Professor of Chemistry, Dr. David Freeman uses theoretical methods to study the thermodynamic properties of hydrogen in clathrate hydrates.

Clathrate hydrates are complex molecular systems that can roughly be described as cages, within which hydrogen can be stored.  When a second Hydrogen can readily be stored in the hydrates up to ~ 4% by weight when a second solute, tetrahydrofuran, is added to the system.

Understanding the role of this co-solute in increasing the hydrogen solubility is critical to further increasing the amount of hydrogen that can be stored.

Experimental studies suggest that the hydrogen molecules can exist in different orientations. The nature and interpretation of the orientational order of the hydrogen molecules and co-solutes is essential to fully understanding the properties of the system. Results from this theoretical work can be used to guide experimentalists in designing new systems that can achieve the goal of 6.5 % by weight hydrogen storage material.

The most abundant energy source on the surface of the earth is the sun. The sun delivers a continuous supply of energy estimated to be 120,000 terawatts (TW); whereas, the current usage of energy by humanity is about 13 TW. The problem with solar energy is that it is diffuse and cyclic, which leads to economic impediments for its use. Hence, a vital and growing area of research is to improve the efficiency of solar energy conversion to meet future needs at economically competitive costs.

Professor of Chemistry and Chair of the Chemistry Department, Dr. William Euler is working with his research team on two approaches for converting sunlight into other forms of usable energy. In a traditional approach, he is developing photovoltaic solar cells that convert sunlight into electricity. Conventional photovoltaic cells are semiconductors, which have good conversion efficiencies but are mechanically brittle and expensive to produce. In contrast, organic photovoltaic cells are flexible and cheap to produce but have low conversion efficiencies. Dr. Euler’s approach is to blend these two extremes. He has prepared organic/inorganic nanocomposites that address both of the aforementioned problems.

His second approach to the solar energy conversion problem is to directly convert light to mechanical energy. A few years ago he discovered a system that responds to exposure to light by bending a significant amount, an effect we termed photo-actuation. The photo-actuators are robust and are able to push 100× their self-mass using light levels less than noon time sun.

Please visit Professor Euler’s website to learn more about his work.

A combination of high gasoline prices and global warming has fueled growing interest in the development of alternative energy sources for automobiles. These economic and ecological factors have stimulated widespread sales of Hybrid Electric Vehicles (HEV) and the development of the Plug-In Hybrid Electric Vehicle (PHEV). The market size for electric vehicles has been estimated at 2.5 million units by 2009 or an excess of $ 1 billion in sales of vehicle batteries.

While lithium-ion batteries (LIB) have the highest energy and power density of any rechargeable battery, commercial LIBs have several problems including, loss of power and capacity upon storage or prolonged use, especially at elevated temperatures. Most HEV and PHEV applications require a LIB life goal of 10 years but those that are currently available only have a calendar life of 3-5 years. In order to develop high energy LIBs for HEV or PHEV applications, the lifetime of lithium-ion batteries must be increased.

Professor of Chemistry and URI Energy Center Co-Director, Dr. Brett Lucht has been studying the mechanisms of power-fade in lithium-ion batteries. These investigations have focused on the reactions between common electrolytes in lithium ion batteries and the surface of the electrode materials. Reactions of the electrolyte with the surface of the electrode materials generate a solid electrolyte interface (SEI on both the anode and cathode). Detailed analysis of the structure of the SEI on both the cathode and anode has allowed a general understanding of the performance-limiting reactions inside of lithium ion batteries. He has also investigated novel additives that inhibit detrimental reaction between the electrolyte and electrode materials and enhance the thermal stability and calendar life of lithium ion batteries.

The utilization of energy crops produced on American farms as a source of renewable fuels is a concept with great relevance to ecological and economic issues on both national and global scales. The development of a significant national capacity to utilize plant cellulose as a renewable source of biofuels could provide independence from foreign oil, a cleaner fuel source for road vehicles, diminish greenhouse gas emissions, benefit our agricultural economy by providing an important new source of income for farmers, and allow for more productive use of land.

There is a broad need for technology development relevant to the genetic improvement of Energy Crop plants, such as switchgrass (Panicum virgatum, L.), that will be used specifically for biofuels. Switchgrass is considered one of the leading candidate crops by the United States Department of Agriculture (USDA) and the Department of Energy (DOE) for large scale cellulosic ethanol production. Genetic improvement of switchgrass will lead to improved production of biofuels, such as ethanol.

Genetic modification of plants has proven to be a highly successful approach to crop trait improvement. This same approach can now be applied to plants that will be used specifically for biofuels production. The opportunities for biofuel crop trait improvement are broad. Among these opportunities is the ability to develop biomass crops with increased yield and traits for improvement of production of cellulosic ethanol. Also, genes for biofuels traits have been designed to improve fuel production and lower costs. However, the possibility of gene flow to wild and nontransgenic plants presents significant challenges to the use of gene modification in perennial biofuels species. A solution to the problem of gene confinement is therefore necessary to the implementation of genetic modification in many plants used for biofuels.

Professors of Cellular and Molecular Biology, Dr. Albert Kausch and Dr. Joel M. Chandlee have developed a strategy for controlled total vegetative growth of switchgrass through down-regulation of a plant gene that determines reproductive transition in combination with herbicide resistance and a site specific DNA recombination system. This strategy for selective floral ablation should result in continuous vegetative growth for increased biomass and also provide a system of gene confinement for prevention of transgene escape. In addition, this system will provide the basis for trait stacking of other characteristics important for utilization of switchgrass as a primary source of plant-based biofuels. They call their work ‘Project Golden Switchgrass’, with the long range objective to develop the varieties that will be grown specifically for biofuel production.

For more information about either Professor Kaush or Chandlee please visit their websites:  Dr. Kaush  Dr. Chandlee

Professors of Ocean Engineering, Dr. Stephan Grilli and Dr. Malcom Spaulding have been interested in wave energy research since the early 1990s, when they visited some of the first wave energy plants installed in Norway. However, it was only in 2001 that they worked on an exploratory research project with Harry Hopfe, of US Wave Energy Inc., who has designed a novel wave energy system based on a float and a submergence plane, connected by hydraulic pistons. The differential wave motion between float and plate actuates the pistons and yields pressure changes in a hydraulic circuit that produces energy. A 1/10th scale model of this device was built and tested in OCE’s wavetank by Dr. Grilli and one of his graduate students. The device was used to provide power to Pacific Island communities.

In 2003-05, Ocean Links, formerly, Energetech Inc. obtained funding through the “RI Renewable Energy Office,” to design and test a 500 kW demonstrator of their new Oscillating Water Tower (OWT) concept, off of Point Judith, RI. Drs. Grilli and Spaulding along with co-workers from OCE, worked on the siting of the OWT powerplant, by studying wave energy exposure, and made predictions of expected power production. In a parallel project, which involved OCE senior students, other aspects, such as geotechnical and structural design, were studied. More recently, in 2005-06, Drs. Grilli and Spaulding and co-workers from OCE, collaborated with Teledyne Scientific and Imaging Inc., on a Defense Advanced Research Projects Agency (DARPA) funded project to design, test, model, optimize, and evaluate the field performance of low-power, point-absorption wave power devices for marine surveillance applications. As part of this project a new concept, based on promising preliminary results on scale models, was proposed combining spar buoys (resonating in heave) and magnet/coil/spring linear oscillators.