Archive | August 2015

How Wind Turbines Operate?

In contrast to the windmills common in the nineteenth century, a modern power generating

wind turbine is designed to produce high quality, network frequency electricity whenever enough wind is available. Wind turbines can operate continuously, unattended and with low maintenance with some 120,000 hours of active operation in a design life of 20 years. By comparison, a typical car engine has a design lifetime of the order of 6,000 hours.

The rotors of modern wind turbines generally consist of three blades, with their speed and power controlled by either stall or pitch regulation. Stall regulation involves controlling the mechanical rotation of the blades, pitch regulation (now more commonly used) involves changing the angle of the blades themselves. Rotor blades are manufactured from composite materials using fibreglass and polyester or fibreglass and epoxy, sometimes in combination with wood and carbon.

Energy captured by the steadily rotating blades is transferred to an electrical generator via a gearbox and drive train. Alternatively, the generator can be coupled directly to the rotor in a direct drive`s arrangement. Turbines able to operate at varying speeds are increasingly common, a characteristic which improves compatibility with

the electricity grid. The gearbox, generator and other control equipment are housed within a protective nacelle.

Tubular towers supporting the nacelle and rotor are usually made of steel, and taper from their base to the top. The entire nacelle and rotor are designed to move round, or yaw, in order to face the prevailing wind.

Wind resources and monitoring

The wind resource is the fuel for a wind power station, and just small changes have large impact on the commercial value of a farm. Every time the average wind speed doubles, the

power in the wind increases by a factor of eight, so even small changes in average speed can produce large changes in performance. If the average wind speed at a given site increases from 6 metres per second (m/s) to 10 m/s, for example, the amount of energy produced by a wind farm will increase by over 130%. Detailed and reliable information about how strongly, from which direction and how regularly the wind blows, is therefore vital for any prospective development.

At a national and regional level, European wind atlases have been produced which record the wind speed to be expected in particular areas. For specific sites, more detailed assessment is required using data from nearby weather stations and specialist computer software to model the wind resource. Finally, site specific measurements are carried out using an anemometry mast on which a number of anemometers measure the wind speed and direction at different heights above ground.

Overall, the exploitable onshore wind resource for the European Union (EU-25) is conservatively estimated to be capable of generating an output of 600 Terawatt hours (TWh). The wind resource in offshore waters has been assessed at up to 3,000 TWh. This alone would exceed Europe`s entire current electricity consumption.

Wind farms

A number of constraints affect the siting of a cluster of wind turbines, usually described as a

wind farm or park. These include land ownership, positioning in relation to buildings and roads, and avoidance of sites of special environmental importance. Once these constraints have been determined, the layout of the wind turbines themselves can be planned. The overall aim is to maximise electricity production whilst minimizing infrastructure, operation and maintenance (O&M) costs, and environmental impacts. Specialist software has been developed to produce visualizations of how the turbines will appear in the landscape, enabling developers and planners to choose the best visual impact solutions before the project is constructed.

Apart from the turbines themselves, the other principal components of a wind farm are the foundations to support the turbine towers, access roads and the infrastructure to export the electrical output to the grid network. A 10 MW wind farm can easily be constructed within two months, producing enough power to meet the consumption of over 5,000 average European households.

Once operating, a wind farm can be monitored and controlled remotely. A mobile

team carries out maintenance work, with roughly two personnel for every 20 to 30 turbines. Typical maintenance time for a modern wind turbine is about 40 hours per year. Wind farms can vary in size from a few megawatts up to the largest so far – 300 MW in the western United States.

The advantages of wind power

� Low cost can be competitive with nuclear, coal and gas on a level

� playing field

� The fuel is free, abundant and inexhaustible

� Clean energy – no resulting carbon dioxide emissions

� Provides a hedge against fuel price volatility

� Security of supply – avoids reliance on imported fuels

� Modular and rapid to install

� Provides bulk power equivalent to conventional sources

� Land friendly – agricultural/industrial activity can continue around it.

Solar Energy – To Supply the Needed Power

The world is currently suffering from energy and fuel crisis. Fossil fuels are incessantly depleting and so energy bills are soaring higher and higher. Many homeowners and establishments are now complaining about their huge expenses. But did you know that there is an answer to the crisis and it has long been available to man. However, because of its inefficiency, it is not recognized as a viable solution. Solar energy is free but the cost of generating it is a bit expensive. With the vast improvements in technology, there are now more affordable options for those who want to use solar energy to supply power in their homes and offices.

Today, you can find a lot of manufacturers that market solar power kits. How effective are these power kits anyway? Many households are now utilizing the kits because they are efficient and convenient in generating the needed power from sunlight.

Battery chargers that are powered by solar energy are now widely available. Now, you don’t need to rely fully on conventional electricity to power electrical devices. If you install the right size solar panel, you may be able to decrease your dependence on conventional energy sources. The energy from the sun is free and you will simply need to invest on the kit for a good power system.

People usually think that without sunlight, power can’t be generated. The power kits are not only designed to capture the sun’s energy but also to store the energy as well. During sunny weather, energy from the sun is converted into electricity and those that are not consumed will be stored. The stored energy can now be used at night or during unpleasant weather.

With portable chargers, you won’t be able to get enough power. You can only use them for recharging small electric devices and batter packs. Cellular phones can be charged using the portable solar power chargers. The power is easily drained out and so it’s not a very efficient source of energy. Despite the shortcomings of these devices, it would help if you still have them around. Who knows… a few years from now, researchers and scientists may be able to make a major breakthrough in solar power.

Since the power kits are affordable, a lot of people are now using them. A solar panel usually has one charger where you will plug the equipment. The solar chargers are very useful and you can carry them even in your hiking trips. Just place them on your car’s dashboard where sunlight is accessible.

The portable chargers or solar panels can be mounted in the rooftop to get a lot of sunlight. The large panels are still expensive and not many people can afford to buy one. However, governments can subsidize the investment to set up the power system. If you live in a place where the government offers subsidies, grants, and loans for the use of solar power, you’re quite lucky. Take advantage of it so that you can now use free energy. Tax incentives are even offered in some places to encourage residents to go for solar power.

If you’re still not sure about the efficiency of solar power, you can start by using a power kit. You can get the kit for as low as $200 to $300. Try it now and expand the system later on.

The Future of Limitless Energy : Documentary on the Future Technologies of Sustainable Energy

Wind Energy – The Pros And Cons

Don Quijote might have difficulty tilting at the huge, modern windmills responsible for harnessing wind energy and converting it into electricity. And, present-day windmills certainly aren`t as appealing to the eye as the picturesque, black-and-white structures of Cervante`s day.

But, unappealing as they may look, they are, in fact, the fastest-growing form of energy generators in the World, and help resolve one of mankind`s most serious problems: that of finding environmentally-friendly and renewable fuel sources to meet our increasingly high energy demands.

So, let`s take a closer look at wind power and its advantages, plus any disadvantages it may have.

Advantages

1. Clean and Renewable. The fossil fuels of coal, oil and gas harm our environment by contributing carbon dioxide to the atmosphere. They are also unsustainable, meaning that they`ll run out one day. Wind, on the other hand, will always be around, and it won`t pollute the atmosphere.

2. Cost Effective. Energy created by wind turbines used to cost more than that created by fossil fuels. But, larger blades have cut the costs, making them equal to fossil fuels. What`s more, as technology advances, costs should be even further reduced.

3. Quick To Set Up. Once a suitable site has been chosen and the appropriate permission granted, wind farms take very little time to actually build.

4. Land Still Usable. The land surrounding the wind turbines can also be used for other purposes, such as agriculture.

However, as with everything, drawbacks always exist.

Disadvantages

1. Unsightly. Most people would agree that the idea of using wind power is a good one. But, in practise, very few want these large, unappealing constructions in their vicinity.

2. Noisy. The turbine blades also make quite a lot of noise.

3. Harmful To Wildlife. Wind turbines can be hazardous to creatures that fly, such as birds.

Although there are drawbacks, remedies for them are constantly being studied, improvements made, and new blades invented to render the process more cost-effective.

The World is in desperate need of good alternative sources of power, to enable us to end our long-standing dependence on fossil fuels. Wind energy is an excellent option.