Transcript UNIT 8
UNIT 8
Vocabulary
• Alternative energy sources, i.e.
renewable energies
Grammar and functions
• Hypothesizing: Conditional clauses
• Expressing opinion
• Integrated practice
EXPRESSING OPINION p 102
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In my opinion…
Personally, I think that…
I'd suggest that…
I (strongly)believe that…
I'm convinced that...
As far as I'm concerned…
I'd like to point out that…
What I mean is…
I'm pretty sure that
I agree with the fact that /
with you in …
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However… / On the contrary…
Yes, but don't you think…
I'm afraid I have to disagree.
Don't you think it would be
better...
I don't agree with …..
That's not entirely true because
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I don't think that...
The problem with that point of
view is that...
• NEITHER DO I
ORAL INTRODUCTION
1. What do you understand by renewable and
non-renewable energies?
2. Which renewable energies do you know?
Explain them
3. What does the use of non-renewable
energies imply?
4. Which are the advantages of renewable
energies? And those of non-renewable?
5. Would you like to live near a coal power
plant? And near a wind farm? Why (not)?
VIDEO: 5 GREEN ENERGIES
http://www.ehow.com/video_4952000_five-forms-greenenergy.html?cp=1&pid=1&wa%5Fvrid=1f0b9827%2Ded80%2D4723%2Dac8d%2D265bc84b95b6&wa%5Fvlsrc=continuous
1. Have all of them the same age? They have not all been around for the
same length of time.
2. What is the age of Geothermal energy? It has been there since the
earth began
3. Where is it? under ground, it's in the hot rocks below ground.
4. What can be the depth of these rocks? as much as a kilometer down.
5. How can we fracture these rocks? by exploding dynamite
6. What can we do then? pump water down and pump the water back up,
and when it comes back up it's hot.
7. Which kind of energy is the most important one today? biomass,
8. What is it? plants.
9. Where do plants get their energy from? the sun using the chlorophyll,
the green substance in the leaves.
10. What does biomass do? It absorbs energy from the sun,
11. How can we reuse that energy? by turning it into biodiesel
12. It can be used to replace what? the fuel produced from oil and therefore
conserve oil.
5 GREEN ENERGIES
13. Where does Hydro energy come from? It is energy from the sun.
14. What happens to the water in rivers? the water evaporates due to the
sun’s energy, it then precipitates into rain and falls into the rivers,
15. How can we produce electricity? we build dams, put it in turbines and
we end up with electric power.
16. Where is there always wind?. near the coast due to the changing
temperature of the sea and the land
17. What can those winds be used for? drive wind turbines.
18. What are the components? large propellers on a tall tower and at the
top of the tower are turbines, and turbines produce electricity.
19. What is solar energy based on? silicon technology.
20. How does it work? When we shine light onto a piece of silicon chip it
produces a small electric current, if you put enough of them together
you get a lot of energy.
21. What is the problem? This is quite an expensive form of reusable energy .
22. What is its main use? in devices which have to be carried around, like
on your calculator you only need a small amount of energy.
ENERGY CRISIS
Paragraph I
1.Which do you think those present trends are?
2.Why will there be a “major crisis”?
3.What will be the consequences of present
trends?
4.Since means ..........
5.Find two words in this paragraph that are
synonyms.
6.Find a Conditional Clause
ENERGY CRISIS
• At present (6), almost all our energy comes FROM fossil fuels
(7), i.e. (THAT IS)(8), oil, COAL and natural gas.
• The Earth's reserves of fossil fuels have BEEN formed
BY/FROM organic matter subjected TO enormous heat and
pressure FOR millions of years (9).
• But such reserves are finite (10). Because power demand is
increasing very rapidly (11), fossil fuels will BE exhausted(12)
within a relatively short time.
• We can estimate the amount of recoverable fuel under the
surface of the Earth (13), and we know the rate at WHICH it is
BEING extracted (14).
• Fairly (15) simple calculations can therefore determine ITS
remaining life (16).
• If present trends continue, gas and oil reserves will BE
exhausted by the middle of the 21st CENTURY.
• Similar estimates (17) about coal reserves suggest a projected
supply (18) of 200-250 years. Of course, long before
THESE/FOSSIL fuels are exhausted, demand will greatly
exceed supply (19)
NOUNS/ADJ from VB
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NOUNS
PRODUCE- Production-producer
PRESS- Pressure
ESTIMATE- estimate
SUPPLY- Supply
CONSUME- Consumer-consumption
ADJECTIVES
RECOVER – Recoverable
PROJECT – Projected
SUFFICE- Sufficient
REMAIN- Remaining
CONDITIONAL CLAUSES
IF-CLAUSE
MAIN CLAUSE
TYPE 0/I (laws / possibility )
Present
Present (laws) = Type 0
Future (possibility)
Modal (may, can, should…)
TYPE II (probability)
Simple Past
(VB-ED) WERE
Conditional
(WOULD/COULD/MIGHT +INF)
TYPE III (impossibility)
Past Perfect
(HAD+PP)
Perfect Conditional
(WOULD HAVE + PP)
CONDITIONAL EXPRESSIONS
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UNLESS + PRESENT = IF + Vb in negative
PROVIDED (THAT) = IF and only IF
IN CASE (THAT) = In the event (that)
AS LONG AS = on the condition (that)
AS FAR AS = on the condition (that)
OTHERWISE= IF NOT
WHEN can also have a conditional meaning
(used in conditional TYPE I)
EXER: CONDITIONAL
1. If we HAD NOT WASTED the fossil fuels, they WOULD HAVE LASTED longer
2. We COULD DEVELOP other alternative sources if we SPENT more money on
research
3. If a cold object IS PUT in contact…, the latter DECREASES
4. Unless actions ARE TAKEN now…, CO2 emissions ….
5. If nuclear power WERE NOT so dangerous, everybody WOULD AGREE to
install nuclear power plants.
6. If we HAD DEVELOPED other alternative sources, fossil fuels WOULD NOT
HAVE RUN OUT so rapidly (III).
7. If a reactor only LASTS 25 years, in a few years we WILL HAVE hundreds of
them stored all over the world. (I)
8. Electricity WOULDN’T HAVE BECOME a major source … if the relationship
between electricity & magnetism HADN’T BEEN DISCOVERED
9. If we DID NOT EMPLOY fossil fuels in the production of electricity, these
materials COULD BE USED to manufacture other valuable things (II)
10. Lots of radioactivity WOULD REMAIN … if there WERE a nuclear accident (II)
11.If two magnets ARE BROUGHT together, like charges (WILL) REPEL each
other. (I)
12. The ice caps WOULD MELT DOWN if the temperature of the Earth ROSE 0.5C
CONDITIONAL: JOIN
1. UNLESS we have safe containers, we cannot dispose
of the toxic waste.
2. IF/ WHEN you release the button, the recording time
will be set.
3. IF more people used public transport, it would be
possible to park your car in the city center.
4. If you had studied harder you would have passed
your exam.
5. IF the temperature rises/rose above 1,000ºC, the boiler
will/would explode.
ALTERNATIVE ENERGY- List Conditionals
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What can we do? DEVELOP ALTERNATIVE SOURCES OF
POWER
And we will never succeed UNLESS WE TRY
INSTEAD OF BURNING FOSSIL FUELS we should be
concentrating on what? MORE ECONOMIC USES OF
ELECTRICITY
Why? BECAUSE ELECTRICITY CAN BE PRODUCED FROM
ANY SOURCE OF ENERGY
How would our resources last longer? IF WE DIDN’T WASTE SO
MUCH ENERGY
How can you save more energy? BY CONSERVATION THAN
YOU CAN PRODUCE for the same money
UNLESS WE DO RESEARCH ON SOLAR ENERGY, WIND
POWER, WAVE POWER, TIDAL POWER, HYDROELECTRIC
schemes, our FOSSIL FUELS WILL RUN OUT
What are other countries doing? SPENDING MUCH MORE
THAN US ON RESEARCH
Don’t forget that ENERGY FROM THE SUN, THE WAVES, THE
WIND LASTS FOREVER
We won’ survive UNLESS WE START WORKING ON
CLEANER, SAFER SOURCES OF ENERGY
TRANSLATION
• …on coal, oil and natural gas to obtain their energy.
• Fossil fuels are non renewable, i.e.,
• By contrast/contrarily to this/on the contrary/unlikely,
renewable energy sources -such as/like wind or solar
energy-.
• Most renewable energy comes …. from the sun.
• … can be directly used for heating and lighting homes …,
for generating electricity, and …., solar cooling and…..
• …whose energy can be captured by means of/with wind
turbines.
• ….cause water to evaporate.
• …. turns into/is converted into/becomes rain and ….
• ……its energy can be captured using hydroelectric power.
TRANSLATION
• Sunlight also causes/(makes) plants to/(ø) grow.
• The organic matter that forms/composes/makes up those plants
is known as biomass.
• …. fuels for transportation and chemical products.
• Hydrogen can also be found in many …, as well as in water.
• It is the most abundant element on the Earth.
• But it does not occur naturally as a gas.
• … with other elements, such as/like oxygen, to make water.
• …, hydrogen can be burnt as a fuel or converted into electricity.
• Not all renewable energy resources come from the sun.
• …, and the heating and cooling of buildings.
• In fact, ocean energy comes from a number of sources.
• In addition to/besides tidal energy, … , which are driven by the
tides and the winds.
• …. more than the ocean depths/bottom, creating a difference in
temperature that can be used as an energy source.
LISTENING
1. power derived from the sun
2. they will eventually be exhausted
3. a huge parabolic mirror (that focuses the
sun’s heat onto a small area).
4. more than 7,232ºF (4,000ºC)
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- to raise steam and generate electricity..
- or for scientific research
6. 1,300 moving mirrors (covering an area of 5
acres – 2 hectares)
7. 2½ million kilowatt-hours of electricity
(annually)
LISTENING
• Solar energy is used increasingly FOR DOMESTIC HEATING.
• Heat is collected BY EXPOSING A LARGE DARKENED
METAL PLATE,
• covered with one or more LAYERS OF GLASS, to the sun.
• WATER OR AIR IS PASSED THROUGH TUBES attached to
the plate
• and either circulated through the building OR STORED.
• Hot water is stored in INSULATED TANKS.
• Hot air…, which hold the heat UNTIL IT IS REQUIRED to warm
up air for circulation around the house.
• Sunlight CAN ALSO BE CONVERTED DIRECTLY INTO
ELECTRICITY in a solar CELL,
• and there is research…. to produce CHEMICAL ENERGY by
the same sort of reaction AS PHOTOSYNTHESIS IN PLANTS
GRAMMAR REVISION: Solar E
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Today over 90% of our energy comes FROM fossil FUELS, i.e., COAL, OIL and
natural gas.
THEY are also important raw materials FOR our CHEMICAL INDUSTRIES
People think we should limit their use AS fuels, otherwise the world´s supplies will
soon run OUT
Much research is BEING done on the practical use of the sun FOR heating buildings.
Solar energy is transmitted from the sun, THROUGH space, to the earth AS
electromagnetic radiation.
It must BE converted INTO heat before IT can be used.
Various types of solar energy collectors or absorbers are used to convert the sun´s
radiation INTO heat.
In a building where a solar system has BEEN installed IT provides water as well AS
space heating.
This solar system, based ON water-heating, works LIKE this.
Each of the collectors, placed ON the roof, consists OF a fibreglass tray WHICH
holds a number of copper tubes under a special glass cover.
The tubes are fixed TO a blackened surface WHICH absorbs energy from the sun.
The sun´s rays passing THROUGH the glass, heat the water IN the tubes.
SOLAR ENERGY: reorder
• 4- The purpose of any solar system is to collect solar
radiation and convert it into useful thermal energy
• 6- It consists of a number of absorbers or collectors
• 3- These are made of plates of fiber with copper
tubes inside
• 9- The tubes are connected to a metal surface
• 2- This surface is black in order to absorb more
energy
• 10- The system works as follows: the sun rays pass
through the glass
• 8- They heat water flowing through the copper tubes
• 5- When the water is heated it produces steam
• 1- and the steam is used to move a turbine, which
turns a generator
• 7- This device then transforms heat into electricity
20% RENEWABLE ENERGY (0:30)
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What kind of energy did our grandparents’ watermills and windmills
produce? MECHANICAL ENERGY FROM RENEWABLE SOURCES
And the modern versions? ELECTRICITY
What do Windmills do? TRANSFORM WIND INTO ELECTRICITY
What does Hydraulic energy produce? ELECTRICITY
The process is the same in SMALL HYDRAULIC PLANTS and BIG
DAMS
The ENERGY POTENTIAL of a head of water is converted ELECTRIC
ENERGY
What does Geothermal energy use? HEAT FROM THE DEPTHS OF
THE EARTH
What for? TO PRODUCE HEAT AND ELECTRICITY
Solar energy can produce HEAT AND ELECTRICITY
Solar heat panels installed ON A ROOF can cover most HOT WATER
NEEDS for sanitary purposes and can serve as backup for DOMESTIC
HEATING
What area of solar panels were installed in Europe in 2006? 20
MILLION M2
What do solar mirror plants convert? SOLAR ENERGY INTO
ELECTRICITY
How? USING PANELS OF PHOTOVOLTAIC CELLS
20% RENEWABLE ENERGY (biomass)
18. What is biomass? PRODUCED FROM VEGETAL,
ANIMAL OR URBAN WASTE
19. Which is the most widespread application of biomass?
COMBUSTION OF WOOD FOR DOMESTIC HEATING
20. And in industry or towns? GENERATE HEAT OR
ELECTRICITY
21. How is biogas produced? BY FERMENTATION OF
WASTE (e.g. liquid manure used in farms or OTHER
ORGANIC WASTE
22. It is used to produce what? HEAT OR ELECTRICITY
23. And purified biogas? CAN BE USED AS GASEOUS
BIOFUEL
24. What else does biomass make possible? LIQUID
BIOFUELS, BIODIESEL & BIOETHANOL
HOW SOLAR PANELS WORK
1. SUNLIGHT is made up of TINY packets of ENERGY called photons
2. Every minute enough of this energy reaches the earth TO MEET THE
WORLD’S ENERGY DEMAND FOR A WHOLE YEAR
3. Photovoltaic panels CONSIST OF MANY SOLAR CELLS
4. What is the material used? SILICON
5. What is the characteristic of this element? IT IS ONE OF THE MOST
COMMON ELEMENTS ON EARTH
6. The individual cell IS DESIGNED WITH A POSITIVE and A NEGATIVE
LAYER to create AN ELECTRIC FIELD, just LIKE IN A BATTERY
7. As photons ARE ABSORBED IN THE CELL the energy CAUSES
ELECTRONS TO BECOME FREE
8. The electrons move towards THE BOTTOM OF THE CELL and exit
THROUGH THE CONNECTING WIRE
9. This FLOW OF ELECTRONS is WHAT WE CALL ELECTRICITY
10. BY COMBINING SOLAR CELLS and PHOTOVOLTAIC PANELS we
produce just the right AMOUNT OF ELECTRICITY to perform a specific
job, no matter HOW LARGE OR SMALL
GRAMMAR REVISION
• Currently some 50% of the carbon dioxide (CO2) released IN
the UK is the result of THE energy consumed in buildings.
• If reductions in CO2 levels are to be achieved, IT is important
that the amount of CO2 released from THE energy used in
buildings IS/BE reduced significantly.
• Upgrading the energy performance of the existing building
stock is therefore AN extremely important objective and a
considerable effort should be made to achieve this.
• However, AS much new building is taking PLACE and many
of these buildings will have considerable lifetimes, it IS very
important that these new buildings be constructed with
minimal impact.
• Fortunately it is easier TO improve the energy performance of
new buildings and improvements can often also BE made for
a much lower cost if they are taken INTO account early
enough in the design process.
VIDEO: RENEWABLE BASICS
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ENERGY = THE CAPACITY TO DO WORK
ELECTRICITY, NATURAL GAS, WOOD, HEATING OIL, COAL
Each has STRENGTHS and WEAKNESSES
We forgot the sun in favour of FOSSIL FUELS
At a time the sun was as important AS FIRE
What does he say about fossil fuels? FINITE RESOURCE, NOT
RENEWABLE
Which is the definition of RENEWABLE? INEXHAUSTIBLE
the two sources : EARTH’S INTERIOR HEAT and THE SUN
Which are the advantages of the sun? AVAILABLE EVERYWHERE AND
IN QUANTITIES THAT ARE VERY USEFUL TO THE KIND OF WORK
WE WANT TO DO
And uses? HEATING & COOLING OUR HOMES, HEATING WATER,
GENERATING ELECTRICITY
When should we use the sun given the ubiquity of fossil fuels? WHEN F.F
or UTILITY GRID ELECTRICITY are NOT READILY AVAILABLE, i.e.
REMOTE LOCATIONS
VIDEO: RENEWABLE BASICS
DIAGRAM : 4:45-5:30
• What kind of illustration is it? A FLOW CHART
• What is it about? THE CURRENT US ENERGY STORY
• Explain the graph:
– Left= SOURCES OF E FOR THE ENTIRE US SUPPLY : COAL,
NATURAL GAS, CRUDE OIL, NUCLEAR GENERATED
ELECTRICITY, ALL RENEWABLE SOURCES, IMPORTED
PETROLEUM
– Right = USES: RESIDENTIAL, COMMERCIAL, INDUSTRIAL &
TRANSPORTATION
• Not isolate WHICH SOURCES are used for WHICH
PURPOSES AS there are many cases where a given
ENERGY SOURCE is used to do many kinds of useful work
• It shows the overall US ENERGY PRODUCTION and
CONSUMPTION