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This paper analyzes and presents the thermodynamic cycles and the experimental performance parameters of a solar adsorptive icemaker that uses activated-carbon methanol pair. The solar energy technology employed is far less sophisticated than that of collectors using selective surface or evacuated tubes. The collector-adsorber is multi-tubular with an opaque black radiation-absorbing surface, and thermal insulated by means of transparent covers, the so-called transparent insulation material (TIM). The solar radiation hits on both faces of the tubes by means of semi-cylindrical reflectors. It is shown the results of tests carried out in a region of Brazil close to the Equator, on days characterized by the predominant cloud cover degree. Three cycles have been analyzed: one with clear sky, another with partially cloudy sky, and a third under entirely cloudy sky. The maximum regenerating temperatures were 100.1, 87.3 and 92.7 °C, with an ice production of 6.05, 2.10 and 0 kg by square meter of projected area, for cycles of clear sky, partially cloudy and overcast nights, respectively.

Adsorptive cycles are well adapted to solar refrigeration. Solar ice makers (with an activated carbon + methanol pair) are described. Their major originality lies in the assembly of solar collector and condenser in a unique component: the collecto-condenser. A ‘standard’ ice maker and two prototypes were tested in actual conditions in Agadir, Morocco and this operation is described. Performances are quite good in Agadir; units produce more than 4 kg/m2 of ice for more than 60% of the days investigated.

Performances of the solar powered ice-makers tested in Agadir, Morocco, as described in [1], are studied. Experimental data are sufficient for establishing a statistical correlation between heat extraction and meteorological parameters: insolation, diurnal and nocturnal temperatures. The influences of these parameters are also evaluated through operation analysis. Both approaches are rather consistent. Nocturnal temperature appears to be a quite important factor. Indeed, cold nights (around 10°C) largely increase production. Meteorological conditions for producing either just no ice at all or 5.2 kg, are investigated, as well as an evaluation of yearly production: in Agadir, the average daily production lies around 4 kg/m 2 . With a nocturnal cooling system, the units would produce around 1 kg more. From the economic point of view, small units such as those tested herein are too expensive, but solarization of a pre-existing cold store in isolated areas looks competitive.