List of Participants
The participants are a multidisciplinary team of faculty at the University of Hawaii Manoa from the Colleges of Engineering, Social Sciences, Natural Sciences, and the School of Ocean and Earth Science and Technology.
Participants / Education Areas / Research ThemesPI / Dept. / DMM / Sys / PC / Sus / REPS / IRE / SG / EnE / App
Anthony Kuh / EE / X / X / X
CoPIs
David Garmire / EE
Mehrdad Ghasemi Nejhad / ME
Reza Gorbani / ME
Farshad Rajabipour / CEE
Senior Personnel
Gurdal Arslan / EE
Olga Boric-Lubecke / EE
Beei-Huan Chao / ME
Makena Coffman / URP
Philip Johnson / ICS
Alek Kavcic / EE
Denise Konan / ECON
Eric Miller / HNEI
Aaron Ohta / EE
Panos Prevedouros / CEE
Weilin Qu / ME
Rick Rocheleau / HNEI
Jim Roumasset / ECON
Michelle Teng / CEE
Nori Tarui / ECON
Table 1: RE – Renewable Energy, CEE – Civil and Environmental Engineering, ECON – Economics, EE – Electrical Engineering, HNEI – Hawaii Natural Energy Institute, ICS – Information and Computer Science, ME Mechanical Engineering, URP – Urban and Regional Planning, DMM – RE Devices, Materials, and Manufacturing, Sys – RE Systems and Integration, PC – RE Principles and Conversions, RE Sustainability, REPS – RE Production and Storage, IRE – Grid Integration, SG – Smart Grid, EnE – Energy Efficiency, App – Applications
Vision, Goals, and Thematic Basis
Hawaii provides a unique environment to promote clean energy, energy efficiency, and island sustainability. Hawaii also has a closed energy system that can be studied and analyzed. The United States, Europe, and Asia have much more complex power systems that are much more difficult to study and analyze. The Hawaii power system will be changing in the next several years as we rely on more renewable energy sources, promote energy efficiency, develop a smart power grid, and eventually connect different islands together via undersea power cables. As an example wind farms are being proposed for development on Lanai. Power generated from the wind will be transported via undersea power cables to the population center of Hawaii, Oahu. Hawaii will serve as a laboratory where we can study renewable energy storage systems and transport, a smart Hawaii power grid, integration of renewable sources to the grid, energy efficiency, and applications of renewable energy to island sustainability.
On January 31, 2008 Governor Linda Lingle from Hawaii signed a Memorandum of Understanding (MOU) with the US Department of Energy for the Hawaii – DOE Clean Energy Initiative (HCEI) [2]. Hawaii predominantly relies on fossil fuels to supply its current energy needs. The principle source is from oil from tankers. However, Hawaii has a natural environment with abundant resources including wind, solar, wave, and geothermal that allows for the development of renewable energy sources. The HCEI sets a goal of 70% of total energy production in Hawaii will come from renewable energy by 2030.
In order to achieve these goals we must have an educated workforce to meet the complex challenges necessary to solve the difficult engineering, science, economic, and social problems that will be encountered. The University of Hawaii’s College of Engineering in conjunction with the Hawaii Natural Energy Institute, the Department of Economics, the Department of Urban Planning, and the School of Architecture propose a multidisciplinary integrated education and research program in renewable energy and island sustainability. Faculty on this proposal will work with their Ph.D. students and local Hawaiian utility and energy companies to develop projects in assisting Hawaii in achieving more energy independence, development and integration of more clean energy alternatives, and using clean energy to promote island sustainability. Special attention will be made to recruit underrepresented groups in science and engineering as Ph.D. students.
Major Research Efforts
The state of Hawaii in 2005 had a population of about 1.275 million with about 905,000 living in Oahu [3]. Energy consumption in Hawaii in 2005 was 10,539 million kWh which was 0.3% of the United States total with 5% coming from renewable sources and 95% coming from fossil fuels [4]. The average annual increase in Hawaii electricity consumption was 2% per year for the years between 1980 and 2005 [4]. Figures for 2007 are similar to 2005 percentages with just under 94% coming from fossil fuels and slight more than 5% coming from renewable energy sources [5]. Meeting the HCEI’s goal of 70% coming from energy efficiency and renewable energy sources by 2030 presents enormous technical and economic challenges. The big island of Hawaii already has a substantial generation of power from wind and geothermal sources, however the population center in Oahu has a much smaller percentage of power generated from renewable energy sources.
Hawaii has some unique advantages to be able to meet the challenges from HCEI. They include Hawaii being blessed with a unique environment with abundant resources that can be used to generate clean energy. Hawaii’s power grid is very small compared to the mainland United States and Europe. This allows researchers to study and analyze the grid as more renewable energy sources are integrated into Hawaii’s power grid and a smart grid is developed. The University of Hawaii at Manoa (UHM) is well positioned to assist the state of Hawaii in helping with the HCEI. The College of Engineering (COE) has listed one of its major thrusts in the sustainability area and held a retreat on Jan. 9, 2009 to discuss issues associated with sustainability. We have also hired several new faculty that conduct research and education in renewable energy and sustainability. The Hawaii Natural Energy Institute (HNEI) has been a leading player in energy research and has substantial research efforts in many different renewable energy areas. UHM also has researchers in Economics, Urban and Regional Planning, and Information and Computer Science (ICS) interested in renewable energy and sustainability research and education.
At the UHM we have formed a multidisciplinary team from the COE, HNEI, Economics, Urban and Regional Planning, and ICS to develop an interdisciplinary integrated graduate education and research program in renewable energy and island sustainability. The team has a distinguished research and education background in renewable energy and sustainability having received extensive funding from NSF, DOE, and DOD. Team members have also received University and College teaching awards. From the expertise of our team and the needs of the state of Hawaii we have identified five major research thrusts with each effort being multidisciplinary and closely related to the other areas. Fig. 1 shows a diagram of the five major research thrusts.
Fig. 1 Research Themes
We view Hawaii as a laboratory where we can study the above research themes. Since the power system is closed and relatively small we can obtain a better understanding of renewable energy sources, their integration to the power grid, development of a smart power grid, development of energy efficient practices, and application of renewable energy sources to island sustainability. Details of research projects are presented below.
1) Renewable Energy Production and Storage
In the research projects explained in this section, we take advantage of various resources of Renewable Energy (RE) in Hawaii, such as wind, wave, solar, water, and biofuels and develop REPS devices with improved performances and efficiencies, employing the expertise of our faculty at the University of Hawaii at Manoa (UHM), to make REs viable alternatives to fossil fuel. For the RE Production, we will embark on projects such as: Wind Energy Prediction & Material, where augmented complex LMS algorithm with new machine learning methods using nonlinear complex kernel methods will be employed to accurately predict wind speed and energy. We will also study sensorless methods and inverse modeling as well as machine learning tools, such as echo state networks, and adaptive signal processing and machine learning for short, medium, and long term wind prediction for smooth and efficient operation of wind turbines and wind farms. Wave Energy Production & Material, where wave energy resources in Hawaii will be analyzed and quantified. Also, wave tank experiments will be conducted to develop wave focusing devices and energy extracting system with higher efficiency. Also, we will develop nanocomposites for Wave Rotors to make them lighter, stronger, with better damping. In addition, a universal buoy system for Wave Energy Extraction Farm (WEEF) will be developed and optimized to harvest the wave energy adaptively and efficiently. The environmental and social aspects of WEEP in Hawaii will also be studied. Novel Nanostructured Polymer Fuel Cells, where we will develop: 1) gas diffusion layers (cathodes anodes), made of Carbon Nanotubes (CNTs) with high performance and hydrophobicity; 2) catalyst layers, made of CNTs with in-situ platinum nanoparticles creation and dispersion, that have high-performance and hydrophobicity with lower platinum; 3) proton exchange membrane (PEM), i.e., the electrolyte polymer, with three different substructures: a top dense skin mechanical layer, an in-situ generated middle nano/micro porous layer, and finally a bottom “transporter” gutter layer, to develop fuel cells with higher efficiency, durability, and temperature performance, as well as lower fuel cross-over and cross-over contaminations, with lower humidity requirements, using either hydrogen or methanol (biofuel), with lower costs. Novel Nanostructured Solar Cells, where novel, hybrid polymer, light-weight, high-performance, high efficiency, high temperature applications, and durable “third generation photovoltaic” nanostructured solar cells, will be developed employing nanotechnology. First a CNT based photogeneration and charge carrier system will be developed and evaluated. Second, a hybrid polymer technique, where a novel blended material will be developed that can absorb the light radiation in red and IR region of the spectrum with top electrodes coated with a transparent but harder material to extend the life time in harsh environment. Energy Harvesting Devices, where thermoelectric energy scavengers will be developed to generate power more readily than piezoelectric devices, in the microscale regime. The aspect ratio of the thermoelectric elements will be maximized, along with the density of thermocouple elements in the device to create efficient thermoelectric generators, employing microfabrication processes. These devices can supplement existing power sources wherever temperature gradients exist, and compact light systems are required. For the RE Storage, we will embark on projects such as: Nanostructured Lithium Ion Batteries, where the properties, efficiencies, performance, and energy density of the batteries will be improved while reducing their size and weight by improving on the materials used for anode and the polymer electrolyte, using nanotechnology. For the anode, we grow carbon nanotubes on catalyst particles of silicon using chemical vapor deposition. Also, nanostructured Si wires (that behave differently from Si) will be grown on graphene sheets. For the polymer electrolyte, we will develop a novel flexible nanostructured composite membrane that will have open shell porous microstructures with in-situ generated inorganic nanoparticles and fillers that provide additional thermoxidative stability along with low glass transition temperature, while improving the wear resistant, dielectric constant, mechanical properties, electrochemical stability, ionic conductivity, porosity, and thermal stability with low glass transition temperature. Nanostructured Electrochemical Double-Layer Ultra-Capacitors, where we use CNTs (in place of the activated carbon) with relatively regular pores and higher surface area to provide significantly increased storage capacity. In addition, a nanostructured polymeric film/layer will be developed employing a sol-gel process with incorporate ionic materials. Such polymer layer could remain in semi-gel stage to provide better contact among various components. Mechanical properties and internal free volume in the polymer layer can be increased by blending/alloying the material with a relatively flexible amorphous polymer or plasticizers.
2) Integrating Renewable Energy Sources to Power Grid
The main issue of integrating renewable energy sources into the power grid is that the energy sources are available only some of the time. Sunlight is only available during daytime which varies from 13h:25m:56s during the summer equinox and 10h:50m:11s during the winter solstice. Wave energy is only available during high wave times such as during storms – there is fairly little tidal energy in Hawaii. Wind energy is mainly available when the trade winds are blowing. Varying locations on the Hawaiian Islands will have wind at varying times, intensities, and durations. Geothermal energy is available constantly but only on the big island. Ideally energy can be stored when it is not needed and discharged at times when it is needed.
Apart from optimization techniques for handling varying loads as they are placed on the power grid (which will be covered in the next section), different methods can be used to predict the power available for a particular renewable energy source at a particular time. Most of these methods boil down to having small sensor networks measure availability of the resource in the surrounding area and allow time for the energy harvesters to re-gear for optimal efficiency. Similarly within an array of energy harvesters, smart approaches can be taken to offloading the harvested energy to storage systems or onto the grid depending on availability and distribution of energy across the harvesting array. Examples of useful types of devices that we will research for the grid-integration problem include microelectromechanical systems (MEMS) such as encapsulated accelerometers with self-contained energy scavenging power systems for monitoring wave-energy availability, accurate anemometers for monitoring wind-energy, and microtorsional scanners for lower-power communication in longer distance wireless sensor networks. For the power maintenance aspect of the problem, MEMS devices can also play a part in fast low-power high-current switches and small power storage systems that can withstand many power cycles which is necessary due to the highly fluctuating nature of renewable energy. Materials and packaging techniques for microsensors will also be explored that can sustain long-term operation in a corrosive environment.
3) Smart Grid
A smart grid uses communications, networks, control theory, and computer technology to intelligently control the power grid subject to
1) Load variation
2) Supply variation
3) Disruptions and failures due to natural and man-made causes
4) Usage pattern variation
A smart grid is a grid that optimizes its operation in accordance to changing conditions. Hence, a smart grid is not just a power delivery system. It is a network of sensors, decision devices, power gates, delay operators. In some way, a smart grid resembles the data flow in a computer network. It should have the capability to detect and avert bottlenecks, distribute usage evenly throughout a given time period (day, week, month, season). It should have the capability to “learn” the pattern of usage of every user, to detect the need for extra lighting, or cooling. In a simple and trivial example, there is no point in cooling an office space if no one is in the office. To achieve this, the network must rely on integrated sensing, communication and decision making. In our research particular emphasis will be given to the Hawaii smart grid by applying research from signal processing, communications, networks, control theory, optimization, and embedded systems.