Tuesday, November 3, 2009

RENEWABLE ENERGY














SOLAR ENERGY

Solar energy, radiant light and heat from the Sun, has been harnessed by humans since ancient times using a range of ever-evolving technologies. Solar radiation, along with secondary solar-powered resources such as wind and wave power, hydroelectricity and biomass, account for most of the available renewable energy on Earth. Only a minuscule fraction of the available solar energy is used.















WATER POWER

Hydropower, hydraulic power or water power is power that is derived from the force or energy of moving water, which may be harnessed for useful purposes.

Prior to the widespread availability of commercial electric power, hydropower was used for irrigation, and operation of various machines, such as watermills, textile machines, sawmills, dock cranes, and domestic lifts.

Another method used a trompe, which produces compressed air from falling water, which could then be used to power other machinery at a distance from the water.























GEOTHERMAL ENERGY

Geothermal power (from the Greek roots geo, meaning earth, and thermos, meaning heat) is power extracted from heat stored in the earth. This geothermal energy originates from the original formation of the planet, from radioactive decay of minerals, and from solar energy absorbed at the surface. It has been used for bathing since paleolithic times and for space heating since ancient roman times, but is now better known for generating electricity. Worldwide, geothermal plants have the capacity to generate about 10 gigawatts of electricity as of 2007, and in practice supply 0.3% of global electricity demand. An additional 28 gigawatts of direct geothermal heating capacity is installed for district heating, space heating, spas, industrial processes, desalination and agricultural applications.






















WIND POWER

Wind power is the conversion of wind energy into a useful form of energy, such as electricity, using wind turbines. At the end of 2008, worldwide nameplate capacity of wind-powered generators was 121.2 gigawatts (GW).[1] In 2008, wind power produced about 1.5% of worldwide electricity usage;[1][2] and is growing rapidly, having doubled in the three years between 2005 and 2008. Several countries have achieved relatively high levels of wind power penetration, such as 19% of stationary electricity production in Denmark, 11% in Spain and Portugal, and 7% in Germany and the Republic of Ireland in 2008. As of May 2009, eighty countries around the world are using wind power on a commercial basis.[2]

Large-scale wind farms are connected to the electric power transmission network; smaller facilities are used to provide electricity to isolated locations. Utility companies increasingly buy back surplus electricity produced by small domestic turbines. Wind energy as a power source is attractive as an alternative to fossil fuels, because it is plentiful, renewable, widely distributed, clean, and produces no greenhouse gas emissions. However, the construction of wind farms is not universally welcomed because of their visual impact and other effects on the environment.

Wind power is non-dispatchable, meaning that for economic operation, all of the available output must be taken when it is available. Other resources, such as hydropower, and standard load management techniques must be used to match supply with demand. The intermittency of wind seldom creates problems when using wind power to supply a low proportion of total demand. Where wind is to be used for a moderate fraction of demand such as 40%, additional costs for compensation of intermittency are considered to be modest.[3][4]















BIOFUEL

Biofuelsliquid fuels derived from plant materials – are entering the market, driven by factors such as oil price spikes and the need for increased energy security.

Bioethanol is an alcohol made by fermenting the sugar components of plant materials and it is made mostly from sugar and starch crops. With advanced technology being developed, cellulosic biomass, such as trees and grasses, are also used as feedstocks for ethanol production. Ethanol can be used as a fuel for vehicles in its pure form, but it is usually used as a gasoline additive to increase octane and improve vehicle emissions. Bioethanol is widely used in the USA and Brazil.

Biodiesel is made from vegetable oils, animal fats or recycled greases. Biodiesel can be used as a fuel for vehicles in its pure form, but it is usually used as a diesel additive to reduce levels of particulates, carbon monoxide, and hydrocarbons from diesel-powered vehicles. Biodiesel is produced from oils or fats using transesterification and is the most common biofuel in Europe.

Biofuels provided 1.8% of the world’s transport fuel in 2008. Investment into biofuels production capacity exceeded $4 billion worldwide in 2007 and is growing.[1]

Tuesday, October 20, 2009

THINGS TO DO DURING TYPHOON
















1. Complete all precautions in your home. Lock all windows and doors, fit bars into position and insert reinforced shutters and gates if they are available. Adhesive tape fixed to large window-panes in exposed positions will reduce damage by broken glass. Storm water drains should be cleared of leaves and rubbish.

2. Since seas are rough, you are advised to stay away from the shoreline and not to engage in water sports.

3. Flights at Hong Kong International Airport may be affected by the weather. Please contact your airline for the latest flight information before departing for the airport.

4. Please listen to your radio or watch your TV for the latest weather information broadcast at the 15th, 30th, 45th and 58th minute of each hour. You can also browse the Hong Kong Observatory's web site for the information."


Tuesday, October 6, 2009

THINGS YOU CAN DO HELP SAVE FOREST


The most common way of saving the forest,is to plant more trees.

WHY FORESTS ARE IMPORTANT?
























How is a forest ecosystem important to the environment as a whole?

The world's forests have many values. They are home to more than half of all species living on land. Forests also help to slow global warming. Trees help by taking carbon dioxide from the air and storing it as carbon in their wood. They reduce the greenhouse effect. Even after the trees are cut down and used as lumber, the wood continues to store carbon and keep it out of the atmosphere.

Forests help regulate local and regional rainfall. Additionally, forests provide crucial sources of food, medicine, clean drinking water, and immense recreational, aesthetic, and spiritual benefits for millions of people.

Forests are sources of wood products. In many parts of the world, forests are being rapidly cleared for agriculture or pasture, destructively logged and mined, and degraded by human-set fires. The burning of trees releases the stored carbon back into the atmosphere. Together, these activities contribute about 25 percent of annual human-caused emissions of carbon dioxide - the principal greenhouse gas - and drive the decline and extinction of forest species.

WHY FORESTS ARE IMPORTANT?






















How is a forest ecosystem important to the environment as a whole?

The world's forests have many values. They are home to more than half of all species living on land. Forests also help to slow global warming. Trees help by taking carbon dioxide from the air and storing it as carbon in their wood. They reduce the greenhouse effect. Even after the trees are cut down and used as lumber, the wood continues to store carbon and keep it out of the atmosphere.

Forests help regulate local and regional rainfall. Additionally, forests provide crucial sources of food, medicine, clean drinking water, and immense recreational, aesthetic, and spiritual benefits for millions of people.

Forests are sources of wood products. In many parts of the world, forests are being rapidly cleared for agriculture or pasture, destructively logged and mined, and degraded by human-set fires. The burning of trees releases the stored carbon back into the atmosphere. Together, these activities contribute about 25 percent of annual human-caused emissions of carbon dioxide - the principal greenhouse gas - and drive the decline and extinction of forest species.

Thursday, August 13, 2009

Tuesday, August 11, 2009

Ways to Prevent Air Pollution


Stop smoking it causes Respiratory Disease. It can also damage the the O-Zone Layer and causes air pollution. It also causes Global Warming. That makes the Earth hotter and hotter each day. That makes the plants (that give oxygen) to be rotten. Use bike instead of cars that contributes Air Pollution and Global Warming. It can also help your body to secretes sweat. Don't burn plastics. It can be recycle. It can help you save money.