“Hi, how are you? I’m glad that you are interested in what I am doing or just BlueStamp Engineering. If you are interested in BlueStamp Engineering, just simply click HERE. However, I strongly recommend you to view my webpage because I am sure you will be amazed by my web design and you will learn a lot from it. I made a parking sensor for my starter project, and I made a generator powered by fire for my main project. The generator was designed from ground up by me. I changed my design three times. I ended up with an amazing project. You definitely won’t be disappointed when you see it.”
Picture of my project
- Table of Contents
This site contains a lot of information. Choose the information you want to know.
- Self Introduction
- Main project
- How to measure the I-V curve
- Get the I-V curve
- Compare water cooling and air cooling
- Electronics Generator Structure
- 3D design
- Warnings and tips
- Bill of materials
- Starter Project
- contact information
You probably already know my name,but I still want to mention it again so that you can remember my name better in the future. My name is Simon. I am going to be a freshman at Westbury Christian School. My dream is to go to Silicon Valley and start my own business. If you asked me what I like, challenges would be the word I answer. I like to have a goal that I have to work really hard to achieve. I enjoy solving a problem much more than the reward after. Reality never has reached my expectations.
Main Project Idea
For my main project, I chose to make a generator that runs on heat. You must be thinking that I am going to heat up the water and use the steam to turn the turbine. Then, I will use the turbine to generate electricity. These kinds of generators are complicated and not convenient. In order to make a portable and simple generator, I need to use Seebeck effect. The Seebeck Effect was discovered by a Thomas Johann Seebeck in 1821 saying some kind of metal can become negatively or positively charged when there is a temperature difference in one piece of metal. He put two kinds of metal side by side and he made a temperature differential in each metal. He heated one side of the metal and cooled down the opposite side. He found out that there is a relationship between temperature difference and magnetic field. Later, a scientist found out that the magnetic field is produced by the flow of electrons. From then on, the TEG module is invented.
A TEG module uses the temperature difference to generate electricity. It is not being used for electric generating because the module doesn’t absorb the heat or it is using the flow of heat instead of heat itself. Basically, you can boil the same amount of water with the same amount whether the module is there or not. the difference is that the heat takes longer to go through the module than normal metal.
Of course, the TEG module is the main component for my project. TEG stands for Thermal Electric Generator. Normally, the hot side of the TEG module can only stand up to 175 degree Celsius. The cold side, however, can only stand up to 60 degree Celsius. When the temperature gets too high or the temperature difference is too big, the strong current in the module will fry the semiconductor inside and stop generating current. It is unnoticeable on the outside of the module and people have to compare against the IV curve provided by the factory. The module I used is a high temperature module. It is reinvented base on the modern technology. It came up just a couple of years ago. Not only the hot side can stand up to 300 degree Celsius instead of 175, but also the cold side can stand up to 160 degree Celsius instead of 60. Although it can stand high temperature, it is still very sensitive. Large temperature difference or too high temperature will still destroy the module. In order to make the heat flow through the module, to make the hot side as hot as possible is not a solution because when the module gets hot, the heat is not moving in the module. It is stored in the module. Like electrons stored in the battery, the electrons in the battery are not powering up anything. In order to let electrons flow we have to have a negative side to suck he electrons from the positive side. Same thing with heat, the heat cannot move unless you provide a cold side to suck the heat in. Imagine when you heat up a bottle of water, the water is heated up by the burner. Basically, the heat went through the container and heated up the water. In order to make the heat go through the module, I can heat up the module on one side and get something cold on the other side. In this way, the module will work, but only for a minute. In this case, I have to keep the hot side hot all the time and cold side cold all the time. In this way, the heat will flow continuously, which means the module will generate electricity continuously. After understanding how the module works, I have to start designing and making the system. First things first, I have to make sure the module is working properly. If the module is not working properly, nothing will be generated. I have to test the module and compare the data I get against the data provided by the factory. I decided to get the I-V curve of the module and compare the I-V curve with the I-V curve provided by the factory. The I-V curve explains the relationship between the electric current through a circuit, device, or material, and the corresponding voltage, or potential difference across it. Basically, an I-V curve can help people determine if a electrical device is working properly and it also shows the characteristics of the device.
How to measure the I-V curve
After knowing the I-V curve of different electronics, another problem comes up. How to measure the I-V curve? I-V curve is the relationship between open circuit voltage and short circuit current. When I get the module this is the first thing. It is time to start designing the generator. I think I am able to use 5 modules to make a huge generator and I started thinking to use water cooling as a cooling method. Bluestamp Engineering sent me a Excel called BlueStamp Engineering Student Bill of Materials(BOM). I designed the generator on the paper at home. I listed what I need on the BOM. Later, however, I changed all the design and I got a all new BOM after the program.
Get the I-V curve
After three days, after I receive what I need. I am able to get the I-V curve of my project. In order to get the I-V curve of the TEG module, I have to have at least three points on the chart and graph the I-V curve. I set the temperature of the hot plate to medium and I used a big fan with a big heat sink, plus a paper board in between as a insulator. The fan is powered separately by another power supply. I didn’t record the temperature because I-V curve only explains the relationship between short circuit current and open circuit voltage. It doesn’t have anything to do with temperature, but the temperature difference.
In my opinion, when the temperature difference is the same, the power generated by the module should be the same.
When the voltage was stable, I measured the temperature. The hot side temperature was 167 degree celsius and the cold side temperature is 61 degree celsius when I started. I recorded the open circuit voltage. And short circuit current. I then put five different loads and recorded five times and I got different voltages.
The load I used was power resisters. In this way I am able to ge the I-V curve. The reason why I use power resisters is that they can stand high current. Normal resisters can only stand 1/4Watts, however, power resisters can stand at lease 2Watts.
Here is the I-V curve I got when the temperature difference is 100 degree Celsius:Here is the I-V curve I got. I am not able to make the cold side down to 30 degree Celsius when the hot side is 300. What I could do was that I can create a 100-degree difference. The hot side was 167 degree Celsius and the cold side was 61 degree Celsius.
The next thing is to compare my I-V curve to the I-V curve provided by the factory. I found the data sheet on “THIS WEBSITE“. I found the I-V curve provided by the factory.Here is the data sheet provided by the factory. The factory tested the module when the hot side is 300 degree Celcius and the Cold side is 30 degree Celsius. they are trying to show the best side of their module to people.
Compare water cooling and air cooling
In my opinion, water cooling systems are widely used in cars or super computers. Air cooling systems, however, are widely used in normal computers. During the research, I found out that people using water cooling system for their computer is because they look good and more complicated. Water cooling can definitely make their computer look modern and hi-tech. Cars, however, use water as a carrier for heat. In this way, engineers don’t have to put the radiator on the cylinder like motor cycle and they will be able to put cylinders together to save room. In this case, I think water cooling is better. I don’t have to put the heat sink on top of the module and I can use a big radiator and a big fan to cool down the water. Air cooling, however, is much more simple and easy to fix, however, the heat sink could be heated up by the fire not the module.
I used paper board as a insulator for my heat sink to make sure that the radiator is only getting the heat from the module, not the hot plate. When the temperature of the hot plate is 180 degree Celsius, fan-cooling can decrease the temperature of the cold side to 80 degree Celsius. When the temperature on the hot side is 295, fan-cooling can reduce the temperature of the cold side to 125C.
I used a piece of soaked up napkin on top of the module and a fan to make water evaporate faster. when the temperature on the hot side is 180 degree Celsius, water-cooling can reduce the temperature to 75C. When the temperature on the hot side is 295, water-cooling can reduce the temperature of cold side to 100C.
|Water cooling||Fan cooling|
I got a voltage difference of 0.28V and a current difference of 17mA at 180 degree Celsius. I also got a voltage difference of 0.48V and current difference of 25mA at 295 degree Celsius. I raised the temperature above 300C. I found out that the current starts acting unstable although the voltage reached 5V. I also can hear some cracking noise from the module. I removed the heat source immediately and I found out that the module had broken. I cannot tell by just looking at the module. However, when I heated up that module again, the output current and voltage had reduced a big amount. During this experiment. I found out that water cooling is better than air cooling. The purpose of this generator, however, changed my opinion. Air-cooling is so simple and reliable compare to water cooling. I don’t have to put water in the system all the time. I am able to use the generator with air cooling right way. It can sit somewhere for years without refiling l water or clean the reservoir and the tubings. I also don’t have to dump the water out after using. As a result, air- cooling is a better way to cool although the efficiency is lower than water-cooling. Its reliability and simple construction amazed me.
Before designing the generator, I decided to design my circuit. It seems easier to design, compared to the structure of the generator. I ordered a buck-boost and it didn’t work for some reason. The voltage NEVER got above 0.5V and there is nearly NO current after the buck-boost. I remembered that the voltage never went more than 5V when I tested the module. I decided that it is better to use a boost only for my generator. The voltage could go too high, which is more than 5V. However, it is not very unusual. I am planning to add a voltage monitor to my generator for my modification. I tried to charge my phone with the normal USB circuit. Unfortunately, I fried my iPhone charger. The problem was that the voltage coming out of the data plus and data minus are way too high. there were 3V coming out of data plus and 3V coming out of the data minus. The right voltage for iPhone is 2.76V for data minus and 2.06 for data plus. 1V higher can make a big difference. I got a new one for free luckily because it was under warranty. I found the problem and I changed the circuit. It worked for my iPhone finally.
Here is my schematics
After finishing design the structure of the generator, I put the circuit on the generator, I found out that the circuit sometimes can not start unless there is a battery. On this generator, the boost has to receive a voltage that higher than 3V in order to work. a lot of heat has to go through the module in order to make the voltage reach 3V. The heat sink is heat up and the module doesn’t generate enough power for boost to work. Normally, before the heat sink is heated up, the boost started working and the fan started turning. As the fan started turned, the heat sink is cooled down. It provides a bigger temperature difference on the module and the module starts to generate more electricity and the system started. In low temperature, things become different. No matter how long I wait, the fan doesn’t want to turn on. The problem is that the module takes longer to raise the voltage to 3V. When the voltage from module is about 2.5V. The voltage started to decline. The heat sink has been heated up and the temperature difference begin to decline, which mean the fan will never get to work. To increase the temperature difference, I ended up using a battery to reduce the temperature of the heat sink. When the temperature of the heat sink is reduced, the voltage went up and the boost starts. The whole system then is started. I can just go ahead and turn the switch to the off position. I call the battery “APU”. APU stands for auxiliary power unit. A lot of teachers and classmates said to me that they didn’t see a battery on my schematics. The battery symbol is very small in my schematics. which is G1.
Then, it’s time for my construction. I spent more than two week on this part. I built three generations. I started building the generator even before switching the water cooling method from water to air. That is my first generation.
The first generation
I only used 3 days to finish the first generation. It was designed from ground up and it was based on what I had. You will probably understand how it worked on the video below: I found a lot of problems on the first one including water seal, reliability, water going into the module, plastic melting and so on.
The second generation
Problems with the first generation
- Water cooling is not reliable enough
- Base plate is not one piece. As a result, the generator is not strong enough.
- generator has to be vertical position or water will come out
Form then on, I started my second generation generator. I changed my cooling method from water-cooling to air-cooling. I this way, I increased the reliability and the generator doesn’t have to be vertical position. I ordered a 10″x10″x0.2″ aluminum plate and cut it into the detention I needed for my base place. I ordered a different heat sink.
This heat sink is so big and efficient that it only needs a little amount of air to be cooled down. In this case, I used a small fan, which only requires 0.2A to work. Thinking the module may not be able to charge my phone. This fan, however, can only cool the cold side about 20 degree Celsius down and make a 20 degree Celsius difference, which is not enough temperature difference for the module to generate electricity and charge my phone. The second problem was that the fan is too small for my big heat sink. It cannot decrease the temperature of the heat sink efficiently. As a result, the heat sink stays inefficient. I also didn’t know that both of the modules were not working. The low current fooled me. I waste 1 week trying to find the problem, which was inside the module. Another thing is that the thermometer of the Mutimeter doesn’t display the right temperature of the hot plate. When the temperature goes higher, the multimeter displayed temperature is about 30 degree Celsius lower than the normal temperature. When the multimeter display 300 degree Celsius, it is actually 330 degree Celsius. As a result, the module brake unnoticeably. fan can only cool the cold side about 20 degree Celsius down and make a 20 degree Celsius difference, which is not enough temperature difference for the module to generate electricity and charge my phone. This fan does’t need a lot of electricity to work, however, the fan is not efficient. there is not a lot of wind coming out of the fan because the fan is too small. I calculated the efficiency by putting two small fans together and compare the wind speed to a 0.25A big fan. The big fan works better than two small fans on cooling the heat sink.
The third generation
Problems with the second generation
- I the heat sink is connect to the base place by 4 machine screw, the heat can go through the machine screw and heat up the heat sink.
- The fan is terribly inefficient.
- The paper board insulator is easy to catch on fire.
For my 3rd generation, I need to get a efficient fan. Insulator catch on fire is not a good thing. I have to have a better insulator. I also need to find a way to put my heat sink on the module and prevent the heat to go through the screw. The screw not only can heat up the heat sink but also it can cool down the hot side. Also, I stated the to design more detailed. instead of the whole generator, I changed my perspective to every single part. I looked at every parts closely and tried to make them better. Every part is designed separately acrroding to the 2nd generation. I solved the safety issue by changing the paper broad to aero blanket. The fan is much bigger compare to the one before. The method of putting the module on is special designed. I also changed the connecting method. I made the third generation upgradeable. People can easily upgrade the electronics by changing the board.
3D design for my third generation
Base place + insulator
base plate + insulator + module
base plate + insulator + module + heat sink + legs
Warnings and tips
- The module is very sensitive to the temperature. Make sure that the hot side temperature is lower than 300 degree Celsius and the cold side’s temperature is lower than 160 degree Celsius if you are using the high temperature module. Temperature should be in the temperature range provided by the factory.
- The insulation is very important. The heat can easily go through the air and heat up the heat sink. Paper board is not capable on high temperature. It will catch on fire when the temperature is too high.
- Phone chargers are very sensitive. Make sure all the specifications meet your Phone specifications. too high voltage will fry the charger and your phone.
- Check the module condition frequently. Change the module when the data doesn’t meet the data provided by the factory.
- Bolt the heat sink tightly on the module’s cold side for better cooling performance.
- Never think the fan is too heavy to power up. The output current should be plenty for the fan.
- Find a fan that it can cover the whole heat sink.
- A big heat sink and a big fan work better than a small heat sink and a small fan.
- Although the bigger fan is better, make sure it doesn’t draw too much current. I recommend no more than 5v 0.3A.
- Bigger module is better because there is more surface area than small one. It can really help to transfer the heat to the heat sink.
- The voltage of the module may change although the temperature and the temperature difference stays the same.
- Getting more voltage doesn’t mean getting more current.
- Make sure you get the right-sized aluminum plate. Sawing aluminum will waste a lot of time.
- Make sure to put enough thermal paste on the cold side to help heat transfer.
- No thermal paste on the hot side, it will burn.
- Always put an auxiliary power unit (APU) in case the module lose power.
- Make sure you have a place to put the electronics.
- Double check the generator before putting it on the fire.
- Although water cooling is more efficient, don’t forget to consider the complicatedness of water cooling.
- Pay attention to every detail!
Bill of materials
I had three BOMs and here is My final BOM. It is the most perfected and the most simple BOM. With this bill of materials, you will be able to make them like mine.
For my modification, I want to add a temperature monitor and voltage limiter. I want to learn some programing by programing the Arduino board. My goal is to connect a LCD screen to the Arduino and the screen not only can tell me the temperature and the voltage, but also can warn me in a good time if the temperature and the voltage went too high or not.
I have to program the Arduino board. Here is the code: the code for my temperature and voltage monitor
Sai tough me how to use function in c-programming. With the help of Sai, I am able to write the code by myself and to get the code done in two days.
The monitor now can tell me the temperature and the voltage of my generator. They will both be displayed on the LCD screen. I rewrote the coding three times due to forget to save.
I learnt a lot in this program. This problem really opened my eye. It trained my ability to communicate with all kinds of people. It also provided me a chance to have more friends. During this program, I see people struggling so hard to get their project done. People enjoy doing their project that they never take a brake for 4 hours. I can hear teacher encourage their student when they cannot get over their milestone. I experienced that teachers only show me what I should do instead of doing everything for me. They always make sure that people are learning to solve the problem themselves instead of asking for help. When we have the ability to solve the problem and document the project, we can hopefully go faster and further than anybody else.
If you have any question about my project or any comment about me, simple tell me through my E-mail. E-mail: [email protected]
I chose to make a parking sensor for my starter project because It has a lot of electric components including resistor, transistor, diode, buzzer, IC and so on. Like what I said, I like challenges and I really enjoy figuring out complicated things because I can always learn a lot from it. I did a lot of research before making this project. This sensor uses ultrasonic wave to measure the distance. The transmitter in the sensor generates high frequency sound waves and evaluates the echo which is received back by the receiver next to the transmitter. The ICs in the sensor calculate the time interval between sending the signal and receiving the echo to determine the distance to an object.