I started biochar project at 2014 April, in summer. I could do nothing about this project at 2015. This yeair I m going to do again. I will do every summer of my country. This biochar used raw materials from agriculture wastes such as dry leaves. dry plants etc. My intention is for environmental protection. Most of the people here cut down the trees and making charcoal so deforestation is occurred. I want to substitute this charcoal with biochar. So I am trying my best.
Here is my first attempt to solar cookers. It was not good due to the cold weather. I live in the cold weather. So my first attempt to solar cookers failed. But it is useful for solar drying system. I am going to test another solar projects. It reached to 70 Degree centigrade, I think it is not enough to cook. But I am trying my best as much as I can.
tHere is my first solar cell. Output power is about 27.3 mW for open circuit. The output voltage is 170mV and the output current is about 160mA under the good sunlight. It is based on the electro-chemistry. Even it works properly, I could not do well the cuprous oxide. I'm going to do it again.
Do It Yourself?
Right! you can do easily at your home. This is my first attempt to solar cell. I want to show my procedure. Check it.
(1) A large Copper sheet and one 2Litre bottle we need.
(2) Cut to 2 sheets. I have done with 20cmx 9cm. (3) Heat one sheet for a long time. In my project. I made it with gas stove for half an hour. I did not get cuprous oxide so much. It may be decrease the proficiency of solar cell.
(4)Don't heat another sheet. Put these 2 sheets together in the bottle. Pour the salt-water slowly.
We must cut the neck of the bottle before putting materials together. And we can use easily. It's not so good. But It might be good for photo-detecting. See my pictures.
These above photos show current measure in mA scale under sunlight and shadow.
Here is my new solar cooker, created in on August 2012. It's rainy season now. So I can't test now.
Ok, Please look at these photos and diagrams, hot do I make a solar power lamp easily. First I buy China made electric lamp and it cost about 1.2$
The solar cell cost about 9.5$. I show the characteristics above. It's the back of solar cell.
The battery is from the damaged MP3 Player. It's capacity is 550mAh and output is about 3.7V.
Open the nuts from the body cover and remove the batteries from the battery chamber.
connect the wires properly and put the Li-ion rechargable battery in the battery chamber.
make a hole to take out of the wire, fix up the nuts with body and cover the lid.
Now it's ready to use and the right photo is charging under the sunlight.
Wow! It's really good. It's easy to make it and by using the re-chargeable battery, you can save the world.
Here is the solar power mobile phone charger with circuit diagram. The solar panel gives 20V for open loop circuit (VOC) and about 4A for short circuit current (Isc). The panel output was controlled by regulator circuit. Regulator circuit gives 5V. Maximum output power is 20W. The output power is connected to USB hub to charge 4 mobile phones at the same time. The regulator circuit use LM323 and 7805 connected by parallel to get good current outcome. I used the polycrystalline solar panel. It is less efficiency than mono-crystalline solar panel. But the result is really good.
This photo shows testing the effective solar power mobile phone charger
This figure shows the complete circuit symbol for charger
In this constructed solar power bank, maximum input power is 3W and the power bank storage is 4000mAh. The surface area of solar panel is about 19cm x 15cm = 0.028m2, which is not so good for charging but that small portable size is good for travelling. By experimental results, the solar power bank needs 5hour bright sunlight continuously. In this project, regulator IC should be used to get the stable voltage for the battery bank. This project does not use regulator IC 7805 since the full charge voltage is about 5.6V. Instead, it can be used 7809 regulator IC. Most of the mobile phones and tablet use approximately 3.7V. This solar power bank is good for the charging system. The solar power bank of this project is convenient for using outdoor when there is a lack of electricity. The disadvantages of this solar power bank is charging time. It will be time consuming for full charge. Further efficient solar power projects will be done in future. Solar power banks are an invaluable investment for anyone who spends lots of time away from electricity while still needing plenty of electronic devices.
Complete circuit diagram
Perspective view of power bank