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Encyclopedia > Solar updraft tower
Schematic presentation of a Solar updraft tower
Schematic presentation of a Solar updraft tower
Sustainable development Portal
This article is about a type of power plant. For other uses of the term "Solar Tower", see solar tower (disambiguation). For the use of solar energy for ventilation, see Solar chimney.

The solar updraft tower is a proposed type of renewable-energy power plant. Air is heated in a very large circular greenhouse-like structure, and the resulting convection causes the air to rise and escape through a tall tower. The moving air drives turbines, which produce electricity. A research prototype operated in Spain in the 1980s. Image File history File links Solar_updraft_tower. ... Image File history File links Solar_updraft_tower. ... Image File history File links Sustainable_development. ... For the solar heliostats based power plant technology Solar power tower For electricity power generation by solar-heated air in a chimney Solar chimney For the trademarked application of solar chimney technology in Australia, see Solar Tower For the sun observation structure see Solar tower This is a disambiguation page... It has been suggested that this article or section be merged with Solar Tower. ... Renewable energy effectively utilizes natural resources such as sunlight, wind, tides and geothermal heat, which are naturally replenished. ... A power station (also power plant) is a facility for the generation of electric power. ... The Royal Greenhouses of Laeken. ... Convection in the most general terms refers to the movement of currents within fluids (i. ... WWII era ship propulsion turbine A turbine is a rotary engine that extracts energy from a fluid flow. ... Electricity (from New Latin Ä“lectricus, amberlike) is a general term for a variety of phenomena resulting from the presence and flow of electric charge. ...

Contents

Description

The generating ability of a solar updraft power plant depends primarily on two factors: the size of the collector area and chimney height. With a larger collector area, more volume of air is warmed up to flow up the chimney; collector areas as large as 7 km in diameter have been considered. With a larger chimney height, the pressure difference increases the stack effect; chimneys as tall as 1000 m have been considered. Further, a combined increase of the collector area and the chimney height leads to massively larger productivity of the power plant. Stack effect is the ventilation in buildings and chimneys that results from thermal differences between indoor and outside temperature. ...


Heat can be stored inside the collector area greenhouse, to be used to warm the air later on. Water, with its relatively high specific heat capacity, can be filled in tubes placed under the collector increasing the energy storage as needed.[1] Impact from a water drop causes an upward rebound jet surrounded by circular capillary waves. ... Specific heat capacity, also known simply as specific heat, is the measure of the heat energy required to increase the temperature of a unit quantity of a substance by a certain temperature interval. ...


Turbines can be installed in a ring around the base of the tower, with a horizontal axis, as planned for the Australian project and seen in the diagram above; or—as in the prototype in Spain—a single vertical axis turbine can be installed inside the chimney. This article is about the machine for converting the kinetic energy in the wind into mechanical energy. ...


Solar towers do not produce carbon dioxide emissions during their operation, but are associated with the manufacture of its construction materials, particularly cement. Net energy payback is estimated to be 2-3 years.[1] Carbon dioxide is a chemical compound composed of two oxygen atoms covalently bonded to a single carbon atom. ... For other uses, see Cement (disambiguation). ...


A solar updraft tower power station would consume a significant area of land if it were designed to generate as much electricity as is produced by modern power stations using conventional technology. Construction would be most likely in hot areas with large amounts of very low-value land, such as deserts, or otherwise degraded land. ((( Look at me im king of the world. ...


A small-scale solar updraft tower may be an attractive option for remote regions in developing countries.[2][3] The relatively low-tech approach could allow local resources and labour to be used for its construction and maintenance.


History

In 1903, Spanish Colonel Isidoro Cabanyes first proposed a solar chimney power plant in the magazine "La energía eléctrica".[4] One of the earliest descriptions of a solar chimney power plant was written in 1931 by a German author, Hanns Günther. Beginning in 1975, Robert E. Lucier applied for patents on a solar chimney electric power generator; between 1978 and 1981 these patents, since expired, were granted in Australia,[5] Canada,[6] Israel,[7] and the USA.[8] Year 1931 (MCMXXXI) was a common year starting on Thursday (link will display full 1931 calendar) of the Gregorian calendar. ... Year 1975 (MCMLXXV) was a common year starting on Wednesday (link will display full calendar) of the Gregorian calendar. ... For other uses, see Patent (disambiguation). ...


Prototype in Spain

In 1982, a medium-scale working model of a solar chimney power plant was built under the direction of German engineer Jörg Schlaich in Manzanares, Ciudad Real, 150 km south of Madrid, Spain; the project was funded by the German government.[9][10] The chimney had a height of 195 metres and a diameter of 10 metres, with a collection area (greenhouse) of 46,000 m² (about 11 acres, or 244 m diameter) obtaining a maximum power output of about 50 kW. During operation, optimisation data was collected on a second-by-second basis.[11] This pilot power plant operated for approximately eight years, but "encountered severe structural instability close to the tower due to induced vortices", and was decommissioned in 1989.[12] Year 1982 (MCMLXXXII) was a common year starting on Friday (link displays the 1982 Gregorian calendar). ... Jörg Schlaich Jörg Schlaich (born 1934) is a German structural engineer. ... This page meets Wikipedias criteria for speedy deletion. ... This article is about the Spanish capital. ... Kwai Lo is Chinese slang for foreigner or ghost person. ...


Ciudad Real Torre Solar

This article or section contains information about a planned or expected power plant.
It may contain information of a speculative nature and the content may change dramatically as the construction and/or completion of the power plant approaches, and more information becomes available.

There is a proposal to construct a solar updraft tower in Ciudad Real, Spain entitled Ciudad Real Torre Solar. If built, it would be the first of its kind in the European Union[13] and would stand 750 metres tall[14] – nearly twice as tall as the current tallest structure in the EU, the Belmont TV Mast[15] – covering an area of 350 hectares.[16] It is expected to output 40 MW of electricity.[17] Image File history File links Gnome_globe_current_event. ... Ciudad Real (Spanish for: Royal City) is a city in Castilla-La Mancha, Spain. ... The Belmont transmitting station is a broadcasting and telecommunications facility, situated next to the B1225, one mile west of the village of Donington on Bain, near Market Rasen and Louth in Lincolnshire, England (grid reference TF217837). ... A hectare (symbol ha) is a unit of area, equal to 10 000 square metres, commonly used for measuring land area. ... The megawatt (symbol: MW) is a unit for measuring power corresponding to one million (106) watts. ...


Australian proposal

This article or section contains information about a planned or expected power plant.
It may contain information of a speculative nature and the content may change dramatically as the construction and/or completion of the power plant approaches, and more information becomes available.

EnviroMission has since 2001[18] proposed to build a solar updraft tower power generating station known as Solar Tower Buronga at a location near Buronga, New South Wales.[19] Technical details of the project are difficult to obtain[20] and the present status of the project is uncertain.[21] Image File history File links Gnome_globe_current_event. ... EnviroMission (ASX: EVM) is an Australian listed company. ... Buronga (34°09′S 142°11′E) is a town in New South Wales, Australia on the Murray River just over the bridge from Mildura, Victoria. ...


On 18 March 2007, the company board announced a merger with the US-based SolarMission Technologies, Inc. SolarMission is now the official Solar Tower developer.[22]


Conversion rate of solar energy to electrical energy

The solar updraft tower does not convert all the incoming solar energy into electrical energy. Many designs in the solar thermal group of collectors have higher conversion rates. The low conversion rate of the Solar Tower is balanced to some extent by the low investment cost per square metre of solar collection.[23] The major applications of solar thermal energy at present are heating swimming pools, heating water for domestic use, and space heating of buildings. ...


According to model calculations, a simple updraft power plant with an output of 200 MW would need a collector 7 kilometres in diameter (total area of about 38 km²) and a 1000-metre-high chimney.[1] One 200MW power station will provide enough electricity for around 200,000 typical households and will abate over 900,000 tons of greenhouse producing gases from entering the environment annually. The 38 km² collecting area is expected to extract about 0.5 per cent, or 5 W/m² of 1 kW/m², of the solar power that falls upon it. Note that in comparison, concentrating thermal (CSP) or photovoltaic (CPV) solar power plants have an efficiency ranging from 20-40%. Because no data is available to test these models on a large-scale updraft tower there remains uncertainty about the reliability of these calculations.[24] Look up W, w in Wiktionary, the free dictionary. ... Kwai Lo is Chinese slang for foreigner or ghost person. ... Solar thermal energy refers to the idea of harnessing solar power for practical applications from solar heating to electrical power generation. ... A solar cell, a form of photovoltaic cell, is a device that uses the photoelectric effect to generate electricity from light, thus generating solar power (energy). ... Solar thermal energy refers to the idea of harnessing solar power for practical applications from solar heating to electrical power generation. ...


The performance of an updraft tower may be degraded by factors such as atmospheric winds,[25][26] by drag induced by bracings used for supporting the chimney,[27] and by reflection off the top of the greenhouse canopy.


Location is also a factor. A Solar updraft power plant located at high latitudes such as in Canada would produce up to 85 per cent of the output of a similar plant located closer to the equator.[28]


Related and adapted ideas

  • The Vortex engine proposal replaces the physical chimney by a vortex of twisting air.
  • Floating Solar Chimney Technology proposes to keep a lightweight chimney aloft using rings of lifting balloons filled with a lighter-than-air gas.
  • The chimney could be constructed up a mountainside, using the terrain for support.[29]
  • The inverse of the solar updraft tower is the downdraft-driven energy tower. Evaporation of sprayed water at the top of the tower would cause a downdraft by cooling the air and driving wind turbines at the bottom of the tower.
  • The SCAF, Solar City Air Filtre, proposes to use the same principle but on a smaller scale with the addition of filtres to help clean the air of a city.
  • It has been proposed to use the greenhouse for food production (except near the tower were the winds would be too strong).

The concept of a Vortex Engine, proposed by Louis Michaud, aims to replace the physical chimney in the Solar chimney with a vortex of air. ... An Energy tower is a new concept for producing electrical power for consumer consumption, the brainchild of Professor Dan Zaslavsky. ...

Financial feasibility

This section discuss the classical design of a Solar updraft tower, the more exotic variations, aren't taken in too consideration here.


A solar updraft power station would require a very large initial capital outlay, which may be compensated by relatively low operating cost.[1] Like other renewable power sources there would be no cost for fuel. A disadvantage of a solar updraft tower is the much lower conversion efficiency than concentrating solar power stations have, thus requiring a larger collector area, and leading to higher cost of construction[30] and maintenance.[12] The solar power tower at Solar Two in California The solar power tower (also known as Central Tower power plants or Heliostat power plants or power towers) is a type of solar furnace using a tower to receive the focused sunlight. ...


Financial comparisons between solar updraft towers and concentrating solar technologies contrast a larger and simpler structure vs a smaller and more complex structure. The "better" of the two methods is the subject of much speculation and debate.


A Solar Tower is expected to have less of a requirement for standby capacity from traditional energy sources than wind power does. Various types of thermal storage mechanisms (such as a heat-absorbing surface material or salt water ponds) could be incorporated to smooth out power yields over the day/night cycle. Most renewable power systems (wind, solar-electrical) are variable, and a typical national electrical grid requires a combination of base, variable and on-demand power sources for stability. However, since distributed generation by intermittent power sources provides "smoothing" of the rate of change, this issue of variability can also be addressed by a large interconnected electrical supergrid, incorporating wind farms, hydroelectric, and solar power stations.[31] An example of a wind turbine. ... Distributed generation generates electricity from many small energy sources. ... Intermittent power sources are sources of power generation, primarily electricity, whose power output is either variable or intermittent. ... Wind turbines in Neuenkirchen, Dithmarschen (Germany). ... Hydroelectric dam diagram The waters of Llyn Stwlan, the upper reservoir of the Ffestiniog Pumped-Storage Scheme in north Wales, can just be glimpsed on the right. ... Solar power describes a number of methods of harnessing energy from the light of the sun. ...


There is still a great amount of uncertainty and debate on what the cost of production for electricity would be for a solar updraft tower and whether a tower (large or small) can be made profitable. Schlaich et al.[1] estimate a cost of electricity between 7 and 21 cents per kWh, but other estimates indicate that the electricity cannot possibly be cheaper than 25-35 cents per kWh.[32] No reliable electricity cost figures will exist until such time as actual data are available on a utility scale power plant, since cost predictions for a time scale of 25 years or more are unreliable.[33]


See also

Active solar is a term which refers to the use of solar energy to actively convert the energy in sunlight into other forms. ... In physics and engineering, energy conversion is any process of converting energy from one form to another. ... Future energy development, providing for the worlds future energy needs, currently faces great challenges. ... Solar panels are used in passive and active solar hot water systems Passive solar technologies convert sunlight into usable heat, cause air-movement for ventilation or cooling, or store heat for future use, without the assistance of other energy sources. ... Renewable energy effectively utilizes natural resources such as sunlight, wind, tides and geothermal heat, which are naturally replenished. ... The solar power tower at Solar Two in California The solar power tower (also known as Central Tower power plants or Heliostat power plants or power towers) is a type of solar furnace using a tower to receive the focused sunlight. ... A solar cell, made from a monocrystalline silicon wafer A solar cell or photovoltaic cell is a device that converts light energy into electrical energy. ... It has been suggested that this article or section be merged with Solar Tower. ... Sharav Sluice Energy Tower An energy tower is a method for producing electrical power for consumer consumption, the brainchild of Dr. Phillip Carlson, which has been expanded upon by Professor Dan Zaslavsky. ... A photovoltaic module is composed of individual PV cells. ... Solar power describes a number of methods of harnessing energy from the light of the sun. ... Solar power is not yet a significant source of large scale electricity generation in Australia, despite the country having a reputation for a hot dry and sunny climate that might make it ideal for utilisation. ... // With about 300 clear sunny days in a year, Indias theoretical solar power reception, just on its land area, is about 5 EWh/year (i. ... Solar thermal energy is a technology for harnessing solar energy for practical applications from solar heating to electrical power generation. ... Solar Thermal Collector Dish A solar thermal collector is a solar collector specifically intended to collect heat: that is, to absorb sunlight to provide heat. ... A backyard installation of passive single–axis trackers, DC rated at 2340 watts. ... This article is about a concept related to renewable energy, of which sustainable energy is a superset. ...

References

  1. ^ a b c d e Schlaich J, Bergermann R, Schiel W, Weinrebe G (2005). "Design of Commercial Solar Updraft Tower Systems—Utilization of Solar Induced Convective Flows for Power Generation" (PDF). Journal of Solar Energy Engineering 127 (1): 117-124. doi:10.1115/1.1823493. 
  2. ^ Onyangoa FN, Ochieng RM (0000). "The potential of solar chimney for application in rural areas of developing countries". Fuel 00 (0): 000-000. doi:10.1016/j.fuel.2006.04.029. 
  3. ^ Dai YJ, Huang HB, Wang RZ (2003). "Case study of solar chimney power plants in Northwestern regions of China". Renewable Energy 28 (8): 1295-1304. doi:10.1016/S0960-1481(02)00227-6. 
  4. ^ (Spanish) Lorenzo. "Las chimeneas solares:De una propuesta española en 1903 a la Central de Manzanares" (pdf). De Los Archivos Históricos De La Energía Solar.
  5. ^ AU patent 499934B, "Apparatus for converting Solar to Electrical Energy"
  6. ^ CA patent 1023564, "Utilization of Solar Energy"
  7. ^ IL patent 50721, "System and Apparatus for Converting Solar Heat to Electrical Energy"
  8. ^ US patent 4275309, "System for converting solar heat to electrical energy"
  9. ^ Haaf W, Friedrich K, Mayr G, Schlaich J (1983). "Solar Chimneys. Part 1: Principle and Construction of the Pilot Plant in Manzanares". International Journal of Solar Energy 2 (1): 3-20. 
  10. ^ Haaf W (1984). "Solar Chimneys - Part II: Preliminary Test Results from the Manzanares Pilot Plant". International Journal of Solar Energy 2 (2): 141-161. 
  11. ^ Schlaich J, Schiel W (2001), "Solar Chimneys", in RA Meyers (ed), Encyclopedia of Physical Science and Technology, 3rd Edition, Academic Press, London. ISBN 0-12-227410-5 downloadPDF (180 KiB)
  12. ^ a b Mills D (2004). "Advances in solar thermal electricity technology". Solar Energy 76 (1-3): 19-31. doi:10.1016/S0038-092X(03)00102-6. 
  13. ^ (Spanish) Muñoz-Lacuna, J.V.. "Ciudad Real tendrá una torre solar que doblará en alturaa las Torres Gemelas", lasprovincias.es, 2006-02-13. Retrieved on 2007-03-26. 
  14. ^ Diagrams - SkyscraperPage.com. SkyscraperPage.com (2007). Retrieved on 2007-03-27.
  15. ^ Belmont Transmitter. A.T.V (Aerials and Television). Retrieved on 2007-03-26.
  16. ^ (Spanish) Plaza, Julio. "La Torre Solar", HispaLibertas, 2006-02-28. Retrieved on 2007-03-26. 
  17. ^ (Spanish) Torre Solar de 750 metros en Ciudad Real. Urbanity.es (2006-02-13). Retrieved on 2007-03-27.
  18. ^ Davey, R (2001-08-06). New Green energy technology launches. Australian Securities Exchange. Retrieved on 2007-03-31.
  19. ^ Woody, Todd. "Tower of Power", CNN, 2006-10-02. Retrieved on 2007-03-09. 
  20. ^ Diesendorf, Mark (2007). Greenhouse Solutions with Sustainable Energy, UNSW Press, p.176.
  21. ^ Woody, Todd. "What's Next for the Aussie Solar Tower?", Business 2.0 Beta, 2006-10-26. Retrieved on 2007-03-09. 
  22. ^ Merger to Build Solar Tower Opportunities (pdf). EnvrioMission Ltd. (2007-03-18). Retrieved on 2007-10-31.
  23. ^ 3. Solar Energy SystemsPDF (1.24 MiB) Status Report on Solar Trough Power Plants (1996)
  24. ^ Pretorius JP, Kröger DG (2006). "Critical evaluation of solar chimney power plant performance". Solar Energy 80 (5): 535-544. doi:10.1016/j.solener.2005.04.001. 
  25. ^ Serag-Eldin MA (2004). "Computing flow in a solar chimney plant subject to atmospheric winds". Proceedings of the ASME Heat Transfer/Fluids Engineering Summer Conference 2004 2 B: 1153-1162. 
  26. ^ El-Haroun AA (2002). "The effect of wind speed at the top of the tower on the performance and energy generated from thermosyphon solar turbine". International Journal of Solar Energy 22 (1): 9-18. doi:10.1080/0142591021000003336. 
  27. ^ von Backström TW (2003). "Calculation of Pressure and Density in Solar Power Plant Chimneys". Journal of Solar Energy Engineering 125 (1): 127-129. doi:10.1115/1.1530198. 
  28. ^ Bilgen E, Rheault J (2005). "Solar chimney power plants for high latitudes". Solar Energy 79 (5): 449-458. doi:10.1016/j.solener.2005.01.003. 
  29. ^ US patent 7026723, "Air filtering chimney to clean pollution from a city and generate electric power"
  30. ^ Trieb, Franz; Ole Langniß and Helmut Klaiß (January-March 1997). "Solar electricity generation—A comparative view of technologies, costs and environmental impact". Solar Energy 59 (1-3): 89-99. Elsevier Science Ltd. doi:10.1016/S0038-092X(97)80946-2. Retrieved on 2007-03-30. 
  31. ^ Integration of Wind Energy into the Grid. European Wind Energy Association - EWEA (2005-2007). Retrieved on 2007-05-29.
  32. ^ ^  Zaslavsky, Dan (2006). "Energy Towers". PhysicaPlus - Online magazine of the Israel Physical Society (7). Israel Physical Society. Retrieved on 2007-03-30. 
  33. ^ Groenendaal, B.J. (July 2002). Solar Thermal Power Technologies (PDF). Monograph in the framework of the VLEEM Project. Energy research Centre of the Netherlands: ECN. Retrieved on 2007-03-30.

A digital object identifier (or DOI) is a standard for persistently identifying a piece of intellectual property on a digital network and associating it with related data, the metadata, in a structured extensible way. ... A digital object identifier (or DOI) is a standard for persistently identifying a piece of intellectual property on a digital network and associating it with related data, the metadata, in a structured extensible way. ... A digital object identifier (or DOI) is a standard for persistently identifying a piece of intellectual property on a digital network and associating it with related data, the metadata, in a structured extensible way. ... “PDF” redirects here. ... A kibibyte (a contraction of kilo binary byte) is a unit of information or computer storage, commonly abbreviated KiB (never kiB). 1 kibibyte = 210 bytes = 1,024 bytes The kibibyte is closely related to the kilobyte, which can be used either as a synonym for kibibyte or to refer to... 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March 26 is the 85th day of the year (86th in leap years) in the Gregorian calendar. ... Year 2006 (MMVI) was a common year starting on Sunday of the Gregorian calendar. ... is the 59th day of the year in the Gregorian calendar. ... Year 2007 (MMVII) is the current year, a common year starting on Monday of the Gregorian calendar and the AD/CE era in the 21st century. ... March 26 is the 85th day of the year (86th in leap years) in the Gregorian calendar. ... Year 2006 (MMVI) was a common year starting on Sunday of the Gregorian calendar. ... is the 44th day of the year in the Gregorian calendar. ... Year 2007 (MMVII) is the current year, a common year starting on Monday of the Gregorian calendar and the AD/CE era in the 21st century. ... is the 86th day of the year (87th in leap years) in the Gregorian calendar. ... 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Year 2007 (MMVII) is the current year, a common year starting on Monday of the Gregorian calendar and the AD/CE era in the 21st century. ... is the 68th day of the year (69th in leap years) in the Gregorian calendar. ... Year 2007 (MMVII) is the current year, a common year starting on Monday of the Gregorian calendar and the AD/CE era in the 21st century. ... is the 304th day of the year (305th in leap years) in the Gregorian calendar. ... “PDF” redirects here. ... MiB redirects here. ... A digital object identifier (or DOI) is a standard for persistently identifying a piece of intellectual property on a digital network and associating it with related data, the metadata, in a structured extensible way. ... A digital object identifier (or DOI) is a standard for persistently identifying a piece of intellectual property on a digital network and associating it with related data, the metadata, in a structured extensible way. ... A digital object identifier (or DOI) is a standard for persistently identifying a piece of intellectual property on a digital network and associating it with related data, the metadata, in a structured extensible way. ... A digital object identifier (or DOI) is a standard for persistently identifying a piece of intellectual property on a digital network and associating it with related data, the metadata, in a structured extensible way. ... A digital object identifier (or DOI) is a standard for persistently identifying a piece of intellectual property on a digital network and associating it with related data, the metadata, in a structured extensible way. ... Year 2007 (MMVII) is the current year, a common year starting on Monday of the Gregorian calendar and the AD/CE era in the 21st century. ... is the 89th day of the year (90th in leap years) in the Gregorian calendar. ... 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