Abstract: The invention is a solar powered heat exchanger (10) comprising a solar collector (12), a heat accumulator (14), and a heat exchanger (16). The solar collector is operatively coupled to the heat accumulator (14) via a supply line (18) and a recirculation line (20). The heat accumulator (14) is in turn operatively coupled to the heat exchanger (16) via a feed line (22) and a return line (24).

Abstract: In one aspect of the present invention there is provided a method for condensing water from ambient air, the method comprising: providing at least one condensation surface for contact with the ambient air; heating a solution of a refrigerant and a fluid, to drive gaseous refrigerant from the solution; cooling the gaseous refrigerant to condense the gaseous refrigerant into liquid refrigerant, and collecting the liquid refrigerant; evaporating refrigerant from the liquid refrigerant such that heat is exchanged between the refrigerant and the condensation surface which is thereby cooled to, or below, the dew point of the water in the ambient air; and contacting the cooled condensation surface with the ambient air to effect condensation of water from the ambient air onto the condensation surface.

Abstract: There is provided methods and apparatus (2) for collecting water from ambient air. The apparatus has at least one condensation surface which is cooled to, or below, the dew point of the ambient air. The cooling of the condensation surface is effected by utilising a gas to reduce the partial pressure of refrigerant vapour to effect evaporation of liquid refrigerant. Water in ambient air that contacts the cooled condensation surface condenses and is collected. There is also provided apparatus for effecting cooling and/or heating.

Abstract: There is disclosed lighting apparatus suitable for being positioned adjacent to an area or an object for indicating the location or orientation of the area or object. The apparatus is provided with a set of light emitters for emitting light and which are positioned side by side relative to one another. The light emitters are staggered for emitting the light outwardly from the apparatus at an increasing angle along the set relative to a plane of reference. In a particularly preferred embodiment, the light emitters are light emitting diodes. The apparatus finds particular application as an airstrip light for indicating the position and orientation of the airstrip to approaching aircraft. Signalling apparatus for being positioned adjacent to an area for indicating the position of the area and which are provided with infrared emitting diodes for emitting an infrared signal are also described.

Abstract: There is disclosed lighting apparatus suitable for being positioned adjacent to an area or an object for indicating the location or orientation of the area or object. The apparatus is provided with a set of light emitters for emitting light and which are positioned side by side relative to one another. The light emitters are staggered for emitting the light outwardly from the apparatus at an increasing angle along the set relative to a plane of reference. In a particularly preferred embodiment, the light emitters are light emitting, diodes. The apparatus finds particular application as an airstrip light for indicating the position and orientation of the airstrip to approaching aircraft. Signalling apparatus for being positioned adjacent to an area for indicating the position of the area and which are provided with infrared emitting diodes for emitting an infrared signal are also described.