Fighting Fire with Sound Waves with Sonic FireTech’s Geoff Bruder

Geoff Bruder is the co-founder and CEO of Sonic Fire Tech, a company developing acoustic fire suppression systems that use sound waves to extinguish flames.

What is Sonic Fire Tech?
We’re suppressing fire with sound waves. What I like to tell people is we’re changing the paradigm on how fire is approached to be proactive rather than reactive. Every existing fire suppression technique basically waits until they’re very sure there’s a fire before triggering. That’s because these systems destroy everything. They’re either drenching everything with water, spraying chemicals, or if you’re looking at something like a data center, they’ve gone back to using displaced oxygen. So they’re pumping in nitrogen and making it so the oxygen levels are too low for fire to exist. But people can’t exist either, so they’re extremely dangerous. Because there’s no side effect to our system, we can use the most sensitive detectors around and trigger within milliseconds of a spark to make sure that a fire can’t grow.

What led you to found Sonic Fire Tech?

My co-founder Michael Thomas had been working on something adjacent to this. He’s a lawyer with no engineering degree, but very ambitious and stubborn. He was looking at a drone that could dive into wildfires and fight them from inside. He was using parallel pressure waves. He got to a point where he needed some technical help and started doing some Googling. He found patents that I had published while at NASA and reached out to me on LinkedIn. He said, “Hey, I’m thinking about doing this. What do you think?” We ended up linking up and starting the company shortly thereafter. I ended up in the CEO role just by happenstance. I’m much more comfortable in the lab building stuff.

How did your NASA background prepare you for this technology?

My background at NASA was working on power systems for planetary missions. Have you ever seen the movie “The Martian”? If you recall, Matt Damon pulls this white box out of the ground at one point and it keeps him warm in the rover. He pulls it out because it’s got plutonium in it. That box is called the MMRTG, the Multi-Mission Radioisotope Thermoelectric Generator. I was working on the replacement for that, which used Stirling engines to make a more efficient version.

Then I ended up working on a Venus mission where that box wouldn’t survive. We needed something simpler. I came up with a new architecture that converted heat energy into high-intensity acoustic waves. Those waves could then be converted into usable power and cooling for a lander. We were trying to survive one Venus day, which is 243 Earth days. The Soviet Venera lander’s titanium ball melted in just 127 minutes on that surface.

I patented that and licensed it to a group out of Silicon Valley. I left NASA to help them commercialize it. In the process of making power systems that used acoustic waves internally, I was building high-intensity, high-efficiency acoustic systems for the past 15 years or so.

Others have tried acoustic fire suppression before. What’s different about your approach?

DARPA and two students from George Mason University who formed a company called Force SV are the notable folks who tried this before. They were both using subwoofers. Subwoofers are much less than 1% efficient. If you hear a car going down the street with the trunk rattling, they’re throwing thousands of electrical watts to get maybe a single acoustic watt out of that.

In the engines I was working on at NASA, we needed to create and receive acoustic waves. That was the biggest loss in the system, so we needed to operate at 80% to 90% efficiency. The first pass I took at this, I bought parts from Home Depot and AutoZone along with a high-end subwoofer. I did a lot of the tricks I knew to force efficiency and was able to put a fire out from seven feet away. The furthest we had seen anybody do it before was about 18 inches. We melted the speaker in a couple of minutes, but showed that it was possible.