.
The energy, heat, and light from the sun flow away in the form of electromagnetic radiation (EMR). The electromagnetic spectrum exists as waves of different frequencies and wavelengths. The frequency of a wave represents how many times the wave repeats itself in a certain unit of time.
Waves with very short wavelengths repeat themselves several times in a given unit of time, so they are high- frequency, In contrast, low- frequency waves have much longer wavelengths. The vast majority of electromagnetic waves are invisible to us. The most high- frequency waves emitted by the sun are gamma rays, X-rays, and ultraviolet radiation (UV rays).
The most harmful UV rays are almost completely absorbed by Earth’s atmosphere, Less potent UV rays travel through the atmosphere, and can cause sunburn, The sun also emits infrared radiation, whose waves are much lower- frequency, Most heat from the sun arrives as infrared energy.
- Sandwiched between infrared and UV is the visible spectrum, which contains all the colors we see on Earth.
- The color red has the longest wavelengths (closest to infrared), and violet (closest to UV) the shortest.
- Natural Solar Energy Greenhouse Effect The infrared, visible, and UV waves that reach the Earth take part in a process of warming the planet and making life possible—the so-called ” greenhouse effect,” About 30% of the solar energy that reaches Earth is reflected back into space.
The rest is absorbed into Earth’s atmosphere, The radiation warms the Earth’s surface, and the surface radiates some of the energy back out in the form of infrared waves. As they rise through the atmosphere, they are intercepted by greenhouse gases, such as water vapor and carbon dioxide.
- Greenhouse gases trap the heat that reflects back up into the atmosphere.
- In this way, they act like the glass walls of a greenhouse.
- This greenhouse effect keeps the Earth warm enough to sustain life.
- Photosynthesis Almost all life on Earth relies on solar energy for food, either directly or indirectly.
Producers rely directly on solar energy, They absorb sunlight and convert it into nutrients through a process called photosynthesis, Producers, also called autotrophs, include plants, algae, bacteria, and fungi. Autotrophs are the foundation of the food web,
Consumers rely on producers for nutrients, Herbivores, carnivores, omnivores, and detritivores rely on solar energy indirectly. Herbivores eat plants and other producers. Carnivores and omnivores eat both producers and herbivores. Detritivores decompose plant and animal matter by consuming it. Fossil Fuels Photosynthesis is also responsible for all of the fossil fuels on Earth.
Scientists estimate that about 3 billion years ago, the first autotrophs evolved in aquatic settings. Sunlight allowed plant life to thrive and evolve. After the autotrophs died, they decomposed and shifted deeper into the Earth, sometimes thousands of meters.
This process continued for millions of years. Under intense pressure and high temperatures, these remains became what we know as fossil fuels, Microorganisms became petroleum, natural gas, and coal. People have developed processes for extracting these fossil fuels and using them for energy. However, fossil fuels are a nonrenewable resource,
They take millions of years to form. Harnessing Solar Energy Solar energy is a renewable resource, and many technologies can harvest it directly for use in homes, businesses, schools, and hospitals. Some solar energy technologies include photovoltaic cells and panels, concentrated solar energy, and solar architecture,
There are different ways of capturing solar radiation and converting it into usable energy. The methods use either active solar energy or passive solar energy, Active solar technologies use electrical or mechanical devices to actively convert solar energy into another form of energy, most often heat or electricity.
Passive solar technologies do not use any external devices. Instead, they take advantage of the local climate to heat structures during the winter, and reflect heat during the summer. Photovoltaics Photovoltaics is a form of active solar technology that was discovered in 1839 by 19-year-old French physicist Alexandre-Edmond Becquerel.
Becquerel discovered that when he placed silver-chloride in an acidic solution and exposed it to sunlight, the platinum electrodes attached to it generated an electric current, This process of generating electricity directly from solar radiation is called the photovoltaic effect, or photovoltaics,
Today, photovoltaics is probably the most familiar way to harness solar energy, Photovoltaic arrays usually involve solar panels, a collection of dozens or even hundreds of solar cells. Each solar cell contains a semiconductor, usually made of silicon.
- When the semiconductor absorbs sunlight, it knocks electrons loose.
- An electrical field directs these loose electrons into an electric current, flowing in one direction.
- Metal contacts at the top and bottom of a solar cell direct that current to an external object.
- The external object can be as small as a solar-powered calculator or as large as a power station.
Photovoltaics was first widely used on spacecraft. Many satellites, including the International Space Station, feature wide, reflective “wings” of solar panels, The ISS has two solar array wings (SAWs), each using about 33,000 solar cells. These photovoltaic cells supply all electricity to the ISS, allowing astronauts to operate the station, safely live in space for months at a time, and conduct scientific and engineering experiments.
- Photovoltaic power stations have been built all over the world.
- The largest stations are in the United States, India, and China.
- These power stations emit hundreds of megawatts of electricity, used to supply homes, businesses, schools, and hospitals.
- Photovoltaic technology can also be installed on a smaller scale.
Solar panels and cells can be fixed to the roofs or exterior walls of buildings, supplying electricity for the structure. They can be placed along roads to light highways. Solar cells are small enough to power even smaller devices, such as calculators, parking meters, trash compactors, and water pumps.
- Concentrated Solar Energy Another type of active solar technology is concentrated solar energy or concentrated solar power (CSP).
- CSP technology uses lenses and mirrors to focus (concentrate) sunlight from a large area into a much smaller area.
- This intense area of radiation heats a fluid, which in turn generates electricity or fuels another process.
Solar furnaces are an example of concentrated solar power. There are many different types of solar furnaces, including solar power towers, parabolic troughs, and Fresnel reflectors. They use the same general method to capture and convert energy. Solar power towers use heliostats, flat mirrors that turn to follow the sun ‘s arc through the sky.
- The mirrors are arranged around a central “collector tower,” and reflect sunlight into a concentrated ray of light that shines on a focal point on the tower.
- In previous designs of solar power towers, the concentrated sunlight heated a container of water, which produced steam that powered a turbine,
More recently, some solar power towers use liquid sodium, which has a higher heat capacity and retains heat for a longer period of time. This means that the fluid not only reaches temperatures of 773 to 1,273 K (500 to 1,000° C or 932 to 1,832° F), but it can continue to boil water and generate power even when the sun is not shining.
- Parabolic troughs and Fresnel reflectors also use CSP, but their mirrors are shaped differently.
- Parabolic mirrors are curved, with a shape similar to a saddle.
- Fresnel reflectors use flat, thin strips of mirror to capture sunlight and direct it onto a tube of liquid.
- Fresnel reflectors have more surface area than parabolic troughs and can concentrate the sun ‘s energy to about 30 times its normal intensity.
Concentrated solar power plants were first developed in the 1980s. The largest facility in the world is a series of plants in California’s Mojave Desert. This Solar Energy Generating System (SEGS) generates more than 650 gigawatt-hours of electricity every year.
Other large and effective plants have been developed in Spain and India. Concentrated solar power can also be used on a smaller scale. It can generate heat for solar cookers, for instance. People in villages all over the world use solar cookers to boil water for sanitation and to cook food. Solar cookers provide many advantages over wood-burning stoves: They are not a fire hazard, do not produce smoke, do not require fuel, and reduce habitat loss in forests where trees would be harvested for fuel.
Solar cookers also allow villagers to pursue time for education, business, health, or family during time that was previously used for gathering firewood. Solar cookers are used in areas as diverse as Chad, Israel, India, and Peru. Solar Architecture Throughout the course of a day, solar energy is part of the process of thermal convection, or the movement of heat from a warmer space to a cooler one.
- When the sun rises, it begins to warm objects and material on Earth.
- Throughout the day, these materials absorb heat from solar radiation.
- At night, when the sun sets and the atmosphere has cooled, the materials release their heat back into the atmosphere,
- Passive solar energy techniques take advantage of this natural heating and cooling process.
Homes and other buildings use passive solar energy to distribute heat efficiently and inexpensively. Calculating a building’s ” thermal mass ” is an example of this. A building’s thermal mass is the bulk of material heated throughout the day. Examples of a building’s thermal mass are wood, metal, concrete, clay, stone, or mud.
At night, the thermal mass releases its heat back into the room. Effective ventilation systems—hallways, windows, and air ducts—distribute the warmed air and maintain a moderate, consistent indoor temperature. Passive solar technology is often involved in the design of a building. For example, in the planning stage of construction, the engineer or architect may align the building with the sun ‘s daily path to receive desirable amounts of sunlight,
This method takes into account the latitude, altitude, and typical cloud cover of a specific area. In addition, buildings can be constructed or retrofitted to have thermal insulation, thermal mass, or extra shading. Other examples of passive solar architecture are cool roofs, radiant barriers, and green roofs,
- Cool roofs are painted white, and reflect the sun ‘s radiation instead of absorbing it.
- The white surface reduces the amount of heat that reaches the interior of the building, which in turn reduces the amount of energy that is needed to cool the building.
- Radiant barriers work similarly to cool roofs.
They provide insulation with highly reflective materials, such as aluminum foil. The foil reflects, instead of absorbs, heat, and can reduce cooling costs up to 10%. In addition to roofs and attics, radiant barriers may also be installed beneath floors.
- Green roofs are roofs that are completely covered with vegetation,
- They require soil and irrigation to support the plants, and a waterproof layer beneath.
- Green roofs not only reduce the amount of heat that is absorbed or lost, but also provide vegetation,
- Through photosynthesis, the plants on green roofs absorb carbon dioxide and emit oxygen.
They filter pollutants out of rainwater and air, and offset some of the effects of energy use in that space. Green roofs have been a tradition in Scandinavia for centuries, and have recently become popular in Australia, Western Europe, Canada, and the United States.
- For example, the Ford Motor Company covered 42,000 square meters (450,000 square feet) of its assembly plant roofs in Dearborn, Michigan, with vegetation,
- In addition to reducing greenhouse gas emissions, the roofs reduce stormwater runoff by absorbing several centimeters of rainfall.
- Green roofs and cool roofs can also counteract the ” urban heat island ” effect.
In busy cities, the temperature can be consistently higher than the surrounding areas. Many factors contribute to this: Cities are constructed of materials such as asphalt and concrete that absorb heat; tall buildings block wind and its cooling effects; and high amounts of waste heat is generated by industry, traffic, and high populations.
- Using the available space on the roof to plant trees, or reflecting heat with white roofs, can partially alleviate local temperature increases in urban areas.
- Solar Energy and People Since sunlight only shines for about half of the day in most parts of the world, solar energy technologies have to include methods of storing the energy during dark hours.
Thermal mass systems use paraffin wax or various forms of salt to store the energy in the form of heat. Photovoltaic systems can send excess electricity to the local power grid, or store the energy in rechargeable batteries. There are many pros and cons to using solar energy,
- Advantages A major advantage to using solar energy is that it is a renewable resource,
- We will have a steady, limitless supply of sunlight for another 5 billion years.
- In one hour, the Earth’s atmosphere receives enough sunlight to power the electricity needs of every human being on Earth for a year.
Solar energy is clean. After the solar technology equipment is constructed and put in place, solar energy does not need fuel to work. It also does not emit greenhouse gases or toxic materials. Using solar energy can drastically reduce the impact we have on the environment.
There are locations where solar energy is practical, Homes and buildings in areas with high amounts of sunlight and low cloud cover have the opportunity to harness the sun ‘s abundant energy. Solar cookers provide an excellent alternative to cooking with wood-fired stoves—on which 2 billion people still rely.
Solar cookers provide a cleaner and safer way to sanitize water and cook food. Solar energy complements other renewable sources of energy, such as wind or hydroelectric energy, Homes or businesses that install successful solar panels can actually produce excess electricity.
These homeowners or businessowners can sell energy back to the electric provider, reducing or even eliminating power bills. Disadvantages The main deterrent to using solar energy is the required equipment. Solar technology equipment is expensive. Purchasing and installing the equipment can cost tens of thousands of dollars for individual homes.
Although the government often offers reduced taxes to people and businesses using solar energy, and the technology can eliminate electricity bills, the initial cost is too steep for many to consider. Solar energy equipment is also heavy. In order to retrofit or install solar panels on the roof of a building, the roof must be strong, large, and oriented toward the sun ‘s path.
Both active and passive solar technology depend on factors that are out of our control, such as climate and cloud cover, Local areas must be studied to determine whether or not solar power would be effective in that area. Sunlight must be abundant and consistent for solar energy to be an efficient choice.
In most places on Earth, sunlight ‘s variability makes it difficult to implement as the only source of energy. Fast Fact Agua Caliente The Agua Caliente Solar Project, in Yuma, Arizona, is the world’s largest array of photovoltaic panels. Agua Caliente has more than 5 million photovoltaic modules, and generates more than 600 gigawatt-hours of electricity.
Fast Fact Green Chicago Millennium Park in Chicago, Illinois, has one of the most expansive green roofs in the worldalmost 100,000 square meters (more than a million square feet). Vegetation at ground level covers 24.5 acres of an underground parking garage, and includes gardens, picnic areas, and an outdoor concert facility.
Fast Fact Solar Decathlon The Solar Decathlon is a biannual international event presented by the U.S. Department of Energy. Teams compete to design, build, and operate the most attractive, effective, and energy-efficient solar-powered house. A team from the University of Maryland won the 2011 contest, and the next Solar Decathlon will be held in 2013,
How a gas turbine works solar?
9.6.1 Turbines description – Turbines are a form of engine and therefore are included in this chapter on engine filtration. Turbines are rotating devices designed to generate energy, either mechanical or electrical. The gas turbine in a jet aircraft engine is an example of mechanical energy generation.
The turbine rotates a compressor that compresses the inlet gas. One or more ignition chamber injects and ignites fuel to heat and expand the gas and provide the exhaust thrust necessary to drive the aircraft. In large-scale power plants, the turbine operates a rotating electrical generator to produce electricity for the realm that is serviced by the power plant.
There are several types of turbines; including steam turbines, hydroelectric, solar turbines, wind turbines, and gas turbines. The complexities of the gas turbine machine are of interest to the filter and filter medium manufacturer, because of stringent requirements for inlet gas cleanliness.
- According to the US Department of Energy (197) gas turbines basically involve three main sections: • The compressor, which draws air into the engine, pressurizes it, and feeds it to the combustion chamber literally at speeds hundreds of miles per hour.
- The combustion system, typically made up of a ring of fuel injectors that inject a steady stream of fuel (e.g.
natural gas) into the combustion chamber where it mixes with the air. The mixture is burned at temperatures of more than 2,000°F. The combustion produces a high temperature, high pressure gas stream that enters and expands through the turbine section. • The turbine is an intricate array of alternate stationary and rotating aerofoil-section blades.
How long do wind turbines last?
How Long do Wind Turbines Last? – A good quality, modern wind turbine will generally last for 20 years, although this can be extended to 25 years or longer depending on environmental factors and the correct maintenance procedures being followed. However, the maintenance costs will increase as the structure ages.
Wind turbines are unlikely to last much longer than this because of the extreme loads they are subjected to throughout their lives. This is partly due to the structure of the turbines themselves, since the turbine blades and the tower are only fixed at one end of the structure and therefore face the full force of the wind.
Of course, as the wind speed increases, so do the loads that turbines are subjected to. This can reach levels almost 100 times greater than the design loads at rated wind speed, which is why many turbines are designed to shut down to protect themselves at higher wind speeds.
What happens when there is no wind for wind turbines?
How can windmills create electricity if they’re so often moving slowly? The short answer is that if they move slowly, they produce less power. But if the wind speed doubles, then a windmill could produce eight times more power under the appropriate conditions.
If there is too little wind and the blades are moving too slowly, the wind turbine no longer produces electricity. The turbine starts to create power at what is known as the cut-in speed. Power output continues to grow as the wind speed increases, but at a slower rate than it does right after the cut-in point.
The turbine then reaches its maximum rated wind speed, above which the power output holds steady under ideal conditions, generally 22 to 36 miles per hour, depending on the type of windmill. Of course, too much wind could damage the turbine, so windmills have a cut-out speed, too.
- After that, a brake stops the windmill’s rotation.
- Windmills are generally rated to the power they would produce in ideal conditions.
- That means the rated power can be different from the actual power produced, because wind conditions depend on seasons and time of day.
- For example, the Cape Wind project—130 turbines slated to be located off Cape Cod—is rated to produce up to 468 megawatts of wind power.
But the average production will only be 170 megawatts, based on varying conditions such as wind speed and wind regularity. Those estimates are based on measurements of wind made before a site is built, so that a wind farm can be designed to harness the maximum power available.
This information is crucial to the efficient utilization of wind power on the existing electric power grid. The housing behind the blades contains the machinery that actually creates the electricity. A gear system increases the original rotational speed of the blades to the high speed needed to generate electricity, converting the mechanical movement of the blades into power.
Occasionally the power available from a wind farm cannot be used, because the consumer demand isn’t there. A great deal of research is currently being done on electricity storage systems—batteries are one example—so that the power produced by this type of renewable energy can be stored and used when it’s needed.
How much steam is needed to turn a turbine?
Condensing and noncondensing – Turbines also vary in how they cool the steam that passes through them. Condensing turbines (used in large power plants to generate electricity) turn the steam at least partly to water using condensers and giant concrete cooling towers.
This allows the steam to expand more and helps the turbine extract the maximum energy from it, making the electricity generating process much more efficient. A large supply of cold water is needed to condense the steam, and that’s why electricity plants with condensing turbines are often built next to large rivers.
Noncondensing turbines don’t cool the steam so much, and use the heat remaining in it to make hot water in a system known as combined heat and power (CHP or cogeneration). Photo: Cooling towers like these help a steam turbine condense steam to extract more energy in a heating-cooling process known as the Rankine cycle, If you’re uncertain why we need cooling towers, check out The Energy Cost of Heat by David MacKay, an extract from his excellent book Sustainable Energy: Without Hot Air.
These are the towers at Didcot power station near Oxford, England. Practical steam turbines come in all shapes and sizes and produce power ranging from one or two megawatts (roughly the same output as a single wind turbine) up to 1,000 megawatts or more (the output from a large power plant, equivalent to 500–1000 wind turbines working at full capacity).
In the biggest turbines, in large fossil-fuel power plants, the steam pressure can be as high as 20–30MPa (3000–4000 psi or about 200–270 times atmospheric pressure). A small, 10 megawatt steam turbine is roughly the same size as a Greyhound bus (a large single-deck passenger coach).
What spins the turbine in a nuclear power plant?
Nuclear power plants – U.S. Energy Information Administration (EIA) Nuclear power plants heat water to produce steam. The steam is used to spin large turbines that generate electricity. Nuclear power plants use heat produced during nuclear fission to heat water.
In nuclear fission, atoms are split apart to form smaller atoms, releasing energy. Fission takes place inside the reactor of a nuclear power plant. At the center of the reactor is the core, which contains uranium fuel. The uranium fuel is formed into ceramic pellets. Each ceramic pellet produces about the same amount of energy as 150 gallons of oil.
These energy-rich pellets are stacked end-to-end in 12-foot metal fuel rods. A bundle of fuel rods, some with hundreds of rods, is called a fuel assembly. A reactor core contains many fuel assemblies. The heat produced during nuclear fission in the reactor core is used to boil water into steam, which turns the blades of a steam turbine.
- As the turbine blades turn, they drive generators that make electricity.
- Nuclear plants cool the steam back into water in a separate structure at the power plant called a cooling tower, or they use water from ponds, rivers, or the ocean.
- The cooled water is then reused to produce steam.
- Nuclear reactors in the United States may have large concrete domes covering the reactors, which are required to contain accidental releases of radiation.
Not all nuclear power plants have cooling towers. Some nuclear power plants use water from lakes, rivers, or the ocean for cooling. Containment dome of a nuclear reactor Source: Stock photography (copyrighted)
What is the main way we turn turbines in the US?
Fossil fuels are the largest sources of energy for electricity generation – Natural gas was the largest source—about 38%—of U.S. electricity generation in 2021. Natural gas is used in steam turbines and gas turbines to generate electricity. Coal was the second-largest energy source for U.S.
- Electricity generation in 2021—about 22%.
- Nearly all coal-fired power plants use steam turbines.
- A few coal-fired power plants convert coal to a gas for use in a gas turbine to generate electricity.
- Petroleum was the source of less than 1% of U.S.
- Electricity generation in 2021.
- Residual fuel oil and petroleum coke are used in steam turbines.
Distillate—or diesel—fuel oil is used in diesel-engine generators, Residual fuel oil and distillates can also be burned in gas turbines.
What is the spinning principle?
BUSINESS TECHNOLOGY; Using Spin to Power Electric Cars (Published 1992) BUSINESS TECHNOLOGY
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Credit. The New York Times Archives See the article in its original context from November 11, 1992, Section D, Page 5 TimesMachine is an exclusive benefit for home delivery and digital subscribers. This is a digitized version of an article from The Times’s print archive, before the start of online publication in 1996.
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- When General Motors introduces its battery-powered Impact in the middle of this decade, the electric automobile will be powered by a souped-up version of a conventional lead-acid battery.
But even though G.M. believes this energy source can make the Impact a viable alternative to gasoline-powered cars, the auto maker concedes that the lead-acid battery may not be the long-term answer for electric vehicles. California has given G.M. and the other auto makers a powerful incentive to develop practical electric cars by requiring the companies to insure that 2 percent of their vehicles have zero emissions by 1998.
- The auto industry’s principal focus is on improving the conventional battery, which has a limited power storage in relation to its weight and takes several hours to recharge.
- Yet even as some scientists and engineers are rethinking the way energy is stored in electric vehicles, others are updating the ancient concept of a mechanical whirling dervish: the flywheel.
Testing New Materials Small groups of university and national laboratory researchers, along with a start-up company in Bellevue, Wash., hope that a flywheel built of new materials will be able to store enough energy to make practical the long-sought ideal of an electric car with a range and acceleration competitive with conventional cars.
- Technically, nothing holds us back today,” says Richard F.
- Post, a researcher at Lawrence Livermore National Laboratory in Livermore, Calif., who is seeking industrial partners to build a flywheel system.
- The materials and the design principles are available.
- What holds us back? There is a huge battery industry but there is no flywheel industry.” The principle of the flywheel is based on kinetic energy, which is the energy of a moving object.
Because a flywheel has a heavy rim, once a force sets it spinning, the wheel tends to keep spinning – a property that makes a flywheel a reservoir of energy. As power is added, the flywheel speeds up; as energy is drawn off in the form of useful work and wasted friction, it gradually slows.
A potter’s wheel, propelled by the occasional spin of its axle by the potter’s foot, is a time-tested version of the flywheel. And most combustion engines, including auto engines, use flywheels to convert the jerky motion of the engine’s exploding cylinders into a smooth and continuous source of power for the drive train.
The concept of using flywheels to power electric vehicles has been around for decades. Buses in Switzerland were powered by giant steel flywheels 40 years ago, but the buses had to be recharged at each stop. Today, flywheel enthusiasts say, advances in technology and materials make the idea more feasible.
- In theory, a flywheel for producing electricity for an electric car would be made of extremely strong composite materials that could spin up to 200,000 revolutions a minute without breaking apart, and would be mounted on special bearings to reduce the friction-caused slowing to a negligible amount.
- At such speeds even a lightweight flywheel is capable of storing enough energy and producing enough power to run an electric car.
The flywheel’s energy would be tapped through electromagnetic means. Magnets spinning on the flywheel would be placed so they passed near coils of wire in a battery housing. This would induce an electric current in the coils. The power would be sent to an electric motor that would drive the axle.
American Flywheel Systems Inc., the Bellevue, Wash., company that received patents last June for its flywheel design, contends its device could power an electric car for 300 to 600 miles on each charge compared with the current 100 miles per charge for G.M.’s Impact. The company says its device could produce 60 to 90 watt-hours a pound.
The battery in the Impact stores 12 to 15 watt-hours a pound, which is only enough energy to keep a night light burning about two hours. By plugging into a standard household electrical outlet, the flywheel could be “spun up,” or recharged, overnight – or as fast as 15 minutes at a special high-powered “flywheel filling station.” Proponents say the cost of the electricity would be competitive with that of gasoline.
Other Projects Flywheel research is also being conducted at Oak Ridge National Laboratory in Tennessee and at the University of Ottawa in Canada. Uniq Mobility, a Denver company, is working on a flywheel that would be integrated with an extremely dense motor to form a hybrid vehicle for urban driving.
Ray A. Geddes, Uniq’s chairman, says Ford, BMW and Fiat have expressed interest. But flywheel technology still faces many hurdles set by nature and public confidence. The American Flywheel Systems design has yet to be turned into a prototype, and skeptics say that until one is working, the device is just another unproved idea.
The Energy Department has joined Ford Motor, G.M. and Chrysler in the United States Advanced Battery Consortium. John R. Wallace, the chairman of the consortium and the director of Ford’s electric vehicles program, said the consortium had not ruled out sponsoring flywheel research. But he acknowledged that the consortium was concentrating on improving conventional batteries.
One concern about flywheels is that the rapidly spinning large wheel, like a gyroscope, would have an inertia of its own. A driver might turn a corner, but the car’s flywheel would want to proceed straight ahead. A second hurdle, which flywheel designers say they have already overcome, is the possibility that the extremely high speeds would cause the flywheel to break apart, sending shrapnel-like pieces in all directions.
Benefits Are Foreseen Should the current bugs be ironed out, flywheels have advantages that make them attractive, at least to theorists. They can produce great acceleration, eight times the horsepower per pound of a V-8 engine. And a concept called regenerative braking would allow energy to be recaptured as the vehicle decelerates instead of being dissipated as heat.
Even better, the flywheel could conceivably last for 200,000 miles or more and is nontoxic, while the lead- acid battery in the Impact must be replaced every two years. Based on some of Dr. Post’s original concepts, Jack G. Bitterly, an aerospace scientist, and his son Steven set to work on flywheels.
In 1990, they founded American Flywheel Systems. Mr. Bitterly, a former engineer with the National Aeronautics and Space Administration, created balancing techniques for high-velocity spinning masses used in developing the space shuttle. He envisioned three main flywheel developments. The first was to increase the structural integrity of the flywheel’s rim, which is reinforced with carbon-composite fibers, through a special filament winding technique.
He then developed spoke-like connectors that could expand with the rim at high speeds and still provide overall stability. The third idea was an efficient means of spinning the rim to store energy and of extracting useful power while slowing it down. The Bitterlys built the rims and tested them to destruction.
They discovered that when a flywheel made of composite fibers broke apart, it produced a fluff of “cotton candy” material rather than the high-velocity shrapnel that steel flywheels produced when they disintegrated. Seeking Support Edward W. Furia, the president of American Flywheel and a former official of the Environmental Protection Agency, has found some backing from a Dutch bank and is also seeking support from auto makers and the Federal Government.
He is seeking $10 million to build a prototype, which he says can be ready in 12 months, with a production model to follow in another 12 months. He said economies of scale achieved by mass production would bring the price of the flywheel device near to that of a gasoline engine.
How do rotating wheels generate electricity?
How Spinning Creates Electricity – Today’s generators work on the same principles of electromagnetic induction that were discovered in 1832. In this year, a man named Michael Faraday discovered that electrical charges could be created when an electrical conductor was moved in a magnetic field.
Can I connect a wind turbine to my solar system?
Can you charge with solar and wind at the same time? – Yes! Running through a hybrid charge controller allows you to use both solar panels and wind turbines to charge your battery bank, presuming both are receiving enough sun or wind to generate electricity.
Can I use solar inverter for wind turbine?
Can I Connect A Wind Turbine To My Solar Inverter? – Yes. You can connect the solar panel system and wind turbine with the help of a professional. Also, you should check whether the wind turbine gives DC and has the correct voltage. If the output is not DC or the voltage is not right, you should not connect the wind turbine to your solar inverter,
Can we use solar inverter for wind turbine?
Do you want to install a wind generator to get free power after the sun goes down? – First, these are essential:
- There must be sufficient, clean, consistent (no eddies) wind where the wind generator is to be located.
- There must be at least 10 metres distance to the closest building, tree, hill, or anything else that could affect the wind.
- The project must comply with all local Council regulations. (This may include restrictions on height, visual appearance, noise, or even the neighbours not liking it.)
- Our wind generators are regulated by a low voltage (48v) battery, and batteries must be installed in a safe location where they cannot cause injury, damage, or fire.
- Some existing solar battery systems combine perfectly with our wind generators, and others do not. Call us for details.
- If you are considering upgrading an existing solar power system, include a hybrid (low-voltage) solar inverter that will likely allow easy connection to a wind generator.
There are four main areas from which we receive most of our enquiries: 1. Add a wind generator to an existing solar power system 2. Install a wind generator to a hybrid solar system with a 48-volt battery 3. Add a wind generator to solar power with a high-voltage (eg Tesla) battery 4. Connect a wind generator to an off-grid solar power system
Can I use a solar charge controller for a wind turbine?
A solar charge controller cannot be used for a wind turbine. Although both solar and wind charge controllers protect the battery from overcharging, they are very different. A wind charge controller needs to dump its excess load while a solar charge controller does not.