Test Results

Haines 2 Heats Twice as Fast as Popular “CooKit” solar cooker

At noon on June 30, 2019, we conducted a side-by side test of a Haines 1 and a Haines 2 Solar Cooker along with two popular “CooKit” solar cookers.  The four cookers were set up on a single piece of cardboard in the shade.  The sun was about 80 degrees directly overhead.  The sky was clear and there was an occasional breeze.  The ambient temperature was around 86 F. (30 C.) throughout the test (as shown by the bold line at the bottom of the graph below). 

The pots in each cooker were identical 4 ½ liter stainless steel Haines Dutch ovens with glass lids.  Each pot had one liter of water taken from a common bucket.  The two Haines cookers and one CooKit used a Haines cooking sleeve and circular cover.  [Note: the cover did not fit the CooKit very well.]  The other CooKit enclosed the pot in it recommended plastic cooking bag, on a 1-inch-high wooden trivet.  Both CooKits were set for high sun, with the front flap up as high as it would go. The Haines 2 was set for high sun (red snaps).  The Haines 1 was not adjusted in any way.

A thermocouple wire was inserted through the steam vent in each glass lid, into the water.  The wires were connected to a HOBO Onset 4-channel thermocouple logger. The logger was started at 12:21 p.m., and the cardboard with the four cookers on it was pulled into the sun.

Haines Solar Cookers Test Results

Observations:  As shown on the graph below, the Haines 2 boiled the water in 48 minutes, followed by the Haines 1 in 65 minutes, the CooKit with the Haines cooking sleeve and circular cover in 86 minutes, and the CooKit with the plastic bag in 100 minutes. The cardboard was turned four times during the test, to follow the sun.  We noted that below 40C., the CooKit withthe circular cover heated more slowly than the Cooker withoutthe circular cover.  But above 40 C. the CooKit with the cover heated faster—apparently because the cover retained more heat than it blocked at temperatures above 40 C.  This confirms earlier tests that showed similar results.  Thus it appears that the performance of the CooKit can be improved by replacing the plastic bag with a Haines Cooking sleeve and circular cover. However, even with these improvements, the CooKit took 21 minutes longer than the Haines 1 to boil the water. 

Test Results Chart

Conclusion:  When the sun is high in the sky, the Haines 2 can boil a liter of water in under 50 minutes—more than twice as fast as the CooKit with a plastic cooking bag. Under the same conditions, the Haines 1 can boil a liter of water in 65 minutes, i.e., in only 65 percent of the 100 minutes it takes for the CooKit with a plastic bag. 

Other Tests

We have found side-by-side testing to be the best method for determining the performance of solar cooking designs.  Indeed this is the method we have used to perfect the Haines 1 and Haines 2 designs. Over the years, we have performed similar side-by-side tests comparing the Haines 1 or 2 to all the leading panel and box cookers, at all times of the day.  No other cooker has exceeded the performance of the Haines models, and many of them failed even to reach cooking temperatures, on days when the Haines cookers boiled the water.  These photos show some of the cookers we have tested.