Good News for Coal? Condenser Coating Could Reduce Power Plant Emissions
Researchers at the University of Illinois Urbana-Champaign have been testing the effectiveness of a coating for steam condensers that can significantly reduce carbon emissions by improving heat transfer efficiency.
The transition to renewables is ongoing and many impressive innovations are sweeping through the engineering world as society pivots to greener and cleaner sources of energy. One such innovation is fluorinated diamond-like carbon, or F-DLC, a coating for steam condensers that offers promising potential for coal and natural gas power plants because it can limit carbon emissions during the clean energy transition.
Renewable energy sources include wind and solar. Image used courtesy of Pexels
Obstacles Facing Renewable Energy
There will be a significant interim period before we approach anything that looks like a near-total reliance on renewable energy. This interim period might be longer than some want to admit. According to the Columbia Climate School, many significant hurdles are impeding this transition, some of which still have no workable solution in sight. Building out wind and solar infrastructure is important, but those resources are subject to significant variance, perhaps increasingly so as climate change impacts weather patterns.
And just as weather patterns can create obstacles, natural topography not only limits where solar and wind infrastructure can be installed but it also constrains the construction of more pumped storage hydropower (PSH) systems, which depend on specific natural water requirements and topographical conditions. Renewable energy costs are also likely to increase significantly over time which could adversely impact political will for change.
The figure below depicts the necessary benchmarks that must be met if we are to see total clean energy milestones, and that data tells a story far from where we currently are. While we must embrace such challenges with renewed vigor, the engineering community can also create innovations for cleaner fossil fuel use that actually decrease carbon emissions significantly while we work toward renewable energy ideals.
Clean energy projection data. Image used courtesy of Phys.org
New Coating for Steam Condensers
The hydrophobic quality of the F-DLC coating is the key to its functionality. While water will often form a thin film on clean metals, this coating created from F-DLC forces water into droplets. Similar to the coating on a nonstick frying pan, which repels liquids and creates the same phenomenon of many discrete bubbles rather than a shallow sheet of liquid, F-DLC allows heat to be directly transferred through this droplet formation.
Perhaps the distinction between a thin coating of water and water droplets seems immaterial to the casual observer, but there is, in fact, a substantial difference in efficiency that impacts carbon emissions significantly. The result of the direct heat transfer through the water droplets created an overall two percent increase in efficiency, according to researchers at the University of Illinois at Champaign.
Context here is critical for understanding the wider impact. Steam-cycle power plants are responsible for 70 percent of the global electricity supply. Small marginal improvements create significant gains when it comes to reducing carbon footprints worldwide.
The chemical properties of F-DLC. Image used courtesy of Nature Communications
Research by the team at the University of Illinois Urbana-Champaign Abbott Power Plant has confirmed the durability of this coating as well. They tested it for 1,095 days, which is the longest trial they have reported. F-DLC maintained its hydrophobic quality for the entirety of the trial with no significant variation. Such impressive results suggest that industrial applications will be feasible.
A green future powered by renewable energy is the ideal goal in terms of sustainability, but any significant improvements in carbon emission reduction that can be made should be made until that future is realized. F-DLC belongs to this category of temporary but critical innovations that optimize fossil fuel performance while we perfect clean energy infrastructure.