Transcript Document

Chapter 10 Energy
Wind turbines in
Eastern Washington
Big Question
Can We Ensure a Reliable Supply of
Energy?
Types of Fuels
• Conventional or Alternative
• Conventional - fossil fuels including oil, gas
and coal
• Alternative – include wind, solar, water, wood,
nuclear, and geothermal.
• Conventional fuels are non-renewable, some
alternative fuels are renewable
Petroleum Products: Oil
• Oil is very abundant, but known supplies are
dwindling
• The oil resource is the entire amount on Earth
(total resource).
• An oil reserve is the portion of the resource
that we can extract now at a profit (proven
reserve)
When will we reach peak
production?
• World crude oil production is expected to peak
between 2020 and 2050 and cease by 2100
• Estimated total reserve is 3 trillion barrels of
oil
• Two other sources of oil are oil shale and tar
sands.
Petroleum Products: Natural Gas
• The worldwide known recoverable natural gas
will last approximately 70 years at the present
rate of use
• However it has only recently been widely
exploited, and more reserves are expected to
be discovered
Coal
Centralia, WA coal-fired power
plant produces about 10% of
Washington State's energy
How Coal is Made
• Formed as dead vegetation
was buried in sediments
• Then crushed, heated and
transformed over millions
of years into carbon rich
sedimentary rocks
• Other chemical elements
and soil particles mixed
with the dead plants and
form impurities
The Environmental Effects
Associated with Coal
• Coal may be extracted from underground mines
or from strip mining such as at Black Mesa
• Strip mining involves digging the coal out from
the surface.
• Produces soil
erosion,
increased
flooding risk
and acid
runoff
Environmental Effects Associated with
Petroleum Products
• Air pollution from combustion
• Leaks and spills during storage, transportation
and refining
• In 1989 the supertanker Exxon Valdez ran
aground in Prince William Sound Alaska, and
spilt 250,000 barrels (11 million gallons)
Alternatives Energy Sources: Solar
• Solar energy is renewable and therefore
sustainable.
• Solar energy is stored in wind, water, tides,
ocean currents, and organic matter (biomass)
Passive solar energy
Historically, houses were designed and oriented
to collect and use sunlight for heating
Active solar Energy
• Solar collectors
store the sun’s
energy to provide
space heating and
hot water
• Photovoltaics (PVCs)
convert sunlight
directly into electricity
• Thin layers of
semiconductors produce
an electric current when
sunlight falls on them
• Energy conversion
efficiency has increased
from 1–2% up to 18%
Wind Power
Water Power
Grand Coulee Dam in Washington
State. Note the outlet in the right hand
corner for irrigation water. The dam
serves to generate electricity (87% of
Washington's) and provide irrigation
water. Wikipedia photo.
Tidal Power
The primary areas
with potential for tieal
power are highlighted
in yellow. Most
studies show
Admiralty Inlet as the
highest potential for
tidal power due to the
strong currents there.
Biomass Energy
Biomass energy is a "closed" cycle, except for the use of any fossil fuel to utilize it.
Pellet stove heating home.
Pellet fuel is wood-based, so
it is renewable "recent"
carbon and doesn't
contribute to global CO2
except for the electricity
used to produce and run the
stove and transport the fuel
Fiat flex car. Note sugarcane
in background, the primary
source of fueld for cars in
Brazil
Geothermal Energy
Nuclear Energy
Nonbreeder Reactors: Fission Reactors
• 1 kilogram (2.2 pounds) of uranium oxide produces
as much heat as about 16 metric tons of coal.
• The heat from nuclear fission makes steam to run
turbines that generate electricity.
Environmental Problems of
Nuclear Power: Three Mile Island
• A cooling failure led to a meltdown on March
28, 1979
• A main water pump failed, increasing pressure
• A pressure release valve reduced pressure, but
then failed to close, and cooling water poured
out
• Reactor core overheated, leading to a partial
core meltdown
• Intense radiation was released inside the plant,
and some escaped into the atmosphere
Chernobyl
• Cooling system failed,
causing the temperature of
the reactor core to rise to
over 3000°C (5400°F),
melting the uranium fuel.
• Explosions removed the
top of the reactor building
• Graphite surrounding the
fuel rods caught fire.
Radioactivity
Energy: Storing it
The Grand Coulee Dam is the world's
5th largest, and includes a pumpstorage facility, including the ability to
flood Grand Coulee. Note the canal in
the upper right hand corner. Water is
pumped up into the canal, and can
also be pumped back into the reservoir
when there is excess electricity.
Energy: Transporting it
Conserving Energy
The UW's Center for Urban Horticulture, replaced after being
burned by ecoterrorists, was the UW's first certified "green"
building on campus.
• Design residential and office buildings to use
sun and wind
Steps to Energy Conservation
UW students conserving energy by walking and riding bikes
Source UW homepage, Traillink.com