Sound energy

Fossil fuel

Wind energy

Sound energy

• Sound energy is the energy produced by sound vibrations as they travel through a specific medium.

• Sound vibrations cause waves of pressure

which lead to some level of compression and rarefaction in the mediums through which the sound waves travel.

• Sound energy is, therefore, a form of mechanical energy; it is not contained in discrete particles and is not related to any chemical change, but is purely related to the pressure its vibrations cause.

• Sound energy is typically not used for electrical power or for other human energy needs because the amount of energy that can be gained from sound is quite small.

Fossil fuelsEnergy from fossilised organic

materials

• The fossil fuels are coal, oil and natural gas.

• They are fuels because they release heat energy when they are burned.

• They are fossil fuels because they were formed from the remains of living organisms millions of years ago.

• fossil fuels provided around 66% of the world's electrical power, and 95% of the world's total energy demands (including heating, transport, electricity generation and other uses).

Coal• Coal provides around 28% of our energy.• Burning coal produces sulphur dioxide, an acidic

gas that contributes to the formation of acid rain. This can be largely avoided using "flue gas desulphurisation" to clean up the gases before they are released into the atmosphere. This method uses limestone, and produces gypsum for the building industry as a by-product. However, it uses a lot of limestone.

Crude oil• Liquid fossil fuels, like petroleum, is

formed in areas that covered by oceans or seas.

• formed when dead plants and animals sank to the bottom of the ocean and were covered by sediments.

• Over millions of years, pressure, bacterial processes, and heat changed the sediments into sedimentary rocks and the plant and animal remains into oil.

• Eventually underground pools of oil formed when oil migrated through the pores and cracks of rocks and eventually filled these empty spaces.

Natural gas • It is found sometimes with

petroleum, with coal, or by itself. • less dense, it is most often found

on top of oil pools. • valuable because it burns cleanly,

releases energy, and can be easily transported in underground pipelines.

• We use natural gas in many ways including heating our homes and cooking our food

How fossil fuels produce ENERGY

Advantages • Very large amounts of electricity can be generated in one

place using coal, fairly cheaply.

• Transporting oil and gas to the power stations is easy.

• Gas-fired power stations are very efficient.

• A fossil-fuelled power station can be built almost anywhere, so long as you can get large quantities of fuel to it.

Disadvantages • Fossil fuels are non-renewable energy resources.

• Fossil fuels release carbon dioxide when they burn, which adds to the greenhouse effect and increases global warming.

• Coal and oil release sulfur dioxide gas when they burn, which causes breathing problems for living creatures and contributes to acid rain.

Is it renewable?

• Fossil fuels are not a renewable energy resource.

Once we've burned them all, there isn't any more, and our consumption of fossil fuels has nearly doubled every 20 years since 1900.

Wind Energy

• Wind energy is -- ENERGY obtained from moving air.-- The motion results from the heating and

cooling of the Earth.-- Renewable resource.

Wind power is the conversion of wind energy into a useful form of energy, etc:

wind turbines to make electricity,

wind mills for mechanical power,

wind pumps for pumping water or drainage, or sails to propel ships

Advantages

• inexhaustible energy source

• no fuel cost

Disadvantages

• wind conditions are unpredictable:

they are subject to gusting and becalming, to daily and seasonal variations in strength, and to interactions with local topographic features.

References:

• Sound energy. http://www.wisegeek.com/what-is-sound-energy.htm. Accessed on 3 Jan 2011

• Fossil Fuels. http://www.darvill.clara.net/altenerg/fossil.htm. Accessed on 3 Jan 2011

• Wind power. en.wikipedia.org/wiki/Wind_power. Accessed on 3 Jan 2011

THANK YOU!