Archive for the 'Wind Power Energy' Category
Last night’s guest on the Daily Show was a 22-year-old man from a small village in Africa. Due to famine in his country, the young man was forced to drop out of school to help support his family. His village maintained a small library, where he would go to study anything he could find, including physics and engineering.
Although his understanding of English was rudimentary, he studied various energy concepts, including how wind power works. Then just 14-years-old, he constructed an energy producing windmill from wood and other basic supplies for his family simply by studying figures and diagrams in the texts. We could use ingenuity and work ethic like that from children in our schools.
Here are the most frequently unknown or misunderstood facts about industrial wind power.
How big are the towers?
Industrial wind turbines are not the benign little structures you might see in a schoolyard or behind someone’s house.
The widespread GE 1.5-megawatt model, for example, consists of 116-ft blades atop a 212-ft tower for a total height of 328 feet. The blades sweep an area just under an acre. The 1.8-megawatt Vestas V90 from Denmark is also common. Its 148-ft blades (sweeping more than 1.5 acres) are on a 262-ft tower, totaling 410 feet. Also gaining use in the U.S. is the 2-megawatt Gamesa G87 from Spain, which sports 143-ft blades (just under 1.5 acres) on a 256-ft tower, totaling 399 feet.
Many existing models and new ones now coming out reach well over 400 feet high, with higher towers and extra-long blades designed to turn the generator in less-than-ideal sites.
The base of the steel tower is anchored in a platform of more than a thousand tons of cement and steel rebar, 30 to 50 feet across and anywhere from 6 to 30 feet deep. Pylons may be driven down farther to help anchor the platform.
The gearbox — which transforms the slow turning of the blades to a faster rotor speed — and the generator are massive pieces of machinery housed in a bus-sized container, called the nacelle, at the top of the tower. The blades are attached to the rotor hub at one end of the nacelle. Some nacelles include a helicopter landing pad.
On the GE 1.5-megawatt model, the nacelle alone weighs more than 56 tons, the blade assembly weighs more than 36 tons, and the tower itself weighs about 71 tons, for a total weight of 164 tons. The corresponding weights for the Vestas V90 are 75, 40, and 152, total 267 tons, and for the Gamesa G87 72, 42, and 220, total 334 tons.
Besides the noise and vibrations such huge moving machines unavoidably generate, they must be topped with flashing lights day and night to increase their visibility.
These issues and benefits are based on the use of large industrial Turbines, as the ones we see on the hilltops in the picture. When we build home made wind power for our own home use, most of the downsides are gone, as they are quiet and quite unobtrusive. Or we can purchase ready made and fun to look at.
Updated: Thu Sep. 24 2009 12:22:29 PM
The Canadian Press
Toronto — New industrial wind turbines in Ontario will have to be at least 550 metres away from the nearest homes under new regulations announced today.
The restrictions apply to projects with only five wind turbines or less, and the residential setbacks will increase with the number and sound level of additional turbines.
The regulations for the province’s Green Energy Act will also prohibit large-scale solar panel projects from prime agricultural lands.
Premier Dalton McGuinty announced the feed-in-tariff — the amount paid to producers of renewable energy — will range from 10.3 cents per kilowatt hour to 80.2 cents.
The feed-in-tariff is designed to encourage large and small scale energy production, with the highest rate reserved for residential solar rooftop projects of 10 kilowatts or less.
There will also be what the government calls a “price adder” to encourage aboriginal communities to develop alternative energy supplies and sell any excess power back to the grid.
Energy from Moving Air
How Uneven Heating of Water and Land Causes Wind
Wind is simply air in motion. It is caused by the uneven heating of the Earth’s surface by the sun. Because the Earth’s surface is made of very different types of land and water, it absorbs the sun’s heat at different rates.
The Daily Wind Cycle
During the day, the air above the land heats up more quickly than the air over water. The warm air over the land expands and rises, and the heavier, cooler air rushes in to take its place, creating wind. At night, the winds are reversed because the air cools more rapidly over land than over water If you were to have made a wind generator, with all the easy instructions and videos on home made wind power you too could be saving and watching how the wind involves your own property.
In the same way, the atmospheric winds that circle the earth are created because the land near the Earth’s equator is heated more by the sun than the land near the North and South Poles.
Wind Energy for Electricity Generation
Today, wind energy is mainly used to generate electricity. Wind is a renewable energy source because the wind will blow as long as the sun shines.
If you live in a windy area, chances are you’ve noticed some gigantic pieces of machinery dotting the hillside. Wind Turbines with wind renewable energy, collect energy from powerful air currents, much like windmills. The difference lies in the fact that turbines generate mechanical energy, while windmills merely grind grain.
Wind energy is actually generated for a profit on wind farms across the country. The turbines on these farms are connected to a centralized power collection network, and the energy is eventually disseminated at a cost to consumers. Many wind farms support various forms of agriculture, as turbines do nothing to interfere with crop growth.