The color of the future: Australian innovation that cools buildings and creates water from air in the apartment

From idea to startup

Their work grew into the startup Dewpoint Innovations, founded in 2022, with ambitions that go beyond just cooling paint. Their vision is a broader change in the way infrastructure is designed. If roofs across the city could reflect heat and collect water, they would become an active part of the solution to climate change.

In a warming world, cities are becoming heat traps. Concrete and roofs absorb the sun’s energy, raising the temperature and creating the so-called urban heat island effect, due to which cities are significantly warmer than their surroundings. That’s the first challenge that Dewpoint Innovations is targeting.

​- Our paint will significantly reduce the heat load that the sun puts on cities – said Chiu, co-inventor and chief technology officer of the company.

In order to achieve this effect, specially designed nanomaterials use the process of passive radiation cooling. They reflect most of the sun’s energy and release heat back into the sky, allowing roof surfaces to stay cooler than the surrounding air without consuming energy. Similar technologies are being developed around the world. For example, “ultra-white” paint from Purdue University can reflect up to 98.1 percent of sunlight, they use barium sulfate as a pigment, which makes surfaces cooler than the environment.

Incredible results on the field

During a six-month outdoor test, Dewpoint’s coating showed solar reflectance of up to 96 percent. This high reflectivity means that less heat was absorbed, keeping roof surfaces up to six degrees Celsius cooler than the surrounding air and reducing heat transfer into buildings. In a three-month field trial in Sydney in late 2023, a roof painted with their paint stayed up to 30 degrees Celsius cooler than a standard dark roof. According to estimates, this translates into a reduction of energy consumption for household cooling by up to 34 percent.

For Professor Baohua Jia, a nanotechnology expert from RMIT University who is not affiliated with the project, these results point to a wider potential. She believes this roof coating offers a scalable way to combat the urban heat island effect.

​- This technology can potentially drastically reduce temperatures in urban areas, alleviate heat stress and reduce dependence on air conditioners, making it a tangible tool for adapting to climate change in densely populated areas – said Jia.

Water from the air with one stroke of the brush

In addition to cooling, the coating has another, equally impressive function.

​ – One of the amazing properties of a surface that maintains a low temperature while the rest of the environment heats up is that it encourages the condensation of moisture from the air on its surface – Dewpoint CEO Perzaan Mehta told CNN.

It’s the same basic process that causes water droplets to form on the outside of cold čash. Although the system is still in the development phase, early tests have shown that it could collect 74 liters of water per day from a roof area of ​​200 square meters. Mehta explained that this is approximately the amount of water used during a five-minute shower in areas with abundant water.

Potential and limitations

Although it cannot replace the entire water supply for households, Mehta says that it can serve as a supplementary source.

​- It will help reduce the load, but it is not a panacea – he added.

Through modeling the data collected so far, Dewpoint has determined that a minimum relative humidity of about 70 percent is required for water collection. Such conditions are present in coastal, tropical areas such as Singapore or the Amazon basin. It is precisely from these regions that the greatest international interest comes. In the broader context of technologies for harvesting water from the air, scientists at MIT have developed systems using hydrogel, while others have made significant progress with metal-organic frameworks (MOFs), porous materials that can trap water molecules even at low humidity.

Pomoć wild animals

In addition to human applications, cooling technology could also help wildlife, Chiu said, by reducing heat stress under animal shelters and providing water during droughts. Images of firefighters giving water to dehydrated koalas during the catastrophic fires in Australia between 2019 and 2020 shaped Chiu’s thinking about harvesting atmospheric water.

​- Water harvesting systems could be set up in remote locations to generate water from the air and provide wildlife with access to drinking water when they cannot find it anywhere else, Chiu said.

The way to the market and the future of cities

Dewpoint is currently preparing for more extensive trials of its paint on Australian roofs, and potentially overseas, with the aim of commercializing the product through Haymes Paint. Andrew Brewer, manager of Haymes Paint, expressed his excitement about bringing this sustainable technology to market. However, he also highlighted the obstacles.

​ – Construction contractors stick to proven products – Brewer said, adding that acceptance will depend on independently verified performance, whether energy savings justify the initial cost and compatibility with standard application methods.

Mehta said they expect the price to be similar to functional paints, which are usually 50 to 100 percent more expensive than regular paint.

Challenges and vision of sustainable urbanism

Radiant cooling products still face challenges such as durability, reduced performance in cloudy conditions, and a lack of standardized testing and building regulations, as Jia pointed out. However, he adds that these problems are being actively worked on and it is expected that improvements in materials, design and production will make the technology more reliable and more widely accepted. The ultimate vision of Dewpoint is for their color to become an integral part of urban planning and development.

​- I think it would be fantastic to see Dewpoint as part of the tools urban planners and architects have at their disposal in the future and for products like ours to become part of the regulatory framework for how we think about designing cities – said Mehta.