Chapter 13: Energy - PowerPoint PPT Presentation

Loading...

PPT – Chapter 13: Energy PowerPoint presentation | free to download - id: 6703bb-ZTRlN



Loading


The Adobe Flash plugin is needed to view this content

Get the plugin now

View by Category
About This Presentation
Title:

Chapter 13: Energy

Description:

Using Solar Energy to Heat Water and Houses Passive solar heating system Heat is ... Houses Cooling Buildings Naturally Solar Thermal Systems PowerPoint ... – PowerPoint PPT presentation

Number of Views:21
Avg rating:3.0/5.0
Date added: 14 January 2020
Slides: 43
Provided by: Samand5
Category:

less

Write a Comment
User Comments (0)
Transcript and Presenter's Notes

Title: Chapter 13: Energy


1
Chapter 13 Energy
2
Renewable Energy
  • Types
  • Solar energy directly from the sun or indirectly
    from
  • Wind
  • Moving water
  • Biomass
  • Geothermal Energy
  • Renewable energy provides, only 8 of the worlds
    energy
  • If subsidies and tax breaks were removed from
    non-renewable energy today, then by, 2050, 50 of
    the earths energy could come form renewable
    sources.

3
Using Solar Energy to Heat Water and Houses
  • Active solar heating system
  • Uses heat absorbing liquids pumped to solar
    collectors outside, then pumped back though the
    house.
  • Passive solar heating system
  • Heat is allowed in through large superwindows
    facing the direction of the sun, then stored in
    the structures masonry.

4
Cooling Buildings Naturally
  • Living roofs
  • Lightly colored roofs that can reflect up to 80
    of light
  • High-efficiency windows

5
Solar Thermal Systems
  • These systems concentrate and transform energy
    from the sun into high temperature thermal
    energy
  • Examples
  • Central Receiver System computer controlled
    heliostats concentrate sunlight on a heat
    collecting tower to produce steam to drive a
    turbine.
  • Solar cooker used to concentrate heat to cook
    food and purify water.

6
(No Transcript)
7
Solar Cells
-Photovoltaic (PV) cells made of thin slates of
silicon with traces of metals, emit electrons
when sunlight passes through them.
  • Advantages
  • Safe/quiet
  • Little maintenance
  • No pollution when operating
  • Works on cloudy days
  • Disadvantages
  • Currently expensive
  • Contains toxic material.
  • Fossil fuels used in production
  • High land use

8
Hydropower
  • Uses kinetic energy of flowing and falling water
    to produce electricity.
  • Most common method is the use of large dams to
    create reservoirs, whose water is then slowly
    released though the dam turning a turbine and
    creating energy.

9
Wind
  • Turbines located on land or at sea convert wind
    into electricity
  • It has been estimated that only 1/5 of the wind
    energy from the worlds best sites could create 7
    times more electricity than the world currently
    consumes.

10
Wind
  • Advantages
  • Mostly pollution free
  • Low cost compared to other energy producers.
  • Little land use
  • Disadvantages
  • Needs steady winds
  • Noise pollution
  • Unsightly
  • Disrupts bird migration if not placed correctly
  • Some pollution in construction

11
Biomass
  • Plant material and animal waste that can be
    burned directly as solid biofuel or converted
    into liquid Biofuels
  • 95 of energy use in the poorest countries
  • Destroys biodiversity when forests are destroyed
    for biofuels and biomass plantations can deplete
    nutrient- rich soil with overuse.
  • The burning of biofuels releases CO2 and
    destroying forests reduces vegetation that could
    capture CO2.

12
Liquid Biofuels Created From Plants
  • Unlike gasoline and diesel fuel, Biofuels are not
    concentrated in a few countries, eliminating
    reliance on foreign fuel sources.
  • Biofuels can be used in pre-existing vehicles
    with only small alterations.
  • Examples Biodiesel, Ethanol

13
Biodiesel
Biodiesel is produced from the oil and fats of
vegetables.
  • Advantages
  • Reduced CO2 emissions
  • Better gas mileage
  • High net energy yield for oil palm crops
  • Disadvantages
  • Increase NOx emissions and smog
  • Higher cost than diesel
  • Low net energy yield for soybean crops
  • Loss of biodiversity

14
Ethanol
Created by converting starch in plants into
sugars which are then processed into Ethanol
  • Disadvantages
  • Low net energy yield (corn)
  • Higher CO2 emissions (corn)
  • Higher cost
  • May increase food prices
  • Advantages
  • High octane
  • Reduce in CO2 (sugarcane)
  • High net energy yield (sugarcane)
  • Can be mixed with gasoline or ethanol

15
Geothermal Energy
Heat stored in soil, underground rocks and
liquids in the earths mantle
  • Geothermal Heat Pump
  • During the winter a closed loop of buried pipes
    filled with fluids circulates heat from the
    ground into a building. The system does the
    opposite during the summer storing heat below
    ground.
  • Tapping into Hydrothermal Reservoir
  • Hot water underground is pumped to the surface
    where it is used to heat houses or to spin
    turbines

16
Geothermal Energy
  • Advantages
  • Very high efficiency
  • Lower CO2 emissions than fossil fuels
  • Low cost at favorable sights
  • Low land use and disturbances
  • Disadvantages
  • Scarcity of suitable sights
  • Can be depleted if used too rapidly
  • CO2 emissions
  • Noise and ordor

17
Hydrogen
  • Currently hydrogen fuel cells combine oxygen with
    hydrogen to produce electricity and water vapor.
  • Produces more energy per gram than does any other
    fuel and does not produce CO2
  • Hydrogen effects on the environment depends on
    the chemical system used to split it from water.
  • Current fuel cells are too expensive for
    commercial use

18
How Can We Make a Transition to a More
Sustainable Energy Future?
  • Step 1 Switch from large centralized macropower
    systems to smaller decentralized micropower
    system.
  • Step 2 The temporary use of natural gas to
    transition to locally available energy resources.
  • Step 3 Continue to use fossil fuels in large
    quantities but do so more efficiently.

19
How the Government Can Help
  • Step 1 Keep prices on renewable resources
    artificially low.
  • Step 2 Keep prices of non-renewable resources
    artificially high.
  • Step 3 Emphasize consumer education

20
Nuclear Energy
  • Task Boil water to produce steam that spins a
    turbine and generate electricity.
  • Uses nuclear fission reaction to provide heat
  • Takes place in reactor
  • Highly inefficient
  • Fuel for reactor is made from uranium ore mined
    from earths crust.

21
Nuclear Fuel Cycle
  • Three steps
  • Mining of uranium
  • Using uranium in reactor
  • Safely storing the resulting highly radioactive
    waste for thousands of years until radioactivity
    falls to safe levels.

22
Advantages of Nuclear Fuel Cycle
  • Large fuel supply
  • Low environmental impactwithout accidents.
  • Emits 1/6 as much CO2 as coal
  • Not a lot of land accidents or water pollution.
  • Low risk of accidents with safety systems.

23
Disadvantages of Nuclear Fuel Cycle
  • Cant compete economically without huge
    government subsidies.
  • Low net energy yield
  • Risk of catastrophic accidents
  • No acceptable solution for long-term storage of
    radioactive waste
  • Subject to terrorist attacks/spreads knowledge
    for building nuclear weapons.

24
Dealing with Radioactive Waste
  • 10 years after being removed from a reactor, a
    spent-fuel assembly would still emit enough
    radiation to kill a person standing 1 meter away
    in less than 3 mins.
  • Consensus that burial is the safest and cheapest
    method.
  • Shoot wastes into space or the sun?
  • Bottom Line No agreement whatsoever

25
Nuclear Fusion
  • Two isotopes of light elements are forced
    together at high temperatures until fused
    together releasing energy in the process.
  • Advantages
  • No risk of meltdown, or large release of
    radioactive materials from terrorist attack, and
    supplies electricity.
  • Still in laboratory stage.

26
Energy Efficiency
  • Important energy resource
  • US could save as much as 43 of all energy it
    uses by improving the energy efficiency of
    industrial operations, motor vehicles, and
    buildings.
  • Roughly 84 of all commercial energy is US is
    wasted.

27
Solutions to Reducing Energy Waste
  • Prolongs fossil fuel supplies
  • Reduces oil importsimproves energy security
  • Very high net energy yield
  • Low cost
  • Reduces pollution
  • Creates local jobs

28
We can Save Energy and Money in Industry
  • Cogeneration two useful forms of energy (such as
    steam and electricity) are produced from the same
    fuel source.
  • Replacing energy-wasting electric motors would
    help (it consumes ¼ of the electricity produced
    in the US)
  • Switch from low-efficiency incandescent lighting
    to high-efficiency fluorescent lighting.

29
We can Save Energy and Money in Transportation
  • Accounts for 2/3 of US oil consumption
  • Low fuel efficiency standards
  • Government can give consumers tax breaks or other
    economic incentives for more fuel-efficient
    vehicles.

30
We Can Design Buildings that Save Energy and Money
  • Better architecture and energy savings in
    buildings could save 30-40 of the energy used
    globally.
  • Green building certification standards in 21
    countries.

31
We can Save Energy and Money in Existing Buildings
  • Insulate the building and plug leaks
  • Use energy efficient windows
  • Heat houses more efficiently
  • Heat water more efficiently
  • User energy-efficient appliances
  • Use energy-efficient lighting.

32
Sources of Energy
  • Fossil fuels supply most of our commercial energy
  • Almost all of the energy that heats the earth and
    our buildings comes from the sun at no cost to
    us.
  • The three indirect solar energy is wind,
    hydropower and biomass

33
Commercial Energy
  • Comes from extraction and burning nonrenewable
    resources obtained from the earths crust
  • 92 of the worlds energy comes from these sources
  • 86 from carbon containing fossil fuels
  • 6 from nuclear power
  • The remaining 8 comes from renewable resources

34
(No Transcript)
35
Fossil Fuels
  • We depend heavily on oil
  • Petroleum or crude oil is a black, gooey liquid
    that consists for different combustible
    hydrocarbons
  • The petroleum is then sent to a refinery to be
    separated into different components with
    different boiling points and this is called
    refining

36
How Long Will Crude Oil Last?
  • The amount of barrels crude oil used each day
    would stretch from end to end circling the
    equator twice
  • Crude oil reserves will be 80 depleted between
    2050 and 2100

37
Three Options
  • 1. Look for more oil
  • 2. Use and waste less oil
  • 3. Find other energy sources

38
OPEC
  • Organization of Petroleum Exporting Countries
  • They control most of the worlds crude oil supply
    at about 78 of it
  • Members Algeria, Angola, Ecuador, Iran, Iraq,
    Kuwait, Libya, Nigeria, Qatar, Saudi Arabia, the
    United Arab Emirates, and Venezuela.
  • Saudi Arabia has most of it at 20
  • Canada is second with 16

39
United States
  • We use much more oil than we produce
  • We produce about 9 of the world Crude oil and
    use about 25 of it
  • We also only have 2 of the worlds oil reserves
  • This results in a massive annual transfer of
    wealth from the United States to oil-producing
    countries

40
Tar Sand and Oil Shale
  • Tar sand is a mixture of clay, sand, water, and a
    combustible organic material with a high sulfur
    content.
  • Oil shale are products from oily rocks
  • Both of these are potential supply's of heavy oil

41
Clean Oil Campaign
  • The U.S. coal industry is rich and politically
    powerful.
  • For decades it has fought to preserve its profits
    by opposing measures such as stricter air
    pollution standards for coal burning
  • In reality there is no such thing as clean coal

42
Convert Coal into Gaseous and Liquid Fuels
  • Solid coal can be converted into synthetic
    natural gas process called coal gasification
About PowerShow.com