Optimization Research On Combined Cooling,Heating,and Power System

With the concept of sustainable development in the world appear worldwide on issues such as energy consumption, environmental pollution and other effects. In this paper, combined cooling, heat and power (CCHP) technology is getting more and more attention in the construction sector. Because the CCHP system is relatively complex, to configure the capacity and optimize the operation strategy has become an important issue in using of CCHP system. In order to optimize the CCHP system configuration and operation strategy, we propose a two-stage optimization design method which can not only implement multiple design goals, but also to find the best strategy designed to run within the period. In the first stage of optimization, taking total non-dominated sorting based on multi-objective genetic algorithm (NSGA-II), the optimal goal is to minimize total lifecycle present costs value and the hydrocarbons, nitrogen oxides, sulfur dioxide, particulate matter emissions, the optimal solution is to find a more appropriate set of device type and equipment capacity, so that economic and environmental goals to achieve the optimum. In the second stage uses a mixed-integer linear programming (MILP) algorithm to solve the optimal scheduling problem, this phase is to achieve the lowest operating costs and operational strategies hourly. The second stage is based on the first stage of optimization, using the operation strategy of the first stage of the optimization to calculate the cost of fuel and electricity for the second stage optimization, and then get the present value of the life cycle. Because the hospital’s load is heavy and steady, it is the right place applying CCHP system. A hospital annual hourly load is calculated with Designer’s Simulation Toolkit (DeST). Using the two-stage design optimization method, the economic and environmental goals of Pareto optimality, and best operation strategy is found, so the method is proved to be effective.