Upon receiving the experimental results, Adam Slavney and Jinyoung Seo were left perplexed. They had been examining a new category of materials aimed at enhancing the efficiency of refrigerators, air conditioners, and heat pumps, a quest that the cooling appliance sector has pursued for ages. The readings for the materials under investigation by the team shouldn’t have varied, yet they did.

“What accounts for these differences? What modifications did we implement?” Slavney expressed to TechCrunch. “We had a hint of it within about three months, but it took a year or two to acquire definitive evidence.”

That evidence is now the foundation of Slavney’s startup, Pascal, where he serves as co-founder and CEO alongside Seo, who is co-founder and CTO. The company recently secured $8.5 million in a follow-up to its seed funding round, co-led by Sazze Partners and LB Investment, with contributions from KDB Silicon Valley, which the company disclosed exclusively to TechCrunch.

According to him, a refrigerator or heat pump utilizing Pascal’s material is expected to be approximately 20% more efficient than current models. (Both heat pumps and refrigerators operate on the same fundamental technology.) The startup has inked a deal with a global beverage corporation for a technology pilot.

“This funding round initially came together because we secured a customer contract sooner than anticipated,” Slavney noted. Pascal is set to deliver its first prototype by early next year and aims to follow that up with a more refined batch of refrigerators in 2028.

For nearly as long as refrigerators have been in existence, scientists have been on the lookout for improved refrigerants. More recently, their focus has shifted to finding compounds that don’t adversely affect the atmosphere. Such substances do exist, but they must also match or exceed the effectiveness of current refrigerants.

“For the past 35, 40 years, we’ve been engaged in a game of whack-a-mole with refrigerants,” Slavney remarked. Older gaseous refrigerants like Freon damaged the ozone layer, while newer alternatives like R-134a still serve as extremely potent greenhouse gases. “It’s an unending cycle,” he added.

One alternative that has garnered interest from researchers is a category of materials referred to as solid-state refrigerants. Being solid means they cannot escape into the atmosphere, removing the climate and ozone issues that plague modern refrigerants. Solid-state refrigerants hold the potential to enhance the efficiency of refrigerators and heat pumps. They operate similarly to traditional refrigerants, releasing heat when compressed and absorbing it when that pressure is alleviated.

Prior to his fortunate discovery, Slavney and his team at Harvard University had been investigating these materials. “We aimed to perform some high-pressure measurements, and the apparatus we utilized required gas. We started with one gas, switched to another, and pondered why the results varied,” Slavney explained.

Following numerous further experiments, the team realized they had uncovered an alternative approach to solid-state refrigeration. Instead of compressing a solid block of material, Pascal’s heat pumps pressurize a gas—carbon dioxide—into a cartridge filled with a proprietary sponge-like material, as stated by Slavney.

As carbon dioxide permeates the porous medium, the gas molecules collide with the walls of the pores. These interactions transfer energy to the material, raising its temperature. A heat exchanger then expels some of that heat. Reversing the process allows the material to draw energy from the heat exchanger and transfer it to the carbon dioxide molecules.

In a Pascal refrigerator, two cartridges are operational simultaneously. One absorbs heat from the inside of the refrigerator and transfers it to the carbon dioxide, while the other takes heat from the carbon dioxide and transfers it to the exterior air. Eventually, the cartridges become excessively hot and cold, prompting a reversal of the flow.

“The material is extremely resilient,” Slavney noted. “We’ve cycled it up to 300,000 times. That equates to about a year of operation.”

The entire system transfers heat more efficiently than other solid-state refrigerants, signifying that Pascal does not need to function at the elevated pressures that other solid-state refrigerants might require.

“We’re utilizing conventional systems to achieve this,” Slavney mentioned. “This indicates that we believe we can make it affordable, which allows for broader implementation.”