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How to harness Sun's energy by making a solar concentrator
A solar reflector can be made very easily. The beauty of a parabolic reflector is that you can concentrate parallel rays of sun on a particular point. It can be used for various purposes. It has applications in solar cooking, pasteurization and even in air-conditioning(No, this is not a typo). The design I am presenting is very cost-effective. Aluminium is chosen as the reflective surface. The reason for not choosing mirrors is that they are very fragile and can cause injury to its handlers. They are expensive also. While Aluminium sheets are cheap and light weight. As far as reflectance is concerned Aluminium's reflectance is second to glass mirrors only. So you should not worry about reflectance.
You need following things for your reflector:
- a fiber glass dish antenna
- Aluminium sheet
- A pair of scissors or a sharp knife
Step 1 Buy a parabolic dish antenna.
Visit any shop which is selling fiber glass dish antenna. Ask him to give you a 6ft diameter dish (or of any size you wish). Don't buy the transponder because you are not going to use this antenna for watching television channels. This would reduce the price. You can also visit a nearby junkyard to buy an old dish antenna, since it would cost much lesser. Make sure that the dish antenna which you are buying is made of fiber glass because this material is light-weight and easy-to-handle. This dish antenna would cost you around $12.
Step 2 Do some calculations
You have to perform some calculations now.
Measure the diameter of the parabolic dish(Do it even if the shopkeeper told you the diameter. You should have exact value of diameter.)
Calculate the circumference by using the following formula:
circumference = 3.14*(diameter of the dish antenna)
Although this formula is for circle we can use it for a parabolic dish as well to make our calculations fast and easy.
The value of circumference which you are going to get from the above formula will be equal to the length of the sheet that is required.
Find the radius just by dividing diameter by 2. (radius=diameter/2)
Remember, you have to buy the sheet whose width is a bit larger than the radius of the parabolic dish.
You have now calculated two values:
1. required length of the sheet
2. required width of the sheet
Step 3 Buy aluminium sheet and glue
Buy aluminium sheet and glue from a hardware store. Aluminium sheets are usually available in the form of rolls. Whenever somebody goes to buy some sheet, shopkeeper just asks the required length. You have to take care ofthe width also. Ask him the width. Do not buy the sheet having width smaller than the "required width".Choose a glue that can stick to any surface. Ask the shopkeeper if you have any difficulty in choosing the right glue.
Step 4 Cut the aluminium sheets
Now we have to cut the sheet into several triangular pieces. For that, you have to divide your sheet into six to eight equal parts. Divide the required length by 6 or 8. Mark points at equal intervals (the calculated value)
Cut the sheets perpendicularly to get rectangular shapes
When you are done with pasting these triangles all along the circumference, leave the glue to dry.
After a few hours your reflector is ready to bedazzle anyone(or anything)!
Support 'mechanism' for hanging pot and keeping it at the focus
To make the supporting mechanism you will need:
- Antenna pole
- Some steel wire
- Empty used paint bucket
- Nut and bolt
Things you will need
Choose a pole that has several through holes in it. Make some concrete slurry and pour it in the paint bucket. Now insert the pole vertically into the slurry. Let it dry.
When the concrete solidifies, bolt the strut to the pole. Strut should have holes at both ends.
Use one hole to bolt it to pole and the other to hang wire.
Adjust the location of the pot by loosening and tightening the bolt.
Pot can be hanged using the steel wire, as shown below.
Please note that this solar parabolic cooker can be used as a hot dog solar cooker. Make sure that while implementing this solar cooker project you do not touch the hot solar cooker as it can cause your skin to burn.