A small, flexible cooling device developed by UCLA scientists can continuously reduce surrounding temperatures by up to 16°F, offering a sustainable alternative to traditional air conditioning.
A Compact, Solid-State Breakthrough in Cooling
Researchers at UCLA have unveiled a new cooling technology that operates without refrigerants, fans or compressors. Instead, it uses layers of flexible polymer films that expand and contract in response to an electric field, thereby actively removing heat. The tiny device, just under an inch wide and a quarter of an inch thick, offers a lightweight, energy-efficient alternative to conventional systems, and has already demonstrated the ability to lower ambient temperatures by nearly 9°C (16°F) continuously in lab tests.
Uses The ‘Electrocaloric Effect’
The prototype uses the electrocaloric effect, which is a property found in certain materials that causes them to change temperature when exposed to an electric field. However, this project has gone further than earlier experiments by pairing this effect with electrostrictive motion, i.e. the polymer also physically moves when charged, allowing the researchers to create a dynamic pumping action that shifts heat away from the source.
Designed With Wearables and Portables in Mind
The lead developer, Professor Qibing Pei of the UCLA Samueli School of Engineering, described the innovation as “a self-regenerative heat pump” and believes it could be ideal for wearable cooling systems. “Coping with heat is becoming a critical health issue,” he said, citing the growing dangers of heat stress in both industrial and consumer contexts. “We need multiple strategies to address it.”
The UCLA team sees wide potential for the design in personal cooling accessories, flexible electronics, and mobile systems used in hot environments. The films are flexible, lightweight, and made without liquid coolant or moving parts, which means they could be incorporated into garments, safety gear, or on-the-go electronic equipment where heat management is essential.
For example, warehouse and outdoor logistics workers in hot climates could benefit from clothing-integrated cooling components. Also, remote field technicians or engineers working on battery-heavy devices in poorly ventilated spaces could also deploy portable cooling pads to protect both personnel and electronics.
A Re-think of How Cooling Systems Are Built
Traditional cooling systems rely on vapour compression, a process that typically uses refrigerants such as hydrofluorocarbons (HFCs). These are powerful greenhouse gases, and while the Kigali Amendment and other measures have helped phase them down, their use remains widespread. Vapour-compression cooling is also relatively mechanically complex, energy-intensive, and bulky.
By contrast, UCLA’s design eliminates the need for refrigerants entirely. Each layer in the stack is coated with carbon nanotubes and acts both as a charge carrier and a heat exchanger. As an electric field is applied, alternating pairs of layers compress and expand in sequence, creating a kind of mechanical ‘accordion’ that actively moves heat from the source through the material and out into the environment.
Hanxiang Wu, one of the paper’s co-lead authors and a postdoctoral scholar in Pei’s lab, explained that the device’s core advantage is its simplicity. “The polymer films use a circuit to shuttle charges between pairs of stacked layers,” he said. “This makes the flexible cooling device more efficient than air conditioners and removes the need for bulky heat sinks or refrigerants.”
Sustainability Advantages for the Built Environment
For commercial and industrial sectors, the implications of this development could be significant. While the current model is small-scale, the underlying principle could enable more energy-efficient climate control in buildings and vehicles if adapted into broader system designs.
For example, smaller commercial premises, off-grid cabins, or remote infrastructure hubs could use scaled-up polymer-based systems to passively remove heat without heavy energy use. Similarly, businesses looking to reduce their cooling-related carbon footprint could integrate such systems into server racks, battery storage units, or sensitive workspaces where localised heat management is critical.
Unlike passive radiative cooling materials, which typically require exposure to the open sky and only work under certain conditions, this system functions independently of ambient humidity, weather, or sunlight. Its electricity-only operation means that when powered by renewables, the cooling process can be entirely emissions-free.
Markets and Use Cases with the Most to Gain
While mainstream residential HVAC systems are unlikely to be replaced overnight, sectors requiring portable, distributed, or wearable cooling solutions may see faster uptake. This includes defence, first responders, sports performance, outdoor event staffing, and high-temperature industrial roles such as glass or steel manufacturing.
The research team has already filed a patent and is exploring future product development. Pei confirmed the device could also be adapted to cool flexible electronics and embedded sensors. In particular, industries working on wearable tech, soft robotics, and thermal regulation in electric vehicles may find these materials offer a compact and scalable solution.
The innovation also opens the door to new kinds of thermal design for electronics. For example, temperature-sensitive components such as lithium batteries, processors, or optical sensors could benefit from localised solid-state cooling that does not compromise device flexibility or mobility.
Still in the Early Stages
Despite the promise, this technology is still in its early stages and, as with many materials science innovations, scaling up from lab to market presents challenges. Currently, the temperature drop of 8.8°C below ambient was achieved under carefully controlled test conditions and for small surface areas.
However, maintaining this level of performance over larger spaces, longer durations, or in real-world outdoor environments will require further development, particularly around durability, power consumption, and integration with fabrics or casings.
Another limitation is cost. While the polymers and carbon nanotubes used are relatively accessible, mass-manufacturing precision-layered ferroelectric film stacks could prove complex and expensive without production breakthroughs. Reliability under repeated use and extreme conditions is another consideration, especially for use in wearables or industrial settings.
Energy consumption is also an issue that really matters. For example, while the device itself uses low-voltage electricity, constant operation across large areas would still draw power, meaning the overall carbon footprint depends on the source of that electricity.
Concerns have also been raised in the wider field about the longevity of electrocaloric materials under stress. For example, ferroelectric polymers can degrade over time, especially under high cycling rates, and the cumulative effects of charge and discharge cycling on mechanical integrity are not yet fully known.
What Does This Mean For Your Organisation?
For now, the most immediate value for this innovation appears to lie in small-scale, high-impact use cases. Businesses operating in hot environments, whether in logistics, manufacturing, or field services, may be among the first to benefit from wearable or portable versions of this cooling technology. If the materials can be manufactured at scale and integrated into clothing or equipment affordably, it could improve productivity, reduce health risks, and lower demand for energy-hungry air conditioning. UK companies involved in the design of smart workwear, industrial safety gear, or modular electronics may also find opportunities in applying or adapting this technology into their own products.
Beyond wearables, the principle behind this cooling system offers a fresh approach to thermal management that could influence future designs in everything from data centres to electric vehicles. For UK firms in clean tech, energy-efficient infrastructure, or defence systems, this could represent a new avenue for collaboration or licensing. It also sits comfortably alongside national net zero goals, particularly in cutting energy consumption and phasing out refrigerant-based systems. However, progress will depend on whether UCLA’s lab success can translate into real-world resilience, cost efficiency, and ease of integration.
The wider lesson is that cooling does not have to mean compressors, gas, or fans. By embedding thermal functionality directly into the material structure, this research challenges long-held assumptions and opens up routes to smarter, lighter, and greener alternatives. For now, the technology is experimental and best seen as part of a wider portfolio of next-generation cooling methods. However, as climate challenges grow and energy costs rise, pressure is mounting on both researchers and businesses to bring practical alternatives like this to market sooner rather than later.