Solar Concentrators - Revision history

Eric: Added a Category to the Page

2023-08-30T02:31:31Z

Added a Category to the Page

← Older revision		Revision as of 02:31, 30 August 2023
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	http://greenfieldsolar.com/industry.php		http://greenfieldsolar.com/industry.php

			[[Category: Optics]]

Maltfield at 20:10, 7 November 2022

2022-11-07T20:10:52Z

← Older revision		Revision as of 20:10, 7 November 2022
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	* The focal line would be approx one strip wide by whatever surface accuracy the foil has in the length direction. Uses are any that need batch high heat.		* The focal line would be approx one strip wide by whatever surface accuracy the foil has in the length direction. Uses are any that need batch high heat.
	* Extra low tech: rests frame on ground propped up by support legs to sun angle, and moved manually. This will only be practical for small versions.		* Extra low tech: rests frame on ground propped up by support legs to sun angle, and moved manually. This will only be practical for small versions.

			===See Also===
			* [[Scheffler]]

	===Links:===		===Links:===

Elifarley: Text replace - "openfarmtech.org/forum" to "forum.opensourceecology.org"

2013-07-02T22:06:39Z

Text replace - "openfarmtech.org/forum" to "forum.opensourceecology.org"

← Older revision		Revision as of 22:06, 2 July 2013
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	*The energy intercepted per acre of land is 4 megawatts.		*The energy intercepted per acre of land is 4 megawatts.
	*If overall energy conversion efficiency for that land area were 5%, then you would produce 200kW of power from that acre of insolation.		*If overall energy conversion efficiency for that land area were 5%, then you would produce 200kW of power from that acre of insolation.
	**The boundary layer turbine is proven to be at least 25% efficient for unoptimized experiments in the literature. [http://openfarmtech.org/index.php?title=Boundary_Layer_Turbine] Note that this page is missing and I cannot find the reference on the wiki, but that may well be the mechanical efficiency of the turbine, not of a steam engine utilizing it. That is very low. A normal bladed turbine is more than 60% efficient mechanically. More importantly and fundamentally the centrifugal force on a steam turbine of small size is the main limiting factor here. There is a more detailed analysis of this in the forum http://~~openfarmtech~~.org~~/forum~~/discussion/149/steam-engine .		**The boundary layer turbine is proven to be at least 25% efficient for unoptimized experiments in the literature. [http://openfarmtech.org/index.php?title=Boundary_Layer_Turbine] Note that this page is missing and I cannot find the reference on the wiki, but that may well be the mechanical efficiency of the turbine, not of a steam engine utilizing it. That is very low. A normal bladed turbine is more than 60% efficient mechanically. More importantly and fundamentally the centrifugal force on a steam turbine of small size is the main limiting factor here. There is a more detailed analysis of this in the forum http://forum.opensourceecology.org/discussion/149/steam-engine .
	**Counting overall system efficiency, 10% efficiency is easily attained. In fact it is even higher for dish stirling engines. Infinia gets 28% with the thermal-electric conversion at full sun, and the dish collectors are more than 90% efficient, the absorber is about 80%, so that leaves 20%. Low cost rankine engines using automobile supercharger turbines used for hospital electric power can get 8% or so at full sun. Note it goes down substantially at lower insolation, unlike solar panels, and this must be factored in to estimate overall system performance accurately.		**Counting overall system efficiency, 10% efficiency is easily attained. In fact it is even higher for dish stirling engines. Infinia gets 28% with the thermal-electric conversion at full sun, and the dish collectors are more than 90% efficient, the absorber is about 80%, so that leaves 20%. Low cost rankine engines using automobile supercharger turbines used for hospital electric power can get 8% or so at full sun. Note it goes down substantially at lower insolation, unlike solar panels, and this must be factored in to estimate overall system performance accurately.
	**If only half the land area is solar collectors (rest is access, etc.), then 5% is a reasonable figure. There's no reason we can't do substantially more than half.		**If only half the land area is solar collectors (rest is access, etc.), then 5% is a reasonable figure. There's no reason we can't do substantially more than half.

Elifarley: Text replace - "\[http:\/\/openfarmtech\.org\/index\.php\?title=([^] |])[ |]([^]])\]" to "$2"

2013-07-02T21:45:30Z

Text replace - "\[http:\/\/openfarmtech\.org\/index\.php\?title=([^] |]*)[ |]([^]]*)\]" to "$2"

← Older revision		Revision as of 21:45, 2 July 2013
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	==Feasibility Study==		==Feasibility Study==

	We must go through a basic feasibility study to understand the importance and potential of solar concentrator power. First, we are considering ''solar concentrators'' for solar '''electric''' power. While there are many solar electric system options available- from photovoltaics and stirling engines to Rankine cycle low temperature electrical generators and many others - we believe that solar concentrator-powered [~~http://openfarmtech.org/index.php?title=~~Boundary_Layer_Turbine boundary layer turbines] are the lowest cost, most ecological, and simplest to manufacture route - for bringing in solar energy as a '''mainstreamable source of energy for advanced cultures'''. The future of energy ''is'' solar.		We must go through a basic feasibility study to understand the importance and potential of solar concentrator power. First, we are considering ''solar concentrators'' for solar '''electric''' power. While there are many solar electric system options available- from photovoltaics and stirling engines to Rankine cycle low temperature electrical generators and many others - we believe that solar concentrator-powered [[Boundary_Layer_Turbine\|boundary layer turbines]] are the lowest cost, most ecological, and simplest to manufacture route - for bringing in solar energy as a '''mainstreamable source of energy for advanced cultures'''. The future of energy ''is'' solar.

	NOTE: Note also that solar cells do hold good promise in the future. This would be feasible, in a decentralized economic system, if solar cells are able to be produced in small scale facilities. One such technology is ribbon PV technology, extruded using an appliance-sized machine that takes only 1 kW of power (see [http://www.evergreensolar.com/app/en/technology/ Evergreen Solar] for an example). Moreover, this can be accomplished in a decentralized economic system only if the raw feedstock - solar grade silicon - can be produced in distributed locations - such as, even, [http://openfarmtech/weblog/ Factor e Farm]. Silicon is made from sand, and sand is ubiquitous. If abundant energy is available (such as solar concentrator power), then it is just a matter of procedure to produce all the solar grade silicon that is needed - and transcend the present "shortage" of pure silicon. The latter is merely an artifact of the economy of scarcity, where non-value-neutral technologies promoted by special interests dominate the landscape.		NOTE: Note also that solar cells do hold good promise in the future. This would be feasible, in a decentralized economic system, if solar cells are able to be produced in small scale facilities. One such technology is ribbon PV technology, extruded using an appliance-sized machine that takes only 1 kW of power (see [http://www.evergreensolar.com/app/en/technology/ Evergreen Solar] for an example). Moreover, this can be accomplished in a decentralized economic system only if the raw feedstock - solar grade silicon - can be produced in distributed locations - such as, even, [http://openfarmtech/weblog/ Factor e Farm]. Silicon is made from sand, and sand is ubiquitous. If abundant energy is available (such as solar concentrator power), then it is just a matter of procedure to produce all the solar grade silicon that is needed - and transcend the present "shortage" of pure silicon. The latter is merely an artifact of the economy of scarcity, where non-value-neutral technologies promoted by special interests dominate the landscape.

Elifarley: Reverted edits by Elifarley (talk) to last revision by Alphydan

2013-07-02T20:02:18Z

Reverted edits by Elifarley (talk) to last revision by Alphydan

Elifarley: Text replace - "\[http:\/\/openfarmtech\.org\/index\.php\?title=([^] ]*)\]" to "$1"

2013-07-02T19:57:22Z

Text replace - "\[http:\/\/openfarmtech\.org\/index\.php\?title=([^] ]*)\]" to "$1"

← Older revision		Revision as of 19:57, 2 July 2013
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	*Costs for solar cells that are presently available are $40/sq ft, or a factor 8 more		*Costs for solar cells that are presently available are $40/sq ft, or a factor 8 more
	*The boundary layer turbine [[Boundary_Layer_Turbine]\|material cost is negligible compared to the collector cost - $300 for the model that we are developing		*The boundary layer turbine [[Boundary_Layer_Turbine]\|material cost is negligible compared to the collector cost - $300 for the model that we are developing
	**5 kW turbine, with off-shelf generator head [~~http://openfarmtech.org/index.php?title=~~Boundary_Layer_Turbine#Bill_of_Materials:_Boundary_Layer_Turbine]] - is $600 total, plus $400 in labor = $1000 neocommercialization [http://www.p2pfoundation.net/Neocommercialization] cost		**5 kW turbine, with off-shelf generator head [[Boundary_Layer_Turbine#Bill_of_Materials:_Boundary_Layer_Turbine]]] - is $600 total, plus $400 in labor = $1000 neocommercialization [http://www.p2pfoundation.net/Neocommercialization] cost
	*Collector costs for the 5 kW turbine generator are:		*Collector costs for the 5 kW turbine generator are:
	**500 square feet => 50 sq meters => 50,000 W @10% efficiency => sufficient for 5 kW electric generation		**500 square feet => 50 sq meters => 50,000 W @10% efficiency => sufficient for 5 kW electric generation

Elifarley: Text replace - "\[http:\/\/openfarmtech\.org\/index\.php\?title=([^ ]) ([^]])\]" to "$2"

2013-07-02T19:08:43Z

Text replace - "\[http:\/\/openfarmtech\.org\/index\.php\?title=([^ ]*) ([^]]*)\]" to "$2"

Alphydan: /* Links: */

2011-10-27T16:20:30Z

Links:

← Older revision		Revision as of 16:20, 27 October 2011
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	*http://www.harbornet.com/sunflower/hong_kong.jpg		*http://www.harbornet.com/sunflower/hong_kong.jpg
	*http://www.harbornet.com/sunflower/cleveland.jpg		*http://www.harbornet.com/sunflower/cleveland.jpg
			*http://www.gses.it/pub/silvi-fresnel.pdf

	Note: dish systems are not highly [[intensively-scalable]], thus, they do not score highly on the scalability metric of [[OSE Specifications]] (See discussion page on why this is an unwarranted statement)		Note: dish systems are not highly [[intensively-scalable]], thus, they do not score highly on the scalability metric of [[OSE Specifications]] (See discussion page on why this is an unwarranted statement)

Gregortheinventor: added some info

2011-05-15T17:03:22Z

added some info

DanielRavenNest: /* Low Tech Strip Concentrator */

2011-05-15T13:20:09Z

Low Tech Strip Concentrator

← Older revision		Revision as of 13:20, 15 May 2011
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	* Target mount should allow for using various targets for different uses.		* Target mount should allow for using various targets for different uses.
	* Alternately the upper end of the polar aligned pipe can be raised or lowered for seasonal changes, but this may be too heavy to adjust for a large system. Another alternate is to angle one end of each strip vertically for seasons.		* Alternately the upper end of the polar aligned pipe can be raised or lowered for seasonal changes, but this may be too heavy to adjust for a large system. Another alternate is to angle one end of each strip vertically for seasons.
	* Counterweights are added ~~blow~~ the dish to balance the heated target.		* Counterweights are added below the dish to balance the heated target.
	* The entire system is tarped over to protect it from rain, and accidental burns when not in use. Covering some strips or parts thereof can adjust power level as needed.		* The entire system is tarped over to protect it from rain, and accidental burns when not in use. Covering some strips or parts thereof can adjust power level as needed.
	* The focal line would be approx one strip wide by whatever surface accuracy the foil has in the length direction. Uses are any that need batch high heat.		* The focal line would be approx one strip wide by whatever surface accuracy the foil has in the length direction. Uses are any that need batch high heat.

← Older revision		Revision as of 20:02, 2 July 2013
Line 51:		Line 51:
	==Feasibility Study==		==Feasibility Study==

	We must go through a basic feasibility study to understand the importance and potential of solar concentrator power. First, we are considering ''solar concentrators'' for solar '''electric''' power. While there are many solar electric system options available- from photovoltaics and stirling engines to Rankine cycle low temperature electrical generators and many others - we believe that solar concentrator-powered [[Boundary_Layer_Turbine\|boundary layer turbines]] are the lowest cost, most ecological, and simplest to manufacture route - for bringing in solar energy as a '''mainstreamable source of energy for advanced cultures'''. The future of energy ''is'' solar.		We must go through a basic feasibility study to understand the importance and potential of solar concentrator power. First, we are considering ''solar concentrators'' for solar '''electric''' power. While there are many solar electric system options available- from photovoltaics and stirling engines to Rankine cycle low temperature electrical generators and many others - we believe that solar concentrator-powered [http://openfarmtech.org/index.php?title=Boundary_Layer_Turbine boundary layer turbines] are the lowest cost, most ecological, and simplest to manufacture route - for bringing in solar energy as a '''mainstreamable source of energy for advanced cultures'''. The future of energy ''is'' solar.

	NOTE: Note also that solar cells do hold good promise in the future. This would be feasible, in a decentralized economic system, if solar cells are able to be produced in small scale facilities. One such technology is ribbon PV technology, extruded using an appliance-sized machine that takes only 1 kW of power (see [http://www.evergreensolar.com/app/en/technology/ Evergreen Solar] for an example). Moreover, this can be accomplished in a decentralized economic system only if the raw feedstock - solar grade silicon - can be produced in distributed locations - such as, even, [http://openfarmtech/weblog/ Factor e Farm]. Silicon is made from sand, and sand is ubiquitous. If abundant energy is available (such as solar concentrator power), then it is just a matter of procedure to produce all the solar grade silicon that is needed - and transcend the present "shortage" of pure silicon. The latter is merely an artifact of the economy of scarcity, where non-value-neutral technologies promoted by special interests dominate the landscape.		NOTE: Note also that solar cells do hold good promise in the future. This would be feasible, in a decentralized economic system, if solar cells are able to be produced in small scale facilities. One such technology is ribbon PV technology, extruded using an appliance-sized machine that takes only 1 kW of power (see [http://www.evergreensolar.com/app/en/technology/ Evergreen Solar] for an example). Moreover, this can be accomplished in a decentralized economic system only if the raw feedstock - solar grade silicon - can be produced in distributed locations - such as, even, [http://openfarmtech/weblog/ Factor e Farm]. Silicon is made from sand, and sand is ubiquitous. If abundant energy is available (such as solar concentrator power), then it is just a matter of procedure to produce all the solar grade silicon that is needed - and transcend the present "shortage" of pure silicon. The latter is merely an artifact of the economy of scarcity, where non-value-neutral technologies promoted by special interests dominate the landscape.
Line 63:		Line 63:
	*The energy intercepted per acre of land is 4 megawatts.		*The energy intercepted per acre of land is 4 megawatts.
	*If overall energy conversion efficiency for that land area were 5%, then you would produce 200kW of power from that acre of insolation.		*If overall energy conversion efficiency for that land area were 5%, then you would produce 200kW of power from that acre of insolation.
	**The boundary layer turbine is proven to be at least 25% efficient for unoptimized experiments in the literature. [[Boundary_Layer_Turbine]\| Note that this page is missing and I cannot find the reference on the wiki, but that may well be the mechanical efficiency of the turbine, not of a steam engine utilizing it. That is very low. A normal bladed turbine is more than 60% efficient mechanically. More importantly and fundamentally the centrifugal force on a steam turbine of small size is the main limiting factor here. There is a more detailed analysis of this in the forum http://openfarmtech.org/forum/discussion/149/steam-engine .		**The boundary layer turbine is proven to be at least 25% efficient for unoptimized experiments in the literature. [http://openfarmtech.org/index.php?title=Boundary_Layer_Turbine] Note that this page is missing and I cannot find the reference on the wiki, but that may well be the mechanical efficiency of the turbine, not of a steam engine utilizing it. That is very low. A normal bladed turbine is more than 60% efficient mechanically. More importantly and fundamentally the centrifugal force on a steam turbine of small size is the main limiting factor here. There is a more detailed analysis of this in the forum http://openfarmtech.org/forum/discussion/149/steam-engine .
	**Counting overall system efficiency, 10% efficiency is easily attained. In fact it is even higher for dish stirling engines. Infinia gets 28% with the thermal-electric conversion at full sun, and the dish collectors are more than 90% efficient, the absorber is about 80%, so that leaves 20%. Low cost rankine engines using automobile supercharger turbines used for hospital electric power can get 8% or so at full sun. Note it goes down substantially at lower insolation, unlike solar panels, and this must be factored in to estimate overall system performance accurately.		**Counting overall system efficiency, 10% efficiency is easily attained. In fact it is even higher for dish stirling engines. Infinia gets 28% with the thermal-electric conversion at full sun, and the dish collectors are more than 90% efficient, the absorber is about 80%, so that leaves 20%. Low cost rankine engines using automobile supercharger turbines used for hospital electric power can get 8% or so at full sun. Note it goes down substantially at lower insolation, unlike solar panels, and this must be factored in to estimate overall system performance accurately.
	**If only half the land area is solar collectors (rest is access, etc.), then 5% is a reasonable figure. There's no reason we can't do substantially more than half.		**If only half the land area is solar collectors (rest is access, etc.), then 5% is a reasonable figure. There's no reason we can't do substantially more than half.
	*The 200 kW obtainable per acre is comparable, on a per-acre basis, to coal power plants.		*The 200 kW obtainable per acre is comparable, on a per-acre basis, to coal power plants.
	*Coal power plant of 1 square mile - 640 acres/mile 200kW/acre ~ 100 MW output per square mile if the area was in solar concentrators. So, 10 square miles would constitue a gigawatt solar power plant. This is comparable to the area and output of coal plants.		*Coal power plant of 1 square mile - 640 acres/mile 200kW/acre ~ 100 MW output per square mile if the area was in solar concentrators. So, 10 square miles would constitue a gigawatt solar power plant. This is comparable to the area and output of coal plants.
	**A solar thermal electric plant of 177 MW on one square mile was recently installed in California - [http://ausra.com/news/releases/071105.html]]		**A solar thermal electric plant of 177 MW on one square mile was recently installed in California - [http://ausra.com/news/releases/071105.html]
	**Nuclear power plants are typically 1 square mile in size [http://www.nucleartourist.net/areas/areas.htm]		**Nuclear power plants are typically 1 square mile in size [http://www.nucleartourist.net/areas/areas.htm]
	*The 200 kW/acre is also twice the per-acre power of the most advanced Stirling engine thermal electric generators. [http://peswiki.com/index.php/Directory:Stirling_Energy_Systems]		*The 200 kW/acre is also twice the per-acre power of the most advanced Stirling engine thermal electric generators. [http://peswiki.com/index.php/Directory:Stirling_Energy_Systems]
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	**Balance of system costs should be about $5/sq ft		**Balance of system costs should be about $5/sq ft
	*Costs for solar cells that are presently available are $40/sq ft, or a factor 8 more		*Costs for solar cells that are presently available are $40/sq ft, or a factor 8 more
	*The boundary layer turbine [[Boundary_Layer_Turbine]\|material cost is negligible compared to the collector cost - $300 for the model that we are developing		*The boundary layer turbine [http://openfarmtech.org/index.php?title=Boundary_Layer_Turbine] material cost is negligible compared to the collector cost - $300 for the model that we are developing
	**5 kW turbine, with off-shelf generator head [[Boundary_Layer_Turbine#Bill_of_Materials:_Boundary_Layer_Turbine]]] - is $600 total, plus $400 in labor = $1000 neocommercialization [http://www.p2pfoundation.net/Neocommercialization] cost		**5 kW turbine, with off-shelf generator head [http://openfarmtech.org/index.php?title=Boundary_Layer_Turbine#Bill_of_Materials:_Boundary_Layer_Turbine] - is $600 total, plus $400 in labor = $1000 neocommercialization [http://www.p2pfoundation.net/Neocommercialization] cost
	*Collector costs for the 5 kW turbine generator are:		*Collector costs for the 5 kW turbine generator are:
	**500 square feet => 50 sq meters => 50,000 W @10% efficiency => sufficient for 5 kW electric generation		**500 square feet => 50 sq meters => 50,000 W @10% efficiency => sufficient for 5 kW electric generation

← Older revision		Revision as of 19:08, 2 July 2013
Line 51:		Line 51:
	==Feasibility Study==		==Feasibility Study==

	We must go through a basic feasibility study to understand the importance and potential of solar concentrator power. First, we are considering ''solar concentrators'' for solar '''electric''' power. While there are many solar electric system options available- from photovoltaics and stirling engines to Rankine cycle low temperature electrical generators and many others - we believe that solar concentrator-powered [~~http://openfarmtech.org/index.php?title=~~Boundary_Layer_Turbine boundary layer turbines] are the lowest cost, most ecological, and simplest to manufacture route - for bringing in solar energy as a '''mainstreamable source of energy for advanced cultures'''. The future of energy ''is'' solar.		We must go through a basic feasibility study to understand the importance and potential of solar concentrator power. First, we are considering ''solar concentrators'' for solar '''electric''' power. While there are many solar electric system options available- from photovoltaics and stirling engines to Rankine cycle low temperature electrical generators and many others - we believe that solar concentrator-powered [[Boundary_Layer_Turbine\|boundary layer turbines]] are the lowest cost, most ecological, and simplest to manufacture route - for bringing in solar energy as a '''mainstreamable source of energy for advanced cultures'''. The future of energy ''is'' solar.

	NOTE: Note also that solar cells do hold good promise in the future. This would be feasible, in a decentralized economic system, if solar cells are able to be produced in small scale facilities. One such technology is ribbon PV technology, extruded using an appliance-sized machine that takes only 1 kW of power (see [http://www.evergreensolar.com/app/en/technology/ Evergreen Solar] for an example). Moreover, this can be accomplished in a decentralized economic system only if the raw feedstock - solar grade silicon - can be produced in distributed locations - such as, even, [http://openfarmtech/weblog/ Factor e Farm]. Silicon is made from sand, and sand is ubiquitous. If abundant energy is available (such as solar concentrator power), then it is just a matter of procedure to produce all the solar grade silicon that is needed - and transcend the present "shortage" of pure silicon. The latter is merely an artifact of the economy of scarcity, where non-value-neutral technologies promoted by special interests dominate the landscape.		NOTE: Note also that solar cells do hold good promise in the future. This would be feasible, in a decentralized economic system, if solar cells are able to be produced in small scale facilities. One such technology is ribbon PV technology, extruded using an appliance-sized machine that takes only 1 kW of power (see [http://www.evergreensolar.com/app/en/technology/ Evergreen Solar] for an example). Moreover, this can be accomplished in a decentralized economic system only if the raw feedstock - solar grade silicon - can be produced in distributed locations - such as, even, [http://openfarmtech/weblog/ Factor e Farm]. Silicon is made from sand, and sand is ubiquitous. If abundant energy is available (such as solar concentrator power), then it is just a matter of procedure to produce all the solar grade silicon that is needed - and transcend the present "shortage" of pure silicon. The latter is merely an artifact of the economy of scarcity, where non-value-neutral technologies promoted by special interests dominate the landscape.
Line 63:		Line 63:
	*The energy intercepted per acre of land is 4 megawatts.		*The energy intercepted per acre of land is 4 megawatts.
	*If overall energy conversion efficiency for that land area were 5%, then you would produce 200kW of power from that acre of insolation.		*If overall energy conversion efficiency for that land area were 5%, then you would produce 200kW of power from that acre of insolation.
	**The boundary layer turbine is proven to be at least 25% efficient for unoptimized experiments in the literature. [~~http://openfarmtech.org/index.php?title=~~Boundary_Layer_Turbine] Note that this page is missing and I cannot find the reference on the wiki, but that may well be the mechanical efficiency of the turbine, not of a steam engine utilizing it. That is very low. A normal bladed turbine is more than 60% efficient mechanically. More importantly and fundamentally the centrifugal force on a steam turbine of small size is the main limiting factor here. There is a more detailed analysis of this in the forum http://openfarmtech.org/forum/discussion/149/steam-engine .		**The boundary layer turbine is proven to be at least 25% efficient for unoptimized experiments in the literature. [[Boundary_Layer_Turbine]\| Note that this page is missing and I cannot find the reference on the wiki, but that may well be the mechanical efficiency of the turbine, not of a steam engine utilizing it. That is very low. A normal bladed turbine is more than 60% efficient mechanically. More importantly and fundamentally the centrifugal force on a steam turbine of small size is the main limiting factor here. There is a more detailed analysis of this in the forum http://openfarmtech.org/forum/discussion/149/steam-engine .
	**Counting overall system efficiency, 10% efficiency is easily attained. In fact it is even higher for dish stirling engines. Infinia gets 28% with the thermal-electric conversion at full sun, and the dish collectors are more than 90% efficient, the absorber is about 80%, so that leaves 20%. Low cost rankine engines using automobile supercharger turbines used for hospital electric power can get 8% or so at full sun. Note it goes down substantially at lower insolation, unlike solar panels, and this must be factored in to estimate overall system performance accurately.		**Counting overall system efficiency, 10% efficiency is easily attained. In fact it is even higher for dish stirling engines. Infinia gets 28% with the thermal-electric conversion at full sun, and the dish collectors are more than 90% efficient, the absorber is about 80%, so that leaves 20%. Low cost rankine engines using automobile supercharger turbines used for hospital electric power can get 8% or so at full sun. Note it goes down substantially at lower insolation, unlike solar panels, and this must be factored in to estimate overall system performance accurately.
	**If only half the land area is solar collectors (rest is access, etc.), then 5% is a reasonable figure. There's no reason we can't do substantially more than half.		**If only half the land area is solar collectors (rest is access, etc.), then 5% is a reasonable figure. There's no reason we can't do substantially more than half.
	*The 200 kW obtainable per acre is comparable, on a per-acre basis, to coal power plants.		*The 200 kW obtainable per acre is comparable, on a per-acre basis, to coal power plants.
	*Coal power plant of 1 square mile - 640 acres/mile 200kW/acre ~ 100 MW output per square mile if the area was in solar concentrators. So, 10 square miles would constitue a gigawatt solar power plant. This is comparable to the area and output of coal plants.		*Coal power plant of 1 square mile - 640 acres/mile 200kW/acre ~ 100 MW output per square mile if the area was in solar concentrators. So, 10 square miles would constitue a gigawatt solar power plant. This is comparable to the area and output of coal plants.
	**A solar thermal electric plant of 177 MW on one square mile was recently installed in California - [http://ausra.com/news/releases/071105.html]		**A solar thermal electric plant of 177 MW on one square mile was recently installed in California - [http://ausra.com/news/releases/071105.html]]
	**Nuclear power plants are typically 1 square mile in size [http://www.nucleartourist.net/areas/areas.htm]		**Nuclear power plants are typically 1 square mile in size [http://www.nucleartourist.net/areas/areas.htm]
	*The 200 kW/acre is also twice the per-acre power of the most advanced Stirling engine thermal electric generators. [http://peswiki.com/index.php/Directory:Stirling_Energy_Systems]		*The 200 kW/acre is also twice the per-acre power of the most advanced Stirling engine thermal electric generators. [http://peswiki.com/index.php/Directory:Stirling_Energy_Systems]
Line 100:		Line 100:
	**Balance of system costs should be about $5/sq ft		**Balance of system costs should be about $5/sq ft
	*Costs for solar cells that are presently available are $40/sq ft, or a factor 8 more		*Costs for solar cells that are presently available are $40/sq ft, or a factor 8 more
	*The boundary layer turbine [~~http://openfarmtech.org/index.php?title=~~Boundary_Layer_Turbine] material cost is negligible compared to the collector cost - $300 for the model that we are developing		*The boundary layer turbine [[Boundary_Layer_Turbine]\|material cost is negligible compared to the collector cost - $300 for the model that we are developing
	**5 kW turbine, with off-shelf generator head [http://openfarmtech.org/index.php?title=Boundary_Layer_Turbine#Bill_of_Materials:_Boundary_Layer_Turbine] - is $600 total, plus $400 in labor = $1000 neocommercialization [http://www.p2pfoundation.net/Neocommercialization] cost		**5 kW turbine, with off-shelf generator head [http://openfarmtech.org/index.php?title=Boundary_Layer_Turbine#Bill_of_Materials:_Boundary_Layer_Turbine]] - is $600 total, plus $400 in labor = $1000 neocommercialization [http://www.p2pfoundation.net/Neocommercialization] cost
	*Collector costs for the 5 kW turbine generator are:		*Collector costs for the 5 kW turbine generator are:
	**500 square feet => 50 sq meters => 50,000 W @10% efficiency => sufficient for 5 kW electric generation		**500 square feet => 50 sq meters => 50,000 W @10% efficiency => sufficient for 5 kW electric generation

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	*Solar insolation on a clear day is about 1 kW/square meter		*Solar insolation on a clear day is about 1 kW/square meter
	**Considering cloud cover and day/night cycles, a place like Missouri gets 6 kWhr/square meter/day of insolation throughout the year, on average. [http://rredc.nrel.gov/solar/old_data/nsrdb/redbook/sum2/03947.txt]. You can check the insolation for your location in the uSA as well.		*Considering cloud cover and day/night cycles, a place like Missouri gets 6 kWhr/square meter/day of insolation throughout the year, on average. [http://rredc.nrel.gov/solar/old_data/nsrdb/redbook/sum2/03947.txt]. You can check the insolation for your location in the uSA as well. Other sources indicate it is less, only 4.73. (http://solardirect.com/pv/systems/gts/gts-sizing-sun-hours.html) detailed weather data is available for free here http://www.ncdc.noaa.gov/oa/ncdc.html free if you are coming from a .edu address otherwise about $20.* Good for simulations. Also there is a program distributed by Sandia labs called the Solar advisor Model. It is quite good and can be used in combination with other simulation methods to do earlier phases of the simulations (e.g. determine the sunlight present at the absorber for various types) as you can extract the data from various stages of the simulation from it in table form easily.
	*The earth intercepts 10,000 more times energy from the sun than we currently use in all fossil and nonfossil fuels today.		*The earth intercepts 10,000 more times energy from the sun than we currently use in all fossil and nonfossil fuels today.
	*The energy intercepted per acre of land is 4 megawatts.		*The energy intercepted per acre of land is 4 megawatts.
	*If overall energy conversion efficiency for that land area were 5%, then you would produce 200kW of power from that acre of insolation.		*If overall energy conversion efficiency for that land area were 5%, then you would produce 200kW of power from that acre of insolation.
	**The boundary layer turbine is proven to be at least 25% efficient for unoptimized experiments in the literature. [http://openfarmtech.org/index.php?title=Boundary_Layer_Turbine]		**The boundary layer turbine is proven to be at least 25% efficient for unoptimized experiments in the literature. [http://openfarmtech.org/index.php?title=Boundary_Layer_Turbine] Note that this page is missing and I cannot find the reference on the wiki, but that may well be the mechanical efficiency of the turbine, not of a steam engine utilizing it. That is very low. A normal bladed turbine is more than 60% efficient mechanically. More importantly and fundamentally the centrifugal force on a steam turbine of small size is the main limiting factor here. There is a more detailed analysis of this in the forum http://openfarmtech.org/forum/discussion/149/steam-engine .
	**Counting overall system efficiency, 10% efficiency is easily attained		**Counting overall system efficiency, 10% efficiency is easily attained. In fact it is even higher for dish stirling engines. Infinia gets 28% with the thermal-electric conversion at full sun, and the dish collectors are more than 90% efficient, the absorber is about 80%, so that leaves 20%. Low cost rankine engines using automobile supercharger turbines used for hospital electric power can get 8% or so at full sun. Note it goes down substantially at lower insolation, unlike solar panels, and this must be factored in to estimate overall system performance accurately.
	**If only half the land area is solar collectors (rest is access, etc.), then 5% is a reasonable figure		**If only half the land area is solar collectors (rest is access, etc.), then 5% is a reasonable figure. There's no reason we can't do substantially more than half.
	*The 200 kW obtainable per acre is comparable, on a per-acre basis, to coal power plants.		*The 200 kW obtainable per acre is comparable, on a per-acre basis, to coal power plants.
	*Coal power plant of 1 square mile - 640 acres/mile 200kW/acre ~ 100 MW output per square mile if the area was in solar concentrators. So, 10 square miles would constitue a gigawatt solar power plant. This is comparable to the area and output of coal plants.		*Coal power plant of 1 square mile - 640 acres/mile 200kW/acre ~ 100 MW output per square mile if the area was in solar concentrators. So, 10 square miles would constitue a gigawatt solar power plant. This is comparable to the area and output of coal plants.
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	**Nuclear power plants are typically 1 square mile in size [http://www.nucleartourist.net/areas/areas.htm]		**Nuclear power plants are typically 1 square mile in size [http://www.nucleartourist.net/areas/areas.htm]
	*The 200 kW/acre is also twice the per-acre power of the most advanced Stirling engine thermal electric generators. [http://peswiki.com/index.php/Directory:Stirling_Energy_Systems]		*The 200 kW/acre is also twice the per-acre power of the most advanced Stirling engine thermal electric generators. [http://peswiki.com/index.php/Directory:Stirling_Energy_Systems]
	**This is not because the advanced Stirlings are not efficient, but because there is so few of them per acre.		**This might not be because the advanced Stirlings are not efficient, but because there is so few of them per acre. This would be no different for a steam system though. A concentrator is a concentrator.


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	The weak link in the system is the boundary layer turbine itself. So far, we have heard conflicting messages on its feasibility. Scientific journals have showed 25% efficiency for a small, steam-powered boundary layer turbine. If that is true - then this is enough information to go on to take on the development of the turbine. Indeed, I found that Dan Granett ran a 16-disk, 12-inch diameter turbine successfully on compressed air to generate 4 kW of electric power. His design did not have seals, so he designed a simplified turbine, with seals - [[Boundary Layer Turbine]] - which is the design that we're working on.		The weak link in the system is the boundary layer turbine itself. So far, we have heard conflicting messages on its feasibility. Scientific journals have showed 25% efficiency for a small, steam-powered boundary layer turbine. If that is true - then this is enough information to go on to take on the development of the turbine. Indeed, I found that Dan Granett ran a 16-disk, 12-inch diameter turbine successfully on compressed air to generate 4 kW of electric power. His design did not have seals, so he designed a simplified turbine, with seals - [[Boundary Layer Turbine]] - which is the design that we're working on.

	We are interested in tracking down those researchers. One of them is Warren Rice, author of the above 25% turbine paper. He was professor of Engineering Science at Arizona State University, Tempe, AZ, when he wrote the paper in 1963. We would appreciate any help in tracking down the true story of why the boundary layer turbine has not attained wider acceptance.		We are interested in tracking down those researchers. One of them is Warren Rice, author of the above 25% turbine paper. He was professor of Engineering Science at Arizona State University, Tempe, AZ, when he wrote the paper in 1963. We would appreciate any help in tracking down the true story of why the boundary layer turbine has not attained wider acceptance. Note: it needs to be verified if this 25% figure refers to mechanical efficiency or not. If so that is the explanation; bladed turbines have more than 60% efficiency at optimal speed.

	If there is a small-scale turbine that is so efficient, why has this not been commercialized? Our research indicates that this is because much more efficient bladed turbines have been produced. However, those turbines are at least a factor of 10 times more expensive. '''''Thus, for particular applications, the boundary layer turbine may be a suitable, cost-effective option.''''' This is also the conclusion drawn on p. 35 of Rice, Warren, Transactions of the ASME, Journal of Engineering and Power, January 1965.		If there is a small-scale turbine that is so efficient, why has this not been commercialized? Our research indicates that this is because much more efficient bladed turbines have been produced. However, those turbines are at least a factor of 10 times more expensive. '''''Thus, for particular applications, the boundary layer turbine may be a suitable, cost-effective option.''''' This is also the conclusion drawn on p. 35 of Rice, Warren, Transactions of the ASME, Journal of Engineering and Power, January 1965.