LECTURE8-Hydro

advertisement
Hydropower energy
1
B.C.
Hydropower used by the Greeks to turn water wheels for
grinding wheat into flour, more than 2,000 years ago.
Mid1770s
French hydraulic and military engineer Bernard Forest de
Bélidor wrote Architecture Hydraulique, a four-volume work
describing vertical- and horizontal-axis machines.
1775
U.S. Army Corps of Engineers founded, with establishment of
Chief Engineer for the Continental Army.
1880
Michigan's Grand Rapids Electric Light and Power Company,
generating electricity by dynamo belted to a water turbine at
the Wolverine Chair Factory, lit up 16 brush-arc lamps.
1881
Niagara Falls city street lamps powered by hydropower.
1882
World's first hydroelectric power plant began operation on the
Fox River in Appleton, Wisconsin.
1886
About 45 water-powered electric plants in the U.S. and
Canada.
1887
San Bernardino, Ca., opens first hydroelectric plant in the west.
1889
Two hundred electric plants in the U.S. use waterpower for
some or all generation.
1901
First Federal Water Power Act.
1907
Hydropower provided 15% of U.S. electrical generation.
1920
Hydropower provided 25% of U.S. electrical generation.
Federal Power Act establishes Federal Power Commission
authority to issue licenses for hydro development on public
lands.
1937
Bonneville Dam, first Federal dam, begins operation on the
Columbia River. Bonneville Power Administration established.
1940
Hydropower provided 40% of electrical generation.
Conventional capacity tripled in United States since 1920.
1980
Conventional capacity nearly tripled in United States since
1940.
2003
About 10% of U.S. electricity comes from hydropower. Today,
there is about 80,000 MW of conventional capacity and 18,000 2
MW of pumped storage.
Historical Growth of Hydroelectric power:
 Currently Hydro power is 7% of the total US Energy
Budget. This has been going decreasing with time
 This varies considerably with region in the US due to
the availability of freely flowing streams
 Dam building really was initiated in the 1930's as part
of a public works program to combat the depression
 Low cost per kWh caused exponential
increase of dam building from 1950-1970
 Since 1970 hydroproduction has leveled off and
therefore becomes an increasingly smaller
percentage of the US energy budget.
Hydropower is a natural renewable energy
source
3
 Hydropower production is sensitive to secular
evolution of weather; seasonal snowpacks, etc, etc.
Long term droughts (10 years or so) seem to occur
frequently in the West
 About 30% of the hydropotential in the US has been
tapped to date
Why is Hydro so attractive?
 BECAUSE ITS CHEAP! for the consumer average
price is around 4 cents per kWh - this is 3 times
less than the national average!
 Low cost to the consumer reflect relatively low
operating costs of the Hydro Facility. Most of the
cost is in building the dam
 Operating costs about 0.6 cents per kWh
 Coal Plant averages around 2.2 cents per
kWh which reflects costs of mining, transport and
distribution.
4
How hydropower works?
Hydrocycle:
Because the water cycle is an
endless, constantly recharging
system, hydropower is
considered a renewable energy
5
Energy density in stored elevated water is high
one liter of water per second on a turbine
generates 720 watts of power. If this power can be
continuously generated for 24 hours per day for
one month then the total number of kWh per
month is then:
720 watts x 24 hours/day x 30 days/month
= 518 kWh/month.
Power generating capacity is directly proportional
to the height the water falls. For example, for a fall
of only 3 m, 30 times less electricity would be
generated (e.g. 17 Kwh/month) - but this is just
for a miniscule flow rate of 1 kg/sec.
6
Types of Hydropower Plants
 impoundment,
 diversion,
 pumped storage
Impoundment
The most common type of hydroelectric power plant is an
impoundment facility. An impoundment facility, typically a
large hydropower system, uses a dam to store river water
in a reservoir. Water released from the reservoir flows
through a turbine, spinning it, which in turn activates a
generator to produce electricity. The water may be
released either to meet changing electricity needs or to
maintain a constant reservoir level.
7
Diversion
A diversion, sometimes called run-of-river, facility
channels a portion of a river through a canal or
penstock. It may not require the use of a dam.
The Tazimina project in Alaska is an example of a
diversion hydropower plant. No dam was required.
8
Pumped Storage
When the demand for electricity is low, a pumped storage
facility stores energy by pumping water from a lower
reservoir to an upper reservoir. During periods of high
electrical demand, the water is released back to the lower
reservoir to generate electricity
9
10
Sizes of Hydroelectric Power Plants
Facilities range in size from large power plants that
supply many consumers with electricity to small and
micro plants that individuals operate for their own
energy needs or to sell power to utilities.
Large Hydropower – capacity of more than 30 MW
Small Hydropower – capacity 100 kW – 30 MW
Micro Hydropower - capacity < 100 kW
.
11
Hydro Power – Some Facts
Big range in capacity and size
 power capacity – 1 kWe to 12000 MWe
 hydraulic head < 1 m to 1500 m (from low-head to
high-head)
 largest earth dam height – 300 m (Rogun, Tajikistan)
 largest reinforced concrete dam height– 285m
(Switzerland), will be in China
 reservoir volume – >106 m3 (Uganda)
 reservoir area – 9,600 km2 (La Grande complex,
Quebec)
 hydraulic head – 1 m to 1500 m (S. Fiorano, Italy)
12
13
Potential for hydropower development in selected
countries based on technical potential and economic
potential in today’s energy markets
14
Capacities of some large dams:
Grand Coulee
John Day
Niagara (NY)
The Dalles
Chief Joseph
McNary
Hoover
Glen Canyon
1942
1969
1961
1957
1956
1954
1936
1964
6500 MW
2200 MW
2000 MW
1800 MW
1500 MW
1400 MW
1345 MW
950 MW
15
Impact of Catalysis on
Energy and Fuel
Production
A Look into the Future
Impact
16
A Few Remarks on
Energy
 Energy is the only world
currency
 Energy systems has a social
impact
 Refinery & Petrochemical
technologies have battery
limits
 Social awareness of the impact
on environment and health
17
Past, Present and Future…….
Which possible futures?
Scenario?????
18
19
POWER GENERATION
Coal fuelled power plants:
Emission: CO2, SO2, NOx, particulates
SELECTIVE CATALYTIC REDUCTION OF NOX
20
Transportation fuels
-
gasoline
Diesel fuel
jetfuel (kerosene fraction)
synthetic gasoline (Fisher-Tropsch)
synthetic Diesel (Fisher-Tropsch)
biodiesel
natural gas (NG)
SNG (synthetic natural gas)
LPG (liquified Petroleum Gas)
(mixture of propane and butane)
E85 (85% gasoline and 15% ethanol)
(fuel-flexible vehicles)
ethanol
methanol
hydrogen
21
Fuel type
MJ/l
BTU/US
gal
Research
octane
number (RON)
Naphthalene
47.14
169,100
90
Diesel
40.9
147,000
25(*)
Gasoline
32.0
125,000
91–98
Gasohol (10% ethanol + 90%gasoline)
28.06
120,900
93/94
LPG
22.16
95,475
115
Ethanol
19.59
84,400
129
Methanol
14.57
62,800
123
22
23
24
25
26
27
Representation of various structures found in gasoline
28
Gasoline reforming is the important process of altering the
composition of gasoline to achieve a higher octane rating.
As shown above, gasoline is a complex mixture of
hydrocarbons, generally falling in the range of C6-C10, and
different mixtures have different octane ratings. In order for
refineries to produce gasoline with a consistent octane
rating when the composition of the crude may be highly
variable, catalytic reforming is one of the final step in
gasoline synthesis.
Upgrading by reforming may be accomplished, in part, by
an increase in volatility (reduction of molecular size) or by
the conversion of n-paraffins to isoparaffins, olefins, and
aromatics, and of naphthenes (cycloalkanes) to aromatics.
29
30
31
Download