Thesis (MEng)--Stellenbosch University, 2019. ; ENGLISH ABSTRACT: The rapid increase in demand for solar energy and its contribution to the national grid has placed new emphasis on the performance of Concentrating Solar Power (CSP) Plant. Plant performance can be enhanced by using once-through watercooling instead of the conventional direct air-cooled systems. Water withdrawn from the Orange River for agricultural irrigation purposes near Upington, in the Northern Cape can accommodate once-through cooling. To achieve this, a detailed study of CSP plant and different types of the cooling systems that are available was undertaken. The different types of CSP plant were evaluated and the best CSP plant based on the technology advancement was identified. The use and management of the irrigation system, government policies and environmental legislation along the lower Orange River was studied to look for synergy between CSP and agricultural water use. Once-through cooling for CSP plant that is also known as open-cycle cooling was modelled and fully analysed. The components of the CSP plant were also modelled, with emphasis on condenser fouling. This includes heliostat field, receiver tower, thermal storage, steam generator and power block. The heliostat field model determined the heliostat field optical efficiency over the year. The power block model determined the thermal efficiency of CSP plant and the function of growth with the cooling water temperature in the cooling system. The model was also used to determine the impact of changing different CSP plant operating parameters on the cooling system and evaluate the plant output. All existing CSP plants, except Bokpoort, make use of direct air-cooled condensers. Hence, direct air-cooling was adopted as benchmark for this study. Compared to a direct air-cooled CSP plant, once-through cooling shows that there is an improvement in the thermal efficiency of 2.9 percentage points. The model is based on hourly fluctuations in cooling water temperature from the river that ...