222
 
   
   
clemens clemens clemens
Referat

TitelAlternative Energy 
Anzahl Worte1542 
SpracheEnglisch 
ArtReferat 
SchlagworteEfficiency, Solar power, Enironmental factors, conventional energy sources, 
Downloads++ 
Bewertungnicht bewertet 

Download Zip (179kB)
Download Pdf (35.7kB)


Auszug aus dem Referat (ohne Grafiken)

ALTERNATIVE ENERGY



Table of contents



1 What is alternative energy?


2 Electricity and the environment: Why should we care?

2.1 Environmental factors

2.2 Conventional energy sources


3 Alternative technologies

3.1 Efficiency

3.2 Solar power

3.2.1 Solar thermal power

3.2.2 Photovoltaic cells

3.3 Geothermal power

3.4 Wind power

3.5 Low impact hydro power

3.6 Biomass power


4 Pros and cons


5 Words


6 Sources








1 What is alternative energy?


Originaldokument enthält an dieser Stelle eine Grafik!
Original document contains a graphic at this position!

Alternative power, or alternative energy is electricity that is produced in a clean way by using environmentally friendly basic material or sources.
The basic materials could be renewable ones, like biomass or natural gas.
Alternative sources are more or less powered from the sun. For example solar energy, wind energy and all kinds of hydro power. Some others, like geothermal, are powered from the geothermal heat beneath the earth´s surface.
The target is to minimize all kinds of pollution. But it is not so easy to force alternative energy. As long as commercial power sources (coal, oil, nuclear, hi-impact hydro) are cheaper than alternative energy, people will use comercial sources. Both new techniques have to be developed and environmental factors have to be right to keep the price low. For example, geothermal power could be used almost anywhere at Iceland, but hardly in Austria.


2 Electricity and the environment: Why should we care?


Originaldokument enthält an dieser Stelle eine Grafik!
Original document contains a graphic at this position!

Today, the electric power system is the largest single source of industrial air pollution, besides traffic. Conventional sources of electricity harm human health, destroy ecosystems, add to global warming and have high economic costs. Air pollutants are the major cause of asthma attacks to children and grown ups. Billions of liters of water are used to condense overheated steam in thermal power plants. This heated water can devastate fish population and coral reefs. Like el-nino is warming up the sea, which is caused by the greenhouse effect. Smog, acid rain and heavy metals harm the health of people all over the world. Climatic changes and environmental damage are serious indicators that the status quo is unacceptable.


Originaldokument enthält an dieser Stelle eine Grafik!
Original document contains a graphic at this position!


Originaldokument enthält an dieser Stelle eine Grafik!
Original document contains a graphic at this position!


Originaldokument enthält an dieser Stelle eine Grafik!
Original document contains a graphic at this position!


Originaldokument enthält an dieser Stelle eine Grafik!
Original document contains a graphic at this position!



Oil, coal or other petroleum-based recources are called fossil fuels. They are formed by the decayed remains of prehistoric plants and animals. Burning these fuels creates greenhouse gases that accumulate in the atmosphere and allow high level ultraviolet radiation to pass through. Also sulfur dioxide, nitrogen oxide and carbon oxide are released.

High impact hydro-electric plants damage their surrounding area with their big dams. Also natural river flows are changed and fish populations are killed.

Nuclear energy is produced by causing changes in the nucleus of the atom. There is no air pollution but nuclear plants create dangerous radioactive wastes. They are difficult to dispose and last for centuries.
There are no permanent storage sites for this kind of waste.


3 Alternative technologies


Originaldokument enthält an dieser Stelle eine Grafik!
Original document contains a graphic at this position!

Efficiency is the cleanest “source”. Using energy saving services lessens the demand for electricity.
Buying economical household appliances and low fuel cars help to keep the environment clean.

Originaldokument enthält an dieser Stelle eine Grafik!
Original document contains a graphic at this position!

The sun´s radiation is used directly to produce energy, which could be produced in two ways. Solar thermal and photovoltaic systems. Solar thermal systems use the sun´s energy to heat water or transform it into steam. Heated water is used to heat for example a swimmingpool. The steam is used to turn a turbine and a generator, which produce the electric energy.
Photovoltaic panels, commonly called solar cells or modules, use semiconductor materials to convert sunlight direct into electricity. These panels are used in remote areas. It is cheaper than stringing miles of electrical wire. The price of solar energy, which was once very high, has dropped by half every five years over the last 25 years.

Originaldokument enthält an dieser Stelle eine Grafik!
Original document contains a graphic at this position!

Windmills or turbines are used to produce electricity. Wind power emits no pollution. If care is taken to avoid placing the windmills in undeveloped areas, these generators can have relative little impact on the land. Using wind is economical in areas where the average wind speed is at least 20 kilometers per hour. Although a single wind turbine can produce a usable amount of electricity, most wind power is produced in wind farms. These are large groups of turbines grouped together on a site. Wind power is one of the cleanest sources that can be used. And the cost- power relation is better than for example for solar power.

Originaldokument enthält an dieser Stelle eine Grafik!
Original document contains a graphic at this position!

The geothermal heat in deep areas beneath the earth´s surface is used to produce overheated steam. This steam can be used to produce electricity or long-distance energy. These plants emit very little air pollution and have minimal impact on the environment. They are also very economical.

Originaldokument enthält an dieser Stelle eine Grafik!
Original document contains a graphic at this position!

Energy from flowing water is the oldest form of using power from nature. Low impact hydroelectric plants convert a renewable energy (water flows) into electricity and don´t emit any air pollution. Planning the dam carefully may cause new eco-systems for animals and plants. If dams also have fish ladders and if they fit into the nature, this is a very clean form of energy.

Originaldokument enthält an dieser Stelle eine Grafik!
Original document contains a graphic at this position!

Organic material, called biomass, can be burned in an incinerator to produce energy. Biomass recources include agricultural, forestry and food processing byproducts. In new facilities the biomass is converted into a combustible gas. Although biomass produces air pollution, it’s a more green and renewable power source than petrol-based fuels.



4 Pros and cons


Originaldokument enthält an dieser Stelle eine Grafik!
Original document contains a graphic at this position!




Originaldokument enthält an dieser Stelle eine Grafik!
Original document contains a graphic at this position!


+ Using alternative energy and renewable sources helps to reduce harmful emissions to our environment. Then our seriously impacted nature could recover. This will increase quality of life for this and all further generations.



- At this time alternative energy is more expensive than con-ventional energy. If conventio-nal power stations will be closed, lots of people will loose their jobs. But if new techniques are invented, and they sell good, prices will be reduced. And one should never forget thinking of our and our childrens environment, even if alternative power is more expensive.



5 Words

accumulate

ansammeln
agricultural

landwirtschaftlich
amount

Betrag, Menge
average

Durchschnitt
beneath

Unterhalb
combustible

leicht entzündlich
commercial power

althergebrachte Energieformen
dam

Kraftwerksdamm
decayed remains

verrottete Rückstände
demand

Anforderung
facilities

Anlagenkomplex
forestry

forstwirtschaftlich
alternative energy

Alternativenergie
green house effect

Treibhauseffekt
high impact hydro plant

Speicherkraftwerk mit hohem Damm
house-hold appliances

Haushaltsgeräte
incinerator

Müllverbrennungsofen
long- distance energy

Fernwärme
low impact hydro plant

Laufkraftwerk mit niedrigem Damm
nucleus

Kern eines Atoms
remote areas

abgelegene Orte
renewable

erneuerbar
semiconducors

Halbleiter
status quo

der jetzige Zustand
storage site

Lagerplatz
to devastate

vernichten
to emit

aussenden, abgeben


6 Sources


www.repp.org

www.dir.yahoo.com/Science/Energy/Biomass

www.dir.yahoo.com/Science/Energy/Free_Energy

www.dir.yahoo.com/Science/Energy/Geothermal

www.dir.yahoo.com/Science/Energy/Solar_Power

www.dir.yahoo.com/Science/Energy/Renewable

www.fortunecity.de/over.htm

www.howstuffworks.com




Wind energy











Originaldokument enthält an dieser Stelle eine Grafik!
Original document contains a graphic at this position!



A


M

E D F I G H K L

B
C



A


J

A
Rotor blades

H
Electronic transformer
B
Hub

I
Hydraulics system
C
Low speed shaft

J
Pillar
D
High speed shaft

K
Anemometer
E
Gearbox

L
Wind vane
F
Mechanical brake

M
Housing
G
Electrical generator




Solar thermal power











Originaldokument enthält an dieser Stelle eine Grafik!
Original document contains a graphic at this position!


A - Pool water inlet
I - Gate valve
B - Pump
J - Fossil fuel heater (if existing)
C - Filter
K - Chlorinator (if existing)
D - Check valve
L - Warm water returns to pool
E - Gate valve 1
M - Sensor
F - Drain valve
N - Automatic control box
G - Solar collectors
O - Electric or constriction valve (collector bypass)
H - Vacuum breaker and auto air relief
P - Booster pump



Photovoltaic system












Originaldokument enthält an dieser Stelle eine Grafik!
Original document contains a graphic at this position!










Geothermal energy



Originaldokument enthält an dieser Stelle eine Grafik!
Original document contains a graphic at this position!



Originaldokument enthält an dieser Stelle eine Grafik!
Original document contains a graphic at this position!



Hydro-power












Originaldokument enthält an dieser Stelle eine Grafik!
Original document contains a graphic at this position!









Biomass incinerator



Originaldokument enthält an dieser Stelle eine Grafik!
Original document contains a graphic at this position!














Originaldokument enthält an dieser Stelle eine Grafik!
Original document contains a graphic at this position!


Ende des Auszuges


Hier hast Du die Möglichkeit dieses Referat zubewerten
und somit die Gesamtbewertung mitzubestimmen!