Abstract
In this paper, an off-grid hybrid power plant with multiple storage systems for an artificial island is designed and two possible strategies for the management of the stored energy are proposed. Renewable power sources (wind/solar technologies) are used as primary power suppliers. A lead-acid battery pack (BAT) and a reversible polymer electrolyte fuel cell are employed to fulfill the power demand and to absorb extra power. The reversible fuel cell allows reducing costs and occupied space and the fuel cell can be fed by the pure hydrogen produced by means of its reversible operation as an electrolyzer. A diesel engine is employed as backup system. While HOMER Pro® has been employed for a full-factorial-based optimization of the sizes of the renewable sources and the BAT, Matlab/Simulink® has been later used for simulating the plant operation and compare two possible power management control strategies. For the reversible fuel cell sizing, a sensitivity analysis has been carried out varying stack and hydrogen tank sizes. The final choice for plant configuration and power management control strategy has been made on the basis of a comparative analysis of the results, aimed at minimizing fossil fuel consumption and CO2 emissions, battery aging rate and at maximizing the power plant overall efficiency. The obtained results demonstrate the possibility of realizing a renewable power plant, able to match the needs of electrical power in a remote area, by achieving a good integration of different energy sources and facing the intermittent nature of renewable power sources, with very low use of fossil fuels.
Highlights
TUNeIT (TUNisia and ITaly) project—part of the MedTracking research program carried out by the Network of Schools of Engineering in the Mediterranean RMEI (Réseau des Ecoles des IngenieursMéditerranéen) [1]—proposes to link the Sicilian coast to the Tunisian one, for a total length of about140 km, by creating five bridges, with the same characteristics of the one of the Messina project, starting from and arriving to four artificial islands
The same electrical load profiles used in the components sizing phase and shown in Figure 2 have been used for the simulation of the power plant operation
A set of parameters has been chosen to compare the performance of the two strategies and namely: battery state of charge, hydrogen tank level, diesel fuel consumption, battery aging rate and lifetime, energy consumed by the compressor and power plant overall efficiency ηPP
Summary
TUNeIT (TUNisia and ITaly) project—part of the MedTracking research program carried out by the Network of Schools of Engineering in the Mediterranean RMEI Tool is employed [10], resulting in a slight oversize of wind and solar power converters, in order to produce as much power as possible during windy and sunny days, while a sensitivity analysis has been performed to find a size of the RePEM which allows a trade-off between fossil fuel usage by the diesel generator and battery aging rate. A rule-based approach has been implemented for the plant power management strategies because of its reliability, and the strategies have been reproduced and verified by means of a self-made simulation tool developed in Matlab/Simulink® r2014a (The Mathworks, Inc., Natick, MA, USA) In both the proposed strategies, wind and solar energy sources are used as primary power suppliers, while the RePEM, together with the BAT, are employed to fulfill the power demand—when the power supplied by the renewable power generators is not sufficient—or to absorb excess power, when available. The BAT is always used as primary energy recovery system, followed by the RePEM in electrolyzer mode if needed, while the extra power demand is satisfied first by the battery and by the RePEM in fuel cell mode in one case and vice versa in the second case
Sign-in/Register to view highlights & summary 
Published Version (
Free)
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call