Aqueous batteries as grid scale energy storage solutions

Energy storage technologies are required to make full use of renewable energy sources, and electrochemical cells offer a great deal flexibility in the design of energy systems. For large scale electrochemical storage to be viable, the materials employed and device production methods need to be low cost, devices should be long lasting and safety during operation is of utmost importance. Energy and power densities are of lesser concern. For these reasons, battery chemistries that make use of aqueous electrolytes are favorable candidates where large quantities of energy need to be stored. Herein we describe several different aqueous based battery chemistries and identify some of the research challenges currently hindering their wider adoption. Lead acid batteries represent a mature technology that currently dominates the battery market, however there remain challenges that may prevent their future use at the large scale. Nickel–iron batteries have received a resurgence of interest of late and are known for their long cycle lives and robust nature however improvements in efficiency are needed in order to make them competitive. Other technologies that use aqueous electrolytes and have the potential to be useful in future large-scale applications are briefly introduced. Recent investigations in to the design of nickel–iron cells are reported with it being shown that electrolyte decomposition can be virtually eliminated by employing relatively large concentrations of iron sulfide in the electrode mixture, however this is at the expense of capacity and cycle life

Utility/Industry Partnerships Involving Distributed Generation Technologies in Evolving Electricity Markets

Electricity markets in the United States are undergoing unprecedented structural changes as a result of the confluence of regulatory, competitive, and technological forces. This paper will introduce the role of distributed generation technologies in evolving electric markets and will review both current and emerging distributed generation technologies aimed at retail industrial, commercial and residential markets. This paper will draw upon several Electric Power Research Institute’s (EPRI) and member utility case studies involving the assessment of distributed generation in premium power service, standby power and industrial cogeneration applications. In addition, EPRI products and services which can help evaluate energy service options involving distributed generation will also be briefly reviewed

Demonstration of a Carbonate Fuel Cell on Coal Derived Gas

Several studies indicate that carbonate fuel cell systems have the potential to offer efficient, cost competitive, and environmentally preferred power plants operating on natural gas or coal derived gas (“syn-gas”). To date, however, no fuel cell system has run on actual syn-gas. Consequently, the Electric Power Research Institute (“EPRI”) has sponsored a 20 kW carbonate fuel cell pilot plant that will begin operating in March at Destec Energy’s coal gasification plant in Plaquemine, Louisiana. The primary purpose of the test is to determine the effect of syn-gas contaminants on the performance and life of the carbonate fuel cell. This paper will describe the project objectives, design aspects of the pilot facility, and the status of the project