View Cart

Tracking the Sun

by Lincoln Kraeuter
(Jensen Beach, FL, USA)

This blog will describe a solar tracking mechanism which can be used for large paraboloids or conical horns. The chefs of India requested a solar oven which delivers 1000 watts. What is the diameter of a paraboloid which delivers 1000 watts? 1000 watts = 1100 watts/ square meter x .75 x area in square meters where .75 is the reflection efficiency of aluminum foil. Then using the equation: area = pi x radius squared yields: 1.212/ pi = radius squared = .386 taking the square root gives: .621 or a diameter of 1.24 meters. This is a fairly large paraboloid and rather awkward to adjust to the transiting sun. A system of pipes and bearings would help. There are three requirements which must be satisfied to track the energy of the sun. DAILY AXIS of ROTATION First: the paraboloid must rotate on an axis that parallels the axis of the rotating earth. That is, an axis that points to the north star and the southern cross. One can use a magnetic compass to approximate the north south line on the surface of the earth. But, when you see the north star it is not on the surface of the earth. It is at an angle above the surface. This angle is equal to the latitude of the stove/oven site. For example: the island of Hispaniola is roughly at 20 degrees N Lat. Therefore,the north south axis is pointed 20 degrees upward to the north star. South Sudan is roughly 8 degrees N Lat. Tilt the daily axis 8 degrees upward to the north star. Second: The seasonal change in the transit of the sun is caused by the tilt of the earth's axis to the orbit around the sun. The earth's axis still points to the north star. An imaginary line drawn from the center of the sun to the center of the earth traces out lines of latitude, approximately. As the seasons change from winter to summer, this line shifts from the tropic of Capricorn, 23.45 S Lat. through the equator, and then to the tropic of cancer 23.45 N Lat. As seen from the earth, the noon day angle of the sun changes 23.45 plus 23.45 equals 46.90 degrees. This change is in south to north direction, taking one half a year. It then cycles back 46.90 degrees to winter. The paraboloid horn must be tilted 46.9 degrees in a north south direction to maintain a stationary focus. This is done by drilling eight or more bearing holes in the beams supporting the solar collector. when the focus moves approximately 7 degrees north or south the bearings must be reset. Continued under the title: Tracking the Sun



__________________________________________


Thank you Lincoln for your hard work and effort to help us understand how an efficient tracking system can work.
I am sure there are those who visit this site that will find this helpful.

Thanks again.

Nathan
Admin.

Comments for Tracking the Sun

Average Rating starstarstarstarstar

Click here to add your own comments

Rating
starstarstarstarstar
Himin Solar Cooker
by: Lincoln Kraeuter

An answer to your question: How do you clean the tube of the Himin Solar Cooker? I think the tube will become carbonized on the inner surface of the tube. This will block radiation from reaching the food being cooked. However the carbon interior surface will become very hot, and the air within the tube will convect the heat to the food. The carbon coating may be washed with a soap or detergent, and then burned with solar energy. Carbon will oxidize to for CO2. Search for Himin Solar cooker on Google. It is manufactured in China.

P.S. The Himin Solar Cooker uses a trough collector. Find my blog on trough collectors. They can be constructed to concentrate considerable solar energy. Lincoln Kraeuter

Rating
starstarstarstarstar
Himin Solar cooker
by: Anonymous

How does one clean the solar tube of the Himin solar tube cookers?

Click here to add your own comments

Join in and write your own page! It's easy to do. How? Simply click here to return to Already built your own home made Solar Oven? Share your experiences with us..


Enjoy this page? Please share it with others. Here's how...

Would you prefer to share this page with others by linking to it?

  1. Click on the HTML link code below.
  2. Copy and paste it, adding a note of your own, into your blog, a Web page, forums, a blog comment, your Facebook account, or anywhere that someone would find this page valuable.

SOLAR COOKER CATEGORIES

Panel Cookers

   All Season Cooker 

   Sunflair Cooker

Box Cookers

   All American Cooker

Parabolic Cooker

   Solar Burner

Evacuated Cookers

   GoSun Stove

   GoSun Go

Accessories

   Protective Covers

 Discontinued Cookers


New Financing Options available for purchase of Solar Cookers


Email Newsletter icon, E-mail Newsletter icon, Email List icon, E-mail List icon Sign up for our Email Newsletter
For Email Marketing you can trust