Designing Organic Rankine Cycle Plants Based on a Design to Resource Method
This paper discusses a methodology for analysing and optimization of organic Rankine cycle (ORC) designs using a new thermo-economic design to resource (DTR) method. The objective of the DTR method is to obtain the best designs, which are the closest match to the resource and the most cost-effective. The design analysis is constrained by the available main components and heat resource. The ratio of net power output to the total heat exchanger area is used as the objective function. The new design methodology was implemented on an existing lab-scale ORC as a case study. Experiments were conducted to obtain the data to identify the heat transfer coefficients of the real processes and validate the simulation model results. Design evaluations were carried out on the ORC plant by using three Capstone gas turbine load conditions and four design alternatives. The results indicate that design 1 has the highest objective function of all the design alternatives. It is able to increase the objective function from 100% to 391% of the base case depending on the Capstone gas turbine load conditions. The design to resource analysis reveals that the ORC plant is more suitable to Capstone load at condition 1 with the highest waste heat utilization rate (UR) of 76.9%.