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Chilled, No Ice

Stanford grad rethinks the cold chain.
Long-haul trucks are one link in the chain for transporting refrigerated goods. Photo: Unsplash | Ivan Bandura /

Cold-chain shipping is the modern miracle that brings highly perishable crops like spinach and strawberries to your kitchen table from across the country—or even around the world. It’s also what shuttles temperature-critical medicines safely from place to place.

Hannah Sieber

“It’s this invisible backbone that no one thinks or talks about, but it powers so much of our economy,”  says Hannah Sieber, MS/MBA ’22, CEO and cofounder of Artyc, a startup with a fresh take on cold shipping.

Globally the cold-chain market was valued at more than $300 billion in 2022, on pace to nearly triple by the year 2030 - an industry already responsible for an estimated 4 percent of total greenhouse gases.

“If we can make even a small dent in emissions, that’s a huge dent broadly—and I think we’re just at the beginning,” she says.

Chilling entire cargo ships and warehouse distribution centers consumes a lot of electricity, and it requires refrigerants, which are potent greenhouse gases. For instance, the commonly used refrigerant HFC 134-A, known by its trademarked name as Freon, has a global warming potential factor over 1,000 times greater than carbon dioxide.

Cold chain today also produces a vast mountain of styrofoam and single-use frozen gel packs. (One distributor client confessed to using 10 million pounds of styrofoam in a year.)

And it’s a system that can easily break down.

Sieber learned from her market research interviews during graduate school that spoilage tends to happen at the handoffs in the cold-chain system, from farm to long-haul truck, or cold room to airplane, or anywhere in the relay race to get a refrigerated product to its final destination, in time and intact, whether that’s a hospital, laboratory, restaurant, or your front porch. Any unexpected weather or overpacked freight can be fraught with consequences.

According to the United Nations’ Sustainable Food Cold Chains Report, an estimated 12 percent of the food grown globally is lost due to a lack of effective refrigeration—enough to feed 1 billion people. In healthcare, the World Health Organization estimates that up to half of vaccines are wasted globally every year, in part due to lack of temperature control.

The more she learned, the more Sieber wondered if cold-chain could go “infrastructure-less,” and if it could be done in a more environmentally responsible way.

Together with her cofounder and CTO, Mark Langer, and a growing team of 15 employees based in Fremont, Calif., that is Artyc’s mission: To produce refrigerant-free, battery-powered cooling for the cold chain.

Redistributing power

Sieber knows a thing or two about rechargeable batteries. She is a serial entrepreneur who for 2 years lived in Shenzhen, China, where 90 percent of the world’s electronics are manufactured. In 2016 she and three colleagues co-founded EcoFlow, a company that sells portable power stations—the battery-powered equivalent to a diesel fuel generator, in order to facilitate off-grid living, or simply having a cleaner source of backup power.

In fall 2019, she enrolled in a joint degree with Stanford Graduate School of Business and the Emmett Interdisciplinary Program in Environment and Resources (E-IPER), in hopes of sharpening her skills and learning more about the sustainable energy transition, from direct air capture to hydrogen fuel cells.

“Stanford is an incredible ecosystem and I feel grateful to have met all the folks across campus,” she says. “I was super interested in battery applications more broadly and particularly around distributed energy resources.”

By 2020, her curiosity had only intensified. By then her classes had moved online in those early pandemic days. Her electricity kept cutting out in the heat of the summer and early fall in the Oakland foothills, spoiling the milk in her fridge and interrupting her classwork, a frustrating experience that ended up sparking her master’s thesis (Quantifying the Economic & Equity Impacts of California’s Planned Safety Power Shut-offs).

Meanwhile, she had a family member who was enrolled in a clinical trial, and she witnessed for the first time the challenges of delivering temperature-sensitive medicines to patients at home. This experience was informative for early product development.

“There are so many tailwinds in our favor,” she says, pointing to the driving need for effective cold-chain shipping for pharmaceutical companies of mRNA vaccines, as well as clinical trials and other medical products. Even on the grocery side, Gallup reported that in 2022, more than one-quarter of households ordered groceries for pickup or delivery at least once a month.

“So there’s this increasing trend toward how do you extend cold chain, not only from middle-mile logistics, but all the way to last-mile logistics?”

Shaken (and stirred)

Artyc’s innovation lies in the cooling algorithms and systems that allow a unit to last up to 56 hours on one battery charge, with a temperature fluctuation of less than 3 degrees Celsius. The batteries themselves are standard lithium-ion.

Tough and jostle-proof, dependable and trackable, the units in Artyc’s initial product line are built to be resilient for modern-day logistics, what Sieber mildly calls “a highly kinetic environment.” They look like durable ice chests, in sizes ranging from a 5-liter to a 25-liter capacity.

The MedStow Mini is Artyc’s first battery-powered cooler, designed for clients in the mobile phlebotomy market. It has room to store up to four vials of samples.

She says most of their early clients have signed on for the live insights on shipment temperature and location, and their hopes for less spoilage and a chance to better optimize shipping logistics. The climate benefits? That’s an added bonus.

“We’re big believers that you can’t expect customers to pay a green premium,” she says. “Most of our customers don’t find us because they’re looking for a more sustainable product. They find us because they’re really excited about the active cooling technology we’re building.”

In 2022, Artyc received an Innovation Transfer Grant from the TomKat Center that the founding team used for market research, leading the venture to focus first on healthcare, specifically on supporting decentralized clinical trials. Later products will target agriculture and food companies.

“We did a ton of customer discovery, and that helped us to really get into the nitty-gritty of segmenting willingness to pay, and of who the right buyer was.”

Though their first product is tailored, Artyc’s vision is global.

Sieber sees Artyc as a systems solution—to slowing climate change, yes, but also to delivering greater health equity and food justice. They hope to enable small-scale farmers to reap a greater profit for their produce, to feed the hungry, and to bring medicine to the most rural corners of the continents.

“I would love to see us really extend and change the game for what it means to have access to fresh produce and vaccines, all around the globe,” she says.


This article is part of the TomKat Center Spotlight series designed to highlight the impact and trajectory of the work of faculty and students who received funding through our Innovation Transfer Program, TomKat Solutions, and Graduate Fellowships. Stanford University does not endorse any non-Stanford entities, programs, products, or services listed in the article.