Process Integration techniques for optimal design of hybrid power systems

Power Pinch Analysis (PoPA) is a technique for the optimal power allocation in hybrid systems comprising of renewable energy sources. The graphical PoPA tools have recently been proposed to determine targets for the minimum amount of outsourced electricity and the maximum amount of excess electricity to be stored and reused in the hybrid power systems. The numerical techniques for PoPA have so far not been developed. This work introduces two new PoPA numerical tools known as the Power Cascade Analysis (PoCA) and the Storage Cascade Table (SCT). The tools can be used to determine (1) the minimum target for outsourced electricity, (2) the amount of excess electricity for storage during start up and normal operations, (3) the amount of transferrable power, (4) the maximum storage (e.g. battery) capacity for the off-grid systems, (5) the amount of electricity transferrable to the grid, (6) the amount of outsourced electricity needed at each time interval and (7) the time interval where the maximum power demand occurs. While the graphical techniques provide useful visualisation insights, the numerical tools enable more rapid and precise allocation of power as well as the determination of electricity targets. (C) 2013 Elsevier Ltd. All rights reserved.