Archive:000/Photovoltaics - Revision history

Elie: Elie moved page Photovoltaics to Archive:000/Photovoltaics without leaving a redirect: Huge_refactor

2024-10-26T20:30:06Z

Elie moved page Photovoltaics to Archive:000/Photovoltaics without leaving a redirect: Huge_refactor

← Older revision	Revision as of 16:30, 26 October 2024
(No difference)

Elie: /* Land usage */

2023-11-03T19:50:52Z

Land usage

← Older revision		Revision as of 15:50, 3 November 2023
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	In general, rooftop solar can almost always provide enough ''electricity'' for a house (and even charge an [[EV]] in many cases), but not always enough [[heating]].		In general, rooftop solar can almost always provide enough ''electricity'' for a house (and even charge an [[EV]] in many cases), but not always enough [[heating]].

	{{minor\|For heating~~, burning~~ [[hydrogen gas]] (generated from [[wind]] power) could probably make up the difference.}}		{{minor\|For heating: Burning [[hydrogen gas]] (generated from [[wind]] power) could probably make up the difference.}}

Elie: /* Land usage */

2023-11-03T19:50:11Z

Land usage

← Older revision		Revision as of 15:50, 3 November 2023
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	In general, rooftop solar can almost always provide enough ''electricity'' for a house (and even charge an [[EV]] in many cases), but not always enough [[heating]].		In general, rooftop solar can almost always provide enough ''electricity'' for a house (and even charge an [[EV]] in many cases), but not always enough [[heating]].

	{{minor\|~~Burning~~ [[hydrogen gas]] (generated from [[wind]] power) could probably make up the difference.}}		{{minor\|For heating, burning [[hydrogen gas]] (generated from [[wind]] power) could probably make up the difference.}}


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	Compared to [[wind power]], solar is far less land-intensive {{x\|about 50x less, based on the fact that the atmosphere converts about 2% of the sun's energy (that hits the Earth) into winds}} but far more invasive to the land it ''does'' use. So [[rooftop solar]] should come first, as much as possible.		Compared to [[wind power]], solar is far less land-intensive {{x\|about 50x less, based on the fact that the atmosphere converts about 2% of the sun's energy (that hits the Earth) into winds}} but far more invasive to the land it ''does'' use. So [[rooftop solar]] should come first, as much as possible.


	==See also==		==See also==

Elie at 19:48, 3 November 2023

2023-11-03T19:48:01Z

← Older revision		Revision as of 15:48, 3 November 2023
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	In general, [[rooftop solar]] can almost always provide enough ''electricity'' for a house (and even charge an [[EV]] in many cases), but not always enough [[heating]].		In general, rooftop solar can almost always provide enough ''electricity'' for a house (and even charge an [[EV]] in many cases), but not always enough [[heating]].

	{{minor\|Burning [[hydrogen gas]] (generated from [[wind]] power) could probably make up the difference.}}		{{minor\|Burning [[hydrogen gas]] (generated from [[wind]] power) could probably make up the difference.}}
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	Compared to [[wind power]], solar is far less land-intensive {{x\|about 50x less, based on the fact that the atmosphere converts about 2% of the sun's energy (that hits the Earth) into winds}} but far more invasive to the land it ''does'' use.		Compared to [[wind power]], solar is far less land-intensive {{x\|about 50x less, based on the fact that the atmosphere converts about 2% of the sun's energy (that hits the Earth) into winds}} but far more invasive to the land it ''does'' use. So [[rooftop solar]] should come first, as much as possible.


	==See also==		==See also==
	* [[Solar thermal panels]] - {{light\|Not electric~~, only~~ for heating water & air.<!--[[hot water\|water]] and [[heating\|air]].-->}}		* [[Solar thermal panels]] - {{light\|Not electric. Only for heating water & air.<!--[[hot water\|water]] and [[heating\|air]].-->}}
	* [[Concentrated solar thermal]]		* [[Concentrated solar thermal]]
	* [[Concentrator photovoltaics]]		* [[Concentrator photovoltaics]]

Elie at 19:42, 3 November 2023

2023-11-03T19:42:53Z

← Older revision		Revision as of 15:42, 3 November 2023
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	Photovoltaics (PV) are any '''solar panels''' that produce electricity.		Photovoltaics (PV) are any '''solar panels''' that produce electricity.
			<!-- I bolded "solar panels" instead of "photovoltaics", because plenty of new readers have never heard the word "photovoltaics" before. [[Solar panels]] redirects here. -->
	<!--: {{minor\|''Not to be confused with [[solar thermal panels]] (non-electric) which just heat air or water in the sun.''}}-->		<!--: {{minor\|''Not to be confused with [[solar thermal panels]] (non-electric) which just heat air or water in the sun.''}}-->

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	*** [[sodium-sulfur batteries]]		*** [[sodium-sulfur batteries]]
	*** [[sodium-ion batteries]]		*** [[sodium-ion batteries]]
	*** {{light\|~~The above~~ battery types are not on the market yet. Innovations are needed.}}		*** {{light\|These battery types (above) are not on the market yet. Innovations are needed.}}
	* ''Some'' excess summer daytime energy may be worth storing by producing [[hydrogen gas]] (which could be burned in the winter for [[heating]]).		* ''Some'' excess summer daytime energy may be worth storing by producing [[hydrogen gas]] (which could be burned in the winter for [[heating]]).
	* To reduce the need for energy storage, it would help if people were to charge their [[electric vehicles]] mostly during the day, and if factories were to run only during the day (and maybe even temporarily shut down in the winter). <sup>[new economics needed]</sup>		* To reduce the need for energy storage, it would help if people were to charge their [[electric vehicles]] mostly during the day, and if factories were to run only during the day (and maybe even temporarily shut down in the winter). <sup>[new economics needed]</sup>

Elie at 19:35, 3 November 2023

2023-11-03T19:35:06Z

← Older revision		Revision as of 15:35, 3 November 2023
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	Photovoltaics (PV) are any '''solar panels''' that produce electricity.		Photovoltaics (PV) are any '''solar panels''' that produce electricity.
			<!--: {{minor\|''Not to be confused with [[solar thermal panels]] (non-electric) which just heat air or water in the sun.''}}-->
	<~~small>~~Not to be confused with [[solar thermal panels]] (non-electric) which just heat air or water in the sun.~~</small~~>

	====Status quo====		====Status quo====
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	{{considerations}} __NOTOC__		{{considerations}} __NOTOC__


			==Scarce metals==
			{{sum\|Major problem}}

			''Thin-film photovoltaics'' are the most common types of solar panels used today. They are relatively efficient, but '''depend heavily''' on scarce minerals. There's simply no way they could be scaled up enough to replace fossil fuels. <br />{{more\|Solar panel minerals}}

			'''Solution:''' Find some other photovoltaic tech based on more abundant minerals. Sacrificing some efficiency is okay, for the sake of making cheaper, more scalable solar panels. <br />{{more\|solar/challenge 1}}


			==Recycling==
			{{sum\|Possible problem}}
			Status quo: Most solar panels are not recycled. Existing recycling plants can't recover very much of the rare metals in the panels. {{en}}

			As mentioned in the section above, we'll need to use some alternative solar panel tech anyway (one that is less dependent on scarce minerals). Whichever tech we choose, there will still be ''some'' metals involved, so it's more important than ever to make sure it can be recycled in a way that recovers those metals.


	==Intermittency==		==Intermittency==
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	''So if solar were to be '''scaled up enough''' to phase out fossil fuels,''		''So if solar were to be '''scaled up enough''' to phase out fossil fuels,''
	* We'd need ''at least'' enough battery [[energy storage]] to cover a full 24-hour cycle - or maybe a bit more.		* We'd need ''at least'' enough '''battery''' [[energy storage]] to cover a full 24-hour cycle - or maybe a bit more.
			** Energy storage is an [[The great battery challenge\|ongoing challenge]]. Best candidates for solar batteries might be...
			*** [[iron-redox flow batteries]]
			*** [[sodium-sulfur batteries]]
			*** [[sodium-ion batteries]]
			*** {{light\|The above battery types are not on the market yet. Innovations are needed.}}
	* ''Some'' excess summer daytime energy may be worth storing by producing [[hydrogen gas]] (which could be burned in the winter for [[heating]]).		* ''Some'' excess summer daytime energy may be worth storing by producing [[hydrogen gas]] (which could be burned in the winter for [[heating]]).
	* Energy storage is an [[The great battery challenge\|ongoing challenge]]. Best candidates for solar batteries might be [[iron-redox flow batteries]] or [[sodium-sulfur batteries]].		* To reduce the need for energy storage, it would help if people were to charge their [[electric vehicles]] mostly during the day, and if factories were to run only during the day (and maybe even temporarily shut down in the winter). <sup>[new economics needed]</sup>
	* To reduce the need for energy storage, it would help if people were to charge their [[electric vehicles]] mostly during the day, and if factories were to run only during the day (and maybe even temporarily shut down in the winter).

			==Energy in production==
			{{sum\|Fair / needs improvement}}

			[[Energy return on investment]]: about 7.5.

	~~==Scarce metals==~~		Solar panels are estimated to have an "energy payback" of about 4 years.{{cn}} In other words, for all the [[energy]] it takes to manufacture a solar panel, the solar panel will generate the same amount of energy after about 4 years of being installed. Since a solar panel is expected to last about 30 years, this comes out to an [[EROI]] ratio of 7.5.
	{{~~sum\|Major problem~~}}

	~~''Thin-film photovoltaics'' are the most common types of solar panels used today. They are relatively efficient~~, ~~but '''depend heavily''' on scarce minerals. There's simply no way they could be scaled up enough~~ to ~~replace~~ fossil fuels. ~~<br~~ /~~>{{~~more~~\|Solar panel minerals}}~~		4 years is a long time, which means that switching to solar might need a lot of fossil fuels to "get the ball rolling". A shorter energy payback time is a worthwhile goal, mentioned in: [[solar/challenge 1]]. This becomes even more important if there turns out to be a lot of energy losses in [[energy storage]].

	'''Solution:''' Find some other photovoltaic tech based on more abundant minerals. Sacrificing some efficiency is okay, for the sake of making cheaper, more scalable solar panels. <br />{{more\|solar/challenge 1}}

	==Land usage==		==Land usage==
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	<!--		<!--

	-->		---------------- -->
	In the simplest average case, [[solar rooftops]] are all that would be needed.		In the simplest average case, [[solar rooftops]] are all that would be needed.

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	Compared to [[wind power]], solar is far less land-intensive {{x\|about 50x less, based on the fact that the atmosphere converts about 2% of the sun's energy (that hits the Earth) into winds}} but far more invasive to the land it ''does'' use.		Compared to [[wind power]], solar is far less land-intensive {{x\|about 50x less, based on the fact that the atmosphere converts about 2% of the sun's energy (that hits the Earth) into winds}} but far more invasive to the land it ''does'' use.

	~~==Energy in production==~~
	~~{{sum\|Fair / maybe needs improvement}}~~

	~~[[Energy return on investment]]: about 7.5.~~

	Solar panels are estimated to have an "energy payback" of about 4 years.{{cn}} In other words, for all the [[energy]] it takes to manufacture a solar panel, the solar panel will generate the same amount of energy after about 4 years of being installed. Since a solar panel is expected to last about 30 years, this comes out to an [[EROI]] ratio of 7.5.

	4 years is a long time, which means that switching to solar might need a lot of fossil fuels to "get the ball rolling". A shorter energy payback time is a worthwhile goal, mentioned in: [[solar/challenge 1]].

	==See also==		==See also==
	* [[Solar thermal panels]]		* [[Solar thermal panels]] - {{light\|Not electric, only for heating water & air.<!--[[hot water\|water]] and [[heating\|air]].-->}}
	* [[Concentrated solar thermal]]		* [[Concentrated solar thermal]]
	* [[Concentrator photovoltaics]]		* [[Concentrator photovoltaics]]
	* [[Energy]]		* [[Energy]]


	<!-- TODO:		<!-- TODO:

Elie: /* See also */

2023-11-03T19:16:12Z

Elie: /* Rare metals */ Renamed to "scarce" to avoid confusion with rare-earth metals

2023-11-03T19:13:20Z

Rare metals: Renamed to "scarce" to avoid confusion with rare-earth metals

← Older revision		Revision as of 15:13, 3 November 2023
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	* To reduce the need for energy storage, it would help if people were to charge their [[electric vehicles]] mostly during the day, and if factories were to run only during the day (and maybe even temporarily shut down in the winter).		* To reduce the need for energy storage, it would help if people were to charge their [[electric vehicles]] mostly during the day, and if factories were to run only during the day (and maybe even temporarily shut down in the winter).

	==~~Rare~~ metals==		==Scarce metals==
	{{sum\|Major problem}}		{{sum\|Major problem}}

	''Thin-film photovoltaics'' are the most common types of solar panels used today. They are relatively efficient, but '''depend heavily''' on ~~rare~~ minerals. There's simply no way they could be scaled up enough to replace fossil fuels. <br />{{more\|Solar panel minerals}}		''Thin-film photovoltaics'' are the most common types of solar panels used today. They are relatively efficient, but '''depend heavily''' on scarce minerals. There's simply no way they could be scaled up enough to replace fossil fuels. <br />{{more\|Solar panel minerals}}

	'''Solution:''' Find some other photovoltaic tech based on more abundant minerals. Sacrificing some efficiency is okay, for the sake of making cheaper, more scalable solar panels. <br />{{more\|solar/challenge 1}}		'''Solution:''' Find some other photovoltaic tech based on more abundant minerals. Sacrificing some efficiency is okay, for the sake of making cheaper, more scalable solar panels. <br />{{more\|solar/challenge 1}}

Elie: /* Need for land */

2023-11-03T19:09:56Z

Need for land

@@ Line 34: / Line 34: @@
 '''Solution:''' Find some other photovoltaic tech based on more abundant minerals. Sacrificing some efficiency is okay, for the sake of making cheaper, more scalable solar panels. <br />{{more|solar/challenge 1}}
-==Need for land==
+==Land usage==
-{{sum|Usually ''not'' a problem}}
+{{sum|Reasonable}}
-[[Solar rooftops]] have enough surface area to power most of the world. Very dense cities are an exception, if they aren't surrounded by enough suburbs. Houses, if the rooftop is fully covered in solar panels, can generally produce ''surplus'' power which could power inner cities. <br />{{more|Rooftop solar}}
+-->
-[[Solar farms]] would be needed in cases where solar rooftops aren't enough. Some amount of [[land]] would be needed{{qn}}, but far less than what is used for agriculture. Solar panels should best be placed in areas with no fertile soil. They don't play well with agriculture, because (unlike [[wind]] power) solar panels block the sun that plants need to grow. Sure there are some crops that like the shade, but they could have just as well been grown in the shade of full-sun crops. See: [[polyculture]].
+<center><tab name="quick maths">
 ==Energy in production==

Elie at 20:29, 2 September 2023

2023-09-02T20:29:58Z

← Older revision		Revision as of 16:29, 2 September 2023
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	[[Category:Energy sources]]		[[Category:Energy sources]]

	Photovoltaics are any '''solar panels''' that produce electricity.		Photovoltaics (PV) are any '''solar panels''' that produce electricity.

	<small>Not to be confused with [[solar thermal panels]] (non-electric) which just heat air or water in the sun.</small>		<small>Not to be confused with [[solar thermal panels]] (non-electric) which just heat air or water in the sun.</small>
	<!--
	''~~If done right,~~'' ~~this could be a main~~ [[~~energy~~]] ~~source for the world~~.		====Status quo====
	~~-->~~		As of 2023, solar provides about 1% of the world's [[energy]]
			<!-- TODO: add calculation using {{dp\|energy.tfc\|...}} and datapoints from https://www.iea.org/energy-system/renewables/solar-pv (1300 TWh/year) -->
			(5% of ''electricity''). If we want to phase out [[fossil fuels]], then solar might need to scale up by over 50x. This comes with challenges.

	{{considerations}} __NOTOC__		{{considerations}} __NOTOC__

	==Intermittency==		==Intermittency==
	{{sum\|Needs [[energy storage]]}}		{{sum\|Needs [[energy storage]]}}

	~~The sun~~ only ~~shines~~ during the day. ~~Solar electricity~~{{~~x\|if used as a main energy source~~}}~~would need ''at least'' enough [[energy storage]] to cover a full 24-hour cycle - or maybe a bit more.~~		'''Short-term fluctuation:''' Solar panels only produce electricity during the day, not at night. Cloudy & overcast days still produce a generous amount of power, although slightly less. Days with heavy rain produce less.{{qn}}

	~~Cloudy & overcast days still~~ produce ~~a generous amount of power, although slightly~~ less. ~~Heavy rain can be an exception.~~		'''Long-term fluctuation:''' Solar panels produce less energy in the winter than in the summer.{{qn\| / case studies}}

	Energy storage is an [[The great battery challenge\|ongoing challenge]]. Best candidates for solar might be [[iron-redox flow batteries]] or [[sodium-sulfur batteries]].
			''So if solar were to be '''scaled up enough''' to phase out fossil fuels,''
			* We'd need ''at least'' enough battery [[energy storage]] to cover a full 24-hour cycle - or maybe a bit more.
			* ''Some'' excess summer daytime energy may be worth storing by producing [[hydrogen gas]] (which could be burned in the winter for [[heating]]).
			* Energy storage is an [[The great battery challenge\|ongoing challenge]]. Best candidates for solar batteries might be [[iron-redox flow batteries]] or [[sodium-sulfur batteries]].
			* To reduce the need for energy storage, it would help if people were to charge their [[electric vehicles]] mostly during the day, and if factories were to run only during the day (and maybe even temporarily shut down in the winter).

	==Rare metals==		==Rare metals==
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	==See also==		==See also==
	* [[Concentrator photovoltaics]]		<!-- * [[Concentrator photovoltaics]] TALK: maybe remove this since it's not all that viable? -->
			* [[Wind]]
	* [[Energy]]		* [[Energy]]

			<!-- TODO:
			==Maintenance== - solar panels need to be kept clean?
			==Safety== - anything worth knowing?
			-->

← Older revision		Revision as of 15:16, 3 November 2023
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	==See also==		==See also==
	~~<!--~~ * [[~~Concentrator photovoltaics~~]] ~~TALK: maybe remove this since it's not all that viable? -->~~		* [[Solar thermal panels]]
	* [[~~Wind~~]]		* [[Concentrated solar thermal]]
			* [[Concentrator photovoltaics]]
	* [[Energy]]		* [[Energy]]