Towards Implementation of Smart Grid: An Updated Review on Electrical Energy Storage Systems

A smart grid will require, to greater or lesser degrees, advanced tools for planning and operation, broadly accepted communications platforms, smart sensors and controls, and real-time pricing. The smart grid has been described as something of an ecosystem with constantly communication, proactive, and virtually self-aware. The use of smart grid has a lot of economical and environmental advantages;however it has a downside of instability and unpredictability introduced by distributed generation (DG) from renewable energy into the public electric systems. Variable energies such as solar and wind power have a lack of stability and to avoid short-term fluctuations in power supplied to the grid, a local storage subsystem could be used to provide higher quality and stability in the fed energy. Energy storage systems (ESSs) would be a facilitator of smart grid deployment and a “small amount” of storage would have a “great impact” on the future power grid. The smart grid, with its various superior communications and control features, would make it possible to integrate the potential application of widely dispersed battery storage systems as well other ESSs. This work deals with a detailed updated review on available ESSs applications in future smart power grids. It also highlights latest projects carried out on different ESSs throughout all around the world.

Overview of Energy Storage in Renewable Energy Power Fluctuation Mitigation

The integration of renewable energy,such as PV and wind power,has exerted great impacts on the power system with its rapid development.If the corresponding energy storage system is configured,the power system could be able to hold a higher proportion of renewable energy.Focusing on energy storage application for the output fluctuation mitigation of renewable energy,this paper first analyses the reason for renewable energy power fluctuation mitigation from the four aspects of frequency,unit ramp,low frequency oscillation and cascading failure.In addition,the fluctuation rate standard of grid-connected renewable energy,the energy storage type and the mitigation topology are introduced.Then a summary and analysis on mitigation strategy and hybrid energy storage allocation strategy are presented.Finally,the demonstration application and development trend of energy storage are analyzed to provide reference for the promotion of energy storage in renewable energy.

A PVTC system integrating photon-enhanced thermionic emission and methane reforming for efficient solar power generation

A new photovoltaic-thermochemical(PVTC) conceptual system integrating photon-enhanced thermionic emission(PETE) and methane steam reforming is proposed. Major novelty of the system lies in its potential adaptivity to primary fuels(e.g. methane) and high efficiencies of photovoltaic and thermochemical power generation, both of which result from its operation at much elevated temperatures(700–1000 °C)compared with conventional photovoltaic-thermal(PVT) systems. Analysis shows that an overall power generation efficiency of 45.3% and a net solar-to-electric efficiency of 39.1% could be reached at an operating temperature of 750 °C, after considering major losses during solar energy capture and conversion processes. The system is also featured by high solar share(37%) in the total power output, as well as high energy storage capability and very low CO_2 emissions, both enabled by the integration of methane reforming with photovoltaic generation at high temperatures.

Dual degree branched type-2 fuzzy controller optimized with a hybrid algorithm for frequency regulation in a triple-area power system integrated with renewable sources

The uncertainties associated with multi-area power systems comprising both thermal and distributed renewable generation(DRG)sources such as solar and wind necessitate the use of an efficient load frequency control(LFC)technique.Therefore,a hybrid version of two metaheuristic algorithms(arithmetic optimization and African vulture’s optimization algorithm)is developed.It is called the‘arithmetic optimized African vulture’s optimization algorithm(AOAVOA)’.This algorithm is used to tune a novel type-2 fuzzy-based proportional–derivative branched with dual degree-of-freedom proportional–integral–derivative controller for the LFC of a three-area hybrid deregulated power system.Thermal,electric vehicle(EV),and DRG sources(including a solar panel and a wind turbine system)are con-nected in area-1.Area-2 involves thermal and gas-generating units(GUs),while thermal and geothermal units are linked in area-3.Practical restrictions such as thermo-boiler dynamics,thermal-governor dead-band,and genera-tion rate constraints are also considered.The proposed LFC method is compared to other controllers and optimizers to demonstrate its superiority in rejecting step and random load disturbances.By functioning as energy storage ele-ments,EVs and DRG units can enhance dynamic responses during peak demand.As a result,the effect of the afore-mentioned units on dynamic reactions is also investigated.To validate its effectiveness,the closed-loop system is subjected to robust stability analysis and is compared to various existing control schemes from the literature.It is determined that the suggested AOAVOA improves fitness by 40.20%over the arithmetic optimizer(AO),while fre-quency regulation is improved by 4.55%over an AO-tuned type-2 fuzzy-based branched controller.