2812: Solar Panel Placement - Revision history

Xurkitree10: /* Transcript */

2024-09-28T18:28:38Z

‎Transcript

Jkshapiro: /* Explanation */ Fix typo

2024-07-04T01:59:09Z

‎Explanation: Fix typo

1234231587678: 1m2 is confusing

2024-03-27T03:03:46Z

1m2 is confusing

Kynde: /* Explanation */

2024-01-18T12:18:16Z

‎Explanation

172.70.246.167: Expanded explanation slightly. Marked complete as last change was 1.5 months ago and explanation seems complete.

2023-10-05T07:46:21Z

Expanded explanation slightly. Marked complete as last change was 1.5 months ago and explanation seems complete.

172.71.158.75: /* Explanation */ spelling

2023-08-15T18:46:43Z

‎Explanation: spelling

172.71.158.74: /* Explanation */

2023-08-15T18:44:54Z

‎Explanation

172.71.82.38: /* Explanation */ Corrected the perhelion distance from the surface of the sun for the Parker Solar Probe from 6 kilometers (6000 meters, slightly less than 4 miles) to 6.2 million kilometers (slightly farther away, slightly less molten)

2023-08-14T20:25:13Z

‎Explanation: Corrected the perhelion distance from the surface of the sun for the Parker Solar Probe from 6 kilometers (6000 meters, slightly less than 4 miles) to 6.2 million kilometers (slightly farther away, slightly less molten)

Mtcv: paying for itself?

2023-08-14T13:47:11Z

paying for itself?

Tromag at 21:16, 10 August 2023

2023-08-10T21:16:14Z

← Older revision		Revision as of 18:28, 28 September 2024
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	==Transcript==		==Transcript==
−	~~{{incomplete transcript\|Do NOT delete this tag too soon.}}~~
−
	:[Heading:] Option A:		:[Heading:] Option A:

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 The strip then proposes a rather intense comparison: place the identical solar panel ''downwards'', on and towards the Sun, rather than ''upwards'' (upon a suitable equatorially-facing sloping roof), from the surface of the Earth. Due to the inverse-square law, this would result in ''much'' more solar energy striking the panel. If we assume that the solar cells could convert this energy to electricity at the same efficiency, then this would generate immense amounts of usable power, with the same calculation yielding $22 million per year as the value of a single panel in such a position.
-Of course, such setup would clearly be impossible, for the simple reason that the panels would melt and then vaporize long before they reached the surface of the sun. In point of fact, current photovoltaics operate less effectively at higher temperatures, so even bringing them mildly closer to the sun would impair their efficiency, and eventually cause them to stop working all together. This is in addition to the fact (acknowledged in the title text), that electricity produced at the sun's surface would be of little use to humans. The solution of "run[ning] transmission lines to earth" would obviously not be practical, even with millions of dollars at stake.
+Of course, such setup would clearly be impossible, for the simple reason that the panels would melt and then vaporize long before they reached the surface of the sun. In point of fact, current photovoltaics operate less effectively at higher temperatures, so even bringing them mildly closer to the sun would impair their efficiency, and eventually cause them to stop working altogether. This is in addition to the fact (acknowledged in the title text), that electricity produced at the sun's surface would be of little use to humans. The solution of "run[ning] transmission lines to earth" would obviously not be practical, even with millions of dollars at stake.
 The assertion that the solar panel would pay for itself in no time seems flawed. For example the Helios 1 probe cost 260 million dollars in 1975 (approximately 1.5 billion dollars in 2023 money) and the Parker Solar Probe, which will fly 6.2 million km from the surface of the sun, also cost 1.5 billion dollars. The Parker Solar probe mass is 50kg, which is the same order of magnitude as a 1m² solar panel.

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 Of course, such setup would clearly be impossible, for the simple reason that the panels would melt and then vaporize long before they reached the surface of the sun. In point of fact, current photovoltaics operate less effectively at higher temperatures, so even bringing them mildly closer to the sun would impair their efficiency, and eventually cause them to stop working all together. This is in addition to the fact (acknowledged in the title text), that electricity produced at the sun's surface would be of little use to humans. The solution of "run[ning] transmission lines to earth" would obviously not be practical, even with millions of dollars at stake.
-The assertion that the solar panel would pay for itself in no time seems flawed. For example the Helios 1 probe cost 260 million dollars in 1975 (approximately 1.5 billion dollars in 2023 money) and the Parker Solar Probe, which will fly 6.2 million km from the surface of the sun, also cost 1.5 billion dollars. The Parker Solar probe mass is 50kg, which is the same order of magnitude as a 1m2 solar panel.
+The assertion that the solar panel would pay for itself in no time seems flawed. For example the Helios 1 probe cost 260 million dollars in 1975 (approximately 1.5 billion dollars in 2023 money) and the Parker Solar Probe, which will fly 6.2 million km from the surface of the sun, also cost 1.5 billion dollars. The Parker Solar probe mass is 50kg, which is the same order of magnitude as a 1m² solar panel.
 There are conceptual proposals, for {{w|Space-based_solar_power|siting solar arrays in space}}, but in orbit around earth, rather than than on the sun. This would allow for somewhat more solar intensity, and provide more consistent power, but the obstacles of launching the arrays into space and then transmitting the power remain serious pragmatic difficulties.

← Older revision		Revision as of 12:18, 18 January 2024
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	==Explanation==		==Explanation==
		+	This is another one of [[Randall\|Randall's]] [[:Category:Tips\|Tips]], this time a solar energy tip.

	{{w\|Solar panels\|Solar panels}} generally produce electrical power in proportion to the intensity of sunlight striking them. In order to maximize energy production, it's generally recommended that panels be mounted at an angle that will receive the most light intensity, on average, and avoiding anything that might shade the panels. The comic might be poking fun at how sometimes solar panel arrays are installed in unusual orientations to ensure a south-facing orientation and pushing it to its logical extreme by assuming a panel on the sun.		{{w\|Solar panels\|Solar panels}} generally produce electrical power in proportion to the intensity of sunlight striking them. In order to maximize energy production, it's generally recommended that panels be mounted at an angle that will receive the most light intensity, on average, and avoiding anything that might shade the panels. The comic might be poking fun at how sometimes solar panel arrays are installed in unusual orientations to ensure a south-facing orientation and pushing it to its logical extreme by assuming a panel on the sun.

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 ==Explanation==
-{{w|Solar panels|Solar panels}} generally produce electrical power in proportion to the intensity of sunlight striking them. In order to maximize energy production, it's generally recommended that panels be mounted at an angle that will receive the most light intensity, on average, and avoiding anything that might shade the panels. Based on where the panel is located, the average amount of solar energy expected to strike it per day can be calculated (accounting for the angle of the sun, day and night cycles, and typical weather patterns). With this data, as well as the expected conversion efficiency and local cost of electricity, one can calculate the value of electricity the panel produces each year.
+{{w|Solar panels|Solar panels}} generally produce electrical power in proportion to the intensity of sunlight striking them. In order to maximize energy production, it's generally recommended that panels be mounted at an angle that will receive the most light intensity, on average, and avoiding anything that might shade the panels. The comic might be poking fun at how sometimes solar panel arrays are installed in unusual orientations to ensure a south-facing orientation and pushing it to its logical extreme by assuming a panel on the sun.
-In this case, [[Randall]] estimates the value of power produced by each square meter of solar cells at $58 per year.
+Based on where the panel is located, the average amount of solar energy expected to strike it per day can be calculated (accounting for the angle of the sun, day and night cycles, and typical weather patterns). With this data, as well as the expected conversion efficiency and local cost of electricity, one can calculate the value of electricity the panel produces each year. In this case, [[Randall]] estimates the value of power produced by each square meter of solar cells at $58 per year.
 The strip then proposes a rather intense comparison: place the identical solar panel ''downwards'', on and towards the Sun, rather than ''upwards'' (upon a suitable equatorially-facing sloping roof), from the surface of the Earth. Due to the inverse-square law, this would result in ''much'' more solar energy striking the panel. If we assume that the solar cells could convert this energy to electricity at the same efficiency, then this would generate immense amounts of usable power, with the same calculation yielding $22 million per year as the value of a single panel in such a position.

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 Solar panel area is measured in square meters.
-Solar panel efficiency, a dimensionless quantity, is the fraction of solar power that a panel can effectively convert into electricity. Here, both panels are assumed to be 20% efficient, which is a [https://www.forbes.com/home-improvement/solar/best-solar-panels/ reasonable estimate] for commercially available photovoltaic cells.
+Solar panel efficiency, a dimensionless quantity, is the fraction of solar power that a panel can effectively convert into electricity. Here, both panels are assumed to be 20% efficient, which is a [https://www.forbes.com/home-improvement/solar/best-solar-panels/ reasonable estimate] for commercially available photovoltaic cells operated near room temperature (300K).
 Multiplying these quantities together yields a unit of money per unit time, per area (dollars per day per square meter with these specific units). For the parameters for the Earth-bound example, the formula yields $0.16 per day in effective earnings, which can be multiplied by 365 to get approximately $58 per year. For the parameters on the Sun, it instead yields $60,400 per day in earnings, or approximately $22 million per year.

← Older revision		Revision as of 13:47, 14 August 2023
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	Of course, such setup would clearly be impossible, for the simple reason that the panels would melt and then vaporize long before they reached the surface of the sun. In point of fact, current photovoltaics operate less effectively at higher temperatures, so even bringing them mildly closer to the sun would impair their efficiency, and eventually cause them to stop working all together. This is in addition to the fact (acknowledged in the title text), that electricity produced at the sun's surface would be of little use to humans. The solution of "run[ning] transmission lines to earth" would obviously not be practical, even with millions of dollars at stake.		Of course, such setup would clearly be impossible, for the simple reason that the panels would melt and then vaporize long before they reached the surface of the sun. In point of fact, current photovoltaics operate less effectively at higher temperatures, so even bringing them mildly closer to the sun would impair their efficiency, and eventually cause them to stop working all together. This is in addition to the fact (acknowledged in the title text), that electricity produced at the sun's surface would be of little use to humans. The solution of "run[ning] transmission lines to earth" would obviously not be practical, even with millions of dollars at stake.
		+
		+	The assertion that the solar panel would pay for itself in no time seems flawed. For example the Helios 1 probe cost 260 million dollars in 1975 (approximately 1.5 billion dollars in 2023 money) and the Parker Solar Probe, which will fly 6km from the surface of the sun, also cost 1.5 billion dollars. The Parker Solar probe mass is 50kg, which is the same order of magnitude as a 1m2 solar panel.

	There are conceptual proposals, for {{w\|Space-based_solar_power\|siting solar arrays in space}}, but in orbit around earth, rather than than on the sun. This would allow for somewhat more solar intensity, and provide more consistent power, but the obstacles of launching the arrays into space and then transmitting the power remain serious pragmatic difficulties.		There are conceptual proposals, for {{w\|Space-based_solar_power\|siting solar arrays in space}}, but in orbit around earth, rather than than on the sun. This would allow for somewhat more solar intensity, and provide more consistent power, but the obstacles of launching the arrays into space and then transmitting the power remain serious pragmatic difficulties.

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 {{incomplete|Created by an underpaid solar panel installer - Please change this comment when editing this page. Do NOT delete this tag too soon.}}
-{{w|Solar panels|Solar panels}} are a relatively common method of supplying/augmenting power  for uses from calculators to factories. They work by gathering solar energy reaching the Earth from the Sun and converting it to electricity. More specifically, they absorb vast amounts of photons from the solar rays and use them to knock electrons free. Those electrons produce the flow of electric current around the circuit and convey power onwards to where it is needed.
+{{w|Solar panels|Solar panels}} generally produce electrical power in proportion to the intensity of sunlight striking them. In order to maximize energy production, it's generally recommended that panels be mounted at an angle that will receive the most light intensity, on average, and avoiding anything that might shade the panels. Based on where the panel is located, the average amount of solar energy expected to strike it per day can be calculated (accounting for the angle of the sun, day and night cycles, and typical weather patterns). With this data, as well as the expected conversion efficiency and local cost of electricity, one can calculate the value of electricity the panel produces each year.
-This comic proposes a solution to the issue of solar panels not generating enough power due to basic physical limitations. Solar panels on Earth have multiple things reducing their efficacy, such as their distance from the Sun as well as atmospheric effects reducing the intensity of light hitting them and the fact that for half of the time they can't generate any power because their position on the Earth is facing away from the Sun. Putting your solar panels in a close orbit above the Sun would eliminate most, if not all, of these issues (and is a partial implementation of the concept of a {{w|Dyson sphere}}, theorised by scientists and used in science fiction). However putting solar panels on the surface of the Sun, as suggested here, introduces many new problems that can negatively impact their energy generating capacity, such as transmission losses, reduced conversion efficiency due to high temperatures and more undesirable effects from their proximity to the Sun, including total destruction of the panels.
+In this case, [[Randall]] estimates the value of power produced by each square meter of solar cells at $58 per year.
-The cost-effectiveness of solar panels is a complex topic, involving [https://www.energy.gov/eere/solar/solar-performance-and-efficiency efficiency], installation, and even costs of [https://cen.acs.org/environment/recycling/Solar-panels-face-recycling-challenge-photovoltaic-waste/100/i18 recycling at end-of-life]. The comic demonstrates a simplified calculation, where a solar panel of 1m<sup>2</sup> is estimated to return electricity equivalent to around $58/year, using 20% as the efficiency of conversion of sunlight to electricity for an otherwise optimally roof-installed solar panel unit.
+The strip then proposes a rather intense comparison: place the identical solar panel ''downwards'', on and towards the Sun, rather than ''upwards'' (upon a suitable equitorially-facing sloping roof), from the surface of the Earth. Due to the inverse-square law, this would result in ''much'' more solar energy striking the panel. If we assume that the solar cells could convert this energy to electricity at the same efficiency, then this would generate immense amounts of usable power, with the same calculation yielding $22 million per year as the value of a single panel in such a position.
-To solve this, Randall here proposes a rather more direct solution: place the identical solar panel ''downwards'', on and towards the Sun, rather than ''upwards'' (upon a suitable equitorially-facing sloping roof), from the surface of the Earth. This gives access to substantially more light energy and would (through naïve upscaling of the power flux available, ignoring a number of technical issues) produce greatly increased amounts of energy for the owner.
+Of course, such setup would clearly be impossible, for the simple reason that the panels would melt and then vaporize long before they reached the surface of the sun. In point of fact, current photovoltaics operate less effectively at higher temperatures, so even bringing them mildly closer to the sun would impair their efficiency, and eventually cause them to stop working all together. This is in addition to the fact (acknowledged in the title text), that electricity produced at the sun's surface would be of little use to humans. The solution of "run[ning] transmission lines to earth" would obviously not be practical, even with millions of dollars at stake.
-The title text acknowledges ''some'' difficulties, but hand-waves them away as being surmountable and entirely worthwhile given the theoretical income generated. This may or may not be true, but is actually extremely unlikely at the end of the economies of scale whereby an individual is expected to make their own best use of a single solar panel. Perhaps in this case a better interpretation of "in no time" is "never".
+There are conceptual proposals, for {{w|Space-based_solar_power|siting solar arrays in space}}, but in orbit around earth, rather than than on the sun. This would allow for somewhat more solar intensity, and provide more consistent power, but the obstacles of launching the arrays into space and then transmitting the power remain serious pragmatic difficulties.
 ;Calculations
 The formula Randall uses in this comic is electricity price × solar irradiance × panel area × panel efficiency = savings.
-Electricity price is measured in dollars per kilowatt-hour, a unit commonly used by electric utility companies. In both cases, it is assumed to be $0.20 per kilowatt-hour, which is a [https://www.eia.gov/electricity/monthly/epm_table_grapher.php?t=epmt_5_6_a reasonable estimate].
+Electricity price is measured in dollars per kilowatt-hour, a unit commonly used by electric utility companies. In both cases, it is assumed to be $0.20 per kilowatt-hour, which is a [https://www.eia.gov/electricity/monthly/epm_table_grapher.php?t=epmt_5_6_a reasonable estimate] for domestic, retail electric rates in [[Randall]]'s home of Massachusetts.
-{{w|Solar irradiance}}, a special case of {{w|irradiance}}, is the total amount of power delivered to a surface by the Sun per unit area. Here, it is measured in kilowatt-hours per square meter per day, although watts per square meter is the SI unit. Randall assumes it to be 4 kWh/m<sup>2</sup>/day on Earth. He also calculates it for the surface of the Sun as its total luminosity (electromagnetic power, ≈3.83×10<sup>26</sup> W) divided by its total area (≈6.07×10<sup>18</sup> m<sup>2</sup>), which comes out to around 6.31×10<sup>7</sup> W/m<sup>2</sup> or 1.51×10<sup>6</sup> kWh/m<sup>2</sup>/day.
+Solar panel efficiency, a dimensionless quantity, is the fraction of solar power that a panel can effectively convert into electricity. Here, both panels are assumed to be 20% efficient, which is a [https://www.forbes.com/home-improvement/solar/best-solar-panels/ reasonable estimate] for commercially available photovoltaic cells.
-Solar panel area is measured in square meters. Here, the panel in both cases is assumed to be 1 square meter in area.
+Multiplying these quantities together yields a unit of money per unit time, per area (dollars per day per square meter with these specific units). For the parameters for the Earth-bound example, the formula yields $0.16 per day in effective earnings, which can be multiplied by 365 to get approximately $58 per year. For the parameters on the Sun, it instead yields $60,400 per day in earnings, or approximately $22 million per year.
-Solar panel efficiency, a dimensionless quantity, is the fraction of solar power that a panel can effectively convert into electricity. Here, both panels are assumed to be 20% efficient, which is a [https://www.forbes.com/home-improvement/solar/best-solar-panels/ reasonable estimate] as well.
+It should be noted that these values are for each square meter of solar panel. Solar systems almost always consist of multiple panels. With the same assumptions, a 30-square-meter system (which is a relatively small, home system) would be worth $1,740 per year.
 ==Transcript==