Constraints of the Water Use Model

Abstract

The model constraints for the flow variables are introduced for the consumption good amounts and the required raw materials. The constraints for the water, wastewater, and energy amounts are formulated as well as those for sustaining and developing the capital stock variable. The relation between the human labour inputs and the capital stock reflects the technological progress within the model. The development of the capital stock depends on the path for the consumption good and the time preference of the target, or inter-temporal, welfare function. The number of variables in the system of constraints will be reduced by substituting the capital good amounts and the accumulated capital stock with the consumption good amounts. This substitution will be done using the so-called no-storage assumption. This assumption also allows the aggregation of process inputs to sector inputs, which simplifies the determination of the optimality conditions.