Difference between revisions of "Sustainable Energy Vehicle Competition"

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= Objective =
= Objective =


The objective of this lab is to understand the applications and future trends of renewable energy. To do so, the first experimental objective is to investigate and evaluate solar power and wind power as sources of renewable energy and use the results of that evaluation to power a sustainable energy vehicle. The second experimental objective is to graphically compile and analyze the monthly energy consumption data from various renewable energy sources to understand the historical rising trend of renewable energy usage.
The objective of this lab is to evaluate different sources of renewable energy and use the results of that evaluation to design a vehicle that is either directly powered by a renewable energy source or a capacitor that is charged by a renewable energy source. The design will be entered in a competition that is judged by an equation that includes the distance traveled, travel time, and cost.


= Overview =
= Overview =


While humans have been using renewable energy sources, such as sails to power boats, windmills to pump water, or water-driven wheels to power machinery that mills grains, for millennia, the environmental impact of burning fossil fuels, such as oil, natural gas, and coal, has prompted greater interest in and greater investment in renewable energy sources, including solar power, wind power, and hydroelectric power. But some renewable energy sources cannot generate power consistently, notably solar power and wind power, so there is equal interest in developing energy storage devices that can operate at grid-scale or hold sufficient energy to power entire communities for an extended time after being charged by a renewable energy source.
From sails to power boats, windmills to pump water, or water-driven wheels to power machinery that mills grains, humans have been using renewable energy sources for millennia. A significant amount of our energy production comes from non-renewable resources, such as oil, natural gas, and coal. The detrimental effects on public health and the environment from burning fossil fuels have prompted greater interest and investment in renewable energy sources, including solar, wind, and hydroelectric power though hydroelectric power is not considered in this lab. Scientists and engineers must address concerns about the inability of some renewable sources, notably solar power and wind power, to generate power consistently so there is equal interest in developing energy storage devices that can operate at grid-scale or hold sufficient energy to power entire communities for an extended time after being charged by a renewable energy source.


== Types of Renewable Energy ==
== Types of Renewable Energy ==


<b>Renewable energy</b> is a type of energy that can be harnessed from naturally replenished resources. Some examples of this are sunlight, wind, and water. There are many benefits of using renewable energy. They are clean energy sources, and they come from an abundant source that do not become depleted. If these renewable resources can be harnessed efficiently, they can solve the problems with using non-renewable energy sources, such as fossil fuels (NextEra Energy Resources, 2012).
<b>Renewable energy</b> is a type of energy that can be harnessed from naturally replenished resources. Some examples of renewable energy sources are sunlight, wind, and water. There are many benefits to using renewable energy. If these renewable resources can be harnessed effectively, they can solve the problems with using non-renewable energy sources (NextEra Energy Resources, 2012). In the last few years, renewable energy has been the fastest-growing energy source globally (International Energy Agency, 2021). In this lab, solar and wind energy will be used.  


=== Solar Power ===
=== Solar Power ===


Sunlight, like any other type of electromagnetic radiation, contains energy. Typically, when sunlight hits an object, the energy that it contains is converted into heat. Certain materials can convert the energy into an electrical current. In this form, it can be used as a power source and it can be stored as energy.
Sunlight, like any other type of electromagnetic radiation, contains energy. Typically, when sunlight hits an object, the energy that it contains is converted into heat. Certain materials can absorb and convert that energy into an electrical current. In this form, sunlight can be used as a power source or stored for later use.


In a crystal structure, the materials used for <b>solar panels</b> contain covalent bonds where electrons are shared by the atoms within the crystal. When the light is absorbed, electrons within the crystal become excited and move to a higher energy level. When this occurs, the electron has more freedom of movement within the crystal. When the electrons move around the crystal structure an electrical current is generated. The reaction that occurs when sunlight hits a solar panel is shown in Figure 1 (Locke, 2008).
<b>Solar panels</b> are semiconductor-based devices that generate electrical current directly from sunlight. Many high-efficiency solar panels comercially available are made from crystalline silicon (Si).  


[[Image:Lab_renewener_01.png|thumb|500px|center|Figure 1: A Silicon Solar Panel Showing the Electron Flow]]
To produce a current, there must be a difference in the concentration of electrons between one area and another to cause their flow. In a silicon solar cell, a concentration difference is created using two types of silicon, <b>p-type</b> and <b>n-type</b>. The p-type silicon is created by adding atoms, such as boron, that have one fewer electron in their valence energy level than silicon has. As a result, a vacancy of electrons, or a hole, forms. The n-type silicon is created by adding atoms that have one more electron in their valence energy level than silicon has so that there is an excess of electrons that can move around the crystal structure and create an electrical current. In a solar cell, p-type and n-type silicon are sandwiched together to create a <b>p-n junction</b>, as shown in Figure 1 (Locke, 2008). The p-type area is positively charged,  and the n-type area is negatively charged.


Older solar panels use large crystalline structures made from silicon. When sunlight hits the silicon on the solar panel, the photons from the sunlight energize the electrons in the material. These energized electrons create a higher electrical potential in the material that is measured as a voltage between that material and ground.
When sunlight hits the silicon on the solar panel, the photons from the sunlight energize the electrons in the material. The electrons within the crystal move to a higher energy level, creating holes. If the p-type and n-type silicon are connected with a wire, the electrons will flow from the n-type layer to the p-type layer, and electrical current is generated.


The material copper indium gallium (di)selenide (CIGS) is also used in the production of solar panels. Panels made from CIGS have a smaller crystalline structure and are less expensive than their silicon counterparts. CIGS panels are relatively flexible and can easily be shaped into flexible films. The use of CIGS to make solar panels is referred to as thin-film solar technology because of its flexible nature. CIGS panels are not as good at converting absorbed light into electrical current compared to silicon. But for mass production purposes, CIGS solar panels are the more cost effective approach to produce solar panels for frequent use (Locke, 2008).
[[Image:Lab_renewener_01.png|thumb|500px|center|Figure 1: A Silicon Solar Panel Showing the Electron Flow]]


=== Wind Energy ===
=== Wind Energy ===


<b>Wind turbines</b> are used to capture the wind’s energy and convert it into electrical energy. The blades on wind turbines are slanted so that as the wind passes over the blades it creates an uneven pressure on each side, causing them to rotate. The spinning blades drive a low speed shaft connected to a gearbox. The gearbox within the wind turbine converts the low speed rotation to a high speed rotation through a high speed shaft. The high speed shaft is connected to a brake and then into an electrical generator where mechanical energy is converted to electrical energy (Layton, 2011).
<b>Wind turbines</b> are used to capture the wind’s energy and convert it into electrical energy. The blades on wind turbines are slanted so that as the wind passes over the blades, it creates an uneven pressure on each side, causing them to rotate. The spinning blades drive a low speed shaft connected to a gearbox. The gearbox converts the low speed rotation to a high speed rotation through a high speed shaft. The high speed shaft is connected to a brake and then into an electrical generator where mechanical energy is converted to electrical energy (Layton, 2011).


A basic electrical generator is made of permanent magnets on each side with a rectangular coil connected to a commutator, which is a rotary electrical switch (Figure 2). The two permanent magnets on each side create a magnetic field. As the rectangular coil spins mechanically, the magnetic field through the area of the coil changes, creating an alternating current through the coil. The commutator switches the polarity of the coil just as the polarity of the alternating current changes, creating a direct current. The current is then output from the wind turbine (Layton, 2011).
A basic electrical generator is made of permanent magnets on each side with a rectangular coil connected to a commutator, which is a rotary electrical switch (Figure 2). The two permanent magnets on each side create a magnetic field. As the rectangular coil spins mechanically, the magnetic field through the area of the coil changes, creating an alternating current through the coil. The commutator switches the polarity of the coil just as the polarity of the alternating current changes, creating a direct current. The current is then output from the wind turbine (Layton, 2011).


[[Image:Lab_renewener_02.png|thumb|500px|center|Figure 2: The Internal Structure of an Electrical Generator (Layton, 2011)]]
[[Image:Lab_renewener_02.png|thumb|500px|center|Figure 2: The Internal Structure of an Electrical Generator (Layton, 2011)]]
<!--==== Hydroelectric Power ====
<!--==== Hydroelectric Power ====
Water is constantly moved around in various states through the water cycle. Water evaporating from Earth’s surface condenses into clouds. The water in clouds over land will eventually precipitate in the form of rain effectively transporting water to a higher elevation and thus potential energy state. The energy is then release in the form of water flowing downstream. This movement provides opportunities to harness a seemingly infinite source of kinetic energy. In order to generate sufficient electricity from the motion of the water, it has to move fast enough and in large enough volumes to spin a turbine. The turbines used for hydroelectric energy operate in an almost identical manner to the turbines for used for wind power. The only differences occur in the physical construction of the turbine itself. In order to increase the volumes and motion of the water dams are created to store reservoirs of water.
Water is constantly moved around in various states through the water cycle. Water evaporating from Earth’s surface condenses into clouds. The water in clouds over land will eventually precipitate in the form of rain effectively transporting water to a higher elevation and thus potential energy state. The energy is then release in the form of water flowing downstream. This movement provides opportunities to harness a seemingly infinite source of kinetic energy. In order to generate sufficient electricity from the motion of the water, it has to move fast enough and in large enough volumes to spin a turbine. The turbines used for hydroelectric energy operate in an almost identical manner to the turbines for used for wind power. The only differences occur in the physical construction of the turbine itself. In order to increase the volumes and motion of the water dams are created to store reservoirs of water.
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== Energy Storage ==
== Energy Storage ==


<b>Capacitors</b> have many uses in circuits and signal processing. In this lab, a capacitor can be used as the power source for the renewable energy vehicle. Fundamentally, a capacitor is an electrical device that is used to store charge temporarily. Some capacitors can be used in place of a battery, but they operate very differently from a battery. A capacitor is charged by a voltage source logarithmically, as shown in Figure 3.
<b>Capacitors</b> have many uses in circuits and signal processing. A capacitor is an electrical device that is used to store charge temporarily. In this lab, a capacitor will be used as the power source for the renewable energy vehicle. A capacitor is charged by a voltage source logarithmically, as shown in Figure 3.
   
   
[[Image:Lab_renewener_06.png|thumb|500px|center|Figure 3: Capacitor Charging Curve]]
[[Image:Lab_renewener_06.png|thumb|500px|center|Figure 3: Capacitor Charging Curve]]


Because of their design, these capacitors are sensitive to the polarity of the voltage applied to them. The capacitors used in this lab must be connected with the proper polarity. In the lab, the capacitor’s negative lead must be connected to the negative applied voltage (Figure 4). Failure to do this will cause the capacitor to fail.
Because of their design, capacitors can be sensitive to the polarity of the voltage applied to them. The capacitors used in this lab must be connected with the proper polarity. In this lab, the capacitor’s negative lead must be connected to the negative applied voltage (Figure 4). Failure to do this will cause the capacitor to fail.
   
   
[[Image:Lab_renewener_07.png|thumb|500px|center|Figure 4: Polarized Capacitor]]
[[Image:Lab_renewener_07.png|thumb|500px|center|Figure 4: Polarized Capacitor]]


The energy a capacitor holds is proportional to the square of the voltage across the capacitor (1).
The energy a capacitor holds is proportional to the square of the voltage across the capacitor (1). In (1), E is the energy, C is the capacitance, and V is the voltage.


<center><math>E = \frac{CV^2}{2}\,</math></center>
<center><math>E = \frac{CV^2}{2}\,</math></center>
<p style="text-align:right">(1)</p>
<p style="text-align:right">(1)</p>


In (1), E is the energy, C is the capacitance, and V is the voltage. The capacitance value of a capacitor is measured in farads (F) and energy is measured in joules (J).
== Electrical Components ==
 
The design of a circuit determines its behavior. In this lab, one circuit design will increase the speed output of a motor and the other will increase the torque output of a motor. In electrical engineering, different electrical components are represented by different symbols. Figures 5 show the symbols for a <b>capacitor</b>, <b>DC source</b>, and <b>battery</b>. They are all forms of energy storage devices.


== Electrical Components ==
[[Image:Symbol_for_Capacitor_Battery_DC_Source.png|center|thumb|400px|Figure 5: (left to right) The Symbol for a Capacitor, DC Source, and a Battery]]
The design of a circuit determines its behavior. In this lab, one circuit design will increase the speed output of a motor and the other will increase the torque output of a motor. In electrical engineering, different electrical components are represented by different symbols. Figures 5A, 5B, and 5C show the symbols for a <b>battery</b>, <b>capacitor</b>, and <b>DC source</b>, respectively. They are all forms of energy storage devices.


[[Image:Lab_renewener_05.png|center|thumb|79px|Figure 5A: Symbol for Battery]]
Different arrangements of electrical components allow engineers to design different circuits which can be arranged in two different ways. In a <b>series circuit</b>, the circuit's components are connected end to end (Figure 6). The current in a series circuit remains the same in all the electrical elements.  
[[Image:Capacitor Symbol.png|center|thumb|79px|Figure 5B: Symbol for Capacitor]]
[[Image:DC Source.png|center|center|thumb|79px|Figure 5C: Symbol for DC Source]]
<!--<b>Diodes</b> and <b>light emitting diodes (LEDs)</b> were introduced in the Prototyping with Microcontrollers, Sensors, and Materials lab. A diode has polarity and will only allow current to pass from its positive lead to its negative lead. A light emitting diode (LED) not only passes current, but also lights up when it is passing current. LEDs have a forward voltage and a reverse voltage. In the forward direction, the forward voltage and resistance are low and determined by the material used in the LED. The reverse voltage has a much higher resistance and a higher reverse voltage that prevents the flow of electrical current. The characteristic of the diode is to have low resistance to electrical flow in the forward direction and high resistance in the reverse direction. This provides the ability to control the flow of electricity in one direction only.


There is a threshold voltage in the forward direction for the LED to emit light. Below the threshold voltage, there is no light. At and above the threshold voltage, the LED emits light with intensity roughly linear with the forward voltage magnitude. The symbol for an LED is shown in Figure 6.
[[Image: Series_Circuit.png|thumb|300px|center|Figure 6: A Series Circuit]]


[[Image:Symbol_LED.png|thumb|center|150px|Figure 6: Symbol for LED]]-->
In a series circuit, the sum of the voltages across each element is equal to the voltage of the power source (2). Note that there is a single path for current to flow through. In (2), V<sub>out</sub> is the voltage output and V<sub>A</sub>, V<sub>B</sub>, and V<sub>C</sub> represent the voltage of the individual components.  
Different arrangements of electrical components allow engineers to design different devices. Components, such as resistors, inductors, and capacitors, can be arranged in two different ways. In a <b>series circuit</b>, the element's components are connected end to end. The current in a series circuit remains the same in all the electrical elements. In a series circuit, as shown in Figure 6, the sum of the voltages across each element is equal to the voltage of the power source (2).


<center><math>V_{out} = V_A + V_B + V_C</math></center>
<center><math>V_{out} = V_A + V_B + V_C</math></center>
<p style="text-align:right">(2)</p>
<p style="text-align:right">(2)</p>


In (2), V<sub>out</sub> is the voltage output and V<sub>A</sub>, V<sub>B</sub>, and V<sub>C</sub> represent the voltage of the individual components.


[[Image:Lab_renewener_08.png|thumb|500px|center|Figure 6: A Series Circuit]]
In a <b>parallel circuit</b>, as shown in Figure 7, the circuit's components are connected at opposing ends. The current that is supplied by the voltage source equals the current that flows through elements D and E.
 
[[Image:Parallel_Circuit.png|thumb|300px|center|Figure 7: A Parallel Circuit]]


In a <b>parallel circuit</b>, as shown in Figure 7, the element's components are connected at opposing ends. The current that is supplied by the voltage source equals the current that flows though elements D and E. The voltage across the elements that are parallel is the same (3).
The voltage across the elements that are parallel is the same (3). In comparison to a series circuit, a parallel circuit has multiple paths for the current to flow through. In (3), V<sub>out</sub> is the voltage output and V<sub>D</sub> and V<sub>E</sub> represent the voltage of the individual components.


<center><math>V_{out} = V_D = V_E</math></center>
<center><math>V_{out} = V_D = V_E</math></center>
<p style="text-align:right">(3)</p>
<p style="text-align:right">(3)</p>


In (3), V<sub>out</sub> is the voltage output and V<sub>D</sub> and V<sub>E</sub> represent the voltage of the individual components.  
For most circuits, they contain both series and parallel components. The parallel components  can be thought of as branches, and each branch contains its own series circuit. Figure 8 shows a circuit that contains both series and parallel components. There are two branches, one on the left and the right. The branch on the right contains only series connections, while the branch on the left contains both series and parallel connections.
[[Image:Lab_renewener_09.png|thumb|500px|center|Figure 7: A Parallel Circuit]]


A <b>digital multimeter</b> will be used in this lab to read the current and voltage across components in circuits. Multimeters usually have two leads that directly touch two nodes in a circuit or the leads of an electrical component. Please read the [[media: DMMGuidelines.docx | Digital Multimeter Guidelines]] before performing this lab in order to understand how to properly operate a digital multimeter. Digital multimeters are indicated by different symbols in electrical circuits, depending on the value being measured by the multimeter. When measuring voltage, the multimeter is referred to as a voltmeter (Figure 8A). When measuring current, the multimeter is referred to as an ammeter (Figure 8B).
[[Image:Series_Parallel_Circuit.png|thumb|300px|center|Figure 8: A Circuit that Contains Components in Parallel and Series]]


[[Image:Voltmeter Symbol.png|thumb|150px|center|Figure 8A: Symbol for Voltmeter]]
Using knowledge of series and parallel connections, the voltage V<sub>out</sub> can be calculated. Since V<sub>4</sub> and V<sub>5</sub> are in series, the voltage V<sub>out</sub> must be equal to V<sub>4</sub> + V<sub>5</sub> (4).  
[[Image:Ammeter Symbol.png|thumb|150px|center|Figure 8B: Symbol for Ammeter]]


Depending on whether voltage or current is being measured in a circuit, the multimeter will be arranged in the circuit in a different manner. To measure the voltage across an electrical component, the multimeter must be placed in the circuit in parallel (Figure 9A). To measure the current across an electrical component, the multimeter must be placed in the circuit in series (Figure 9B).
<center><math>V_{out} = V_4 + V_5</math></center>
 
[[Image:Multimeter in Parallel.png|thumb|362px|center|Figure 9A: Multimeter in Parallel]]
[[Image:Multimeter in Series.png|thumb|362px|center|Figure 9B: Multimeter in Series]]
 
After measuring the voltage and current across a component in a circuit, the electrical <b>power</b> output of that component can be calculated using the Power Law (4).
 
<center><math>P = IV</math></center>
<p style="text-align:right">(4)</p>
<p style="text-align:right">(4)</p>


In (4), P is the power in Watts, I is the current in Amperes, and V is the voltage in Volts.
Additionally, V<sub>1</sub> and V<sub>2</sub> are in parallel, meaning that their voltages are the same. Knowing this, and that V<sub>3</sub> is in series with the parallel circuit, V<sub>out</sub> can be calculated in a different way (5).


<!--The <b>motor</b> provided in the lab is a 9V motor that will operate with voltages lower than 9V with reduced torque and speed (Figure 10). A motor with no load draws 9 mA, and a stalled motor draws well over 350 mA. Increasing the voltage provided to the motor increases the speed. Increasing the current increases the torque.
<center><math>V_{out} = V_1 + V_3 = V_2 + V_3</math></center>
<p style="text-align:right">(5)</p>


[[Image:LEGO 9V Motor.jpg|thumb|200px|center|Figure 10: LEGO 9V Motor]]-->
A <b>digital multimeter</b> will be used in this lab to read the current and voltage across components in circuits. Please read the [[Digital Multimeters Guidelines]] before performing this lab to understand how to properly operate a digital multimeter. Digital multimeters can measure either voltage or current, indicated by the symbols shown in the circuit diagram (Figure 9).
== VEX Robotics ==
Vex Robotics is used globally for students to understand the fundamentals of robotics. It is commonly used to model the capabilities of vehicles.
In this lab, you will be using VEX robotics parts in order to construct the chassis in Fusion 360.
The <b>motor</b> used in the lab is a 9V VEX motor.


[[Image:Vex_image.png|thumb|200px|center|Figure 10: 9V VEX Motor]]
[[Image:Symbol_for_Voltmeter_and_Ammeter.png|thumb|300px|center|Figure 9: (l-r) Symbols for a Voltmeter and Ammeter]]


<!--== Fusion 360 ==
Depending on whether voltage or current is being measured in a circuit, the multimeter will be arranged in the circuit in a different manner. To measure the voltage across an electrical component, the multimeter must be placed in the circuit in parallel (Figure 10).  
A brief digest of the tools and functions of the Fusion 360 Design workspace is presented below. This digest is specific to this virtual lab and many of the CAD functions can be performed differently in other situations.


===  Navigation Tools  ===
[[Image:Multimeter_in_Parallel.png|thumb|362px|center|Figure 10: Multimeter in Parallel]]
* The <b>Orbit</b> tool allows rotating the current view around a pivot point in three dimensions. This can also be done by grabbing the orthographic cube in the top right corner and rotating it. To make the view normal to a face, edge, or corner, click the respective part of the orthographic cube.
* The <b>Zoom tool</b> allows for the magnifying or minimizing of an object.  
* If the component is lost in the view, either use the <b>Pan tool</b> to move the current view in 2D until it is found, or click Zoom Window > Fit. These tools will help navigate the workspace while putting together the boom.


[[Image:Bc1.png|300px|thumb|center|Figure 11: Orbit, Pan and Zoom Tools]]
To measure the current across an electrical component, the multimeter must be placed in the circuit in series with the component (Figure 11). As described in the [[Digital Multimeters Guidelines]], ensure the leads are connected to the correct multimeter ports depending on which value is being measured.


===  Moving Components  ===
[[Image:Multimeter_in_Series.png|thumb|362px|center|Figure 11: Multimeter in Series]]
* Once a component is placed into the workspace, Fusion 360 will remember the component in that space. To move it again, use the <b>Move/Copy tool</b> after right clicking the component (Figure 12).


[[Image:Bc2.png|400px|thumb|center|Figure 12: Move/Copy Tool]]
After measuring the voltage and current across a component in a circuit, the electrical <b>power</b> output of that component can be calculated using the Power Law (6). In (6), P is the power (Watts), I is the current (Amperes), and V is the voltage (Volts).


<center><math>P = IV</math></center>
<p style="text-align:right">(6)</p>


* Once the component is moved to the desired position, use the <b>Capture Position tool</b> to set the component in that place (Position > Capture Position). If it is ever moved unintentionally, use the <b>Revert button</b> (Position >  Revert) to move the component back to its original position. These tools will only show up when the model is an unsaved position (Figure 13).
The motor provided in the lab is a 9 V DC motor that will operate with voltages no more than 9 V with reduced torque and speed (Figure 12). A motor with no load operates under the current of 9 mA, and a stalled motor operates under the current of over 350 mA. Increasing the voltage provided to the motor increases the speed. Increasing the current, increases the torque.


[[Image:Bc3.png|450px|thumb|center|Figure 13: Capture Position Tool]]
[[Image:LEGO 9V Motor.jpg|thumb|200px|center|Figure 12: LEGO 9V Motor]]


===  Deleting Components  ===
To increase the torque or speed of a power source, gear ratios can be used. When connecting two gears with different teeth counts, the rotational speeds of the gears differ. The gear ratio is used to calculate the ratio of rotational speeds of different gears based on the number of teeth of each gear (7).  
* Deleting parts requires an extra step. Clicking on an object automatically selects the face of a body and not the whole body, and Fusion 360 will not be able to delete a face. To get past this, in the toolbar go to Select > Selection Priority > Select Body Priority (Figure 14).


[[Image:Bc4.png|700px|thumb|center|Figure 14: Select Tool]]
<center><math>Gear\ Ratio = \frac{Teeth_{\text{out}}}{Teeth_{\text{in}}}\,</math></center>
<p style="text-align:right">(7)</p>


* A part can only be deleted by selecting its body. Make sure to use the same steps to change the selection priority back to face, or to edge/component if necessary. Another way to delete is to right click on the component in the Browser tab and click Delete.
Teeth<sub>out</sub> is the gear that is receiving rotational energy and Teeth<sub>in</sub> is the gear that it is controlling. As the gear ratio increases, the output gear spins slower. A gear ratio of 2 means that the input gear must spin two times for the output gear to spin once, a ratio of 3 means the input gear must spin three times, and so on.


===  Aligning Components  ===
Figure 13 shows three gears with different ratios. Taking the red gear to be the input gear, there is a large gear ratio between the red gear and the blue gear it is driving. The blue gear spins much slower, and it transfers that rotation to the yellow gear. Again, there is a large gear ratio between the yellow and green gears, and so the green gear spins even slower.
* The <b>Align tool</b> is found under the Modify tab of the toolbar. This is useful when attempting to place cylinders in a position defined by an opening. Simply select the outside face of the cylinder and the inside face of the hollow cylinder to align the two parts. Make sure to check the <b>Capture Position Box</b> or use the <b>Capture Position tool</b> to save this setup of the model (Figure 15).


[[Image:Bc51.png|700px|thumb|center|Figure 15: Align Tool]]
[[Image:Gear_Ratio_Demonstration.gif|thumb|400px|center|Figure 13: Gear Ratio Demonstration (Wikipedia Commons)]]
 
Here's a video tutorial on how to  use the align tool:
[https://drive.google.com/file/d/1APz_kDAN3bZ4s7QPy4O5GOm3jZdfOs4G/view?usp=sharing Align tool tutorial]
Download the video is it does not play in the browser.-->


= Design Considerations =
= Design Considerations =
* Which source yields the most voltage per unit cost?
* Which source yields the most voltage per unit cost?
* Which circuit configuration will provide the most desirable voltage across the load? Parallel or series?
* Which circuit configuration will provide the most voltage across the load? Parallel or series?
* Which aspects of the competition formula are most advantageous?


= Materials and Equipment =
= Materials and Equipment =
<!--=== Materials with Price List ===
=== Materials with Price List ===
{| class="wikitable"
{| class="wikitable"
|+ Table 1: Materials and Costs
|+ Table 1: Materials and Costs
Line 160: Line 139:
|style="text-align: center;"|Solar Panel||style="text-align: center;"|1||style="text-align: center;"|$10.00
|style="text-align: center;"|Solar Panel||style="text-align: center;"|1||style="text-align: center;"|$10.00
|-
|-
|style="text-align: center;"|1 F 5.5V Capacitor||style="text-align: center;"|1||style="text-align: center;"|$3.00
|style="text-align: center;"|1 F 2.7 V Capacitor||style="text-align: center;"|1||style="text-align: center;"|$3.00
|-
|-
|style="text-align: center;"|Alligator Clip Set||style="text-align: center;"|1 pair||style="text-align: center;"|$0.50
|style="text-align: center;"|Alligator Clip Set||style="text-align: center;"|1 pair||style="text-align: center;"|$0.50
Line 170: Line 149:
|style="text-align: center;"|Tape||style="text-align: center;"|1 foot||style="text-align: center;"|$0.10
|style="text-align: center;"|Tape||style="text-align: center;"|1 foot||style="text-align: center;"|$0.10
|-
|-
|}-->
|}
 
=== Equipment Used ===
* Horizon wind-turbine
* Horizon wind-turbine
* Sunforce 50013 1 W solar battery charger
* Sunforce 50013 1 W solar battery charger
* Adjustable table fan
* Adjustable table fan
* Heat lamp
* Heat lamp
* 3V power supply
* 3 V power supply
* Digital multimeter
* Digital multimeter
* Music voltmeter
* Piezo buzzer
* 9V DC motor
* 9 V DC motor
* 1 F 5.5V capacitor
* A 1 F 2.7 V capacitor
* 3 alligator clip sets
* Three alligator clip sets
* Virtual VEX Kit
* Standard LEGO kit
* Lego to alligator clip connector
* Scissors
* Tape


= Procedure =
= Procedure =


This lab is divided into 4 sections:
The power storage device and power sources will be tested individually. The results of the tests will be used in determining the best power source for the sustainable energy vehicle.
* The testing of the power storage device
* The investigation of renewable energy sources
* The fabrication of a sustainable energy vehicle
* The data analysis of the United States’ renewable energy consumption
The power storage device and power sources will be tested individually. The results of the tests will be used in determining the best power source which will be chosen to design the sustainable energy vehicle.
 
== Note for Hybrid Session ==
In-person students are expected to complete the physical circuits for Part 1 and Part 2, indicated by the label <b>(In-Person)</b>. Remote students are expected to complete a similar circuit diagram via Tinkercad for Part 1 and Part 2 of the procedure. In-depth instructions on the Tinkercad circuits are provided under the physical procedures with the label <b>(Remote)</b>. Any procedure labeled <b>(Hybrid)</b> is expected to be completed through a joint collaboration between remote and in-person students.
 
In order to create new circuits or copy an existing template of a circuit in Tinkercad, follow the steps below:
 
* Go to tinkercad.com and sign in with an Autodesk account.
* To start a new circuit, on the left side of the home screen select Circuit > Create new circuit.
* If a template link is provided in the procedure:
** Open the Tinkercad link for the part of the lab you want to work on. The links are provided in the procedure below.
** Select the Copy & Tinker option. This will copy the template to the workspace so it can be edited.


== 1. Testing the Power Storage Device ==
== 1. Testing the Power Storage Device ==
During this part of the procedure, a capacitor will be charged and discharged with a piezo buzzer. The current of the circuit with two capacitors, a piezo buzzer, and a multimeter in series and in parallel will be measured.


=== Charging a Capacitor (In-Person) ===
=== Charging a Capacitor ===


# The circuit in Figure 16 will be created to charge a capacitor. Connect an alligator clip to each of the cables coming out of the 3V power supply. Red is the positive terminal and black is the negative terminal.
# The circuit in Figure 14 will be created to charge a capacitor. Connect an alligator clip to each of the cables coming out of the 3 V power supply. Red is positive and black is negative.[[Image:Circuit_to_Charge_a_Capacitor_.jpeg|thumb|500px|center|Figure 14: Circuit to Charge a Capacitor]]
# Connect one of the unconnected alligator clips to one of the leads of the ammeter (the multimeter set to measuring current).
# Connect one of the unconnected alligator clips to one of the leads of the ammeter (the multimeter set to measuring current).
# Connect the rest of the unconnected cables (one from the ammeter and one alligator clip) in series to the leads of the capacitor with the polarity indicated in Figure 16.
# Connect the rest of the unconnected cables (one from the ammeter and one alligator clip) in series to the leads of the capacitor with the polarity indicated.
# Charge the capacitor until the current in the circuit is zero.
# Charge the capacitor until the current in the circuit is near 0 A.
# Discharge the charged capacitor by connecting it to the music voltmeter. The capacitor is discharging when the music voltmeter audibly plays a song.
# Discharge the charged capacitor by connecting it to the piezo buzzer. The capacitor is discharging when the piezo buzzer makes a noise.  


[[Image:Lab 10 Figure 8.png|thumb|500px|center|Figure 16: Circuit to Charge a Capacitor]]
=== Power Output of Capacitors in Series and Parallel ===
# Charge a capacitor until fully charged using the battery. 
# Set the capacitor aside in a safe place. Be careful not to discharge it when moving.
# Get a new capacitor and fully charge it.
# Wire the two capacitors, the buzzer, and the multimeter in series. Only connect the capacitors long enough to record your measurement. Recharge the capacitors between measurements.
## Refer to the schematic in Figure 15.
## Remember to check for the proper polarity, otherwise the circuit will not run
[[Image:Series_Capacitor.png|thumb|500px|center|Figure 15: Series Capacitors Current Circuit]]
 
<ol start="5">
<li>Record the current produced by the circuit in series.</li>
<li>Record the voltage across the piezo buzzer.
<ol>
<li>Refer to the schematic in Figure 16. </li>
<li>Remember to check for the proper polarity, otherwise the circuit will not run</li>
</li>
</ol>
[[Image:Voltage_Circuit.png|thumb|500px|center|Figure 16: Series Capacitors Voltage Circuit]]


=== Charging a Capacitor (Remote) ===
</ol>
<ol start="7">
<li>Repeat steps 1-3.</li>
<li>Wire the two capacitors, the buzzer, and the multimeter in parallel.
<ol>
<li>Refer to the schematic in Figure 17. </li>
</li>
</ol>


# Open a new Tinkercad circuit. Refer to the starting the new Tinkercad circuit procedure given above.
[[Image:Parallel_Capacitors.png|thumb|500px|center|Figure 17: Parallel Capacitors Circuit]]
# The circuit to charge a capacitor will be made in this part of the lab. The circuit is shown in Figure 17.
# Click and drag a 9V battery, 1 Farad capacitor, and multimeter on the interface as shown in Figure 17
# Wire the negative end of the 9V battery to the negative end of the multimeter. To wire these two components, simply click on the negative terminal of the battery, and click once again on the negative terminal of the multimeter. Red is the positive terminal and black is the negative terminal.
# Similarly, wire the positive end of the multimeter to terminal 1 on the capacitor. Wire terminal 2 on the capacitor to the positive terminal of the battery.
# To charge the capacitor click Start Simulation. Charge the capacitor until the current in the circuit is zero ampere (0A).
# Click on Stop Simulation once the multimeter reading is zero ampere (0A).
# Take a screenshot of your circuit.


[[Image:Unnamed.png|thumb|500px|center|Figure 17: Tinkercad Circuit to Charge a Capacitor]]
</ol>
<ol start="9">
<li>Draw a schematic for a circuit that will measure the current through the piezo buzzer with capacitors in parallel. '''Get a TA’s approval for  the schematic.'''</li>
<li>Create the circuit and record the current through the buzzer.</li>
<li>Calculate the power output for capacitors connected in series and capacitors connected in parallel.</li>
</ol>


== 2. Testing the Power Sources ==
== 2. Testing the Power Sources ==
<!--One type of renewable power source will be assigned and analyzed per team, as determined by the TA. Both voltage and current must be measured and recorded, and power must be calculated.
 
One type of renewable power source will be assigned and analyzed. Using the digital multimeter, both voltage and current must be measured and recorded, and the power output must be calculated.


=== Wind Turbine ===
=== Wind Turbine ===
# Connect the wind turbine to the music voltmeter using the alligator clips. Measure the voltage and current across the music voltmeter using the digital multimeter. The connections for measuring voltage and current across the music voltmeter are shown in Figures 9A and 9B.
# Connect the wind turbine to the piezo buzzer using the alligator clips following the schematic presented earlier. Measure the voltage and current across the piezo buzzer using the digital multimeter.  
# Adjust the position of the turbine blades against the wind to find the highest voltage and current that can be generated.
# Adjust the position of the turbine blades near the fan to find the highest voltage and current that can be generated.
# Calculate and record the power generated by the turbine and give the information to a TA.
# Calculate and record the power generated by the turbine and give the information to a TA (Figures 18-19).


=== Solar Panel ===
[[File: Measure_Voltage_of_Wind_Turbine.png|400px|thumb|center|Figure 18: Circuit to Measure Voltage of the Wind Turbine]]
# Connect the solar panel to the music voltmeter using the alligator clips. Place the solar panel near the heat lamp and measure the voltage and current across the music voltmeter using the digital multimeter.
# Adjust the position of the solar panel to find the highest voltage and current that can be generated.
# Calculate and record the power generated by the solar panel and give the information to a TA.
'''<span style="color: red">Caution!</span> The heat lamps and solar panels may become extremely hot when used for a long duration of time. Do not touch them immediately after use and turn them off when not in use.'''
==== Hydroelectric Turbine ====
# Connect the red wire of the water wheel to the positive (red) end of the multimeter and the black wire to the negative (black) end of the multimeter. Set the multimeter to measure voltage.
# Notify the TA once the connections have been set up. The TA will then take you to the AUV room's sink to measure the voltage and (electrical) current produced by the water coming from the sink. '''<span style="color: red">Be very careful to keep water off of the multimeters.</span>'''
# Calculate and record the power generated by the water wheel and give information to the TA.-->


<!--=== Competition Rules ===
[[File: Measure_Current_of_Wind_Turbine.png|400px|thumb|center|Figure 19: Circuit to Measure Current of the Wind Turbine]]


The competition rules must be followed at all times during the competition. Violation of any of these rules will result in the disqualification of the design.
=== Solar Panel ===


* The renewable energy vehicle must carry its power storage device (e.g. capacitor)
# Connect the solar panel to the piezo buzzer using the alligator clips. Place the solar panel near the heat lamp and measure the voltage and current across the music voltmeter using the digital multimeter.
* The capacitor can only be charged using the power sources provided
* Each design will only be allowed one trial
* Do not touch the leads of the charged capacitor - this will discharge the capacitor
* Do not connect the power storage device until immediately before the trial is run
* The trial will end after five minutes or when the car stops moving, whichever occurs first
* The highest competition ratio (CR) wins (5)
<center><math>CR = \frac{Distance\left[\text{ft}\right]}{1\left[\text{s}\right] + Time\left[\text{s}\right]} \times \frac{100}{Cost\left[$\right]} + Distance\left[\text{ft}\right]\,</math></center>
<p style="text-align:right">(5)</p>
 
In (5), distance is distance traveled in feet, time is the travel time in seconds, and cost is the cost of the design in dollars.-->
 
<!--=== 3. Sustainable Energy Vehicle Competition ===
 
# Assess the materials and consider the data from 1. Testing the Power Storage Device and 2. Testing the Power Sources. Choose materials for the vehicle design, keeping in mind the competition ratio. Make preliminary sketches during this process.
# The design must hold the power storage device on top of it during the trials. Modify the design to fit the power storage device, keeping in mind where the wires will be when the trial is run. Prepare a cost list for the renewable energy vehicle based on the design and materials chosen. Have a TA sign the sketches and the cost list, indicating the total cost of the initial design.
# A TA will provide the materials needed for the design. If the design is modified during the construction, note the changes and describe the reasons for them. If the modifications required more materials to be used, update the cost list and have a TA approve it.
# Construct the vehicle based on the sketched design.
# Run the trial.
# Give the total cost of the design to a TA. The TA will provide the competition ratio obtained.
 
'''Before entering the competition, test the motor and cable. Make sure the motors turn in the desired direction of travel.'''-->
 
Four sources of energy will be analyzed in this part of the procedure: a wind turbine, a solar panel, a lemon battery, and a potato battery.<b> The in-person students are responsible for building a circuit for and analyzing either the wind turbine or the solar panel, as determined by the TA. The remote students are responsible for building a circuit for and analyzing both the lemon and potato battery via Tinkercad.</b>  All voltage and current must be measured and recorded, and power must be calculated. <b>Remote and in-person students (from the same group) will compare the data collected. Based on the results recorded, each group will choose a suitable power source from all four options.</b>
 
=== Wind Turbine (In-Person) ===
 
# Connect the wind turbine to the music voltmeter using the alligator clips. Measure the voltage and current across the music voltmeter using the digital multimeter. The connections for measuring voltage and current across the music voltmeter are shown in Figures 9A and 9B.
# Adjust the position of the turbine blades against the wind to find the highest voltage and current that can be generated.
# Calculate and record the power generated by the turbine and give the information to a TA.
 
=== Solar Panel (In-Person) ===
 
# Connect the solar panel to the music voltmeter using the alligator clips. Place the solar panel near the heat lamp and measure the voltage and current across the music voltmeter using the digital multimeter.
# Adjust the position of the solar panel to find the highest voltage and current that can be generated.
# Adjust the position of the solar panel to find the highest voltage and current that can be generated.
# Calculate and record the power generated by the solar panel and give the information to a TA.
# Calculate and record the power generated by the solar panel and give the information to a TA (Figure 20).


=== Lemon Battery (Remote) ===
[[File: Measure_Voltage_of_Solar_Panel.png|400px|thumb|center|Figure 20: Circuit to Measure Voltage of the Solar Panel]]


# Click and drag two lemon batteries and a multimeter on the interface. If the lemon battery is not visible in the components menu on the right, click on Components > All.
[[File: Measure_Current_of_Solar_Panel.png|400px|thumb|center|Figure 21: Circuit to Measure Current of the Solar Panel]]
# Create a circuit using two lemon batteries. Wire the multimeter to be in series with the circuit.
# Click on Start Simulation and record the final current produced by the circuit in series.
# Create a circuit using two lemon batteries. Wire a multimeter in parallel to the circuit. In order to create the circuit, diodes are required to connect more than two wires.
# Click on Start Simulation and record the final voltage produced by the circuit in parallel.
# Make sure to wire the positive terminal of the lemon battery with the positive terminal of the multimeter and the negative terminal of the lemon battery to the negative terminal of the multimeter.
# Take a screenshot of both the circuits with the voltage and current reading.
# Calculate and record the power generated by the solar panel and give the information to a TA.
# If you finished both the lemon battery circuit and the potato battery circuit before the in-person students finished their circuit, move on to Part 3 of the procedure in order to familiarize yourself with the given VEX parts and the align tool. Once the in-person students finished their circuit, everyone in the group should collaborate to complete the Data Analysis portion of Part 2.


=== Potato Battery (Remote) ===
=== Data Analysis ===


# Click and drag two potato batteries and a multimeter on the interface. If the potato battery is not visible in the components menu on the right, click on Components > All.
# The TA will display the power data from each renewable energy source on the board. Based on the power output of each renewable energy source and the analysis of the circuits in series and parallel, determine the best power source and circuit design to power a sustainable energy vehicle with two capacitors.
# Create a circuit using two potato batteries. Wire the multimeter to be in series with the circuit.
# Click on Start Simulation and record the final current produced by the circuit in series.
# Create a circuit using two potato batteries. Wire a multimeter in parallel to the circuit. In order to create the circuit, diodes are required in order to connect more than two wires.
# Click on Start Simulation and record the final voltage produced by the circuit in parallel.
# Make sure to wire the positive terminal of the potato battery with the positive terminal of the multimeter and the negative terminal of the potato battery to the negative terminal of the multimeter.
# Take a screenshot of both the circuits with the voltage and current reading.
# Calculate and record the power generated by the solar panel and give the information to a TA.


<b>If you finished both the lemon battery circuit and the potato battery circuit before the in-person students finished their circuit, move on to Part 3 of the procedure in order to familiarize yourself with the given VEX parts and the align tool. Once the in-person students finished their circuit, everyone in the group should collaborate to complete the Data Analysis portion of Part 2.</b>
'''<span style="color: red">Caution! The heat lamps and solar panels may become extremely hot when used for a long duration of time. Do not touch them immediately after use and turn them off when not in use.'''</span>


=== Data Analysis (Hybrid) ===
== Competition Rules ==


# Share and explain the circuits built and the data collected for the wind turbine, solar panel, lemon battery, and potato battery to your group.
The competition rules must be followed at all times during the competition. Violation of any of these rules will result in the disqualification of the design.
# Based on the calculated power of each renewable energy source, determine the best power source in order to theoretically power a sustainable energy vehicle. <b>Remote and in-person students have the option of choosing from all four options (solar panel, wind turbine, potato battery and lemon battery) regardless of the specific power source that they tested. </b>
# With the chosen power source, create a circuit that would charge the capacitor. Use a multimeter to confirm that the capacitor is charged. The circuit should be made in person if the chosen power source is a wind turbine or a solar panel and should be made in Tinkercad if the chosen power source is a lemon or a potato battery.
<b>Caution! The heat lamps and solar panels may become extremely hot when used for a long duration of time. Do not touch them immediately after use and turn them off when not in use.</b>


== 3. Sustainable Energy Vehicle (Hybrid) ==
* The renewable energy vehicle must carry its power storage device (e.g. capacitor)
* The capacitors may only be connected to the power source for one minute regardless of how they are connected.
** If two capacitors are connected and charged in series, they may only charge for one minute.
** If two capacitors are charged in parallel, they may only charge for one minute.
* Each design will only be allowed one trial.
* Do not touch the leads of the charged capacitors or allow the leads to touch each other, this will discharge the capacitor.
* Do not connect the power storage device until immediately before the trial is run.
* The trial will end once the vehicle stops moving or after a maximum of 5 min.
* The design with the highest competition equation (CE) result wins (8). In (8), distance, time, and cost are measured in feet, seconds, and US dollars respectively.


In this part, a simple vehicle will be designed and assembled in Fusion 360. This vehicle will utilize one motor that is powered by the capacitors in the previous steps.
<center><math>CE = \frac{(Distance\left[\text{ft}\right])^2}{Time[\text{s}]} \times \frac{100}{Cost\left[$\right]}</math></center><p style="text-align:right">(8)</p>


=== Importing VEX Robotics Parts ===
=== 3. Sustainable Energy Vehicle Competition ===


# The VEX parts for the vehicle can be found in a ZIP folder [[Media:Sustainable_Energy_Vehicle.zip|here]]. The latest version of Fusion 360 must be downloaded for the parts to appear properly.
# Assess the materials provided and consider the data from testing the power storage device and testing the power sources. Keep in mind the variables of the competition equation while choosing materials for the vehicle design. Make preliminary sketches during this process.
# Unzip the parts to a space on the computer.
# A minimum of two capacitors must be used in the design. The vehicle must carry the power storage device during the trial. While modifying the design, keep in mind the space needed to fit the power storage device (capacitor) and its wires. Prepare a cost list of the materials used in the design and specify the total price. A TA must approve the sketches and the cost list.
# In Fusion 360, open the Data Panel (icon with 9 boxes at the top left) and click Upload (Figure 18). Select the unzipped part files to upload them to Fusion 360’s cloud memory. Fusion 360 can only import files uploaded to its cloud.
# Create a circuit diagram on paper containing the capacitors and motor. The diagram should reflect how the vehicle is wired, and should be used when constructing the vehicle. '''A TA must approve  the your circuit diagram.'''
 
# A TA will provide the materials needed for the design. If the design is modified during the construction, note the changes and explain the reasons for them. If the modifications require more materials to be used, update the cost list and have a TA approve it.
[[Image:Data_panel.png|thumb|500px|center|Figure 18: Data Panel]]
# With the chosen power source, charge the capacitors for 1 min.
 
# Construct the vehicle based on the sketched design.  
=== Design the Vehicle ===
# Before entering the competition, make sure the motors turn in the desired direction of travel.
 
# Run the trial.
Review the parts that are available. Consider the following restraints while designing your car:
# Give the total cost of the design to a TA. The TA will provide the competition equation result.
* A maximum of two motors are allowed.
* The design must be able to hold the capacitors on top of it.
* Modify the design to have a location to store the power storage device.
* The motor must be connected to a minimum of two wheels.
 
<b>Do not worry about inserting nuts and bolts. Primarily focus on the general shape of the design with shafts, wheels, and the structural components.</b>
 
=== Assemble the Parts ===
 
# Ensure that the Design workspace is open in Fusion 360. This is indicated at the top left.
# The VEX part files can be inserted into a new Fusion 360 file by simply dragging and dropping them from the Data Panel into the space. Alternatively, right click the components and select Insert into Current Design. Save the blank file before assembling the vehicle by going to File > Save as.
# Import the other parts based on the design that was sketched. Connect all the parts using the Align tool to complete the model. Use the tips from the Fusion 360 section in the Overview and watch the short tutorial on the Align Tool for instructions to properly connect the components of the vehicle in Fusion 360.
# Take screenshots of the designed vehicle in Fusion 360 and send it to the lab TA.
 
=== Extra Credit ===
To receive extra credit, create two wires using the sweep tool that connects the capacitor to a motor. Use Google, online Fusion 360 forums, and Youtube tutorials to complete this. <b>To receive extra credit, the entire vehicle design with the sweeped wires must be completed before the end of lab and also must be included in the team presentation.</b>


= Assignment =
= Assignment =
== Individual Lab Report ==
== Team Lab Report ==
<!--<b>Note:</b> You will be writing a team lab report rather than an individual one. See the [[Team Authoring Strategies]] page in the <i>Technical Communication</i> of this online manual for guidance of how to do this.-->
<!--<b>Note:</b> You will be writing a team lab report rather than an individual one. See the [[Team Authoring Strategies]] page in the <i>Technical Communication</i> of this online manual for guidance of how to do this.-->


This lab report is <b>optional</b> and you will receive <b>extra credit</b> for submitting it. {{Labs:Lab Report}}
<!--This lab report is <b>optional</b> and you will receive <b>extra credit</b> for submitting it.-->


* Define renewable energy
{{Labs:Lab Report}}
 
* Describe the rules, competition equation, and design strategy of the competition in the introduction. What consequences did the rules and competition equation have for any design decisions?
* Explain how solar panels and wind turbines work
* Explain how solar panels and wind turbines work
* Explain the concept of the capacitor
* Discuss capacitors
* Discuss the advantages and disadvantages of all four energy sources
* Discuss the advantages and disadvantages of the solar panel and wind turbine
* Describe the renewable energy vehicle design and explain the choices made in the design
* Describe the renewable energy vehicle design and explain the choices made in the design
* Discuss the power sources and their power output. How did the voltage measurements of the power sources impact the design?
* Discuss the power sources and their power output. How did the voltage measurements of the power sources impact the design?
* Discuss whether one or two motors were used in design and why
* Discuss minimal design. Were all the materials purchased used? Describe the importance of minimal design and explain how it was employed in the design. Did the design minimize cost?
* Describe how the design succeeded or failed. What choices would improve the design’s standing in the competition?
* Discuss how the competition equation can be increased, and how the design compared to the other designs
* Specify the power source chosen for the design
* Specify the power source chosen for the design
* Discuss your design. Why did you choose the chassis or wheels? How did you factor in the constraints of the vehicle?
* Include the spreadsheet with every design's results. Describe the results and talk about other designs in the competition
* Discuss how the design compared to the other designs
* Include a digital drawing of the motor circuit used in the sustainable vehicle design
* Include screenshots of the lemon and potato battery circuits and pictures of the wind turbine or solar panel circuit
* Discuss what part of the lab you completed for your group and why it was important to the overall experiment.
 


{{Labs:Lab Notes}}
{{Labs:Lab Notes}}
Line 380: Line 304:
{{Labs:Team Presentation}}
{{Labs:Team Presentation}}


* Discuss why you chose your renewable energy source
* Since one term in the competition equation is cost, present the cost of the vehicle. Use the page [[How to Show Cost Data in Presentations]] for instructions on how to do this
* Discuss the power sources and their power output. How did the voltage measurements of the power sources impact the design?
* Discuss your design. Why did you choose the chassis or wheels? How did you factor in the constraints of the vehicle?
* How would the renewable energy vehicle be improved?
* How would the renewable energy vehicle be improved?


Line 392: Line 314:


NextEra Energy Resources, LLC. "Benefits of Renewable Energy." NextEra Energy Resources. NextEra Energy Resources, 2012. Retrieved 24 July 2012. <http://www.nexteraenergyresources.com/content/environment/benefits.shtml>.
NextEra Energy Resources, LLC. "Benefits of Renewable Energy." NextEra Energy Resources. NextEra Energy Resources, 2012. Retrieved 24 July 2012. <http://www.nexteraenergyresources.com/content/environment/benefits.shtml>.
Perlman, Howard.. "Hydroelectric Power: How it Works." U.S. Geological Survey, 2016. Retrieved 4 Jan 2018. <https://water.usgs.gov/edu/hyhowworks.html>.


Reg Tyler, . "Types of Fuel Cells." Energy efficiency and renewable energy. U.S. Department of Energy, 2011. Retrieved 24 July 2012. <http://www1.eere.energy.gov/hydrogenandfuelcells/fuelcells/fc_types.html>.
Reg Tyler, . "Types of Fuel Cells." Energy efficiency and renewable energy. U.S. Department of Energy, 2011. Retrieved 24 July 2012. <http://www1.eere.energy.gov/hydrogenandfuelcells/fuelcells/fc_types.html>.


{{Laboratory Experiments}}
{{Laboratory Experiments}}

Latest revision as of 02:03, 27 January 2024

Objective

The objective of this lab is to evaluate different sources of renewable energy and use the results of that evaluation to design a vehicle that is either directly powered by a renewable energy source or a capacitor that is charged by a renewable energy source. The design will be entered in a competition that is judged by an equation that includes the distance traveled, travel time, and cost.

Overview

From sails to power boats, windmills to pump water, or water-driven wheels to power machinery that mills grains, humans have been using renewable energy sources for millennia. A significant amount of our energy production comes from non-renewable resources, such as oil, natural gas, and coal. The detrimental effects on public health and the environment from burning fossil fuels have prompted greater interest and investment in renewable energy sources, including solar, wind, and hydroelectric power though hydroelectric power is not considered in this lab. Scientists and engineers must address concerns about the inability of some renewable sources, notably solar power and wind power, to generate power consistently so there is equal interest in developing energy storage devices that can operate at grid-scale or hold sufficient energy to power entire communities for an extended time after being charged by a renewable energy source.

Types of Renewable Energy

Renewable energy is a type of energy that can be harnessed from naturally replenished resources. Some examples of renewable energy sources are sunlight, wind, and water. There are many benefits to using renewable energy. If these renewable resources can be harnessed effectively, they can solve the problems with using non-renewable energy sources (NextEra Energy Resources, 2012). In the last few years, renewable energy has been the fastest-growing energy source globally (International Energy Agency, 2021). In this lab, solar and wind energy will be used.

Solar Power

Sunlight, like any other type of electromagnetic radiation, contains energy. Typically, when sunlight hits an object, the energy that it contains is converted into heat. Certain materials can absorb and convert that energy into an electrical current. In this form, sunlight can be used as a power source or stored for later use.

Solar panels are semiconductor-based devices that generate electrical current directly from sunlight. Many high-efficiency solar panels comercially available are made from crystalline silicon (Si).

To produce a current, there must be a difference in the concentration of electrons between one area and another to cause their flow. In a silicon solar cell, a concentration difference is created using two types of silicon, p-type and n-type. The p-type silicon is created by adding atoms, such as boron, that have one fewer electron in their valence energy level than silicon has. As a result, a vacancy of electrons, or a hole, forms. The n-type silicon is created by adding atoms that have one more electron in their valence energy level than silicon has so that there is an excess of electrons that can move around the crystal structure and create an electrical current. In a solar cell, p-type and n-type silicon are sandwiched together to create a p-n junction, as shown in Figure 1 (Locke, 2008). The p-type area is positively charged, and the n-type area is negatively charged.

When sunlight hits the silicon on the solar panel, the photons from the sunlight energize the electrons in the material. The electrons within the crystal move to a higher energy level, creating holes. If the p-type and n-type silicon are connected with a wire, the electrons will flow from the n-type layer to the p-type layer, and electrical current is generated.

Figure 1: A Silicon Solar Panel Showing the Electron Flow

Wind Energy

Wind turbines are used to capture the wind’s energy and convert it into electrical energy. The blades on wind turbines are slanted so that as the wind passes over the blades, it creates an uneven pressure on each side, causing them to rotate. The spinning blades drive a low speed shaft connected to a gearbox. The gearbox converts the low speed rotation to a high speed rotation through a high speed shaft. The high speed shaft is connected to a brake and then into an electrical generator where mechanical energy is converted to electrical energy (Layton, 2011).

A basic electrical generator is made of permanent magnets on each side with a rectangular coil connected to a commutator, which is a rotary electrical switch (Figure 2). The two permanent magnets on each side create a magnetic field. As the rectangular coil spins mechanically, the magnetic field through the area of the coil changes, creating an alternating current through the coil. The commutator switches the polarity of the coil just as the polarity of the alternating current changes, creating a direct current. The current is then output from the wind turbine (Layton, 2011).

Figure 2: The Internal Structure of an Electrical Generator (Layton, 2011)


Energy Storage

Capacitors have many uses in circuits and signal processing. A capacitor is an electrical device that is used to store charge temporarily. In this lab, a capacitor will be used as the power source for the renewable energy vehicle. A capacitor is charged by a voltage source logarithmically, as shown in Figure 3.

Figure 3: Capacitor Charging Curve

Because of their design, capacitors can be sensitive to the polarity of the voltage applied to them. The capacitors used in this lab must be connected with the proper polarity. In this lab, the capacitor’s negative lead must be connected to the negative applied voltage (Figure 4). Failure to do this will cause the capacitor to fail.

Figure 4: Polarized Capacitor

The energy a capacitor holds is proportional to the square of the voltage across the capacitor (1). In (1), E is the energy, C is the capacitance, and V is the voltage.

(1)

Electrical Components

The design of a circuit determines its behavior. In this lab, one circuit design will increase the speed output of a motor and the other will increase the torque output of a motor. In electrical engineering, different electrical components are represented by different symbols. Figures 5 show the symbols for a capacitor, DC source, and battery. They are all forms of energy storage devices.

Figure 5: (left to right) The Symbol for a Capacitor, DC Source, and a Battery

Different arrangements of electrical components allow engineers to design different circuits which can be arranged in two different ways. In a series circuit, the circuit's components are connected end to end (Figure 6). The current in a series circuit remains the same in all the electrical elements.

Figure 6: A Series Circuit

In a series circuit, the sum of the voltages across each element is equal to the voltage of the power source (2). Note that there is a single path for current to flow through. In (2), Vout is the voltage output and VA, VB, and VC represent the voltage of the individual components.

(2)


In a parallel circuit, as shown in Figure 7, the circuit's components are connected at opposing ends. The current that is supplied by the voltage source equals the current that flows through elements D and E.

Figure 7: A Parallel Circuit

The voltage across the elements that are parallel is the same (3). In comparison to a series circuit, a parallel circuit has multiple paths for the current to flow through. In (3), Vout is the voltage output and VD and VE represent the voltage of the individual components.

(3)

For most circuits, they contain both series and parallel components. The parallel components can be thought of as branches, and each branch contains its own series circuit. Figure 8 shows a circuit that contains both series and parallel components. There are two branches, one on the left and the right. The branch on the right contains only series connections, while the branch on the left contains both series and parallel connections.

Figure 8: A Circuit that Contains Components in Parallel and Series

Using knowledge of series and parallel connections, the voltage Vout can be calculated. Since V4 and V5 are in series, the voltage Vout must be equal to V4 + V5 (4).

(4)

Additionally, V1 and V2 are in parallel, meaning that their voltages are the same. Knowing this, and that V3 is in series with the parallel circuit, Vout can be calculated in a different way (5).

(5)

A digital multimeter will be used in this lab to read the current and voltage across components in circuits. Please read the Digital Multimeters Guidelines before performing this lab to understand how to properly operate a digital multimeter. Digital multimeters can measure either voltage or current, indicated by the symbols shown in the circuit diagram (Figure 9).

Figure 9: (l-r) Symbols for a Voltmeter and Ammeter

Depending on whether voltage or current is being measured in a circuit, the multimeter will be arranged in the circuit in a different manner. To measure the voltage across an electrical component, the multimeter must be placed in the circuit in parallel (Figure 10).

Figure 10: Multimeter in Parallel

To measure the current across an electrical component, the multimeter must be placed in the circuit in series with the component (Figure 11). As described in the Digital Multimeters Guidelines, ensure the leads are connected to the correct multimeter ports depending on which value is being measured.

Figure 11: Multimeter in Series

After measuring the voltage and current across a component in a circuit, the electrical power output of that component can be calculated using the Power Law (6). In (6), P is the power (Watts), I is the current (Amperes), and V is the voltage (Volts).

(6)

The motor provided in the lab is a 9 V DC motor that will operate with voltages no more than 9 V with reduced torque and speed (Figure 12). A motor with no load operates under the current of 9 mA, and a stalled motor operates under the current of over 350 mA. Increasing the voltage provided to the motor increases the speed. Increasing the current, increases the torque.

Figure 12: LEGO 9V Motor

To increase the torque or speed of a power source, gear ratios can be used. When connecting two gears with different teeth counts, the rotational speeds of the gears differ. The gear ratio is used to calculate the ratio of rotational speeds of different gears based on the number of teeth of each gear (7).

(7)

Teethout is the gear that is receiving rotational energy and Teethin is the gear that it is controlling. As the gear ratio increases, the output gear spins slower. A gear ratio of 2 means that the input gear must spin two times for the output gear to spin once, a ratio of 3 means the input gear must spin three times, and so on.

Figure 13 shows three gears with different ratios. Taking the red gear to be the input gear, there is a large gear ratio between the red gear and the blue gear it is driving. The blue gear spins much slower, and it transfers that rotation to the yellow gear. Again, there is a large gear ratio between the yellow and green gears, and so the green gear spins even slower.

Figure 13: Gear Ratio Demonstration (Wikipedia Commons)

Design Considerations

  • Which source yields the most voltage per unit cost?
  • Which circuit configuration will provide the most voltage across the load? Parallel or series?
  • Which aspects of the competition formula are most advantageous?

Materials and Equipment

Materials with Price List

Table 1: Materials and Costs
Material Unit Cost Per Unit
Horizon Wind-Turbine 1 $7.50
Solar Panel 1 $10.00
1 F 2.7 V Capacitor 1 $3.00
Alligator Clip Set 1 pair $0.50
LEGO Kit (Limit One Per Design) 1 $0.00
LEGO to Alligator Clip Connector 1 $0.10
Tape 1 foot $0.10

Equipment Used

  • Horizon wind-turbine
  • Sunforce 50013 1 W solar battery charger
  • Adjustable table fan
  • Heat lamp
  • 3 V power supply
  • Digital multimeter
  • Piezo buzzer
  • 9 V DC motor
  • A 1 F 2.7 V capacitor
  • Three alligator clip sets
  • Standard LEGO kit
  • Lego to alligator clip connector
  • Scissors
  • Tape

Procedure

The power storage device and power sources will be tested individually. The results of the tests will be used in determining the best power source for the sustainable energy vehicle.

1. Testing the Power Storage Device

During this part of the procedure, a capacitor will be charged and discharged with a piezo buzzer. The current of the circuit with two capacitors, a piezo buzzer, and a multimeter in series and in parallel will be measured.

Charging a Capacitor

  1. The circuit in Figure 14 will be created to charge a capacitor. Connect an alligator clip to each of the cables coming out of the 3 V power supply. Red is positive and black is negative.
    Figure 14: Circuit to Charge a Capacitor
  2. Connect one of the unconnected alligator clips to one of the leads of the ammeter (the multimeter set to measuring current).
  3. Connect the rest of the unconnected cables (one from the ammeter and one alligator clip) in series to the leads of the capacitor with the polarity indicated.
  4. Charge the capacitor until the current in the circuit is near 0 A.
  5. Discharge the charged capacitor by connecting it to the piezo buzzer. The capacitor is discharging when the piezo buzzer makes a noise.

Power Output of Capacitors in Series and Parallel

  1. Charge a capacitor until fully charged using the battery.
  2. Set the capacitor aside in a safe place. Be careful not to discharge it when moving.
  3. Get a new capacitor and fully charge it.
  4. Wire the two capacitors, the buzzer, and the multimeter in series. Only connect the capacitors long enough to record your measurement. Recharge the capacitors between measurements.
    1. Refer to the schematic in Figure 15.
    2. Remember to check for the proper polarity, otherwise the circuit will not run
Figure 15: Series Capacitors Current Circuit
  1. Record the current produced by the circuit in series.
  2. Record the voltage across the piezo buzzer.
    1. Refer to the schematic in Figure 16.
    2. Remember to check for the proper polarity, otherwise the circuit will not run
    Figure 16: Series Capacitors Voltage Circuit
  1. Repeat steps 1-3.
  2. Wire the two capacitors, the buzzer, and the multimeter in parallel.
    1. Refer to the schematic in Figure 17.
    Figure 17: Parallel Capacitors Circuit
  1. Draw a schematic for a circuit that will measure the current through the piezo buzzer with capacitors in parallel. Get a TA’s approval for the schematic.
  2. Create the circuit and record the current through the buzzer.
  3. Calculate the power output for capacitors connected in series and capacitors connected in parallel.

2. Testing the Power Sources

One type of renewable power source will be assigned and analyzed. Using the digital multimeter, both voltage and current must be measured and recorded, and the power output must be calculated.

Wind Turbine

  1. Connect the wind turbine to the piezo buzzer using the alligator clips following the schematic presented earlier. Measure the voltage and current across the piezo buzzer using the digital multimeter.
  2. Adjust the position of the turbine blades near the fan to find the highest voltage and current that can be generated.
  3. Calculate and record the power generated by the turbine and give the information to a TA (Figures 18-19).
Figure 18: Circuit to Measure Voltage of the Wind Turbine
Figure 19: Circuit to Measure Current of the Wind Turbine

Solar Panel

  1. Connect the solar panel to the piezo buzzer using the alligator clips. Place the solar panel near the heat lamp and measure the voltage and current across the music voltmeter using the digital multimeter.
  2. Adjust the position of the solar panel to find the highest voltage and current that can be generated.
  3. Calculate and record the power generated by the solar panel and give the information to a TA (Figure 20).
Figure 20: Circuit to Measure Voltage of the Solar Panel
Figure 21: Circuit to Measure Current of the Solar Panel

Data Analysis

  1. The TA will display the power data from each renewable energy source on the board. Based on the power output of each renewable energy source and the analysis of the circuits in series and parallel, determine the best power source and circuit design to power a sustainable energy vehicle with two capacitors.

Caution! The heat lamps and solar panels may become extremely hot when used for a long duration of time. Do not touch them immediately after use and turn them off when not in use.

Competition Rules

The competition rules must be followed at all times during the competition. Violation of any of these rules will result in the disqualification of the design.

  • The renewable energy vehicle must carry its power storage device (e.g. capacitor)
  • The capacitors may only be connected to the power source for one minute regardless of how they are connected.
    • If two capacitors are connected and charged in series, they may only charge for one minute.
    • If two capacitors are charged in parallel, they may only charge for one minute.
  • Each design will only be allowed one trial.
  • Do not touch the leads of the charged capacitors or allow the leads to touch each other, this will discharge the capacitor.
  • Do not connect the power storage device until immediately before the trial is run.
  • The trial will end once the vehicle stops moving or after a maximum of 5 min.
  • The design with the highest competition equation (CE) result wins (8). In (8), distance, time, and cost are measured in feet, seconds, and US dollars respectively.

(8)

3. Sustainable Energy Vehicle Competition

  1. Assess the materials provided and consider the data from testing the power storage device and testing the power sources. Keep in mind the variables of the competition equation while choosing materials for the vehicle design. Make preliminary sketches during this process.
  2. A minimum of two capacitors must be used in the design. The vehicle must carry the power storage device during the trial. While modifying the design, keep in mind the space needed to fit the power storage device (capacitor) and its wires. Prepare a cost list of the materials used in the design and specify the total price. A TA must approve the sketches and the cost list.
  3. Create a circuit diagram on paper containing the capacitors and motor. The diagram should reflect how the vehicle is wired, and should be used when constructing the vehicle. A TA must approve the your circuit diagram.
  4. A TA will provide the materials needed for the design. If the design is modified during the construction, note the changes and explain the reasons for them. If the modifications require more materials to be used, update the cost list and have a TA approve it.
  5. With the chosen power source, charge the capacitors for 1 min.
  6. Construct the vehicle based on the sketched design.
  7. Before entering the competition, make sure the motors turn in the desired direction of travel.
  8. Run the trial.
  9. Give the total cost of the design to a TA. The TA will provide the competition equation result.

Assignment

Team Lab Report

Follow the lab report guidelines laid out in the EG1004 Writing Style Guide in the Technical Writing section of the manual. Use the outline below to write this report.

  • Describe the rules, competition equation, and design strategy of the competition in the introduction. What consequences did the rules and competition equation have for any design decisions?
  • Explain how solar panels and wind turbines work
  • Discuss capacitors
  • Discuss the advantages and disadvantages of the solar panel and wind turbine
  • Describe the renewable energy vehicle design and explain the choices made in the design
  • Discuss the power sources and their power output. How did the voltage measurements of the power sources impact the design?
  • Discuss minimal design. Were all the materials purchased used? Describe the importance of minimal design and explain how it was employed in the design. Did the design minimize cost?
  • Describe how the design succeeded or failed. What choices would improve the design’s standing in the competition?
  • Discuss how the competition equation can be increased, and how the design compared to the other designs
  • Specify the power source chosen for the design
  • Include the spreadsheet with every design's results. Describe the results and talk about other designs in the competition
  • Include a digital drawing of the motor circuit used in the sustainable vehicle design

Remember: Lab notes must be taken. Experimental details are easily forgotten unless written down. EG1004 Lab Notes paper can be downloaded and printed from the EG1004 Website. Use the lab notes to write the Procedure section of the lab report. At the end of each lab, a TA will scan the lab notes and upload them to the Lab Documents section of the EG1004 Website. One point of extra credit is awarded if the lab notes are attached at the end of the lab report. Keeping careful notes is an essential component of all scientific practice.

Team PowerPoint Presentation

Follow the presentation guidelines laid out in the EG1004 Lab Presentation Format in the Technical Presentations section of the manual. When preparing the presentation, consider the following points.

  • Since one term in the competition equation is cost, present the cost of the vehicle. Use the page How to Show Cost Data in Presentations for instructions on how to do this
  • How would the renewable energy vehicle be improved?

References

Layton, J.. "How Wind Power Works." How stuff works. Discovery, 2011. Retrieved 24 July 2012. <http://science.howstuffworks.com/environmental/green-science/wind-power.htm>.

Locke, S.. "How Does Solar Power Work." Scientific American. Scientific American, 2008. Retrieved 24 July 2012. <http://www.scientificamerican.com/article.cfm?id=how-does-solar-power-work>.

NextEra Energy Resources, LLC. "Benefits of Renewable Energy." NextEra Energy Resources. NextEra Energy Resources, 2012. Retrieved 24 July 2012. <http://www.nexteraenergyresources.com/content/environment/benefits.shtml>.

Reg Tyler, . "Types of Fuel Cells." Energy efficiency and renewable energy. U.S. Department of Energy, 2011. Retrieved 24 July 2012. <http://www1.eere.energy.gov/hydrogenandfuelcells/fuelcells/fc_types.html>.