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The Sunseed Trust is a UK registered charity that does research intended to help peoples living in arid and near desert areas. Sunseed Desert Technology is their research centre near Almeria in south eastern Spain, the region with the most parching climate in Europe.
I attended Sunseed's Desert Technology Research Centre in June 1996 to learn about their research and to test the Anahat type of solar cooker designed by Anna Pearce of Box-Aid. The cookers are essentially a 90 degree cone of Mylar, 40cms across the opening, oriented towards the sun, the food being placed in a blackened container, covered by a clear plastic baking bag, sitting in the centre of the cone.
Three variants of the Anahat were tested:
- A-1: the Mylar was backed with 1cm thick polyurethane foam. The cooker was sat in a "Wonderbox", a polystyrene filled cushion. The container was an open, black painted, tin can of approx. 900cc capacity.
- A-2: the Mylar was backed with 1cm thick polyurethane foam. The cooker was sat in a large cooking pot. The container was a black painted tea kettle of approx. 750cc.
- A-3: the Mylar was supported by a similar aluminium cone. The cooker was sat in a "Wonderbox". The container was an open, black painted, tin can of approx. 1300cc capacity.
I conducted the tests on Wednesday the 26th of July, 1996, at the Sunseed Desert Technology research centre near Sorbas, Almeria, Spain (36°N, 2°W) in line with their testing methodology. Sunseed's ULOG and Adobe cookers were used for comparison.
500cc of sunflower oil was placed in each test container. Weather conditions were 1 to 4 eights cumulus cover with 1 to 3 force winds. Each cooker was aligned once an hour on the hour.
| Environment | ULOG Box Cooker | Adobe Ref. Cooker | Anahat Cookers | |||||||||
| Amb. | Wind | Small | Large | Base | Small | Large | Base | |||||
| Time | Temp. | Speed | Pot | Pot | Plate | Pot | Pot | Plate | A-1 | A-2 | A-3 | Notes |
| 11:00 | 25 | a | ||||||||||
| 12:00 | 25 | 102 | 108 | 95 | 87 | 67 | 67 | 117 | 103 | 117 | a | |
| 13:00 | 27 | 40 | 67 | 78 | 28 | 34 | 70 | 38 | 25 | 29 | b | |
| 13:15 | b | |||||||||||
| 13:30 | 28 | 1.04 | 60 | 72 | 90 | 48 | 55 | 75 | 68 | 38 | 53 | |
| 13:45 | 29 | 1.71 | 73 | 87 | 96 | 58 | 63 | 79 | 81 | 60 | 70 | |
| 14:00 | 29 | 1.91 | 80 | 92 | 92 | 61 | 61 | 79 | 83 | 65 | 73 | |
| 14:15 | 29 | 2.39 | 89 | 101 | 103 | 67 | 69 | 76 | 99 | 75 | 86 | |
| 14:30 | 29 | 1.80 | 97 | 108 | 110 | 68 | 70 | 80 | 110 | 86 | 94 | |
| 14:45 | 29 | 1.91 | 102 | 116 | 112 | 70 | 75 | 81 | 116 | 94 | 102 | |
| 15:00 | 28 | 1.59 | 106 | 120 | 116 | 74 | 76 | 80 | 117 | 97 | 102 | |
| 15:15 | 29 | 2.52 | 109 | 121 | 116 | 79 | 80 | 93 | 120 | 104 | 104 | |
| 15:30 | 28 | 2.13 | 112 | 124 | 114 | 83 | 83 | 92 | 120 | 107 | 103 | |
| 15:45 | 27 | 1.94 | 116 | 126 | 116 | 88 | 86 | 92 | 117 | 109 | 101 | |
| 16:00 | 27 | 2.76 | 116 | 128 | 117 | 91 | 90 | 92 | 114 | 109 | 100 | |
| 16:15 | 27 | 2.09 | 118 | 129 | 116 | 88 | 91 | 93 | 114 | 112 | 100 | |
| 16:30 | 26 | 2.99 | 119 | 132 | 119 | 89 | 94 | 94 | 114 | 114 | 100 | |
| 16:45 | 26 | 2.53 | 121 | 133 | 120 | 88 | 93 | 98 | 111 | 114 | 99 | |
| 17:00 | 26 | 3.01 | 120 | 133 | 120 | 89 | 94 | 94 | 104 | 111 | 95 | |
a) Cookers and pots were preheated for two hours before adding the oil.
b)
Due to operational difficulties the 13:00 readings may be inaccurate, and the
13:15 readings were missed.
All temperatures are in degrees Celsius. Wind speeds are in metres per second. Times are local time (CET), being solar time plus approximately one hour.
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