Materials Research

EPA Grant Number: X83254101-0

Center: CEER at Alfred University

Investigators: Carty, William and Edwards, Doreen

Institution: Alfred University

Project Period:  September 1, 2005 – June 1, 2006

Research Category: Congressionally Mandated Center

 

 

Description:

 

Objectives/Hypotheses:

Sulfur dioxide (SO2) and nitrogen oxides (NOx) are the primary causes of acid rain.  In the United States, approximately two-thirds of all SO2 and a quarter of all NOx result from the burning of fossil fuels to produce electrical power.  The production of electricity using solar energy is an attractive (clean) alternative to burning fossil fuels.  However, the cost of solar energy must be competitive with that produced by combustion processes for it to be widely used.  The collector tubes used in current concentrating solar power (CSP) trough plants are prone to failure, which represents the single largest performance impact and operation and maintenance costs.  This project concerns the development of a ceramic coating that can be used to refurbish (recycle) failed collector tubes and to manufacture new tubes so as to circumvent many of the problems found in the current tubes.  The project will investigate the effects of coating composition and processing variables on the optical performance of the coatings.  Large-scale deposition methods will be evaluated so that the developed coatings can be applied to actual tubes that will ultimately be field tested. 

 

The results of this study have the potential to reduce the cost of solar-derived electricity and remove failed collector tubes from the waste stream.

 

Approach:

We proposed to develop a coating system that reduces or eliminates the need for maintaining a vacuum, which would reduce or virtually circumvent many of the problems currently encountered in solar power collection arrays.  The coating technology would not only enable the recycling of failed Mo-coated tubes, but may also be used in the manufacture of new, more robust tubes.  The proposed technology could potentially greatly expand the ability to harvest solar energy and could substantially reduce the long-term operating costs of the current facilities, making them a more attractive alternative to other, more polluting technologies.  

 

The technical objectives of this proposal are to develop and characterize robust spectrally-selective oxide coatings that can be applied to the refurbished stainless-steel tubes.  The proposed coatings will be based on a family of matte-finish black enamel coatings that were recently developed at Alfred University for ceramic-glaze applications.

 

This project will have four tasks as follows:

Task 1.  Develop and characterize coated test samples (screening experiments) 

Task 2.  Apply and evaluate coatings on curved substrates

Task 3.  Evaluate feasibility, both economical and technological, for commercial application.

Task 4.  Thesis and Reporting

 

Expected Results:

Ceramic coatings with high durability (thermally, mechanically, and chemically) will be developed and tested on a lab scale.   Through the analysis of these materials, optimized coatings will be developed and applied to curved stainless steel substrates.  Larger-scale coating processes will be evaluated.  Eventually, the coatings will be field tested and could potentially be used as a cost effective means of refurbishing solar power collection tubes or in manufacturing new, more robust collection tubes.

 

The technology may also be well suited for domestic and commercial solar hot water heating systems.  The environmental benefits of the proposed work are 1) recycling of failed collector tubes and 2) the development of enabling technology for the large-scale production of electricity using solar energy.  The use of solar energy instead of fossil-fuels to produce electricity will result in a decrease in the emission of SO2, NOx, and CO2.  In the case of coal-derived electricity, the average emission rates of these gases are 13 lb/MWh of SO2, 6lbs/MWh of NOx, and 2,249 lb/MWh of CO2 (U.S. EPA, eGRID 2000).  

 

 

Supplemental Keywords:

Solar energy, technology for a sustainable environment, clean technology, recycled materials