Solar research goes thermal - Researchers have proposed ideas to produce liquid fuels and heat.

www.mndaily.com
02/10/2010

From solar energyed vehicles to solar gasifiers, students and faculty at the University of Minnesota have participated in more than a dozen research projects as part of an effort to develop new methods of using solar energy as a renewable resource. But more recently, researchers have proposed ideas that utilize solar thermal processes to produce liquid fuels and heat.

With several projects funded by the Initiative for Renewable Energy and the Environment and the U.S. Department of Energy, professors and graduate students are collaborating to conduct research that has the potential to assist in making the transition from fossil fuels to clean energy, said mechanical engineering professor Jane Davidson. Davidson serves as the principal investigator for a large number of the research projects.

Currently, solar energy can be acquired through towers, satellite-like dishes and parabolic troughs - large structures that use reflective material like mirrors to absorb solar energy. Several research groups have also been focusing on thermal solar processes to produce energy sources. One group of graduate students, accompanied by professors, are researching ways to collect solar energy, said Luke Venstrom, a graduate student in the Department of Mechanical Engineering.

Mechanical engineering graduate student Brandon Hathaway's area of focus uses solar energy to heat and convert cellulosic biofuel feedstock, like prairie grass, to energy in a gasification process. According to Hathaway, solar energy reduces the amount of feedstock combusted in the process and, in effect, provides a higher quantity of energy that can be used to produce liquid fuels such as synthetic gasoline. Since last summer, University professor Andreas Stein has been working on developing a solar thermal process that involves converting carbon dioxide into carbon monoxide, which could then form liquid fuels such as methanol.

Stein said that because of its stability rate, high temperatures are required to break down carbon dioxide. However, in order to retain the materials used, researchers are attempting to use a metal oxide that will allow the carbon dioxide to be converted at a lower temperature while simultaneously using solar energy. Stein stressed that the efficiency of solar thermal processes is "much higher" than solar electric processes.