Wei-Jen Lee - US grants

Renewable energy sources including wind and solar can supply a significant amount of electrical energy in the US; however, because of their intermittent nature, the potential of these two energy sources can be fully exploited only if a suitable energy storage system is provided. Considering the requirements of energy capacity, efficiency and cost of this application, the hydrogen-bromine fuel cell has been identified as the most suitable electrical energy storage system. This system has many advantages among which are extremely fast reaction kinetics, high energy storage capacity, and high reliability. The potential was recognized by industrial teams which attempted to develop commercial systems; however, the use of expensive Pt-based catalysts on unstable electrode supports, the high cost, durable and high-performance membranes, and non-optimal cell configurations did not allow for widespread deployment of these fuel cells at the capacities required to have an impact on US energy requirements. The goal of this project is to generate the enabling science and create the engineering technologies needed to develop the regenerative hydrogen-bromine fuel cell system into a cost-effective, efficient, and reliable large-scale energy storage system for renewable energy sources. Four main focus areas have been identified: the design and synthesis of low-cost and durable eletrocatalysts with high reactivity and selectivity for the hydrogen and bromine reactions; the development of highly selective and durable proton conducting membranes for hydrobromic acid operation; the development of electrode microstructures and cell designs that minimize transport effects and maximize conversion efficiency; identification of system configurations and operation that are optimal for integration to the electrical grid. In terms of broader impacts, providing economical technologies to facilitate the transition from fossil fuels to sustainable energy sources is a grand challenge of the 21st century. Production of abundant, cheap, clean, reliable, renewable energy is the key, and the search for and commercialization of these energy sources will be the next great global industry. The discoveries, insights, and knowledge gained from this project will have impacts on other electrochemical power systems and may find applications in areas such as electric vehicles and residential/commercial power. The educational and outreach component of this project will help create a new diverse generation of engineers and researchers who will play a major role in development of this technology and the creation of a new energy industry. The outcome of this project will contribute to fundamental advances in electrocatalysis, polymer science, electrode design, nano-manufacturing and integration of large-scale energy storage to the electrical grid.

The FY 2010 EFRI-SEED Topic that supports this project was sponsored by the US National Science Foundation (NSF) Directorates for Engineering (ENG), Mathematical and Physical Sciences (MPS) and Social, Behavioral and Economic Sciences (SBE), and Computer & Information Science and Engineering in collaboration with the US Department of Energy (DOE) and the US Environmental Protection Agency (EPA).

1135368 (Nguyen). Our electrical grids are currently overloaded because of simultaneous peak electrical energy demand. This simultaneous demand sets the peak power generation level for power plants and peak power delivery capacity of the electrical grids. The peak power demand in the US and around the world is expected to increase significantly as the population grows and electrification of transportation is implemented. This creates a significant pressure for the need to build new power plants and upgrade the electrical grids. While the total daily electrical energy demand is fairly constant, its distribution rate (power) is not uniform with daytime load being almost double the night time load. If we can create a way in which this total daily energy demand is delivered at a constant rate, our existing electrical power plants and grids, which were designed for peak power, could produce and transmit energy more efficiently and economically. Furthermore, new power plants deployment and electrical grid upgrades or replacement can be done at a rate that is more manageable and less disruptive. A concept that may make this possible is to store electrical energy locally at the ?point of use? when demand is low or not needed for use when it is needed. An example of this is to buy and store electricity at night, when the demand and cost are low, for use in the day time when the demand and cost are high. This distributed energy storage approach allows the power plants and electrical grids to operate at more economical and sustainable levels. This one-year proposed project plans to conduct a systems and economics study of this concept and its impacts on the current energy production and distribution systems. Two storage applications will be evaluated, phase change systems for air-conditioning, a major use of electrical energy, and electrochemical storage systems (stationary batteries, flow batteries and fuel cells). The research team will identify the requirements of each application and determine the minimum round-trip storage efficiency and costs that these systems must have to be competitive using existing price differences. They will determine the percent of power plant and grid capacity that will become available when local energy storage capacity is used in various application sectors (commercial and residential). This work will be done by two undergraduate students, one each from Chemical Engineering and Electrical Engineering. The results generated will be used in an elective course called ?Energy for Sustainability? that the PI is developing for all disciplines in the school of engineering at the University of Kansas. This distributed energy storage concept may have a transformational impact on our current electrical energy production and transmission infrastructures. The data generated by this study will be very useful to the energy generation and transmission industries and the research community. Finally, this research will serve as an excellent venue to introduce issues on energy and environmental sustainability to the participating undergraduate students and to contribute to the development of a workforce that is more knowledgeable of these sustainability issues.

The objective of this research is to develop a method for integrating design and power management of a regional system for deployment of plug-in electric vehicle charging stations, each of which obtains power from wind, solar and the grid. The method embodies a two-stage algorithm, the first stage handles system design, and the second stage handles dynamic control under uncertainty. The second stage control problem is embedded within the first stage design problem, thus enabling design for controllability. The solution procedure uses a new, statistically parsimonious algorithm to reduce the computational demands that have previously made this problem intractable.

Intellectual Merit
This research is foundational to energy system development, an area of critical national need. Success in addressing the foundational issues will demonstrate the efficacy of the method for the design and deployment of realistic systems and help identify questions worthy of further investigation.

Broader Impacts
This work has the potential of improving the penetration level of renewable energy and ease or delay the need for infrastructure improvement. Design for controllability is critical for many other complex systems in energy, transportation, telecommunications, sustainability, manufacturing, health care, etc. The team has a track record of educating members of under-represented groups and will continue to do so. Research results will be disseminated via standard academic means and will be shared with Vision North Texas, a public-private partnership seeking a more sustainable future for North Central Texas.