solar energy solar power can be used for making hot water and for producing electricity photovoltaic...
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Resources and sustainability
Solar Energy
• Solar power can be used for making hot water and for producing electricity
Photovoltaic panel (electricity) solar thermal panel (hot water)
Advantages Disadvantages
Solar energy is free - it needs no fuel and produces no waste or pollution.
Doesn't work at night.
In sunny countries, solar power can be used where there is no easy way to get electricity to a remote place.
Very expensive to build solar power stations
Handy for low-power uses such as solar powered garden lights and battery chargers, or for helping your home energy bills.
Can be unreliable unless you're in a very sunny climate.
Wind Energy
Producing wind energy is very old. It has been already used in the Middle Ages.
• The best places for wind farms are in coastal areas, at the tops of rounded hills, open plains and gaps in mountains - places where the wind is strong and reliable. Some are offshore.
• To be worthwhile, you need an average wind speed around 25 km/h.
There are different ways of using wind energy
Freighter shipDiesel engine plus sailSaves 30%
Motorway turbinesTailwind of the passing cars turns the wheel, creating energy
Advantage Disadvantages
Wind is free, wind farms need no fuel. The wind is not always predictable - some days have no wind.
Produces no waste or greenhouse gases. Suitable areas for wind farms are often near the coast, where land is expensive.
The land beneath can usually still be used for farming.
Some people feel that covering the landscape with these towers is unsightly.
A good method of supplying energy to remote areas.
Can be noisy. Wind generators have a reputation for making a constant, low, "swooshing" noise day and night, which can drive you nuts.
• A dam is built to trap water, usually in a valley where there is an existing lake.• Water is allowed to flow through tunnels in the dam, to turn turbines and thus drive generators.
Water power
Advantages Disadvantages
Once the dam is built, the energy is virtually free.
Building a large dam will flood a very large area upstream, causing problems for animals that used to live there.
No waste or pollution produced. Finding a suitable site can be difficult.
Much more reliable than wind, solar or wave power.
The dams are very expensive to build.
Electricity can be generated constantly.
Water quality and quantity downstream can be affected, which can have an impact on plant life.
Geothermal power • Heat energy from underground• Hot rocks underground heat water to produce
steam• We drill holes down to the hot region, steam comes
up, is purified and used to drive turbines, which drive electric generators
Advantages Disadvantages
Geothermal energy does not produce any pollution, and does not contribute to the greenhouse effect
The big problem is that there are not many places where you can build a geothermal power station
The power stations do not take up much room
Sometimes a geothermal site may "run out of steam", perhaps for decades
Once you've built a geothermal power station, the energy is almost free
Hazardous gases and minerals may come up from underground, and can be difficult to safely dispose of
Future Energy
1. The moving air from the cars turns into wind energy for the turbine
2. The turbines generate electricity3. The electronic energy provides light for the cars on
the street
Highway lighting
Bridge of the future for alternative energy
Water• The most important resource we have to
watch out for• The less water we have, the more valuable it is• Polluting water is a big problem nowadays• Already one person in five has no access to
safe drinking water
• 1.1 billion people have no clean water• Contaminated water kills 5 million people in a
year• Only 2.5% of the world's water is not salty,
and two-thirds of that is locked up in the icecaps and glaciers
• Humans have less than 0.08% of all the Earth's water available for them
How can we save water
We should use water economically- Turn off the tap when you brush your teeth- Take a shower instead of a bath- Install a dual-flush toilet- Never leave a tap dripping
- Use household machines (washing machine, dishwasher) fully loaded
- Report burst pipes immediately to the local water company
- Collect rain water, for flushing the toilet or sprinkling flowers
- Use 'grey' water on the garden- Use cold water to wash out jars for recycling
Food production
• Sustainable food:– Sustainable food takes into account
environmental, health, social & economic concerns and consists of eight inter-related principles
1. Local & seasonal• The food has to travel too long ways• Thats not sustainable for our oil resources• Out-of-season food, needs too much energy to
get cooled2. Organic & sustainable farming• We have to minimize the carbon emission in the
agriculture• We should use biological fertilizer• potentially offsetting of greenhouse gas
emissions from agriculture through soil carbon sequestration alone
3. Reduce foods of animal origin & maximize welfare standards• Meat and dairy products are among the
most energy & greenhouse-gas intensive food products of all
4. Excludes fish species identified as at risk• Overfishing is the greatest single threat to
marine wildlife and habitats, with nearly 80% of world fish stocks fully or overexploited
• Many different species are already overfished
5. Fair-trade-certified products• It creates social & economic opportunities
for producers and workers who have been exploited
• Fair-trade ensures producers are paid fairly for their work
6. Food democracy• Decisions & profits are taken by a handful
of large companies driving down prices & maximizing profits at the expense of farmers
7. Reduction of waste and packaging• It is hard to recycle packaging waste• Buying local and seasonal food reduces the need
for unnecessary packaging• Food should come with the minimum of
packaging8. Promote health and well being• There are just 18 % of the adults, who eat the
recommended minimum of five portions of fruit & vegetables a day
• Childhood obesity & other food related illnesses are on the increase
• http://news.bbc.co.uk/hi/english/static/in_depth/world/2000/world_water_crisis/default.stm
• http://www.darvill.clara.net/altenerg/hydro.htm• http://indiequill.files.wordpress.com/2008/06/lightning1.jpg• http://www.spektrumdirekt.de/sixcms/media.php/912/thumbnails/1200_
Island%20Geysir_by_Stormfire_pixelio.de.jpg.608672.jpg• http://dev.3p-institute.org/wp-content/uploads/2008/08/fische.jpg• http://mirror-sg-wv0.gallery.hd.org/_exhibits/places-and-sights/_more200
2/_more01/Cuba-Trinidad-Caribbean-Sea-Playa-Ancon-clear-water-fish-1-MY.jpg
• http://www.wide-wallpaper.de/wallpapers/termeszet/vizesesek/_teljeskep/32238.jpg
• http://siteboat.com/wp-content/uploads/2008/10/green_energy.jpg• http://yeki1dooneh.files.wordpress.com/2009/08/blue_blue_sky_by_eev
ee90.jpg• http://kindling.org.uk/sustainable-food-definition • http://cea.mblast.com/ws/wfaward/rsp/votenomination.asp?SessionID=3
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BennettFanni
IsabelleJohannes
LauraWalter
Thank you for your attention!