Exergoeconomic optimisation of steam networks connecting solar-thermal dish arrays

Abstract

We optimise steam network trees that connect Big Dish paraboloidal collectors to a central power block. Exergy costs, pipe material costs, and installation costs are estimated using an exergoeconomic model and used to optimise pipe links in network trees. The optimal network tree is then found for a 10MW<inf>e</inf> collector field using a genetic algorithm. An optimised tree is found for a 20MW<inf>e</inf> network. The optimised 20MW<inf>e</inf> network has additional east-west branches not seen in the optimal 10MW<inf>e</inf> network, that reduce steam transport costs from network extremities. Exergy costs from heat loss and pressure drop account for approximately 60% of total network cost in both cases. Total network costs are, respectively, 8.9% and 9.5% of potential plant revenue for the 10MW<inf>e</inf> and the 20MW<inf>e</inf> networks.