OPTIMISATION OF ENERGY AND WATER SUPPLY SYSTEMS FOR THE DUBAI WATERFRONT

摘要

This paper details a study, carried out in collaboration with the main project architects, to support the infrastructure design of the Dubai Waterfront, a new city for 1.5 million people. The goal was to establish, balancing economics and environmental impact, the best combination of primary energy supply and conversion technologies required to meet electricity, heating, cooling, chilled and potable water requirements for the new city, for which prior analysis had defined detailed demand profiles (variable hourly, daily and seasonally). A multi-objective MILP optimisation model was developed which included the key generation, transformation, storage and utilisation options, together with financial (capital and operating cost) and CO2 emission models of each. After an initial screening, primary energy supply technologies considered included: Combined cycle gas turbine (CCGT), Solar photovoltaics, Solar thermal (parabolic troughs), Large scale on-shore wind power and Waste to energy. For water desalination, both thermal (in particular Multiple effect distillation) and electromechanical processes (in particular Reverse Osmosis) were considered as potentially viable. For cooling, options selected included Absorption chillers and Vapour compression chillers. While storage of electricity was not considered feasible, options to store chilled and potable water were included. Key aspects of the approach and model, some of the data used, and representative results are described. The model, implemented and solved in GAMS, provided a consistent framework for the comparison of alternative technologies, the trade-offs between cost and emissions and the assessment of deployment scenarios. Results include some unexpected findings arising from the complex interactions between demand variations and energy, water and water storage components. In particular, storing chilled water in insulated storage tanks and potable water in exposed but deep lakes represented an effective way to store energy, minimise peak energy supply, and reduce both capital and CO2 emissions.