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The large-scale production of renewable energy is limited by the intermittence nature of the renewable energy sources. Moreover, the electricity production of the thermal and nuclear power plants is not flexible with the electricity demand. Hence, the integration of energy storage technologies into the grid has become crucial as it creates a balance between supply and demand for electricity and protects thereby the electrical grid. Among the large-scale energy storage technologies, a novel adiabatic compressed air energy storage (A-CAES) system will be developed in this paper. This storage system is characterized, compared to the conventional compressed air energy storage (CAES) system, by the recovery and the reuse of the compression heat in order to improve the system efficiency and avoid the use of fossil fuel sources. This paper discusses a comparison between the static and dynamic modeling of the A-CAES system performed by a computer simulation using “Modelica.” Unlike the static model, the dynamic model takes into account the mechanical inertia of the turbomachinery (compressors and turbines) as well as the thermal inertia of the heat exchangers. Consequently, it enables studying the flexibility of the storage system and its ability to meet the electrical grid requirements (primary and secondary reserves) by evaluating the duration of the transient states. Furthermore, the comparison between the static and dynamic models permits to estimate the efficiency losses due to the transient evolutions.The results show that the storage system needs more than 2 min before being able to consume all the excess energy available on the electrical grid and more than 5 min before being able to produce all the energy required by the electrical grid. These time frames are due especially to the transient states (start-up) of the turbomachines. Finally, the system efficiency is 64.7%, the transient states of the system cause losses of 0.9%. These small losses are explained by the short duration of the transient states relative to that of the steady states (15 hrs).

Gas turbine systems are among potential energy converters to substitute the internal combustion engine in future series hybrid electric vehicle. Fuel consumption of these powertrains strongly relies on the energy converter efficiency, the energy management strategy deployed on-board as well as on the transient operation during start-up phase. This paper presents a dynamic modeling and the fuel consumption calculation of an intercooled regenerative reheat gas turbine system used as an auxiliary power unit on a series hybrid electric vehicle. A vehicle model is developed and an optimization method is proposed to optimize the powertrain operation. It consists of using the dynamic programing as an energy management strategy in order to minimize the fuel consumption and the number of switching On/Off of the power unit. Fuel consumption simulations are performed on the worldwide-harmonized light vehicles test cycle while considering the electric and the thermal comfort vehicle energetic needs. Then, a gas turbine dynamic model is developed, where turbomachinery and heat exchanger components are modeled by taking into account their dynamic inertias. The efficiency, the power, and the fuel consumption are calculated during transient operations. Based on the optimization results of switching ON and OFF the system, the fuel consumption dynamic simulation results are considered instead of the dynamic programming results. A constant power start-up strategy and a constant fuel strategy were investigated. Results show an increase in fuel consumption between 2.4% and 3.8% with the first start-up scenario and between 5.7% and 6.4% with the second scenario, compared with static model.