Water Temperature Regimen Analysis of Intensive Fishfarms associated with Cooling Effluents from Power Plants

This work analyses the effect that the electrical market liberalisation has on the variation of water temperature regimes in intensive aquaculture plants, and more specifically, the fishfarms which take advantage of the cooling effluents from power plants. Data were obtained from a facility devoted to the European eels growth which takes the warm water from the cooling effluent from the Puente Nuevo thermal power plant (Córdoba, Spain). The results indicate that the liberalisation of the electrical network has a significant influence on the form and quantity of energy generated by the thermal power plant, and consequently on the thermal regimes of the cooling effluent. A decrease in the mean water temperature (mean water temperature before liberalisation=25·5 °C and after liberalisation=24·3 °C) and an increase of variation range of water temperature (standard deviation before liberalisation=1·7 °C and after liberalisation=2·5 °C) inside the fishfarm were observed (without modify the management scheme of the production system) when the electrical market liberalisation was implemented. The growth potential of reared eels estimated from a growth capacity index (GCI) showed significant differences between the mean values in the regulated and liberalised electrical markets. The decrease in the value of GCI was 6·67% when the electrical market liberalisation was implemented.