Wind Turbine Generators

 Wind Turbine Generators - Free power from mother nature. Maybe we could install it now.!!

Wind generators are one of the most reliable forms of alternative power sources on the planet.  They are made to manufacture power by transforming the kinetic energy of the wind into mechanical energy, which is then either harnessed directly (in the case of windmills, for example, which were used to change wheat into flour, or to pump water for farming) or coupled to a generator that creates a DC output that can be used in a more general sense.  In this article I will be talking about the type of wind generators that produce electric energy, as this is more useful to us in our daily lives.

Wind turbines are basically large windmills, with gigantic blades that rotate in the wind and produce power from the conversion of the winds force.  Wind turbines are manufactured from plastic, aluminium, steel and numerous other space age metals.

Wind turbines have a few negative impacts on the environment.  They are very visible, and quite unsightly since they must be put in proximity to windy, open terrain to be useful - attempts to locate them off the coast have been met with great success.  They require a great deal of energy in their manufacture, energy which is typically fossil-based, and therefore it can take a considerable amount of time before they are positive in terms of total carbon emissions - this time can be anywhere from 2 to 5 years.  Wind turbines are linked to the mauling of rare species of birds that can be mutilated as they pass through the turbine fans during migratory passages.

With all of the downsides aside, wind turbines should be a choice when talking about a broad plan for renewable energy.  Once erected, wind turbines are amazingly efficient in a larger sense - they generate power from a natural, eco-friendly renewable resource, without the hidden social or environmental penalties that we incur with the use of fossil fuels - theres no need to mine for fuel or to transport it - there are no global warming pollutants created, and no need to store, process, or to dispose of toxic wastes.

At the small side of the scale, turbines can be as tiny as 5 feet in diameter and are capable of only a few hundred watts.  On the high end of the spectrum, turbines can be as huge as three hundred feet in diameter and are capable of generating two to five megawatts of power.

Similar to photovoltaic solar power generation, there might be rebates available for construction, and excess energy can be sold back to the power company.

Wind velocity is impacted by topography and increases with height above the ground, so wind turbines are generally installed on top of large towers.  In a typical application, the wind turbine sits on top of a tall  tower and generates low voltage DC which is used to charge a battery store - this stored potential energy is ultimately utilized by routing it through an inverter that changes the low voltage direct current power into utility voltage alternating current electricity that can be used in household applications.  By concentrating a lot of turbines into wind farms a substantial amount of electricity can be stored and utilized, perhaps for a whole city or town.

Because the wind doesnt blow all of the time in many areas, wind turbines are used as adjuncts in hybrid configurations with many different technologies like photovoltaic panels, and diesel generators to provide a consistent source of electricity.

Dissimilar to fossil-fuel stations, wind turbines are clean and green - they dont create the carbon dioxide emissions that are causing greenhouse gases or the SO2 emissions that cause acid rain.

Todays turbines are divided into 2 categories, namely horizontal turbines and vertica turbines.  Todays horizontal axis wind turbines are actually far better at capturing the wind than vertical axis turbines given the same amount of swept area (which is the diameter of the circle traced by the outside tip of the rotor blades).

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Sleeping Bag Ratings - A New Idea

It seems that sleeping bag ratings have no consistency. Temperature ratings are still determined entirely by the manufacturers of the bags. My 3-pound Sierra Designs bag, for example, was rated to 20 degrees. Honestly, it never kept me as warm as my 17-ounce Western Mountaineering sleeping bag, which is only rated down to 40 degrees. Isn't this a problem when you buy a bag? Maybe a 45-degree bag will keep you warmer than a 30-degree bag. Consistent Sleeping Bag Ratings No matter what temperature a bag is rated for, under any system of testing, it won't necessarily keep you warm to that temperature. We can't solve the problem of people having different metabolisms and bodies. A particular bag might be good for one person down to 20 degrees, while for another it is only good to 40 degrees. You generally can figure out if you are a cold or a warm sleeper, but that doesn't help if you don't know whether a bag is rated too high or too low. You need to know that if a bag says 30 degrees it will keep you warmer than one that says 40 degrees. With that, even if you add or subtract 10 or 20 degrees for your personal tastes, you can still figure out which bag is the warmer one. How do we get this consistency? Begin testing with any sleeping bag, by putting a bag of water in it that is human-sized, weighing perhaps 160 pounds. Have three standard sizes for small, regular and large sleeping bags. Always start with the water temperature at 100 degrees Fahrenheit, and measure how long before it drops to 90 degrees. External air temperature has to always be the same too, whther it is 60 degrees or 40. The numbers are not crucial. What's important here is that once the standards are chosen, every bag is tested the same way, with the same conditions (even the temperature and material of the testing platform would have to be the same). This is what will give consistency to the sleeping bag ratings for warmth. Now, if a bag rated to 40 degrees keeps the water above 90 for two hours, a bag rated for 30 would obviously have to keep it above 90 degrees for a longer time. Pegging heat-retention times to specific temperature ratings would be a bit tricky at first. However, once done, each new bag on the market could be submitted to the testing and quickly given a consistent rating. We would know that a lower rating would always mean a warmer bag, degree-by-degree. We could even have old bags tested to see if it is time to replace them. Manufacturer Acceptance? Would manufacturers pay a private testing company to have their bags rated? Some, at first, because it would be a an advantage for those companies who are already conservative in their temperature ratings. They would have "proof" that the bags are even warmer than they were claiming. Then, eventually, all bag makers would feel some motivation to have their sleeping bags tested, because consumers would be wary about buying ones that weren't tested. I hope someone will take this idea and run with it. An existing consumer rating company, like Consumer Reports, could do this on their own and report the results. Even if they listed the bags without temperature ratings, but in absolute order by which held the heat in the best, it would be very useful. One could look at the list and if their current bag kept them warm to 25 degrees, ythey would know that any bag higher on the list would be warmer. Isn't it time for consistent sleeping bag ratings?

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Tea: Origins, Flavors and Health Benefits

How many times do we just want to drink tea after a heavy meal, but are then bombarded with all the various tea flavours that we get lost. This article answers that need.

What you should always remember is that there are only four types of tea.
1) Black tea
2) Green tea
3) White tea
4) Oolong tea

All these are made from the leaves of the Camellia sinensis, also known as the tea plant. Other herbal infusions such as chamomile tea, ginger tea or red tea made of rooibos leaves are disqualified as types of tea since the tea plant is not involved in their making. The difference between the four tea variations lies in the process of making them. In addition, each type of tea has another flavor and various health benefits.

1) Black Tea
The strong flavored burnt Sienna colored hot beverage is the most popular type of tea in the West. Either served with a squeeze of lemon or added milk and a cube of sugar, the cup of black tea is part of daily tea ceremonies that take place worldwide. Black tea is made of heavily oxidized Camellia sinensis leaves. When served plain, it contains no calories, carbohydrates, or fats. A cup of black tea contains more caffeine than any other types of tea but less than in any cup of coffee.

2) Green Tea
The lightly oxidized tea has been popular in China, Japan and Korea for centuries. Recently, rumors on its health benefits increased its popularity in the West as well. It has been proven that drinking green tea can lower cholesterol, prevent cancer, increase metabolic rates and be helpful in variety of other conditions and illnesses. The green tea is lightly oxidized, dried, but not fermented. It is usually served plain, without sugar or milk. Since some of the green tea variants taste a bit bitter, it should be brewed in lower temperature than the boiling point.

3) White Tea
White tea is rarer and more expensive than the other types of teas mentioned above. Originated in the Fujian province of china, the white tea is made of young Camellia sinensis leaves, which go through a long process of steaming or frying, inactivate fermenting and drying. Since the leaves are harvested while the buds are still covered by white hair, it is called white tea. White tea has the most delicate, sweet taste than the other types of tea. Moreover, it contains the smallest amount of caffeine and the largest amount of antioxidant that help prevent cancer.

4) Oolong Tea
The traditional Chinese tea is the common companion of Chinese foods such as dim sum and chop suey in American Chinese restaurants. The oolong tea, black dragon in Chinese, got its name after its long, dark distinguished leaves that look like wild black dragons when brewed. The unique taste of the oolong tea is achieved by a long process that includes sun drying of the Camellia sinensis leaves, light oxidization, cooling and drying processes. The result is a lighter flavor than the popular black tea and stronger than the delicate green tea.

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