Abstract:
The water harvesting potential of atmospheric water generators (AWGs) in high-altitude
semiarid regions can be diminutive relative to the water generation capacity. Operational parameters
for the dehumidification process can be augmented to increase atmospheric water in the defined
zone available for harvesting. In this paper, the feasibility of augmenting the microclimates of AWGs
at the point of air extraction through an evaporative cooling system (ECS) was investigated. Water
yield and capacity utilisation were measured from two AWGs piloted on a plant in Ga-Rankuwa,
South Africa. This was implemented between December 2019 and May 2021. The study revealed
that although the ECS did impact the operating parameters through decreasing temperature and
increasing relative humidity (p < 0.05), variance in water yield was not significant (p > 0.05). Capacity
utilisation of the AWGs remained below 50% after augmentation. Cooling efficiency of the ECS
ranged between 1.4–74.5%. Energy expenditures of 0.926 kWh/L and 0.576 kWh/L for AWGs 1
and 2 were required under pristine conditions, respectively. Under the modified conditions, energy
expenditure decreased to 0.855 kWh/L for AWG 1, but increased/L to 0.676 kWh for AWG 2. ECS is
deduced to not be a feasible intervention for augmenting water harvesting potential for AWGs in this
semiarid zone.
