This pinecone-sized device could transform the fight against wildfires

By Oscar Holland, CNN

In the multibillion-dollar global fight against wildfires, early detection is critical. Satellites, drones, thermal cameras and manned lookout towers are just some of the tools currently used to alert authorities and first responders to imminent threats.

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In under-resourced areas, however, these defenses can be prohibitively expensive. That’s why a group of recent design graduates has developed a smaller, simpler and, they say, cheaper solution: A pinecone-sized fire detector that can give vulnerable communities an invaluable head start in the race to escape or contain major blazes.

Made primarily from wax and charcoal composites, Pyri’s sensors are designed to blend in with — and leave no footprint on — the environment. The device can be deployed in fire-prone areas and left for years without maintenance, according to its creators. When a fire occurs, the heat melts an internal trigger, producing a low-frequency signal that raises the alarm.

“It can help people evacuate sooner, and it can stop fires from growing before they’re uncontrollable — before they’re really devastating,” Pyri co-founder Karina Gunadi told CNN in a video interview. “If you can catch a fire small, it’s a lot easier to put out.”

Pyri started in London as a college assignment between four design engineering students, three of whom decided to pursue it as a commercial venture beyond their graduation last year. Their company’s name comes from the scientific word “pyriscence,” which describes the ways nature adapts to wildfires.

As an example of a “fire-dependent species,” Gunadi pointed to various types of pine tree that not only thrive in fire-prone areas — they need blazes to reproduce, as their seeds are only released when the resin sealing their pinecones melts in high heat.

This idea directly influenced Gunadi and her fellow designers. “What if we can be inspired by how nature already responds to fire, take that, use nature-based materials and create the simplest form of wildfire detection we can?” she said, recalling the genesis of the group’s design.

Leave no trace

Designed to blend in with nature, the latest prototype weighs around 150 grams.

Pyri’s pinecone-like appearance is also functional: The lightweight sensors’ shape and ribbed structure helps protect them against impact, especially if deployed from the air when covering large or hard-to reach areas. But the designers also wanted them to escape the attention of passersby, whether human or animal.

“We’ve actually lost one in the environment. So, in terms of camouflage, we’re doing maybe a little too well!” Gunadi joked.

Another major challenge stems from the co-founders’ commitment to non-toxic materials — especially when it comes to the electronics required to produce a signal. Although Pyri is not publicly detailing its trigger technology or disclosing its precise material composition (a patent application is pending), the designers looked to organic electronics and are avoiding rare earth metals and lithium-ion batteries. Once the devices “burn up,” Gunadi wants to ensure they are “not going to leave any negative impact on the environment.”

Extreme wildfires are becoming more frequent globally, with fire seasons now longer, hotter and drier than before. Climate change is a major contributor, as drought and rising global temperatures make the infernos bigger, faster and harder to stop. This, in turn, may worsen the climate crisis. According to the United Nations Environment Programme (UNEP), wildfires were responsible for an estimated 6,687 megatons of carbon dioxide pollution in 2023 — seven times more than was emitted by global aviation that year.

UNEP predicts a 30% increase in extreme fires by the end of 2050 — and a 50% increase by the end of the century. Major blazes are also occurring in places that have not, historically, been considered fire-prone, from America’s eastern seaboard to Siberia, Russia.

The impact of wildfires is, for Pyri’s creators, personal. One of the company’s co-founders, Richard Alexandre, hails from Brazil, where he witnessed first-hand the devastation of forest fires in Pantanal, a region that experienced a record-breaking number of blazes last summer. Gunadi, meanwhile, grew up in Palo Alto, California. She was living in San Francisco during the 2020 North Complex Fire that engulfed the city in smoke.

“I woke up and the sky was dark orange, and it was like that for days,” she recalled. “That was really scary.”

Early detection matters

Pyri’s designers developed the sensors as part of a master’s program jointly run by the UK’s Royal College of Art and Imperial College London.

Wildfires spread at speeds of up to 14 miles per hour, so every minute counts. A 2020 study into early bushfire detection by the Australian National University found that a one-hour reduction in response time could reduce the frequency of large fires by 16%.

Earlier this year, the outgoing Biden-Harris administration earmarked $15 million in funding to construct and deploy a “new suite of fire weather observing systems” in high-risk US locations (though it is unclear what impact, if any, President Donald Trump’s attempts to block funds associated with the bipartisan infrastructure law will have on these programs). Google, meanwhile, recently announced $13 million in funding for its FireSat initiative, which will use a “constellation of satellites” to track fires as small as 5 square meters (54 square feet) using realtime images that refresh every 20 minutes.

Pyri is by no means the only company developing simpler, on-the-ground sensor technology. Since 2019, the US Department of Homeland Security’s Science and Technology Directorate (S&T) has been researching and trialing new wildfire detectors in collaboration with small businesses including Maryland-based N5 Sensors, which says it can detect ignition within five minutes, even if a fire is “only a few square meters in size.”

Traditionally, sensors have relied on optical cameras or thermal imaging that could “see” the flames, but S&T says it hopes its new devices can “sniff” gases or solid particles in the air. It is also using data from earlier trials to inform artificial intelligence algorithms used in its latest sensors.

Pyri’s designers are also looking to artificial intelligence: When one of their devices is triggered, AI can analyze available weather and satellite data to assess the likelihood that the signal was indeed the result of a wildfire.

The number of devices required in any given area will depend greatly on the geography of the site, including topography and vegetation, Gunadi said, adding that “fire dynamics are very complicated.” Pyri is hoping to sell a per-kilometer subscription package that bundle together sensors with installation and monitoring software. Declining to reveal the startup’s future pricing, Gunadi said it is aiming for fees that are “half the cost of our nearest competitor.”

As such, Pyri hopes to target customers with fewer resources — whether that is money, skilled labor, infrastructure or time — to tackle wildfires. It aims to start with the forestry, agriculture and utility sectors in the US, but has fielded queries from around the world.

Since graduating, Pyri’s co-founders have been carrying out research and development and raising funds — including a £5,000 ($6,677) prize from winning a James Dyson Award, an international student design competition founded by the titular British inventor and Dyson founder. The company hopes to run small-scale tests and demonstrations later this year, with a view to operating larger pilots next year and launching commercially in 2027.