The Haines Solar Cooker combines the power of a Funnel cooker with stability of the traditional CooKit. It has been designed by Roger Haines of San Diego, California, USA. The cooker is made in the USA from a mylar-coated reflective bubble insulation material that is sold "off-the shelf" at Lowe's Home Centers in 4-foot by 25-foot rolls. The material can also be ordered on-line in the US under different brand names, and is also available in Europe, India and China. The material is strong (Roger has driven his car over it without breaking the bubbles) and it is unaffected by boiling water. The cooker is made from a single 48" by 48" rectangle of bubble material, and requires only three cuts with ordinary scissors for cooker assembly. In testing in San Diego, this cooker heated an empty pot to a sustained 380 degrees Fahrenheit (193 degrees Celsius) and heated a liter of water from room temperature to boiling in less than an hour.
The two curves of the cooker form an oval funnel that focuses the sun's rays on the cooking pot. The base of the cooker should be anchored with rocks or bricks as shown in the photo. On windy days, the bottom curve of the cooker can be prevented from being blown upward, by wrapping a circle of string around each side of the curve, and securing the string with the same brick or rock that is used to hold down the cooker. Cutting off the corners of the bottom curve will also reduce wind problems without affecting the cooker's performance, When the sun is high, the cut at the front bottom of the cooker can be overlapped and clipped together with a binder clip to form a kind of parabola to concentrate more sun on the cooking pot.
The Haines Polycarbonate Sleeve eliminates the nylon cooking bag commonly used in solar cooking. This sleeve is a 6" x 36" rectangle of UV-stabilized polycarbonate plastic film (.020"), such as Bayer Bayfol UV-1-72, or Lexan 8030, which is rolled into a cylinder to enclose the bottom and sides of the pot but not the top. The cylinder is held together with jumbo paper clips, thus allowing its diameter to be adjusted to fit a variety of cooking pots The pots must be round, with no handles, and must have a top rim that can rest on the top of the cylinder. The cylinder elevates the pot above the surface of the cooker, allowing the sun's rays to bounce off the reflective surface of the cooker and be absorbed by the bottom of the cooking pot. It also provides an insulating "greenhouse" making a traditional cooking bag unnecessary. Haines's testing indicates that a pot with a glass lid retains more heat than one with a metal lid.
Kirkpatrick Solar Cooker (Kirk-ook) variation
Mark Evans Kirkpatrick has offered modifications to the Haines Solar Cooker, known as the Kirk-ook. The base reflector is slotted through the rear reflector to provide more stability for the cooker in windy conditions (with less base material extended and more base material supported). The bottom-rear of the cooker can be supported with rocks as shown in the picture. By extending the sides you will create a wave-like formation focusing more rays in the center for higher effectiveness (depending on the angle of the sun). Higher temperatures can be reached using a turkey bag around the pot & lid on windy days (alleviating the effect from high winds, elevating the pot 2" with black rocks) . The plastic film can be coated with UV agents to avoid discoloration and distortion. Alternate transparent plastics are being tested for higher heat resistance (*email suggestions). It is recommended using clear packaging tape to cover each area that is cut (easier when applied prior to cutting out the design) on each side of the cooker. Tape can also be added to other areas prone to wear-and-tear (mainly the latching triangles that replaced the Velcro or binder clips).
- See Roger Haines.
Mark Evans Kirkpatrick