Solar Collector Calculations - Revision history

Jeremy at 18:16, 10 April 2009

2009-04-10T18:16:51Z

← Older revision		Revision as of 18:16, 10 April 2009
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	[[Category:Solar Turbine]]		[[Category:Solar Turbine]]

			[[Category:Solar Concentrator]]

2009-01-31T17:26:22Z

generating steam

← Older revision		Revision as of 17:26, 31 January 2009
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	'''Power''' = 20,000 J/s (20 Kw)		'''Power''' = 20,000 J/s (20 Kw)

	'''Change in temp''' = 300 C (from room temperature to 330 C)		'''Change in temp''' = 300 C (from room temperature to 330 C (603K) )

	'''specific heat'''= 4J/g		'''specific heat'''= 4J/g

2009-01-31T02:37:26Z

Theoretical maximum achievable temperature

← Older revision		Revision as of 02:37, 31 January 2009
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	For case 2, we can draw 18kW at room temperature. We can draw 15kW at 717K or 444C		For case 2, we can draw 18kW at room temperature. We can draw 15kW at 717K or 444C

	~~'''~~Absorber efficiency and operating temperature~~'''~~		=Absorber efficiency and operating temperature=

	This plot was made on Mathematica using the equation		This plot was made on Mathematica using the equation

2009-01-12T03:45:40Z

Summary: Available Power

← Older revision		Revision as of 03:45, 12 January 2009
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	#Flat black paint allows full solar absorption		#Flat black paint allows full solar absorption
	#Glass with selective coating addresses the blackbody radiation problem [http://www.newton.dep.anl.gov/askasci/phy00/phy00890.htm]		#Glass with selective coating addresses the blackbody radiation problem [http://www.newton.dep.anl.gov/askasci/phy00/phy00890.htm]


			[[Category:Solar Turbine]]

2008-07-11T16:03:47Z

Losses due to edge effects and lack of daily tracking

← Older revision		Revision as of 16:03, 11 July 2008
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	Someone please run this on the computer or analytically and fill in the exact value.		Someone please run this on the computer or analytically and fill in the exact value.

			=Losses Due to Air Mass=

			The lower that the sun is over the horizon, the larger the thickness of the atmosphere that the sun has to travel through. This reduces the solar income. Air mass calculator:

			http://www.udel.edu/igert/pvcdrom/SUNLIGHT/AIRMASS.HTM

	=Losses due to edge effects only=		=Losses due to edge effects only=

2008-07-07T20:55:59Z

Theoretical maximum achievable temperature

← Older revision		Revision as of 20:55, 7 July 2008
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	Efficency = Energy used/total energy in = (Input energy - energy losses)/Input energy		Efficency = Energy used/total energy in = (Input energy - energy losses)/Input energy

	where Input energy was 20000 times the optical efficency (1 for no coating, .9 for a coating)		where Input energy was 20000 times the optical efficency (1 for no coating, .9 for a coating)
	and e was 1, .4 and .1 for the different curves.		and e was 1, .4 and .1 for the different curves.

	Energy losses included radiative losses as well as conduction through the back insulation and		Energy losses included radiative losses as well as conduction through the back insulation and
	conduction out the aperature. Changing the R values for convective and conductive losses however		conduction out the aperature. Changing the R values for convective and conductive losses however

2008-07-07T20:55:33Z

Theoretical maximum achievable temperature

← Older revision		Revision as of 20:55, 7 July 2008
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	This plot was made on Mathematica using the equation		This plot was made on Mathematica using the equation

	Efficency = ~~Input - (1~~/20)11.3(t - ~~293) - 1.86(5.6710^-8)e(t^4 - 293^4)~~		Efficency = Energy used/total energy in = (Input energy - energy losses)/Input energy
	~~- .032(t - 293~~)/~~.5)/20000~~		where Input energy was 20000 times the optical efficency (1 for no coating, .9 for a coating)
	where Input was 20000 times the optical efficency (1 for no coating, .9 for a coating)
	and e was 1, .4 and .1 for the different curves.		and e was 1, .4 and .1 for the different curves.
			Energy losses included radiative losses as well as conduction through the back insulation and
	~~note:~~ Changing the R values for convective and conductive losses does not noticeably change the curves.		conduction out the aperature. Changing the R values for convective and conductive losses however
			does not noticeably change the curves.

	[[Image:absorbeff.jpg]]		[[Image:absorbeff.jpg]]

2008-07-07T20:50:57Z

Theoretical maximum achievable temperature

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	[[Image:systemeff.jpg]]		[[Image:systemeff.jpg]]

			By operating temperature it is meant the temperature of vaporization, which is roughly the average temperature of heat addition. this is the temperature that corresponds to the Carnot ideal, as opposed to the maximum temperature of superheated steam.

	note: The critical temperature for water is 647K.		note: The critical temperature for water is 647K.

2008-07-07T20:35:24Z

Theoretical maximum achievable temperature

← Older revision		Revision as of 20:35, 7 July 2008
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	(0 Celsius = 273 Kelvin)		(0 Celsius = 273 Kelvin)

	~~The~~ above curves were multiplied by the Carnot efficiency (assuming an exhaust temperature of 293K = 30C) to determine the total efficiency of the absorber and Rankine cycle. The operating temperature that gives the highest efficiency is the theoretical ideal operating point for the system.		'''Choosing the operating point'''

			Here, the above curves were multiplied by the Carnot efficiency (assuming an exhaust temperature of 293K = 30C) to determine the total efficiency of the absorber and Rankine cycle. The operating temperature that gives the highest efficiency is the theoretical ideal operating point for the system.

	note: the rankine efficency begins to deviate from the Carnot efficiency at higher temperatures (i don't know by how much), thus this graph is just slightly optimistic.		note: the rankine efficency begins to deviate from the Carnot efficiency at higher temperatures (i don't know by how much), thus this graph is just slightly optimistic.

2008-07-07T20:29:50Z

Theoretical maximum achievable temperature

← Older revision		Revision as of 20:29, 7 July 2008
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	'''Absorber efficiency and operating temperature'''		'''Absorber efficiency and operating temperature'''

	(~~does this case assume 0 conduction~~ and ~~0 convection from~~ the ~~collector, or all of non-radiated energy going into~~ the ~~collector? Source?)~~		This plot was made on Mathematica using the equation

			Efficency = Input - (1/20)11.3(t - 293) - 1.86(5.6710^-8)e(t^4 - 293^4)
			- .032(t - 293)/.5)/20000
			where Input was 20000 times the optical efficency (1 for no coating, .9 for a coating)
			and e was 1, .4 and .1 for the different curves.

			note: Changing the R values for convective and conductive losses does not noticeably change the curves.

	[[Image:absorbeff.jpg]]		[[Image:absorbeff.jpg]]

	(0 Celsius = 273 Kelvin)		(0 Celsius = 273 Kelvin)

			The above curves were multiplied by the Carnot efficiency (assuming an exhaust temperature of 293K = 30C) to determine the total efficiency of the absorber and Rankine cycle. The operating temperature that gives the highest efficiency is the theoretical ideal operating point for the system.

			note: the rankine efficency begins to deviate from the Carnot efficiency at higher temperatures (i don't know by how much), thus this graph is just slightly optimistic.

			[[Image:systemeff.jpg]]

			note: The critical temperature for water is 647K.

	=Summary: Available Power=		=Summary: Available Power=