Concentrated Solar Power
Content
Concentrated solar power
largest CSP Project in the world has been installed in Abu
Dhabi, by Masdar.[5]
CSP growth is expected to continue at a fast pace. As of
January 2014, Spain had a total capacity of 2,204 MW
making this country the world leader in CSP. Interest is
also notable in North Africa and the Middle East, as well
as India and China. The global market has been dominated by parabolic-trough plants, which account for 90%
of CSP plants.[4]
CSP is not to be confused with concentrated photovoltaics
(CPV). In CPV, the concentrated sunlight is converted
directly to electricity via the photovoltaic effect.
The PS10 Solar Power Plant concentrates sunlight from a field
of heliostats onto a central solar power tower.
1 History
A legend has it that Archimedes used a “burning glass”
to concentrate sunlight on the invading Roman fleet and
repel them from Syracuse. In 1973 a Greek scientist,
Dr. Ioannis Sakkas, curious about whether Archimedes
could really have destroyed the Roman fleet in 212 BC,
lined up nearly 60 Greek sailors, each holding an oblong
mirror tipped to catch the sun’s rays and direct them at a
tar-covered plywood silhouette 160 feet away. The ship
caught fire after a few minutes; however, historians continue to doubt the Archimedes story.[6]
Part of the 354 MW SEGS solar complex in northern San
Bernardino County, California.
In 1866, Auguste Mouchout used a parabolic trough to
produce steam for the first solar steam engine. The first
patent for a solar collector was obtained by the Italian
Alessandro Battaglia in Genoa, Italy, in 1886. Over
the following years, inventors such as John Ericsson and
Frank Shuman developed concentrating solar-powered
devices for irrigation, refrigeration, and locomotion. In
1913 Shuman finished a 55 HP parabolic solar thermal
energy station in Maadi, Egypt for irrigation.[7][8][9][10]
The first solar-power system using a mirror dish was built
by Dr. R.H. Goddard, who was already well known for
his research on liquid-fueled rockets and wrote an article
in 1929 in which he asserted that all the previous obstacles had been addressed.[11]
Concentrated solar power (also called concentrating
solar power, concentrated solar thermal, and CSP)
systems generate solar power by using mirrors or lenses
to concentrate a large area of sunlight, or solar thermal
energy, onto a small area. Electricity is generated when
the concentrated light is converted to heat, which drives
a heat engine (usually a steam turbine) connected to an
electrical power generator or powers a thermochemical
reaction (experimental as of 2013).[1][2][3]
CSP is being widely commercialized and the CSP market has seen about 740 MW of generating capacity added
between 2007 and the end of 2010. More than half of
this (about 478 MW) was installed during 2010, bringing the global total to 1095 MW. Spain added 400 MW
in 2010, taking the global lead with a total of 632 MW,
while the US ended the year with 509 MW after adding
78 MW, including two fossil–CSP hybrid plants.[4] The
Middle East is also ramping up their plans to install CSP
based projects and as a part of that Plan, Shams-I the
Professor Giovanni Francia (1911–1980) designed and
built the first concentrated-solar plant, which entered into
operation in Sant'Ilario, near Genoa, Italy in 1968. This
plant had the architecture of today’s concentrated-solar
plants with a solar receiver in the center of a field of solar
collectors. The plant was able to produce 1 MW with superheated steam at 100 bar and 500 °C.[12] The 10 MW
Solar One power tower was developed in Southern Cali1
2
2
CURRENT TECHNOLOGY
fornia in 1981, but the parabolic-trough technology of the
nearby Solar Energy Generating Systems (SEGS), begun
in 1984, was more workable. The 354 MW SEGS is still
the largest solar power plant in the world, and will remain
so until the 390 MW Ivanpah power tower project comes
online.
2
Current technology
CSP is used to produce electricity (sometimes called solar thermoelectricity, usually generated through steam).
Concentrated-solar technology systems use mirrors or
lenses with tracking systems to focus a large area of sunlight onto a small area. The concentrated light is then Parabolic trough at a plant near Harper Lake, California
used as heat or as a heat source for a conventional power
plant (solar thermoelectricity). The solar concentrators
used in CSP systems can often also be used to provide
industrial process heating or cooling, such as in solar air- mercial parabolic trough plant are representative, alongside with Plataforma Solar de Almería's SSPS-DCS test
conditioning.
facilities in Spain.[20]
Concentrating technologies exist in five common forms,
namely parabolic trough, enclosed trough, dish Stirlings, concentrating linear Fresnel reflector, and solar
power tower.[13] Although simple, these solar concen- 2.1.1 Enclosed trough
trators are quite far from the theoretical maximum
concentration.[14][15] For example, the parabolic-trough
concentration gives about 1/3 of the theoretical maxi- Enclosed trough systems are used to produce process
mum for the design acceptance angle, that is, for the same heat. The design encapsulates the solar thermal system
overall tolerances for the system. Approaching the theo- within a greenhouse-like glasshouse. The glasshouse creretical maximum may be achieved by using more elabo- ates a protected environment to withstand the elements
that can negatively impact reliability and efficiency of
rate concentrators based on nonimaging optics.[16]
the solar thermal system.[21] Lightweight curved solarDifferent types of concentrators produce different peak reflecting mirrors are suspended from the ceiling of the
temperatures and correspondingly varying thermody- glasshouse by wires. A single-axis tracking system posinamic efficiencies, due to differences in the way that they tions the mirrors to retrieve the optimal amount of suntrack the sun and focus light. New innovations in CSP light. The mirrors concentrate the sunlight and focus it on
technology are leading systems to become more and more a network of stationary steel pipes, also suspended from
cost-effective.[17]
the glasshouse structure.[22] Water is carried throughout
the length of the pipe, which is boiled to generate steam
when intense solar radiation is applied. Sheltering the
2.1 Parabolic trough
mirrors from the wind allows them to achieve higher temperature rates and prevents dust from building up on the
Main article: Parabolic trough
mirrors.[21]
A parabolic trough consists of a linear parabolic reflector
that concentrates light onto a receiver positioned along the
reflector’s focal line. The receiver is a tube positioned directly above the middle of the parabolic mirror and filled
with a working fluid. The reflector follows the sun during the daylight hours by tracking along a single axis. A
working fluid (e.g. molten salt[18] ) is heated to 150–350
°C (423–623 K (302–662 °F)) as it flows through the receiver and is then used as a heat source for a power generation system.[19] Trough systems are the most developed
CSP technology. The Solar Energy Generating Systems
(SEGS) plants in California, the world’s first commercial
parabolic trough plants, Acciona’s Nevada Solar One near
Boulder City, Nevada, and Andasol, Europe’s first com-
2.2 Fresnel reflectors
Main article: Compact Linear Fresnel Reflector
Fresnel reflectors are made of many thin, flat mirror strips
to concentrate sunlight onto tubes through which working
fluid is pumped. Flat mirrors allow more reflective surface in the same amount of space as a parabolic reflector,
thus capturing more of the available sunlight, and they are
much cheaper than parabolic reflectors. Fresnel reflectors
can be used in various size CSPs.[23][24]
3
but they offer higher efficiency and better energy storage capability. The Solar Two in Daggett, California and
the CESA-1 in Plataforma Solar de Almeria Almeria,
Spain, are the most representative demonstration plants.
The Planta Solar 10 (PS10) in Sanlucar la Mayor, Spain,
is the first commercial utility-scale solar power tower in
the world. eSolar's 5 MW Sierra SunTower, located in
Lancaster, California, is the only CSP tower facility operating in North America. The National Solar Thermal
Test Facility, NSTTF located in Albuquerque, NM, is an
experimental solar thermal test facility with a heliostat
field capable of producing 6 MW.
3 Deployment around the world
A dish Stirling
2.3
Dish Stirling
Main article: Dish Stirling
A dish Stirling or dish engine system consists of a standalone parabolic reflector that concentrates light onto a receiver positioned at the reflector’s focal point. The reflector tracks the Sun along two axes. The working fluid in
the receiver is heated to 250–700 °C (523–973 K (482–
1,292 °F)) and then used by a Stirling engine to generate power.[19] Parabolic-dish systems provide high solarto-electric efficiency (between 31% and 32%), and their
modular nature provides scalability. The Stirling Energy
Systems (SES), United Sun Systems (USS) and Science
Applications International Corporation (SAIC) dishes at
UNLV, and Australian National University's Big Dish in
Canberra, Australia are representative of this technology.
As of 2008, The world record for solar to electric efficiency was set at 31.25% by SES dishes at the National
Solar Thermal Test Facility (NSTTF)[25] . The SES installation in Maricopa, Phoenix was the largest Stirling
Dish power installation in the world until it was sold to
United Sun Systems. Subsequently, larger parts of the
installation have been moved to China as part of the huge
energy demand.
2.4
Solar power tower
Main articles: List of solar thermal power stations and
Solar power by country
1,000
2,000
3,000
4,000
1984
1990
1995
2000
2005
2010
Worldwide CSP capacity since 1984 in MW
The commercial deployment of CSP plants started by
1984 in the US with the SEGS plants until 1990 when
the last SEGS plant was completed. From 1991 to 2005
no CSP plants were built anywhere in the world.
In 2013, worldwide installed capacity increased by 36
percent or nearly 0.9 gigawatt to more than 3.4 GW.
Spain and the United States remained the global leaders,
while the number of countries with installed CSP were
growing. There is a notable trend towards developing
countries and regions with high solar radiation. Global
installed CSP-capacity has increased nearly tenfold since
2004 and grew at an average of 50 percent per year during
the last five years.[26]:51
4 Efficiency
Main article: Solar power tower
A solar power tower consists of an array of dual-axis
tracking reflectors (heliostats) that concentrate sunlight
on a central receiver atop a tower; the receiver contains a
fluid deposit, which can consist of sea water. The working
fluid in the receiver is heated to 500–1000 °C (773–1,273
K (932–1,832 °F)) and then used as a heat source for
a power generation or energy storage system.[19] Powertower development is less advanced than trough systems,
The conversion efficiency η of the incident solar radiation
into mechanical work − without considering the ultimate
conversion step into electricity by a power generator − depends on the thermal radiation properties of the solar receiver and on the heat engine (e.g. steam turbine). Solar
irradiation is first converted into heat by the solar receiver
with the efficiency ηReceiver and subsequently the heat is
converted into work by the heat engine with the efficiency
ηCarnot , using Carnot’s principle.[29][30] For a solar re-
4
5
COSTS
ceiver providing a heat source at temperature TH and a The graph shows that the overall efficiency does not inheat sink at room temperature T°, the overall conversion crease steadily with the receiver’s temperature. Although
efficiency can be calculated as follows:
the heat engine’s efficiency (Carnot) increases with higher
temperature, the receiver’s efficiency does not. On the
contrary, the receiver’s efficiency is decreasing, as the
amount of energy it cannot absorb (Q ₒ ) grows by the
η = ηReceiver · ηCarnot
fourth power as a function of temperature. Hence, there
T0
is a maximum reachable temperature. When the receiver
ηCarnot = 1 −
TH
efficiency is null (blue curve on the figure below), T ₐₓ is:
( )0.25
Qabsorbed − Qlost
Tmax = IC
σ
ηReceiver =
Qsolar
There is a temperature Tₒ for which the efficiency is
where Qsolar , Qabsorbed , Qlost are
respectively the incoming solar flux
and the fluxes absorbed and lost by
the system solar receiver.
maximum, i.e. when the efficiency derivative relative to
the receiver temperature is null:
dη
(Topt ) = 0
dTH
For a solar flux I (e.g. I = 1000 W/m2 ) concentrated C
times with an efficiency ηOptics on the system solar re- Consequently, this leads us to the following equation:
ceiver with a collecting area A and an absorptivity α :
Qsolar = ηOptics ICA
5
4
Topt
− (0.75T 0 )Topt
−
T 0 IC
=0
4σ
Solving this equation numerically allows us to obtain the
For simplicity’s sake, one can assume that the losses are optimum process temperature according to the solar cononly radiative ones (a fair assumption for high tempera- centration ratio C (red curve on the figure below)
tures), thus for a reradiating area A and an emissivity ϵ
applying the Stefan-Boltzmann law yields:
Qabsorbed = αQsolar
4
Qlost = AϵσTH
Simplifying these equations by considering perfect optics
( ηOptics = 1), collecting and reradiating areas equal and
maximum absorptivity and emissivity ( α = 1, ϵ = 1) then
substituting in the first equation gives
η=
(
) (
)
4
σTH
T0
1−
· 1−
IC
TH
5 Costs
As of 9 September 2009, the cost of building a CSP station was typically about US$2.50 to $4 per watt,[31] while
the fuel (the sun’s radiation) is free. Thus a 250 MW CSP
station would have cost $600–1000 million to build. That
works out to $0.12 to 0.18 USD/kWh.[31] New CSP stations may be economically competitive with fossil fuels.
Nathaniel Bullard, a solar analyst at Bloomberg New Energy Finance, has calculated that the cost of electricity
at the Ivanpah Solar Power Facility, a project under construction in Southern California, will be lower than that
from photovoltaic power and about the same as that from
natural gas.[32] However, in November 2011, Google
announced that they would not invest further in CSP
projects due to the rapid price decline of photovoltaics.
5
Google invested US$168 million on BrightSource.[33][34]
IRENA has published on June 2012 a series of studies
titled: “Renewable Energy Cost Analysis”. The CSP
study shows the cost of both building and operation of
CSP plants. Costs are expected to decrease, but there are
insufficient installations to clearly establish the learning
curve. As of March 2012, there were 1.9 GW of CSP
installed, with 1.8 GW of that being parabolic trough.[35]
6
6.1
Incentives
Spain
7 Future
A study done by Greenpeace International, the European Solar Thermal Electricity Association, and the
International Energy Agency's SolarPACES group investigated the potential and future of concentrated solar
power. The study found that concentrated solar power
could account for up to 25% of the world’s energy needs
by 2050. The increase in investment would be from
2 billion euros worldwide to 92.5 billion euros in that
time period.[41] Spain is the leader in concentrated solar power technology, with more than 50 governmentapproved projects in the works. Also, it exports its technology, further increasing the technology’s stake in energy worldwide. Because the technology works best with
areas of high insolation (solar radiation), experts predict
the biggest growth in places like Africa, Mexico, and the
southwest United States. It indicates that the thermal
storage systems based in nitrates (calcium, potassium,
sodium,...) will make the CSP plants more and more
profitable. The study examined three different outcomes
for this technology: no increases in CSP technology, investment continuing as it has been in Spain and the US,
and finally the true potential of CSP without any barriers
on its growth. The findings of the third part are shown in
the table below:
Solar-thermal electricity generation is eligible for feed-in
tariff payments (art. 2 RD 661/2007), if the system capacity does not exceed the following limits: Systems registered in the register of systems prior to 29 September
2008: 500 MW for solar-thermal systems. Systems registered after 29 September 2008 (PV only). The capacity
limits for the different system types are re-defined during the review of the application conditions every quarter
(art. 5 RD 1578/2008, Annex III RD 1578/2008). Prior
to the end of an application period, the market caps specified for each system type are published on the website of
the Ministry of Industry, Tourism and Trade (art. 5 RD Finally, the study acknowledged how technology for CSP
1578/2008).[36]
was improving and how this would result in a drastic price
Since 27 January 2012, Spain has halted acceptance of decrease by 2050. It predicted a drop from the current
[41]
Renew projects for the feed-in-tariff.[37][38] Projects cur- range of €0.23–0.15/kwh to €0.14–0.10/kwh.
cently
the
EU
has
begun
to
look
into
developing
a
€400
rently accepted are not affected, except that a 6% tax on
feed-in-tariffs has been adopted, effectively reducing the billion ($774 billion) network of solar power plants based
in the Sahara region using CSP technology known as
feed-in-tariff.[39]
Desertec, to create “a new carbon-free network linking
Europe, the Middle East and North Africa”. The plan is
backed mainly by German industrialists and predicts pro6.2 Australia
duction of 15% of Europe’s power by 2050. Morocco is
a major partner in Desertec and as it has barely 1% of the
At the federal level, under the Large-scale Renewable En- electricity consumption of the EU, it will produce more
ergy Target (LRET), in operation under the Renewable than enough energy for the entire country with a large enEnergy Electricity Act 2000 (Cth), large scale solar ther- ergy surplus to deliver to Europe.[42]
mal electricity generation from accredited RET power
stations may be entitled to create large-scale generation Algeria has the biggest area of desert, and private
[42]
certificates (LGCs). These certificates can then be sold Algerian firm Cevital has signed up for Desertec.
and transferred to liable entities (usually electricity retail- With its wide desert (the highest CSP potential in the
ers) to meet their obligations under this tradeable certifi- Mediterranean and Middle East regions ~ about 170
cates scheme. However as this legislation is technology TWh/year) and its strategic geographical location near
neutral in its operation, it tends to favour more established Europe Algeria is one of the key countries to ensure the
RE technologies with a lower levelised cost of generation, success of Desertec project. Moreover, with the abunsuch as large scale onshore wind, rather than solar ther- dant natural-gas reserve in the Algerian desert, this will
mal and CSP.[40] At State level, renewable energy feed-in strengthen the technical potential of Algeria in acquirlaws typically are capped by maximum generation capac- ing Solar-Gas Hybrid Power Plants for 24-hour electricity in kWp, and are open only to micro or medium scale ity generation.
generation and in a number of instances are only open Other organizations expect CSP to cost $0.06(US)/kWh
to solar PV (photovoltaic) generation. This means that by 2015 due to efficiency improvements and mass prolarger scale CSP projects would not be eligible for pay- duction of equipment.[43] That would make CSP as cheap
ment for feed-in incentives in many of the State and Ter- as conventional power. Investors such as venture capitalist Vinod Khosla expect CSP to continuously reduce costs
ritory jurisdictions.
6
11
REFERENCES
and actually be cheaper than coal power after 2015.
On 9 September 2009, Bill Weihl, Google.org's greenenergy spokesperson said that the firm was conducting
research on the heliostat mirrors and gas turbine technology, which he expects will drop the cost of solar thermal
electric power to less than $0.05/kWh in 2 or 3 years.[31]
In 2009, scientists at the National Renewable Energy
Laboratory (NREL) and SkyFuel teamed to develop large
curved sheets of metal that have the potential to be 30%
less expensive than today’s best collectors of concentrated
solar power by replacing glass-based models with a silver
polymer sheet that has the same performance as the heavy
glass mirrors, but at much lower cost and weight. It also
is much easier to deploy and install. The glossy film uses Deceased Warbler burned mid-air by solar thermal power plant
several layers of polymers, with an inner layer of pure
silver.
Telescope designer Roger Angel (Univ. of Arizona) has
turned his attention to CPV, and is a partner in a company
called Rehnu. Angel utilizes a spherical concentrating
lens with large-telescope technologies, but much cheaper
materials and mechanisms, to create efficient systems.[44]
10 See also
• List of solar thermal power stations
• Concentrated photovoltaics (CPV)
• Copper in concentrating solar thermal power facilities
8
Very large scale solar power
plants
• Clean Technology Fund
• Desertec
• Luminescent solar concentrator
There are several proposals for gigawatt size, very large
scale solar power plants. They include the EuroMediterranean Desertec proposal, Project Helios in
Greece (10 gigawatt), and Ordos (2 gigawatt) in China.
A 2003 study concluded that the world could generate
2,357,840 TWh each year from very large scale solar
power plants using 1% of each of the world’s deserts.
Total consumption worldwide was 15,223 TWh/year[45]
(in 2003). The gigawatt size projects are arrays of single
plants. The largest single plant in operation is 80 MW
(SEGS VIII and SEGS IX) and the largest single plant
in construction is 370 MW (Ivanpah Solar). In 2012,
the BLM made available 97,921,069 acres of land in the
southwestern United States for solar projects, enough for
between 10,000 and 20,000 gigawatts (GW).[46]
• Photovoltaic thermal hybrid solar collector#PV/T
concentrator (CPVT) (CPVT)
• Salt evaporation pond
• Sandia National Laboratory
• SolarPACES
• Solar air conditioning
• Solar lighting
• Solar thermal collector
• Solar hot water
• Thermochemical cycle
9
Effect on wildlife
It has been noted that insects can be attracted to the bright
light caused by concentrated solar technology, and as a result birds that hunt them can be killed (burned) if the birds
fly near the point where light is being focused onto. This
can also affect raptors who hunt the birds.[47][48][49][50][51]
However, the number of bird deaths is far lower than the
hundreds of millions to billions that die annually from collisions with windows, vehicles, and power lines. [52]
• Thermoelectricity
• Total Spectrum Solar Concentrator
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[2] “Integrated Solar Thermochemical Reaction System”.
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Gets More Out of Natural Gas”. The New York Times.
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[4] Janet L. Sawin and Eric Martinot (29 September 2011).
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[5] Largest CSP Project in the World Inaugurated in Abu
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[6] Thomas W. Africa (1975). “Archimedes through the
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[7] Ken Butti, John Perlin (1980) A Golden Thread: 2500
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[13] Types of solar thermal CSP plants.
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[17] New innovations in solar thermal. Popularmechanics.com
(1 November 2008). Retrieved on 22 April 2013.
[18] Molten salt as CSP plant working fluid. (PDF) . Retrieved
on 22 April 2013.
[19] Christopher L. Martin; D. Yogi Goswami (2005). Solar
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EUROTROUGH and LS3”.
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Almería. Archived from the original on 28 September
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[21] Deloitte Touche Tohmatsu Ltd, “Energy & Resources Predictions 2012”, 2 November 2011
[22] Helman, Christopher, “Oil from the sun”, “Forbes”, 25
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[30] Aldo Steinfeld & Robert Palumbo (2001). “Solar Thermochemical Process Technology”. Encyclopedia of Physical Science & Technology, R.A. Meyers Ed. (Academic
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[31] Poornima Gupta and Laura Isensee (11 September 2009).
Carol Bishopric, ed. “Google Plans New Mirror For
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[32] Robert Glennon and Andrew M. Reeves (2010). “Solar
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[33] Google cans concentrated solar power project, Reve, 24
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[34] Google Renewable Energy Cheaper than Coal (RE<C).
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22 April 2013.
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[40] A Dangerous Obsession with Least Cost? Climate
Change, Renewable Energy Law and Emissions Trading
Prest, J. (2009) in Climate Change Law: Comparative,
Contractual and Regulatory Considerations, W. Gumley &
T. Daya-Winterbottom (eds.) Lawbook Company, ISBN
0455226342
[41] Concentrated solar power could generate 'quarter of
world’s energy' Guardian
[42] Tom Pfeiffer (23 August 2009) Europe’s Saharan power
plan: miracle or mirage? Reuters
[43] CSP and photovoltaic solar power, Reuters (23 August
2009).
[44] “Video:
Concentrating photovoltaics
by telescope design”.
SPIE Newsroom.
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[45] A Study of Very Large Solar Desert Systems with the Requirements and Benefits to those Nations Having High Solar Irradiation Potential. geni.org.
[46] Solar Resource Data and Maps. Solareis.anl.gov. Retrieved on 22 April 2013.
[47] http://www.nbcnews.com/science/environment/
burned-birds-become-new-environmental-victims-energy-quest-n184426
[48] http://www.esquire.com/blogs/news/
solar-plant-dead-birds-081914
[49] http://www.foxnews.com/science/2014/08/18/
california-weighing-bird-deaths-from-concentrated-solar-plants-as-it-considers/
[50] http://bigstory.ap.org/article/
emerging-solar-plants-scorch-birds-mid-air
[51] http://spectrum.ieee.org/energywise/green-tech/solar/
ivanpah-solar-plant-turns-birds-into-smoke-streamers
[52] http://www.west-inc.com/reports/avian_collisions.pdf
12
External links
• Concentrating Solar Power Utility
• United Sun Systems
• NREL Concentrating Solar Power Program
• Plataforma Solar de Almeria, CSP research center
• ISFOC (Institute of Concentrating Photovoltaic
Systems)
• Understanding Solar Concentrators – Technical Paper by George M. Kaplan
• Mirrors and Optics for Solar Energy – Technical article on mirrors and optics for concentrating solar by
Drs. Robert Molenaar in Solar Novus Today.
EXTERNAL LINKS
9
13
13.1
Text and image sources, contributors, and licenses
Text
• Concentrated solar power Source: http://en.wikipedia.org/wiki/Concentrated%20solar%20power?oldid=639085979 Contributors:
Rmhermen, Jdpipe, Fred Bauder, Mdupont, MichaelJanich, Mac, Glenn, Andres, Twang, Sunray, Phanly, Wizzy, Micru, Khalid hassani,
Isidore, Pbannister, Rich Farmbrough, Vsmith, Nabla, Giraffedata, Alansohn, Ahruman, Wtshymanski, Djsasso, Blaxthos, Mindmatrix,
WadeSimMiser, Vegaswikian, Payo, Srleffler, Bgwhite, Wavelength, Mrienstra, NeilenMarais, Tigalch, Sirlark, DrHok, Arthur Rubin,
Reyk, Sbyrnes321, SmackBot, Lawrencekhoo, KVDP, DLH, IstvanWolf, Thumperward, Victorgrigas, ABACA, A. B., Fotoguzzi, Ratel, Davipo, OmicronSSD, Fangfufu, P199, Mfield, HelloAnnyong, Chris55, Myasuda, Cydebot, Alaibot, Electron9, Dawnseeker2000,
TimVickers, Andrew Swallow, TikiTDO, Parsecboy, Yahp, Beagel, Charlenelieu, Cander0000, CommonsDelinker, NightFalcon90909,
Acalamari, M-le-mot-dit, DadaNeem, Whitethunder79, Pdcook, Johnfos, ICE77, Bkengland, Rdsherwood, Tri400, Aterk, E8, Malcolmxl5, Jojalozzo, Nopetro, OKBot, Cngoulimis, ImageRemovalBot, ClueBot, The Thing That Should Not Be, DumZiBoT, Damienbuie, Quidproquo2004, Mortense, Lars9e, 84user, Rehman, Bultro, Apteva, Yobot, Bunnyhop11, Anlai neu, TheThomas, AnomieBOT,
A More Perfect Onion, Materialscientist, RokerHRO, GB fan, LilHelpa, Nnivi, DataWraith, Jose ac, Martinella, Jeriee, Ruy Pugliesi,
Rbentley1a, Susisuess, Jakethequake, Mathonius, Entechsolar1, Solarenola, Unused0010, FrescoBot, SolarGuru, Mbudzi, Richbham, Xklaim, Chenopodiaceous, Arice6767, Elekhh, Sunsprite, 775852O, Bneeland1, George Plhak, Tbhotch, Jfmantis, BaSH PR0MPT, TGCP,
Paolotvl, Domesticenginerd, Enviromet, SolarJonathan, Lent1999, BardotD, Ὁ οἶστρος, H3llBot, Msrt10, Hamiltha, Rangoon11, MarcChambon, Corb555, Wintergrove, Hueck00u, JonRichfield, Miguel.baillon, Rememberway, ClueBot NG, Hasan Tushar, Alcauza, Otileunam, FlavienM, Joe Greentrees, Delusion23, Jose Manuel Buenavida, Mmarre, Jcc2011, Philua, Geometry001, Trinder67, Frohfroh,
Northamerica1000, Mark Arsten, NivZ, Kathy.mckenzie93, Jezzabub, Mepredator, Hillbillyholiday, Joeinwiki, Antoine Poliakov, Rfassbind, Lemnaminor, Rahulprabhurr, Larsvalentin, Solar Generator Reviews, Btmaxted, Ovelinha, Ender000, Samalmaairgy and Anonymous:
156
13.2
Images
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13.3
Content license
• Creative Commons Attribution-Share Alike 3.0
largest CSP Project in the world has been installed in Abu
Dhabi, by Masdar.[5]
CSP growth is expected to continue at a fast pace. As of
January 2014, Spain had a total capacity of 2,204 MW
making this country the world leader in CSP. Interest is
also notable in North Africa and the Middle East, as well
as India and China. The global market has been dominated by parabolic-trough plants, which account for 90%
of CSP plants.[4]
CSP is not to be confused with concentrated photovoltaics
(CPV). In CPV, the concentrated sunlight is converted
directly to electricity via the photovoltaic effect.
The PS10 Solar Power Plant concentrates sunlight from a field
of heliostats onto a central solar power tower.
1 History
A legend has it that Archimedes used a “burning glass”
to concentrate sunlight on the invading Roman fleet and
repel them from Syracuse. In 1973 a Greek scientist,
Dr. Ioannis Sakkas, curious about whether Archimedes
could really have destroyed the Roman fleet in 212 BC,
lined up nearly 60 Greek sailors, each holding an oblong
mirror tipped to catch the sun’s rays and direct them at a
tar-covered plywood silhouette 160 feet away. The ship
caught fire after a few minutes; however, historians continue to doubt the Archimedes story.[6]
Part of the 354 MW SEGS solar complex in northern San
Bernardino County, California.
In 1866, Auguste Mouchout used a parabolic trough to
produce steam for the first solar steam engine. The first
patent for a solar collector was obtained by the Italian
Alessandro Battaglia in Genoa, Italy, in 1886. Over
the following years, inventors such as John Ericsson and
Frank Shuman developed concentrating solar-powered
devices for irrigation, refrigeration, and locomotion. In
1913 Shuman finished a 55 HP parabolic solar thermal
energy station in Maadi, Egypt for irrigation.[7][8][9][10]
The first solar-power system using a mirror dish was built
by Dr. R.H. Goddard, who was already well known for
his research on liquid-fueled rockets and wrote an article
in 1929 in which he asserted that all the previous obstacles had been addressed.[11]
Concentrated solar power (also called concentrating
solar power, concentrated solar thermal, and CSP)
systems generate solar power by using mirrors or lenses
to concentrate a large area of sunlight, or solar thermal
energy, onto a small area. Electricity is generated when
the concentrated light is converted to heat, which drives
a heat engine (usually a steam turbine) connected to an
electrical power generator or powers a thermochemical
reaction (experimental as of 2013).[1][2][3]
CSP is being widely commercialized and the CSP market has seen about 740 MW of generating capacity added
between 2007 and the end of 2010. More than half of
this (about 478 MW) was installed during 2010, bringing the global total to 1095 MW. Spain added 400 MW
in 2010, taking the global lead with a total of 632 MW,
while the US ended the year with 509 MW after adding
78 MW, including two fossil–CSP hybrid plants.[4] The
Middle East is also ramping up their plans to install CSP
based projects and as a part of that Plan, Shams-I the
Professor Giovanni Francia (1911–1980) designed and
built the first concentrated-solar plant, which entered into
operation in Sant'Ilario, near Genoa, Italy in 1968. This
plant had the architecture of today’s concentrated-solar
plants with a solar receiver in the center of a field of solar
collectors. The plant was able to produce 1 MW with superheated steam at 100 bar and 500 °C.[12] The 10 MW
Solar One power tower was developed in Southern Cali1
2
2
CURRENT TECHNOLOGY
fornia in 1981, but the parabolic-trough technology of the
nearby Solar Energy Generating Systems (SEGS), begun
in 1984, was more workable. The 354 MW SEGS is still
the largest solar power plant in the world, and will remain
so until the 390 MW Ivanpah power tower project comes
online.
2
Current technology
CSP is used to produce electricity (sometimes called solar thermoelectricity, usually generated through steam).
Concentrated-solar technology systems use mirrors or
lenses with tracking systems to focus a large area of sunlight onto a small area. The concentrated light is then Parabolic trough at a plant near Harper Lake, California
used as heat or as a heat source for a conventional power
plant (solar thermoelectricity). The solar concentrators
used in CSP systems can often also be used to provide
industrial process heating or cooling, such as in solar air- mercial parabolic trough plant are representative, alongside with Plataforma Solar de Almería's SSPS-DCS test
conditioning.
facilities in Spain.[20]
Concentrating technologies exist in five common forms,
namely parabolic trough, enclosed trough, dish Stirlings, concentrating linear Fresnel reflector, and solar
power tower.[13] Although simple, these solar concen- 2.1.1 Enclosed trough
trators are quite far from the theoretical maximum
concentration.[14][15] For example, the parabolic-trough
concentration gives about 1/3 of the theoretical maxi- Enclosed trough systems are used to produce process
mum for the design acceptance angle, that is, for the same heat. The design encapsulates the solar thermal system
overall tolerances for the system. Approaching the theo- within a greenhouse-like glasshouse. The glasshouse creretical maximum may be achieved by using more elabo- ates a protected environment to withstand the elements
that can negatively impact reliability and efficiency of
rate concentrators based on nonimaging optics.[16]
the solar thermal system.[21] Lightweight curved solarDifferent types of concentrators produce different peak reflecting mirrors are suspended from the ceiling of the
temperatures and correspondingly varying thermody- glasshouse by wires. A single-axis tracking system posinamic efficiencies, due to differences in the way that they tions the mirrors to retrieve the optimal amount of suntrack the sun and focus light. New innovations in CSP light. The mirrors concentrate the sunlight and focus it on
technology are leading systems to become more and more a network of stationary steel pipes, also suspended from
cost-effective.[17]
the glasshouse structure.[22] Water is carried throughout
the length of the pipe, which is boiled to generate steam
when intense solar radiation is applied. Sheltering the
2.1 Parabolic trough
mirrors from the wind allows them to achieve higher temperature rates and prevents dust from building up on the
Main article: Parabolic trough
mirrors.[21]
A parabolic trough consists of a linear parabolic reflector
that concentrates light onto a receiver positioned along the
reflector’s focal line. The receiver is a tube positioned directly above the middle of the parabolic mirror and filled
with a working fluid. The reflector follows the sun during the daylight hours by tracking along a single axis. A
working fluid (e.g. molten salt[18] ) is heated to 150–350
°C (423–623 K (302–662 °F)) as it flows through the receiver and is then used as a heat source for a power generation system.[19] Trough systems are the most developed
CSP technology. The Solar Energy Generating Systems
(SEGS) plants in California, the world’s first commercial
parabolic trough plants, Acciona’s Nevada Solar One near
Boulder City, Nevada, and Andasol, Europe’s first com-
2.2 Fresnel reflectors
Main article: Compact Linear Fresnel Reflector
Fresnel reflectors are made of many thin, flat mirror strips
to concentrate sunlight onto tubes through which working
fluid is pumped. Flat mirrors allow more reflective surface in the same amount of space as a parabolic reflector,
thus capturing more of the available sunlight, and they are
much cheaper than parabolic reflectors. Fresnel reflectors
can be used in various size CSPs.[23][24]
3
but they offer higher efficiency and better energy storage capability. The Solar Two in Daggett, California and
the CESA-1 in Plataforma Solar de Almeria Almeria,
Spain, are the most representative demonstration plants.
The Planta Solar 10 (PS10) in Sanlucar la Mayor, Spain,
is the first commercial utility-scale solar power tower in
the world. eSolar's 5 MW Sierra SunTower, located in
Lancaster, California, is the only CSP tower facility operating in North America. The National Solar Thermal
Test Facility, NSTTF located in Albuquerque, NM, is an
experimental solar thermal test facility with a heliostat
field capable of producing 6 MW.
3 Deployment around the world
A dish Stirling
2.3
Dish Stirling
Main article: Dish Stirling
A dish Stirling or dish engine system consists of a standalone parabolic reflector that concentrates light onto a receiver positioned at the reflector’s focal point. The reflector tracks the Sun along two axes. The working fluid in
the receiver is heated to 250–700 °C (523–973 K (482–
1,292 °F)) and then used by a Stirling engine to generate power.[19] Parabolic-dish systems provide high solarto-electric efficiency (between 31% and 32%), and their
modular nature provides scalability. The Stirling Energy
Systems (SES), United Sun Systems (USS) and Science
Applications International Corporation (SAIC) dishes at
UNLV, and Australian National University's Big Dish in
Canberra, Australia are representative of this technology.
As of 2008, The world record for solar to electric efficiency was set at 31.25% by SES dishes at the National
Solar Thermal Test Facility (NSTTF)[25] . The SES installation in Maricopa, Phoenix was the largest Stirling
Dish power installation in the world until it was sold to
United Sun Systems. Subsequently, larger parts of the
installation have been moved to China as part of the huge
energy demand.
2.4
Solar power tower
Main articles: List of solar thermal power stations and
Solar power by country
1,000
2,000
3,000
4,000
1984
1990
1995
2000
2005
2010
Worldwide CSP capacity since 1984 in MW
The commercial deployment of CSP plants started by
1984 in the US with the SEGS plants until 1990 when
the last SEGS plant was completed. From 1991 to 2005
no CSP plants were built anywhere in the world.
In 2013, worldwide installed capacity increased by 36
percent or nearly 0.9 gigawatt to more than 3.4 GW.
Spain and the United States remained the global leaders,
while the number of countries with installed CSP were
growing. There is a notable trend towards developing
countries and regions with high solar radiation. Global
installed CSP-capacity has increased nearly tenfold since
2004 and grew at an average of 50 percent per year during
the last five years.[26]:51
4 Efficiency
Main article: Solar power tower
A solar power tower consists of an array of dual-axis
tracking reflectors (heliostats) that concentrate sunlight
on a central receiver atop a tower; the receiver contains a
fluid deposit, which can consist of sea water. The working
fluid in the receiver is heated to 500–1000 °C (773–1,273
K (932–1,832 °F)) and then used as a heat source for
a power generation or energy storage system.[19] Powertower development is less advanced than trough systems,
The conversion efficiency η of the incident solar radiation
into mechanical work − without considering the ultimate
conversion step into electricity by a power generator − depends on the thermal radiation properties of the solar receiver and on the heat engine (e.g. steam turbine). Solar
irradiation is first converted into heat by the solar receiver
with the efficiency ηReceiver and subsequently the heat is
converted into work by the heat engine with the efficiency
ηCarnot , using Carnot’s principle.[29][30] For a solar re-
4
5
COSTS
ceiver providing a heat source at temperature TH and a The graph shows that the overall efficiency does not inheat sink at room temperature T°, the overall conversion crease steadily with the receiver’s temperature. Although
efficiency can be calculated as follows:
the heat engine’s efficiency (Carnot) increases with higher
temperature, the receiver’s efficiency does not. On the
contrary, the receiver’s efficiency is decreasing, as the
amount of energy it cannot absorb (Q ₒ ) grows by the
η = ηReceiver · ηCarnot
fourth power as a function of temperature. Hence, there
T0
is a maximum reachable temperature. When the receiver
ηCarnot = 1 −
TH
efficiency is null (blue curve on the figure below), T ₐₓ is:
( )0.25
Qabsorbed − Qlost
Tmax = IC
σ
ηReceiver =
Qsolar
There is a temperature Tₒ for which the efficiency is
where Qsolar , Qabsorbed , Qlost are
respectively the incoming solar flux
and the fluxes absorbed and lost by
the system solar receiver.
maximum, i.e. when the efficiency derivative relative to
the receiver temperature is null:
dη
(Topt ) = 0
dTH
For a solar flux I (e.g. I = 1000 W/m2 ) concentrated C
times with an efficiency ηOptics on the system solar re- Consequently, this leads us to the following equation:
ceiver with a collecting area A and an absorptivity α :
Qsolar = ηOptics ICA
5
4
Topt
− (0.75T 0 )Topt
−
T 0 IC
=0
4σ
Solving this equation numerically allows us to obtain the
For simplicity’s sake, one can assume that the losses are optimum process temperature according to the solar cononly radiative ones (a fair assumption for high tempera- centration ratio C (red curve on the figure below)
tures), thus for a reradiating area A and an emissivity ϵ
applying the Stefan-Boltzmann law yields:
Qabsorbed = αQsolar
4
Qlost = AϵσTH
Simplifying these equations by considering perfect optics
( ηOptics = 1), collecting and reradiating areas equal and
maximum absorptivity and emissivity ( α = 1, ϵ = 1) then
substituting in the first equation gives
η=
(
) (
)
4
σTH
T0
1−
· 1−
IC
TH
5 Costs
As of 9 September 2009, the cost of building a CSP station was typically about US$2.50 to $4 per watt,[31] while
the fuel (the sun’s radiation) is free. Thus a 250 MW CSP
station would have cost $600–1000 million to build. That
works out to $0.12 to 0.18 USD/kWh.[31] New CSP stations may be economically competitive with fossil fuels.
Nathaniel Bullard, a solar analyst at Bloomberg New Energy Finance, has calculated that the cost of electricity
at the Ivanpah Solar Power Facility, a project under construction in Southern California, will be lower than that
from photovoltaic power and about the same as that from
natural gas.[32] However, in November 2011, Google
announced that they would not invest further in CSP
projects due to the rapid price decline of photovoltaics.
5
Google invested US$168 million on BrightSource.[33][34]
IRENA has published on June 2012 a series of studies
titled: “Renewable Energy Cost Analysis”. The CSP
study shows the cost of both building and operation of
CSP plants. Costs are expected to decrease, but there are
insufficient installations to clearly establish the learning
curve. As of March 2012, there were 1.9 GW of CSP
installed, with 1.8 GW of that being parabolic trough.[35]
6
6.1
Incentives
Spain
7 Future
A study done by Greenpeace International, the European Solar Thermal Electricity Association, and the
International Energy Agency's SolarPACES group investigated the potential and future of concentrated solar
power. The study found that concentrated solar power
could account for up to 25% of the world’s energy needs
by 2050. The increase in investment would be from
2 billion euros worldwide to 92.5 billion euros in that
time period.[41] Spain is the leader in concentrated solar power technology, with more than 50 governmentapproved projects in the works. Also, it exports its technology, further increasing the technology’s stake in energy worldwide. Because the technology works best with
areas of high insolation (solar radiation), experts predict
the biggest growth in places like Africa, Mexico, and the
southwest United States. It indicates that the thermal
storage systems based in nitrates (calcium, potassium,
sodium,...) will make the CSP plants more and more
profitable. The study examined three different outcomes
for this technology: no increases in CSP technology, investment continuing as it has been in Spain and the US,
and finally the true potential of CSP without any barriers
on its growth. The findings of the third part are shown in
the table below:
Solar-thermal electricity generation is eligible for feed-in
tariff payments (art. 2 RD 661/2007), if the system capacity does not exceed the following limits: Systems registered in the register of systems prior to 29 September
2008: 500 MW for solar-thermal systems. Systems registered after 29 September 2008 (PV only). The capacity
limits for the different system types are re-defined during the review of the application conditions every quarter
(art. 5 RD 1578/2008, Annex III RD 1578/2008). Prior
to the end of an application period, the market caps specified for each system type are published on the website of
the Ministry of Industry, Tourism and Trade (art. 5 RD Finally, the study acknowledged how technology for CSP
1578/2008).[36]
was improving and how this would result in a drastic price
Since 27 January 2012, Spain has halted acceptance of decrease by 2050. It predicted a drop from the current
[41]
Renew projects for the feed-in-tariff.[37][38] Projects cur- range of €0.23–0.15/kwh to €0.14–0.10/kwh.
cently
the
EU
has
begun
to
look
into
developing
a
€400
rently accepted are not affected, except that a 6% tax on
feed-in-tariffs has been adopted, effectively reducing the billion ($774 billion) network of solar power plants based
in the Sahara region using CSP technology known as
feed-in-tariff.[39]
Desertec, to create “a new carbon-free network linking
Europe, the Middle East and North Africa”. The plan is
backed mainly by German industrialists and predicts pro6.2 Australia
duction of 15% of Europe’s power by 2050. Morocco is
a major partner in Desertec and as it has barely 1% of the
At the federal level, under the Large-scale Renewable En- electricity consumption of the EU, it will produce more
ergy Target (LRET), in operation under the Renewable than enough energy for the entire country with a large enEnergy Electricity Act 2000 (Cth), large scale solar ther- ergy surplus to deliver to Europe.[42]
mal electricity generation from accredited RET power
stations may be entitled to create large-scale generation Algeria has the biggest area of desert, and private
[42]
certificates (LGCs). These certificates can then be sold Algerian firm Cevital has signed up for Desertec.
and transferred to liable entities (usually electricity retail- With its wide desert (the highest CSP potential in the
ers) to meet their obligations under this tradeable certifi- Mediterranean and Middle East regions ~ about 170
cates scheme. However as this legislation is technology TWh/year) and its strategic geographical location near
neutral in its operation, it tends to favour more established Europe Algeria is one of the key countries to ensure the
RE technologies with a lower levelised cost of generation, success of Desertec project. Moreover, with the abunsuch as large scale onshore wind, rather than solar ther- dant natural-gas reserve in the Algerian desert, this will
mal and CSP.[40] At State level, renewable energy feed-in strengthen the technical potential of Algeria in acquirlaws typically are capped by maximum generation capac- ing Solar-Gas Hybrid Power Plants for 24-hour electricity in kWp, and are open only to micro or medium scale ity generation.
generation and in a number of instances are only open Other organizations expect CSP to cost $0.06(US)/kWh
to solar PV (photovoltaic) generation. This means that by 2015 due to efficiency improvements and mass prolarger scale CSP projects would not be eligible for pay- duction of equipment.[43] That would make CSP as cheap
ment for feed-in incentives in many of the State and Ter- as conventional power. Investors such as venture capitalist Vinod Khosla expect CSP to continuously reduce costs
ritory jurisdictions.
6
11
REFERENCES
and actually be cheaper than coal power after 2015.
On 9 September 2009, Bill Weihl, Google.org's greenenergy spokesperson said that the firm was conducting
research on the heliostat mirrors and gas turbine technology, which he expects will drop the cost of solar thermal
electric power to less than $0.05/kWh in 2 or 3 years.[31]
In 2009, scientists at the National Renewable Energy
Laboratory (NREL) and SkyFuel teamed to develop large
curved sheets of metal that have the potential to be 30%
less expensive than today’s best collectors of concentrated
solar power by replacing glass-based models with a silver
polymer sheet that has the same performance as the heavy
glass mirrors, but at much lower cost and weight. It also
is much easier to deploy and install. The glossy film uses Deceased Warbler burned mid-air by solar thermal power plant
several layers of polymers, with an inner layer of pure
silver.
Telescope designer Roger Angel (Univ. of Arizona) has
turned his attention to CPV, and is a partner in a company
called Rehnu. Angel utilizes a spherical concentrating
lens with large-telescope technologies, but much cheaper
materials and mechanisms, to create efficient systems.[44]
10 See also
• List of solar thermal power stations
• Concentrated photovoltaics (CPV)
• Copper in concentrating solar thermal power facilities
8
Very large scale solar power
plants
• Clean Technology Fund
• Desertec
• Luminescent solar concentrator
There are several proposals for gigawatt size, very large
scale solar power plants. They include the EuroMediterranean Desertec proposal, Project Helios in
Greece (10 gigawatt), and Ordos (2 gigawatt) in China.
A 2003 study concluded that the world could generate
2,357,840 TWh each year from very large scale solar
power plants using 1% of each of the world’s deserts.
Total consumption worldwide was 15,223 TWh/year[45]
(in 2003). The gigawatt size projects are arrays of single
plants. The largest single plant in operation is 80 MW
(SEGS VIII and SEGS IX) and the largest single plant
in construction is 370 MW (Ivanpah Solar). In 2012,
the BLM made available 97,921,069 acres of land in the
southwestern United States for solar projects, enough for
between 10,000 and 20,000 gigawatts (GW).[46]
• Photovoltaic thermal hybrid solar collector#PV/T
concentrator (CPVT) (CPVT)
• Salt evaporation pond
• Sandia National Laboratory
• SolarPACES
• Solar air conditioning
• Solar lighting
• Solar thermal collector
• Solar hot water
• Thermochemical cycle
9
Effect on wildlife
It has been noted that insects can be attracted to the bright
light caused by concentrated solar technology, and as a result birds that hunt them can be killed (burned) if the birds
fly near the point where light is being focused onto. This
can also affect raptors who hunt the birds.[47][48][49][50][51]
However, the number of bird deaths is far lower than the
hundreds of millions to billions that die annually from collisions with windows, vehicles, and power lines. [52]
• Thermoelectricity
• Total Spectrum Solar Concentrator
11 References
[1] “Sunshine to Petrol”. Sandia National Laboratories. Retrieved 11 April 2013.
[2] “Integrated Solar Thermochemical Reaction System”.
U.S. Department of Energy. Retrieved 11 April 2013.
7
[3] Matthew L. Wald (10 April 2013). “New Solar Process
Gets More Out of Natural Gas”. The New York Times.
Retrieved 11 April 2013.
[4] Janet L. Sawin and Eric Martinot (29 September 2011).
“Renewables Bounced Back in 2010, Finds REN21
Global Report”. Renewable Energy World.
[5] Largest CSP Project in the World Inaugurated in Abu
Dhabi – Renew India Campaign – solar photovoltaic, Indian Solar News, Indian Wind News, Indian Wind Market. Renewindians.com (18 March 2013). Retrieved on
22 April 2013.
[6] Thomas W. Africa (1975). “Archimedes through the
Looking Glass”. The Classical World 68 (5): 305–308.
doi:10.2307/4348211. JSTOR 4348211.
[7] Ken Butti, John Perlin (1980) A Golden Thread: 2500
Years of Solar Architecture and Technology, Cheshire
Books, pp. 66–100, ISBN 0442240058.
[8] CM Meyer. From troughs to triumph: SEGS and gas.
Eepublishers.co.za. Retrieved on 22 April 2013.
[9] Cutler J. Cleveland (23 August 2008). Shuman, Frank.
Encyclopedia of Earth.
[10] Paul Collins (Spring 2002) The Beautiful Possibility.
Cabinet Magazine, Issue 6.
[11] “A New Invention To Harness The Sun” Popular Science,
November 1929
[12] Ken Butti, John Perlin (1980) A Golden Thread: 2500
Years of Solar Architecture and Technology, Cheshire
Books, p. 68, ISBN 0442240058.
[13] Types of solar thermal CSP plants.
Tomkonrad.wordpress.com. Retrieved on 22 April 2013.
[14] Julio Chaves (2008) Introduction to Nonimaging Optics,
CRC Press, ISBN 978-1420054293
[15] Roland Winston, Juan C. Miñano, Pablo G. Benitez
(2004) Nonimaging Optics, Academic Press, ISBN 9780127597515.
[16] Norton, Brian (2013). Harnessing Solar Heat. Springer.
ISBN 978-94-007-7275-5.
[17] New innovations in solar thermal. Popularmechanics.com
(1 November 2008). Retrieved on 22 April 2013.
[18] Molten salt as CSP plant working fluid. (PDF) . Retrieved
on 22 April 2013.
[19] Christopher L. Martin; D. Yogi Goswami (2005). Solar
energy pocket reference. Earthscan. p. 45. ISBN 978-184407-306-1.
[20] “Linear-focusing Concentrator Facilities: DCS, DISS,
EUROTROUGH and LS3”.
Plataforma Solar de
Almería. Archived from the original on 28 September
2007. Retrieved 29 September 2007.
[21] Deloitte Touche Tohmatsu Ltd, “Energy & Resources Predictions 2012”, 2 November 2011
[22] Helman, Christopher, “Oil from the sun”, “Forbes”, 25
April 2011
[23] Compact CLFR. Physics.usyd.edu.au (12 June 2002).
Retrieved on 22 April 2013.
[24] Ausra’s Compact Linear Fresnel Reflector (CLFR) and
Lower Temperature Approach. ese.iitb.ac.in
[25] Sandia, Stirling Energy Systems set new world record for
solar-to-grid conversion efficienc. Share.sandia.gov (12
February 2008). Retrieved on 22 April 2013.
[26] REN21 (2014). “Renewables 2014: Global Status Report”. Archived from the original on 4 September 2014.
[27] CSP Facts & Figures. Csp-world.com. Retrieved on 22
April 2013.
[28] Concentrating Solar Power. irena.org, p. 11.
[29] E. A. Fletcher (2001). “Solar thermal processing: A review”. Journal of Solar Energy Engineering 123 (2): 63.
doi:10.1115/1.1349552.
[30] Aldo Steinfeld & Robert Palumbo (2001). “Solar Thermochemical Process Technology”. Encyclopedia of Physical Science & Technology, R.A. Meyers Ed. (Academic
Press) 15: 237–256.
[31] Poornima Gupta and Laura Isensee (11 September 2009).
Carol Bishopric, ed. “Google Plans New Mirror For
Cheaper Solar Power”. Global Climate and Alternative Energy Summit. San Francisco: Reuters &
businessworld.in.
[32] Robert Glennon and Andrew M. Reeves (2010). “Solar
Energy’s Cloudy Future”. Arizona Journal of Environmental Law & Policy 91: 106.
[33] Google cans concentrated solar power project, Reve, 24
November 2011.
[34] Google Renewable Energy Cheaper than Coal (RE<C).
Google.org. Retrieved on 22 April 2013.
[35] Renewable Energy Cost Analysis – Concentrating Solar
Power. irena.org
[36] [http://web.archive.org/web/20120427001457/http:
//res-legal.de/en/search-for-countries/spain/single/land/
spanien/instrument/price-regulation-regimen-especial/
ueberblick/foerderung.html?bmu{[}lastPid{]}=
97&bmu{[}lastShow{]}=1&cHash=
0eefe5ac972c28a4b783b540f3d49b3d Feed-in tariff (Régimen Especial)]. res-legal.de (12 December
2011).
[37] Spanish government halts PV, CSP feed-in tariffs. Solarserver.com (30 January 2012). Retrieved on 22 April
2013.
[38] Spain Halts Feed-in-Tariffs for Renewable Energy. Instituteforenergyresearch.org (9 April 2012). Retrieved on
22 April 2013.
[39] Spain introduces 6% energy tax. Evwind.es (14 September 2012). Retrieved on 22 April 2013.
8
12
[40] A Dangerous Obsession with Least Cost? Climate
Change, Renewable Energy Law and Emissions Trading
Prest, J. (2009) in Climate Change Law: Comparative,
Contractual and Regulatory Considerations, W. Gumley &
T. Daya-Winterbottom (eds.) Lawbook Company, ISBN
0455226342
[41] Concentrated solar power could generate 'quarter of
world’s energy' Guardian
[42] Tom Pfeiffer (23 August 2009) Europe’s Saharan power
plan: miracle or mirage? Reuters
[43] CSP and photovoltaic solar power, Reuters (23 August
2009).
[44] “Video:
Concentrating photovoltaics
by telescope design”.
SPIE Newsroom.
doi:10.1117/2.3201107.02.
inspired
2011.
[45] A Study of Very Large Solar Desert Systems with the Requirements and Benefits to those Nations Having High Solar Irradiation Potential. geni.org.
[46] Solar Resource Data and Maps. Solareis.anl.gov. Retrieved on 22 April 2013.
[47] http://www.nbcnews.com/science/environment/
burned-birds-become-new-environmental-victims-energy-quest-n184426
[48] http://www.esquire.com/blogs/news/
solar-plant-dead-birds-081914
[49] http://www.foxnews.com/science/2014/08/18/
california-weighing-bird-deaths-from-concentrated-solar-plants-as-it-considers/
[50] http://bigstory.ap.org/article/
emerging-solar-plants-scorch-birds-mid-air
[51] http://spectrum.ieee.org/energywise/green-tech/solar/
ivanpah-solar-plant-turns-birds-into-smoke-streamers
[52] http://www.west-inc.com/reports/avian_collisions.pdf
12
External links
• Concentrating Solar Power Utility
• United Sun Systems
• NREL Concentrating Solar Power Program
• Plataforma Solar de Almeria, CSP research center
• ISFOC (Institute of Concentrating Photovoltaic
Systems)
• Understanding Solar Concentrators – Technical Paper by George M. Kaplan
• Mirrors and Optics for Solar Energy – Technical article on mirrors and optics for concentrating solar by
Drs. Robert Molenaar in Solar Novus Today.
EXTERNAL LINKS
9
13
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