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Industrial High Temperature
Solar Thermal
Power Plants
www.brightsourceenergy.com
Joshua E. Richardson
Definition
Industrial High Temperature Solar Thermal Power
Plants are systems for industrial scale use only that
utilize solar heat energy to power a turbine in order to
produce electricity.
Main Goals
• To successfully provide a fuel that is:
– Clean
– Efficient
– Cost-effective
• Energy used specifically for industry-scale
uses.
Overall Potential
• By using only 1% of the earth’s deserts, more clean
solar electric power could be produced than is
currently produced worldwide with fossil fuels.
• It is theoretically possible that over 90 percent of the
nation’s electricity and most of the transportation
sector’s energy needs, could be supplied by solar
thermal technology within the next 50 years.
• Estimated that by 2010, systems will exceed
5,000 MW…enough to serve needs of 7 million
people and save the equivalent of 46 million barrels
of oil each year.
How does it work?
• Five types with different models.
• All operate somewhat alike:
– Use lenses and reflectors to concentrate solar
power.
– Heat drives thermal power plant.
http://www.renewables-made-in-germany.com/en/solar-thermal-power-plants/
What happens at night?
• Power is stored during the daytime in molten salt at
approximately 1050°F
• Salt sometimes used to heat graphite which would be
used as a heat storage medium night-time
operations are possible!
• Storage of heat from solar power plants can allow
solar power plants to operate around the clock
– unique because they can generate power when it is
needed…day or night…rain or shine
Designs
•
•
•
•
•
Solar “Power Towers”
Parabolic trough
Solar Dish/Engine Systems
CSP plants
Fresnel Reflectors
http://www.solarpaces.org/
Comparison of Major Solar Thermal Technologies
(tower, dish, trough)
Power
Tower
Parabolic
Dish
Parabolic
Trough
Applications
Grid-connected
electric plants;
process heat for
industrial use.
Stand-alone small
power systems; grid
support
Grid-connected
electric plants;
process heat for
industrial use.
Advantages
Dispatchable base
load electricity; high
conversion
efficiencies; energy
storage; hybrid
(solar/fossil)
operation.
Dispatchable
electricity, high
conversion
efficiencies;
modularity; hybrid
(solar/fossil)
operation.
Dispatchable
peaking electricity;
commercially
available with 4,500
Gwh operating
experience; hybrid
(solar/fossil)
operation.
[Source: Status Report on Solar Thermal Power Plants. Pilkington Solar International GmbH: Cologne, Germany,1996.]
http://www.solardev.com/SEIA-makingelec.php
“Power Towers”
• The first large-scale solar energy project in the U.S.
– 1982
– DOE and individual corporations
• Solar plant with a field of computerized mirrors
called heliostats that follow the sun.
• Heliostats reflect rays towards
a central tower where heat is
used to produce steam.
• Steam turns a turbine like
in more traditional plants.
www.gadgetroad.com/spain-uses-worlds-first-solar-thermal-power-plant-367/
Power Towers, cont’d
• Power Tower 1- original trial.
– Success!
• Power Tower 2- 10MW second generation
station
– 1926 heliostats
– 300 ft. tower
– Power for 10,000 homes
• Discussion about a 30 to 100 MW tower in
Nevada.
Parabolic Trough
• Made of long rows of concentrating mirrors
• Only curved in one direction
• Track the sun from East to West with surface
that focuses sun’s energy
• Heat transfer fluid runs through pipe that is at
the focus of the troughs
• Heat is transferred to working fluid (usually
water) and used to power or drive turbine
Parabolic Trough
An Acciona solar thermal power plant, located south of Las Vegas.
http://www.nytimes.com/2008/03/06/business/06solar.html?_
r=1&em&ex=1205038800&en=2d73a651a7216de1&ei=5087%0A&oref=slogin
http://www.renewables-made-in-germany.com/en/solar-thermal-power-plants/
Parabolic Dish/Engine Systems
• Still under development
• Consists of parabolic shaped concentrators that
track sun in two-axis
• Cycle heat engine mounted on receiver
generates electricity, or
• sunlight heats fluid that
is transmitted to a
central engine
http://www.schott.com/newsfiles/20061109160336_SCHOTT_Memorandum_E.pdf
Political/Economic Obstacles
• Currently not economical
– high cost of building facilities needed
– currently can only lengthen the amount of time you
have energy by a few hours
– would require more high voltage DC lines to carry
the electricity from the southwestern U.S. to the
rest of the country
• Funding will be needed to bring solar thermal
electric into large scale development
Political/Economic Opportunities
• Can create 2 and ½ times as many skilled high
paying jobs as conventional power plants that
use fossil fuels
• Moderate net energy
• Moderate environmental impact
• Costs reduced with natural gas turbine backup
Technological Obstacles
• Needs back up or storage system
• Storage: the solar thermal plans would need
just 16 hours of storage to continuously
generate electricity
• Low efficiency
– increasing efficiency by 20-30% could
significantly reduce the cost of electricity
Technological Breakthroughs
• Future solar collectors will be mass-produced
using…
– lower cost flat mirrors, rather than curved troughs
– and sit low to the ground reducing wind loads
• Fast construction (1-2 years)
Land Use Issues
• Takes lots of area requiring high land use
• Works best in desert or other areas with lots of
sun
Negative Environmental Impacts
• May disturb desert areas
• Could potentially endanger wildlife
• Take up at least nine square miles of space
Positive Environmental Impacts
• No CO2 emissions
– reduces air pollution
• Less use of fossil fuel
Costs of Use
• 15 – 20 cents per kilowatt-hour (kwh)
– Comparison to wind…8 cents per kwh
• Costs to produce facility
– One-half (50%) the cost of solar power tower is
associated with mirrors that focus light on the
receivers
– Less than one-third (33%) is associated with
power cycle and heat storage
Additional Benefits
• The peak demand period - during the hottest
part of the day, when air conditioners are
running in the office and home - coincides
with the period of time when the solar thermal
power plant is at peak production
• Steam is emitted rather than greenhouse gases
Conclusions
• Solar thermal energy could lead the United
States into a renewable future.
• Cost reduction of producing solar thermal
energy could make this the most viable type
of available energy.
Bibliography
•
http://www.schott.com/newsfiles/20061109160336_SCHOTT_Memorandum_E.pdf
•
http://scitation.aip.org/getabs/servlet/GetabsServlet?prog=normal&id=JSEEDO000129000002000
141000001&idtype=cvips&gifs=yes
•
http://www.renewables-made-in-germany.com/en/solar-thermal-power-plants/
•
http://www.worldofrenewables.com/page.php?pageid=32
•
http://www.nrel.gov/csp/pdfs/35060.pdf
•
http://www.nytimes.com/2008/03/06/business/06solar.html?_r=1&em&ex=1205038800&en=2d73
a651a7216de1&ei=5087%0A&oref=slogin
•
http://www.futurepundit.com/archives/005052.html
•
http://www.news.com/Shrinking-the-cost-for-solar-power/2100-11392_3-6182947.html
•
http://peakenergy.blogspot.com/2008/03/solar-thermal-power-could-supply-most.html
•
http://media.cleantech.com/2570/ausra-and-solar-thermal-electricity
•
http://www.chiefengineer.org/content/content_display.cfm/seqnumber_content/3070.htm
•
http://www.sciam.com/article.cfm?id=a-solar-grand-plan&page=1
•
Living in the Environment (textbook)