ORNL research to boost concentrating solar power collector, receiver performance

In a push to lower the cost of solar power, the Department of Energy has funded two projects at Oak Ridge National Laboratory focused on improving concentrating solar power collector and receiver performance.

A team headed by Scott Hunter of ORNL's Nanosystems and Structures group in the Measurement Science and Systems Engineering Division was awarded more than $2 million by the Energy Department's SunShot Initiative Concentrating Solar Power program for a project titled "Low-cost self-cleaning reflector coatings for concentrating solar power collectors." The project aims to develop a transparent superhydrophobic coating that can be applied to the surface of solar collector mirrors. The coating will help keep the collector mirrors clear of debris by preventing dust from sticking to the mirror surface, maximizing the amount of reflected sunlight from the collector mirrors while decreasing cleaning costs.

"By using transparent superhydrophobic coatings on collector mirrors we can create high performance and low maintenance concentrating solar power electricity generation," Hunter said.

Most of these electricity generation facilities are located in the semi-arid and arid regions of the Southwestern US, where airborne sand and dust are prevalent and clean water is scarce. The facilities typically contain several hundred thousand mirrors that must be washed and scrubbed on a weekly basis with expensive deionized water.

The ORNL-developed reflector coatings could offer up to a 90 per cent reduction in mirror cleaning and maintenance costs while providing up to 20 per cent improvement in the average amount of reflected solar energy.

A second grant for $450,000 was awarded to the University of Colorado and the National Renewable Energy Laboratory. Using tools available through the Oak Ridge Leadership Computing Facility, the project will employ ORNL's expertise in high performance computing and computational granular flows to study high-temperature, inexpensive granular materials for concentrating solar power technologies. Sreekanth Pannala is the lead ORNL researcher.

The SunShot Initiative that is funding the BRIDGE collaboration is part of DOE's Office of Energy Efficiency and Renewable Energy, and the Oak Ridge Leadership Computing Facility is funded by the Advanced Scientific Computing Research program office within DOE's Office of Science.