EESA01 Lecture11-2011-compressed - EESA01
Lecture
11


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Unformatted text preview: EESA01
Lecture
11
 Energy,
Impacts,
and
Alterna8ves
 November
28,
2011
 Lecture
11
–
Energy,
Impacts,
and
Alterna8ves
 1
 Textbook
Reading
 •  For
this
week
AND
next
week,
you
will
have
to
have
 read
ALL
of
chapters
15,
16,
AND
17.

(They
are
each
 quite
short.)


 Lecture
11
–
Energy,
Impacts,
and
Alterna8ves
 2
 Sources
of
Energy
 3
 Global
Energy
Use
 Figure 15.3 Lecture
11
–
Energy,
Impacts,
and
Alterna8ves
 4
 Energy
Use
in
Canada
 Figure 15.1 Lecture
11
–
Energy,
Impacts,
and
Alterna8ves
 5
 Energy
for
Energy
 •  •  •  •  It
takes
energy
(drilling,
construc8on,
transport,
etc)
 to
get
and
deliver
the
energy
we
use.
 Net
Energy:
difference
between
energy
returned
and
 energy
invested
 Net
Energy
=
Energy
Returned
–
Energy
Invested 
 Energy
Returned
on
Investment
(EROI):
ra8o
of
 energy
returned
to
energy
invested
 EROI
=
Energy
Returned/Energy
Invested 
 Higher
values
for
each
indicate
more
efficient
energy
 capture
 Lecture
11
–
Energy,
Impacts,
and
Alterna8ves
 6
 EROI
Changes
Over
Time
 •  •  •  •  •  •  •  Historically,
we
have
always
taken
the
easiest
to
 obtain
resources
first
 This
means
that
oil,
gas,
and
coal
are
all
ge\ng
more
 and
more
difficult/expensive
to
obtain
 Oil
and
gas
in
1940s:
EROI
~
100:1
 Oil
and
gas
today:
EROI
~
15:1
 Canadian
tar
sands:
EROI
~
5:1
 Ethanol
fuel:
EROI
~
2:1
 Solar
panels:
EROI
~
1:1
 Lecture
11
–
Energy,
Impacts,
and
Alterna8ves
 7
 Coal
 Figure 15.5 •  •  Formed
from
peat
deposits
laid
down
300‐400
 million
years
ago
and
put
under
intense
pressure
 with
liale
diges8on
or
decomposer
ac8on
 It
is
a
ROCK
and
provides
~1/4
of
world’s
commercial
 8
 energy
consump8on
 Coal
Mining
 •  •  •  Subsurface
Mining:
shaes,
 networks
or
tunnels
to
 expose
coal
seams.

It
is
 very
hazardous.
 Strip
Mining:
heavy
 machinery
removes
strips
 to
expose
seems
from
 surface
down.
 Mountaintop
Removal
 Lecture
11
–
Energy,
Impacts,
and
Alterna8ves
 9
 “Clean
Coal”
 •  •  Depending
on
source
(freshwater
vs
marine),
coal
 contains
variable
amounts
of
sulphur
and
other
 pollutants,
such
as
mercury
and
arsenic
 “Clean
coal”
involves
reducing
toxic
chemical
release
 using
technology
either
before
or
aeer
coal
burn
 –  –  –  More
efficient
burn
(fluidized
bed)
 Gasifica8on
(use
coal
to
create
synthe8c
cleaner
fuel)
 Scrubbers
(calcium/sodium‐based
absorbent)
 Lecture
11
–
Energy,
Impacts,
and
Alterna8ves
 10
 Coal
Mining
Impacts
 1.  2.  3.  4.  5.  Habitat
loss
(specifically
strip
mining)
 Soil
erosion
 Air
pollu8on
in
burning
 Generates
other
hazardous
solid
wastes
 Acid
Drainage:
sulphur
minerals
in
exposed
rock
react
 with
air
and
water
to
make
sulphuric
acid,
which
can
 run
off
and
leach
out
metals
(increase
toxicity)
 6.  Rehabilita8on
and
restora8on
efforts
rarely
return
 things
to
“normal”
and
certainly
not
in
short
 8meframes
 7.  Dangerous

shae
collapse,
black
lung
disease
 Lecture
11
–
Energy,
Impacts,
and
Alterna8ves
 11
 Natural
Gas
 •  •  •  •  Principal
gas
in
natural
gas
is
methane,
CH4
 Provides
~1/4
world’s
commercial
energy
use
 Biogenic
gas:
produced
by
ac8on
of
bacteria
who
 decompose
organic
maaer
anaerobically
 Thermogenic
gas:
results
from
compression
of
 organic
maaer
and
hea8ng
deep
beneath
surface
 –  –  •  •  Can
be
formed
directly
as
a
resul8ng
of
hea8ng
and
 compression
of
oil
and
coal;
kerogen
is
a
precursor
to
both
 oil
and
natural
gas
 Most
of
this
is
found
in
conjunc8on
with
oil
and/or
coal
 Considerably
cleaner
than
burning
oil
or
coal
 World
supplies
will
be
depleted
in
next
50‐60
years
 Lecture
11
–
Energy,
Impacts,
and
Alterna8ves
 12
 Oil:
World’
Most
Used
Fuel
 •  •  •  •  •  •  37%
of
global
commercial
energy
consump8on
 First
oil
well:
Oil
Springs,
Ontario
(15
min
outside
my
 hometown)
 At
less
than
0.005%
of
world’s
popula8on,
Canada
 consumes
2.5%
of
world’s
oil
 Formed
from
organic
material
under
heat
and
 pressure
~1.5
to
3
km
beneath
ground
 Cons8tuents
vary
depending
on
how
the
oil
was
 formed
 Technically
recoverable
+
economically
recoverable
=
 proven
recoverable
reserve
 Lecture
11
–
Energy,
Impacts,
and
Alterna8ves
 13
 Drilling
for
Oil
 •  •  •  •  Oil
spewing
from
holes
is
a
 very
temporary
phenomenon
 and
ends
when
pressure
built
 up
in
the
deposit
is
relieved
 over
8me
 Primary
extracHon
usually
 captures
about
1/3
of
oil
 Secondary
extracHon
involves
 injec8ng
solvents
or
water
 into
the
ground
to
remove
 more
 Prevalence
of
secondary
 extrac8on
related
to
oil
$$
 Lecture
11
–
Energy,
Impacts,
and
Alterna8ves
 14
 Oil
Used
for
More
than
Gasoline
 Lecture
11
–
Energy,
Impacts,
and
Alterna8ves
 15
 “Peak
Oil”
 •  Refers
to
when
we
will
have
used
½
of
the
world’s
oil
 reserves
and
is
assumed
to
coincide
with
when
oil
 produc8on
will
begin
to
decline
 Figure 15.11 Lecture
11
–
Energy,
Impacts,
and
Alterna8ves
 16
 Canada’s
Oil
Sands
 •  •  •  •  •  •  AKA
“tar
sands”

 Bitumen
(heavy
petroleum)
that
is
stuck
in
near‐ surface
sand
and
clay
deposits
(~1
to
20%
bitumen)
 Too
thick
to
drill
for,
so
it
is
surface
mined
similarly
to
 surface
mining
coal
 Majority
of
world’s
oil
sands
deposits
are
in
 northeastern
Alberta
and
in
Venezuela
 Rela8vely
expensive
extrac8on
process,
but
buoyed
 by
high
oil
prices;
a
lot
of
mining
companies
trying
to
 break
in

 Alberta
oil
sands:
~175‐200
billion
barrels
(117
litres
 in
a
barrel)
 Lecture
11
–
Energy,
Impacts,
and
Alterna8ves
 17
 Canada’s
Oil
Sands
 Figure 15.13 Lecture
11
–
Energy,
Impacts,
and
Alterna8ves
 18
 Impacts
Summary
 •  Remember…2
levels
of
impacts:

 1.  Impacts
related
to
the
extrac8on
of
the
energy
resource
 2.  Impacts
related
to
the
use
of
the
extracted
resource
 •  •  Extrac8on
can
devastate
landscapes,
use
a
lot
of
 energy
itself
(CO2
emission),
usually
uses
enormous
 quan88es
of
water
(especially
oil
sands),
and
 contributes
to
air
and
water
quality
degrada8on
 Of
course,
fossil
fuel
emissions
(i.e.,
burning
it!)
 contributes
pollutants,
GHG’s
in
the
atmosphere,
and
 drives
global
climate
change
 Lecture
11
–
Energy,
Impacts,
andAlterna8ves
 19
 The
New
“Thing”:
Carbon
Capture
and
 Storage
(CCS)
 •  •  •  Short
descrip8on:
it
is
the
diversion
of
CO2
releases
 to
storage
“reservoirs”
before
they
get
into
the
 atmosphere
 2
likely
reservoirs:
deep
ocean
and
deep
 underground
geological
forma8ons
 Extremely
liale
is
know
about
consequences
 Figure 15.16 Lecture
11
–
Energy,
Impacts,
and
Alterna8ves
 20
 •  •  •  “Conven8onal”
Alterna8ves
to
Fossil
 Fuels
 Alterna8ves
exist
that
are
renewable
and
less
 environmentally
damaging
than
fossil
fuels
 Currently,
nearly
all
cost
considerably
more
 Principle
“conven8onal”
alterna8ves:

 1.  Hydroelectricity:
from
moving
water
(mostly
via
dams)
 2.  Nuclear
power:
from
nuclear
fission
 3.  Biomass
energy:
from
burning
biomass
(plants,
trees,
peat)
 •  Considered
“conven8onal”
because
they
already
play
 an
important
part
 Lecture
11
–
Energy,
Impacts,
and
Alterna8ves
 21
 Changing
Carbon
Emissions
 Lecture
11
–
Energy,
Impacts,
and
Alterna8ves
 22
 Hydroelectric
Power
 Lecture
11
–
Energy,
Impacts,
and
Alterna8ves
 23
 Hydroelectric
Power
Benefits
 1.  Renewable
resource
 2.  No
fossil
fuels
used
in
producing
power,
so
 no
CO2
emission
(cannot
be
said
for
 construc8on
of
dam)
and
liale
to
no
air
 pollutants
released
 3.  EROI
=
>
10:1
 Lecture
11
–
Energy,
Impacts,
and
Alterna8ves
 24
 Hydroelectric
Power
Impacts
 1.  Habitat
destruc8on
upstream
(flooded)
and
 downstream
(too
liale
water)
 2.  Alters
natural
river
hydrology
 3.  Fragments
habitat
for
fish;
other
wildlife
 4.  Traps
important
nutrients
that
would
otherwise
get
 to
downstream
areas
 5.  Thermal
polluHon:
shallow
downstream
water
 warms;
large
releases
of
water
can
lead
to
cold
 “shock”
 6.  Can
affect
geology

cause
earthquakes
 7.  Can
be
catastrophic
if
failure
of
dam
 8.  Most
major
rivers
already
dammed

liale
 opportunity
for
expansion
 Lecture
11
–
Energy,
Impacts,
and
Alterna8ves
 25
 Nuclear
Power
 Figure 16.6 Lecture
11
–
Energy,
Impacts,
and
Alterna8ves
 Figure 16.9 26
 Pros
and
Cons
versus
Coal
 Lecture
11
–
Energy,
Impacts,
and
Alterna8ves
 27
 Small
Chance
of
Accidents
and
Security
 are
Issues
 Lecture
11
–
Energy,
Impacts,
and
Alterna8ves
 28
 Recent
Issues
 Photo: bbc.co.uk Lecture
11
–
Energy,
Impacts,
and
Alterna8ves
 29
 Radioac8ve
Waste
Disposal
 •  •  •  •  •  •  Take
away
security
issues
and
thwar8ng
all
poten8al
 accidents,
we
s8ll
have
to
deal
with
spent
fuel
rods
 About
97%
of
uranium
in
a
rod
cannot
be
used
and
 becomes
waste
that
is
s8ll
radioac8ve
 Radioac8vity
will
con8nue
for
1000’s
of
years
 Most
rods
currently
stored
on‐site,
under
water,
to
 prevent
leakage
of
radia8on
(“wet
storage”)
 Some
is
kept
in
lead,
concrete,
and
steel
lined
drums
 (“dry
storage”)
 Geologic
isolaHon:
storage
of
radioac8ve
waste
deep
 beneath
the
ground
in
stable
bedrock
caverns
 –  Dangers:
need
to
isolate
from
groundwater,
biota,
keep
safe
 from
earthquakes,
provide
safe
transport
to
site
 Lecture
11
–
Energy,
Impacts,
and
Alterna8ves
 30
 Biomass
Energy
 •  Biomass:
organic
material
that
makes
upliving
and
 recently
deceased
organisms
(plants
and
animals)
 Lecture
11
–
Energy,
Impacts,
and
Alterna8ves
 31
 Rising
Popularity
of
Ethanol
and
 Biodiesel
 •  •  Ethanol:
Same
alcohol
as
in
booze;
made
in
a
process
 similar
to
making
beer
(biomass
fermenta8on)
 Biodiesel:
diesel‐like
fuel
produced
from
vegetable
 oil
mixed
with
ethanol
 Lecture
11
–
Energy,
Impacts,
and
Alterna8ves
 Figure 16.19 Figure 16.20 32
 Biomass
Fuel
Environmental
Benefits
 •  Essen8ally
carbon
neutral

CO2
is
released,
 but
“captured”
by
the
next
crop
 •  Would
therefore
reduce
NET
carbon
flux
 •  Generally
produce
fewer
addi8onal
pollutants
 •  Biomass
is
geographically
widespread,
 meaning
that
rural
and
developing
na8ons
 could
rely
less
on
imported
fuel
 •  May
be
possible
in
future
to
use
enzymes
to
 produce
cellulosic
ethanol
from
waste
 products
and
algae
 Lecture
11
–
Energy,
Impacts,
and
Alterna8ves
 33
 Biomass
Fuel
Environmental
Drawbacks
 •  Only
carbon‐neutral
if
biomass
used
is
 harvested
sustainably

not
carbon‐ neutral
if
deforesta8on
is
the
key
input
 •  Also
not
carbon‐neutral
if
the
energy
 required
to
harvest
(trucks
and
tractors)
 and
refine
fuel
is
taken
into
considera8on
 •  Biomass
fuels
usually
grown
in
 monoculture
and
take
away
arable
land
 from
food
crops
 •  EROI
only
~
1.5:1
 Lecture
11
–
Energy,
Impacts,
and
Alterna8ves
 34
 “New”
Renewables
 •  New
because:

 –  Not
yet
widely
used
 –  Technologies
for
harnessing
energy
with
these
 methods
s8ll
developing
 –  Future
role
likely
to
be
much
larger
 1.  Power
genera8on:
wind,
solar,
8dal
to
 produce
electricity
 2.  Hea8ng:
solar
and
geothermal
for
hea8ng
 3.  Fuel:
hydrogen
and
biofuels
 Lecture
11
–
Energy,
Impacts,
and
Alterna8ves
 35
 Next
Week:
Last
Class
 1.  We
will
finish
up
talking
about
alterna8ve
energy.
 
 2.  I
will
briefly
discuss
the
final
exam.

I
am
going
to
 post
an
exam
from
2
years
ago
(without
the
 answers).

The
exam
“review”
will
be
en8rely
run
 by
your
ques8ons.

 3.  We
will
have
a
guest
speaker
(Nathan
Fidler;
a
TA
 for
this
course)
who
will
bring
together
aspects
of
 economic,
poli8cal,
and
scien8fic
factors
for
a
 sustainable
environment.

 Lecture
11
–
Energy,
Impacts,
and
Alterna8ves
 36
 ...
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This note was uploaded on 02/29/2012 for the course ENVIRONMEN eesa01 taught by Professor Mitchel during the Fall '11 term at University of Toronto- Toronto.

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