Socio-Scientific Issues
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Day 1
Introduction
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JUDGE
DEFENDANT
DEFENDANT
ATTORNEY
PLAINTIFF
PLAINTIFF
ATTORNEY
U
R
Y
J
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LAW: Solar Shade Control Act (AB 2321): "No person...shall allow a tree...to grow...after the installation of a solar (panels)...on the property of another so as to cast a shadow greater than 10 percent“ during the day.
The DEFENDANT planted redwood trees in their backyard before their neighbor installed solar panels and refuses to cut them down.
The PLAINTIFF believes the trees in the defendant’s yard violate the Solar Shade Control Act and should be removed.
ARE THE TREES GUILTY OF CAUSING A LOSS OF MORE THAN 10% of SOLAR OUTPUT?
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LAW: Solar Shade Control Act (AB 2321): "No person...shall allow a tree...to grow...after the installation of a solar (panels)...on the property of another so as to cast a shadow greater than 10 percent“ during the day.
The DEFENDANT planted redwood trees in their backyard before their neighbor installed solar panels and refuses to cut them down.
The PLAINTIFF believes the trees in the defendant’s yard violate the Solar Shade Control Act and should be removed.
ARE THE TREES GUILTY OF CAUSING A LOSS OF MORE THAN 10% of SOLAR OUTPUT?
Getting to Know Solar
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What everyday objects are powered by solar cells?
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How do solar panels produce electricity using solar energy?
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Day 2
Solar Science Concepts
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Sun Angles
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Sun Angles in Aladdin
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The Sun moves across the sky from sunrise to sunset. The Sun’s path refers to its trajectory that an observer on the Earth perceives. The direction of the Sun relative to a horizontal surface on the Earth at a given time dictates how much solar energy it receives at that moment (which partly drives the temperature variations throughout a day). The direction can be represented by three angles: zenith angle, elevation angle, and azimuth angle. The zenith angle is the angle between sunlight and the vertical direction. The elevation angle is the angle between sunlight and the horizontal direction (complementary to the zenith angle). And the azimuth angle is the angle between sunlight and the north direction. These angles change all the time as the Sun moves along its path in a day.
To observe these changes, open Tutorials > Solar Science Basics > Sun Path in Aladdin and follow the instruction in Sheet 1.
Solargraphy captures the Sun’s path across the sky throughout the year of 2014 in Budapest. Credit: Elekes Andor
The Sun’s Path (cont.)
A. Daily Change of Solar Angles
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The seasonal change on the Earth occurs due to the tilt of its axis of rotation relative to the ecliptic—the plane of its orbit around the Sun.1 There are four special points on the Earth’s orbit around the Sun, which correspond to four special days of the year—the equinoxes and solstices.
1 The seasons are not caused by the Earth’s proximity to the Sun. In fact, the Earth is slightly closer to the Sun in the winter than it is in the summer for the northern hemisphere.
B. Seasonal Change of Solar Angles
To observe the seasonal changes of the Sun’s direction, open Tutorials > Solar Science Basics > Sun Path in Aladdin and follow the instruction in Sheet 2.
Solstices and equinoxes. Credit: National Weather Service
The Sun’s Path (cont.)
Day 3
Solar Science Concepts II
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The total solar energy that strikes a surface on the Earth in a given day depends on the length of the day—the lapse of time from sunrise to sunset known as daytime. As the Sun’s path changes from season to season, the daytime varies throughout the year.
C. Seasonal Changes of Daytime
To observe the seasonal changes of daytime, open Tutorials > Solar Science Basics > Sun Path in Aladdin and follow the instruction in Sheet 3.
The daytime varies from season to season as the Sun’s path changes (northern hemisphere).
The Sun’s Path (cont.)
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As the Earth spins, different parts of the world may receive different amounts of solar energy on the same day. During the March and September equinoxes. the Sun is directly overhead at the Equator and the daytime is the same everywhere on the Earth (the lengths of day and night are also the same—12 hours each). But during the June solstice, the Sun is above the Tropic of Cancer (23.5° north to the Equator). It never sets at the North Pole and never rises at the South Pole. On the other hand, during the December solstice, the Sun is above the Tropic of Capricorn (23.5° south to the Equator). It never rises at the North Pole and never sets at the South Pole.
D. The Sun’s Path in Different Parts of the World
To observe the Sun’s path in different parts of the world, open Tutorials > Solar Science Basics > Sun Path in Aladdin and follow the instruction in Sheet 4.
The Sun’s direction relative to the Equator, the Tropic of Cancer, and the Tropic of Capricorn in different seasons . Credit: Merriam-Webster, Inc.
The Sun’s Path (cont.)
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Now you have an opportunity to apply what you have learned to solve a real-world problem as follows.
Judd just bought a solar panel. Now he has to figure out where to install it around his house and how to orient it so that it can generate the most electricity.
To help him make decision, open Optimize It! in Aladdin to work on a 3D model of his house and the solar panel. Follow the instruction in Sheet 1 to search for a “sweet spot” for the solar panel.
Find a position for a solar panel around a house that generates most electricity throughout a year.
Test Your Knowledge
Day 4
Role Assignment &
Evidence Collection
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DEFENDANT
DEFENDANT
ATTORNEY
Will present their evidence of why their trees are not guilty.
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PLAINTIFF
PLAINTIFF
ATTORNEY
Will present their evidence of why the trees are guilty and should be removed.
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U
R
Y
J
Will present their reasoning of why they find the defendant guilty or not guilty.
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JUDGE
Will listen to the jury’s decision and make the final ruling on what the defendant must do based on the jury’s verdict.
Day 5
Reasoning Skill Coach
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Day 6
Evidence Collection II
Writing Opening Statement
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Day 7
Trial
Presenting Opening Statement
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Day 8
Writing Final Argument
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Day 9
Final Argument & Verdict
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Day 10
Closing Activities
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THE REVEAL
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The judge found that Trees Nos. 1, 2, and 3, which cast little shade when the solar panels were installed, were now collectively blocking more than 10 percent of the panels.
As a result of this case, State Senator Joe Simitian introduced Senate Bill 1399 as an amendment to the Solar Shade Control Act to exempt all trees and shrubs planted prior to the installation of a solar panel. The bill was signed into law by Governor Arnold Schwarzenegger in 2008.