Parabolic solar collectors are composed of curved, mirror-lined troughs or dishes designed to collect and concentrate sunlight. Unlike parabolic dishes, parabolic troughs are linear concentrated solar power collectors. They are aligned north to south. Sophisticated systems employ solar tracking devices that allow the mirrors to move with the sun's path. The mirrors direct the light to a focal point that causes the light to become concentrated. This concentration of heat is capable of boiling water and creating steam, which can power generators and provide electricity. A miniature version of a parabolic trough solar collector may not power your television but can provide a better understanding of the principles behind concentrated solar power.
Things You'll Need
- Phone book
- One book (thinner than a phone book)
- Cardboard tube
- Brass brad fasteners
- Aluminum foil
- Black aquarium tubing
- Shallow dish
- Styrofoam cup
- Plumber's putty
- 100-200 watt light source or direct sunlight
Arrange a phone book and a thinner book than the phone book on a table like steps. The table acts as the first step. The thin book is the second step. The phone book is the top step.
Slice a cardboard tube in half lengthwise.
Place the cut halves back to back. One side will become the parabolic base and the other the parabolic collector.
Fasten the halves together with brad clips. Point the brad clip prongs straight up on the collector side of the tube.
Attach aluminum foil (shiny side up) to the collector side of the apparatus using adhesive. Slit the aluminum foil to allow the brad prongs to pass through.
Adjust the prongs to form a loop. The base of the loop should not touch the aluminum foil.
Thread black aquarium tubing through the loops, leaving equal amounts of excess tubing on each side of the cardboard collector. Place the collector on the middle step.
Place a shallow dish on the table. Place one end of the tubing into the dish.
Poke a hole in the side of a Styrofoam cup, near the bottom. The diameter of the hole should be equivalent to the diameter of the tube.
Place the Styrofoam cup on the phone book, or top step.
Insert the tubing into the cup's hole. Use plumber's putty to ensure a tight seal.
Shine a 100-200 watt light source or allow the sun to heat the aluminum foil.
Pour water into the Styrofoam cup. The water will run downhill through the tube and into the shallow bowl. The parabolic solar collector will heat the water as it passes through the tube. The result: The water in the shallow bowl will be warmer than the water in the cup.
Types of Solar Concentrators
Solar concentrators are large-scale devices in solar thermal systems. The concentrators use mirrors and lenses strategically arranged to maximize the use of...