A Numerical and Graphical Review of Energy Storage Technologies

More effective energy production requires a greater penetration of storage technologies. This paper takes a looks at and compares the landscape of energy storage devices. Solutions across four categories of storage, namely: mechanical, chemical, electromagnetic and thermal storage are compared on the basis of energy/power density, specific energy/power, efficiency, lifespan, cycle life, self-discharge rates, capital energy/power costs, scale, application, technical maturity as well as environmental impact. It’s noted that virtually every storage technology is seeing improvements. This paper provides an overview of some of the problems with existing storage systems and identifies some key technologies that hold promise

Mechanical Systems for Energy Storage – Scale and Environmental Issues. Pumped Hydroelectric and Compressed Air Energy Storage

This chapter introduces large-scale utility (bulk) energy storage in the form of pumped hydroelectric and compressed air energy storage. Both are mechanical energy storage technologies, converting electrical energy into potential energy, and both fall into the category of grid-scale energy management. Brief reviews and discussions relating to the general operational aspects and the legislative and environmental aspects of the two storage types are provided in the context of UK development. Both storage technologies offer the potential for better integration and penetration of renewable electricity sources and the reduction of greenhouse gas emissions

Study on a hybrid wind turbine system with Intrinsic compressed air energy storage provision

Recent years have witnessed the expansion of the wind power industry, spawned from international legislation that commits countries to increasing their share of renewable energy, compared to their gross energy consumption. However, increased exploitation of wind power poses challenges for power network operation. The variability and uncertainty of wind power may lead to network capacity constraints, system stability issues and potential wind power curtailment in the near future. Energy storage is considered to be one of the most viable options to support the integration of increased wind power to the power network. This project is concerned with developing a hybrid wind turbine with intrinsic compressed air energy storage provision, so that the power output of a wind turbine can be controlled, thus providing flexibility. The proposed hybrid wind turbine makes use of compressed air energy storage on a turbine level. An efficient power split device in the form of a planetary gear box is designed to couple a horizontal axis wind turbine with a scroll air expander/compressor machine, i.e. a single device that can swap its operation, and a permanent magnet synchronous generator/motor. The hybrid wind turbine can operate in conventional standalone fashion. In addition, power can be added and taken away to/from the system through the expansion and compression mode. The hybrid wind turbine also offers standalone energy storage provision, so that power can be extracted from the grid and returned at later times. The whole system mathematical model is derived and successfully validated by means of a small scale experimental test rig. Equipped with feedback control, the hybrid wind turbine can smooth the generated power output under varying wind speeds. Following this, efficiency analysis is carried out in this thesis and a feasibility study on a 1MW hybrid wind turbine is conducted. The results obtained from the project demonstrate that the proposed hybrid wind turbine system is feasible and that it can help improve the wind turbine efficiency in addition to smoothing the power output. Therefore, it can be a valuable asset for wind power integration into the power network