Four Triad universities are working together on a project to significantly reduce the cost of generating electricity from sunlight.
The Four Universities Solar Consortium is composed of scientists and engineers from North Carolina Agricultural and Technical State University, the University of North Carolina at Greensboro, Wake Forest University, and Winston-Salem State University.
The team’s specific goal is to develop a low-cost solar concentrator that will make the production of electricity from sunlight economically viable and widespread.
To do that, the team will have to advance the science of using concentrated sunlight to split water molecules into hydrogen and oxygen and then develop a way to store the hydrogen on site for capacity leveling. “This further requires developing and integrating, through industrial partnerships, three important supporting technologies for mirrors, waste-heat recovery, and high-temperature photovoltaics and catalytic reactors,” the team’s proposal says.
The project was one of three finalists for a $100,000 grant from the four schools’ Triad Interuniversity Planning Project (TIPP). The provosts of the schools are funding the one-year project. Each finalist previously received a one-year TIPP planning grant of $20,000.
“We were betting in the planning phase that an acre of mirrors could be constructed more cheaply than an acre of efficient photovoltaics, and that the higher temperature of waste heat from concentrator systems will open routes for reclaiming some of it as electricity,” the team said in its proposal.
The solar consortium aims to leapfrog the route of incrementally improving photovoltaics, which are still relatively expensive despite decades of development. “Nature can be pretty unyielding on the basic material parameters when you have already been pushing them to the limit over 40 years,” the consortium states on its website, http://tippsolar.uncg.edu/.
“The movement of different systems and materials into commodity status because of unrelated mass markets seems a softer target. We propose to go after the more yielding territory of making the concentrators less costly, and then use them with proven power conversion technologies in limited area (expense) at the concentrator foci.”
The researchers are working with two Triad companies, 3A Composites of Colfax and Slane Marine in High Point, as well as 3M Corp. They also are in discussions with Cool Energy Inc. of Boulder, Colorado.
Among the power conversion technologies to be evaluated are double- or triple-junction photovoltaic cells cascaded with thermoelectric converters for combined efficiency up to 50% in a concentrator application. A second technology is the use of Stirling engines with efficiency of 32% or higher. A third is thermal electrolysis and/or photocatalysis to generate hydrogen and fixed-site storage and use of fuel cells for off-daylight and load-leveling capability. A fourth will be a research investigation on novel gallium arsenide nanowires for solar cell applications.
The first of the four conversion systems (photovoltaic/thermoelectric) is already available and could become affordable when divided among multiple mirror modules.
“This project will go all the way to experimental testing of a single mirror module and documentation of its performance, along with preliminary demonstration of electric power generation,” the website states. “Preliminary assessments of business viability and of environmental impact were started in the planning year and will be expanded in the second year.”
Research won’t be team’s only mission.
“Education is very important in this project, both to give the public a means of honestly deciding on their crucial acceptance of the technology and to give students of the four institutions (and beyond through distance learning) a chance to follow and develop a concept from science through engineering to environmental, business, and public policy aspects,” the consortium states.
The team is evaluating plans to build a 3-meter-diameter concentrator dish system and test versions of power conversion units for productivity, maintenance, and reliability. The system will be demonstrated for the public, potential utility partners, venture capital investors, and federal agencies.
The faculty members on the team are:
- From N.C. A&T and the Joint School of Nanoscience and Nanoengineering: Dr. Shanthi Iyer, Department of Electrical and Computer Engineering (A&T) and Department of Nanoengineering (JSNN).
- From the University of North Carolina at Greensboro: Dr. Liam Duffy, Department of Chemistry and Biochemistry, and Dr. Ray Purdom, Director, Lilly Conference on College and University Teaching in Greensboro.
- From Wake Forest University: Dr. Richard Williams, Department of Physics; Dr. Keerthi Senevirathne, WFU Center for Energy, Environment, and Sustainability; Dr. David Carroll, WFU Center for Nanotechnology and Molecular Materials; Dr. Abdou Lachgar, Department of Chemistry.
- From Winston-Salem State University: Dr. Lei Zhang, Department of Chemistry, and Mr. Wyndham Wilkinson, Plastics Manufacturing Consultant.