Skip to Content
Uncategorized

Water-Repellent Coating Could Make Power Plants Greener

A startup has created a water-repellent coating that could significantly increase power plants’ efficiency.
November 24, 2014

Applying a novel coating to part of the machinery in power plants could significantly reduce carbon dioxide emissions. Applying it at just one coal plant would reduce yearly emissions as much as taking 4,000 cars off the road, says Kripa Varanasi, a professor of mechanical engineering at MIT who helped develop the new coating, which is being commercialized by a startup called DropWise.

Water vapor condenses on a silicon wafer with a novel coating from the startup DropWise.

The coating improves the efficiency of a key part of a power plant, the steam condenser. In power plants, fuel is burned to produce steam that spins a turbine. As the steam emerges from the turbine, it needs to be cooled down and condensed back into water—doing so creates a suction force that helps spin the turbine.

The coating helps increase that suction force. The condenser is a series of pipes, and when steam hits them, it turns to water. Ordinarily, water builds up on the walls of the pipes and slows down the cooling process. The new coating repels water, keeping it from building up.

Researchers have been attempting to develop such coatings for decades, but existing methods for depositing them—such as spraying—have trouble producing the correct thickness. Depending on the method and material, they were either so thick that they themselves slowed cooling, or too thin to withstand the harsh steam, says Jonathan Boreyko, a Virginia Tech professor and expert on heat transfer, who did not participate in the work.

To get the right thickness, MIT researchers invented a new process that involves flowing two gases past heated filaments. The gases react and form a polymer coating that is “just thin enough to still be much more efficient, but thick enough to be durable,” Boreyko says.

So far the coating technology has been tested only in the lab. DropWise is working on deals to test the technology in power plants. While the technology could help with emissions, the main incentive for power plants to use the technology would likely be fuel savings—power plant operators could save nearly half a million dollars per year.

Keep Reading

Most Popular

Europe's AI Act concept
Europe's AI Act concept

A quick guide to the most important AI law you’ve never heard of

The European Union is planning new legislation aimed at curbing the worst harms associated with artificial intelligence.

Uber Autonomous Vehicles parked in a lot
Uber Autonomous Vehicles parked in a lot

It will soon be easy for self-driving cars to hide in plain sight. We shouldn’t let them.

If they ever hit our roads for real, other drivers need to know exactly what they are.

supermassive black hole at center of Milky Way
supermassive black hole at center of Milky Way

This is the first image of the black hole at the center of our galaxy

The stunning image was made possible by linking eight existing radio observatories across the globe.

transplant surgery
transplant surgery

The gene-edited pig heart given to a dying patient was infected with a pig virus

The first transplant of a genetically-modified pig heart into a human may have ended prematurely because of a well-known—and avoidable—risk.

Stay connected

Illustration by Rose WongIllustration by Rose Wong

Get the latest updates from
MIT Technology Review

Discover special offers, top stories, upcoming events, and more.

Thank you for submitting your email!

Explore more newsletters

It looks like something went wrong.

We’re having trouble saving your preferences. Try refreshing this page and updating them one more time. If you continue to get this message, reach out to us at customer-service@technologyreview.com with a list of newsletters you’d like to receive.