It's not the heat, it's the humidity: HuMaster aims for win-win for humanity and Earth

HuMaster, founded by KIST researcher Lee Dae-young, says comfort can be sustainable when we realize humidity is the key.

HuMaster CEO Lee Dae-young poses for a photo at the company's headquarters in central Seoul. [PARK SANG-MOON]

━ Game Changer

Imagine stepping into a fully air-conditioned oasis in the middle of the a wet, sticky summer in Seoul; a refreshing breeze blissfully dries your sweat away, yet you may find it increasingly harder to ignore the fact that your saving grace, the air conditioner, is likely making the outside even hotter.

As the world gets warmer, demand for cooling spikes, and so does the consumption of energy for it.

“If we do not break this vicious cycle, things will be irreversible,” warned Lee Dae-young, CEO of HuMaster.

HuMaster’s HumiCon could be the ultimate alternative for air conditioners, with a far less severe environmental impact, improved efficiency, and a minimized risk of air conditioning-related sickness, Lee suggested. The product has already found its way into the luxurious homes of some of Korea's largest business moguls, ensuring a mold-free environment without excessively lowering the temperature.

“When we bring our clients into this meeting room during the summer, I tell them later on that the air conditioner on the ceiling was never switched on to begin with,” said Lee, pointing at the barely-used unit.

Much to their surprise, the thermostat reads 28 to 29 degrees Celsius (82 to 84 degrees Fahrenheit), a temperature level mandated in government buildings despite complaints of uncomfortable stuffiness. Yet with the HumiCon up and running, the atmosphere remains as pleasant as ever.

The secret lies in the humidity level, Lee explained.

"As long as the humidity level is low, the atmosphere remains pleasant even in scorching heat, just like how the heat becomes instantly bearable when you go into shade in the desert, Hawaii or the Mediterranean region.”

To put the conditions into context, at a temperature of 32 degrees Celsius with a relative humidity of 30 percent, the humidity index (humidex) — which indicates hot weather’s impact on a person’s well-being — comes in at 34, which is considered to be a pleasant level. But when the humidity rises to 80 percent, the humidex reaches 48, in which the possibility of heat stroke soars.

"Our ultimate goal is to make both people and the environment thrive in good health," said Lee.

Founded in 2018, HuMaster uses desiccant technology to cool the air by modifying the humidity level. The company’s HumiCon reduces humidity through a moisture filter and removes the absorbed moisture using waste heat, resulting in a smaller amount of greenhouse gases.

HuMaster was named a “baby unicorn,” a startup with the potential to become a unicorn company with a valuation of $1 billion, by the Ministry of SMEs and Startups in 2022 and “the Excellent Company of Seoul” by the Seoul city government in 2023. The company so far completed the series A funding round, raising 2.3 billion won ($1.7 million).

The Korea JoongAng Daily sat down with Lee at HuMaster’s headquarters in central Seoul to discuss the company’s journey so far and its plans for global expansion.

This interview has been edited for length and clarity.

Q. How does HuMaster's HumiCon technology work?

A. As global warming brings the temperature up, demand for cooling also rises, and that results in an increase in power consumption and therefore an increase in greenhouse gas emissions, which will eventually accelerate global warming.

If we do not break this vicious cycle, things will be irreversible. This is a global concern not limited to Korea.

Cooling technology with a minimal environmental impact is referred to as green cooling, and this is what we are doing.

During the summer, heat generated at combined heat and power plants, or cogeneration plants, is mostly left wasted because there is no imminent demand. This waste heat could have been used for air conditioning — that way, no energy would go to waste, so two birds with one stone.

This is where I began with technology development.

In Korea, for example, most of the apartment complexes have a district heating system. Therefore, such cogeneration plants are bound to be located near highly populated areas and required to use liquefied natural gases instead of coal, which makes them costly to run.

The profitability is fine during the winter, but during summer when heating demand slumps, it becomes difficult to break even. So if we can run cogeneration plants throughout the year while utilizing heat even during the summer, it will be beneficial for the state-run utilities as well.

During your time as a researcher at the Korea Institute of Science and Technology (KIST), the project hit a snag in the commercialization process. Why was that?

Similar to how the lack of charging systems delays EV penetration, the problem was the infrastructure, as the cogeneration plants halted operation during summer due to low heat demand.

Korea District Heating Corporation won’t switch on a whole plant to provide heating to one household, so we needed to scale up the system to cover at least one apartment building in order to have the central heating system running. Another issue is that district heating systems are available for only about 20 percent of all households nationwide, which significantly limits our accessibility to the larger market.

Moreover, the cooling system market is currently dominated by big players manufacturing air conditioners, such as Samsung Electronics and LG Electronics. To compete with them, our products need to be just as polished, trustworthy and affordable.

To tackle such issues, I came up with the idea of using another type of waste heat, instead of that from the Korea District Heating Corporation — waste heat from air conditioners. By installing a small heat pump used for an air conditioner inside our product, we could utilize the heat generated by the air conditioner.

Then is the HumiCon as effective as a regular air conditioner in regulating temperature?

With further development, the HumiCon may fully replace air conditioners, but we decided to position it as a complementary product in the initial planning stage as we had to penetrate a market that has long been dominated by air conditioners and huge companies.

The strategy is to first make headway in a niche market with a focus on dehumidification demand, and further expand the business to later enter the main air conditioning market.

For example, the atmosphere in basements is cool without air conditioning, but the problem is humidity and mold. If you install a HumiCon there, you can solve the mold problem at the right temperature. Our customers who installed a HumiCon in basements have been very satisfied with the product so far.

How efficient is the HumiCon compared to a regular air conditioner or dehumidifier?

The HumiCon is about 40 percent more energy-efficient than a regular dehumidifier certified with the highest energy efficiency rating. Considering that the difference between the top grade and the second stands at around 10 percent, it is a significant improvement.

In terms of ventilation efficiency, which shows how well a device recovers heat during the ventilation process, our product has been proven to be 1.5 times more efficient than the threshold required to be classified as a highly efficient product.

Moreover, during an eight-month test run conducted jointly with the Seoul city government, we installed HumiCons at about 20 government offices. The result showed a 30 to 60 percent reduction in cooling energy consumption and a drop of over 50 percent in indoor fine dust.

With the HuZero, which is designed for industrial use, we conducted a field test at an operation in Paju, Gyeonggi, and found that our product is about 2.5 times more efficient in dehumidification compared to a major overseas company's product.

Who is your target consumer base?

First, there is demand for basement installation, which is not that large in scale yet, but consumer feedback has been highly positive.

Furthermore, as our product can reduce the humidity without lowering the temperature, vulnerable populations such as young children at kindergartens or the elderly are another major consumer base, especially because the HumiCon reduces the risks of air conditioner sickness.

Government facilities are also a very important target, because they are subject to mandated indoor temperature regulations. There are a lot of complaints about the 28-degree rule, but the temperature is not the problem — the problem is that you cannot dehumidify the air at 28 degrees.

With the HumiCon, you can maintain the temperature at 28 degrees while making conditions pleasant. That way, government facilities will be able to achieve target energy efficiency and also improve the working environment.

At this point, we are working on the high production cost, which has slowed market penetration for us.

Was there any memorable moment during your journey so far?

When we made our very first shipment, a five-ton truck came to pick up our product and deliver it to the customer. I was very excited but also immensely nervous that someone paid money to buy my product; as a researcher at KIST, I never had such an experience before.

My first customer installed our product in a basement at a luxury home in Gyeonggi, and for two months I heard nothing from them — eventually, curiosity got the better of me so I made a phone call. The customer said that they were using it very well, and barely used air conditioning throughout the summer.

Starting from there, the architect of our first client's home recommended our product to a corporate chief of one of Korea's largest companies. Since then, our products have been installed in the basements of properties belonging to household names in Korea.

What is your plan for overseas expansion?

The overseas market is very important for us. The ultimate goal is to replace air conditioners, but for now, our primary strength is in dehumidification technology, so warm and humid regions will be our primary target.

In the Southeast Asian region, for example, you need to wear long sleeves indoors because the air conditioners are running too hard. This is because of the humidity and mold.

In Thailand, we already set up a local office and began operation. Devices such as the HumiCon and HuZero would need more time before the official launch, but we have begun selling the moisture-absorbing materials — which is our core technology — to regular customers in June of last year. For those products, revenue from the Thai market has already outrun the domestic market. The plan is to expand our product lineup into the HumiCon and HuZero.

What is your ultimate goal?

In the short term, we need to enhance our business sustainability by expanding the market and achieving an economy of scale in order to lower production costs. Based on that, we hope to penetrate the bigger market, taking a step forward from the niche market, and to take over the demand for air conditioners.

The ultimate goal is to enter the global market, including the Southeast Asian region. Warm and humid regions with dense populations will be heavily affected by global warming, and the world is trying to reduce greenhouse gas emissions — that means we ultimately need to get into those markets.

Our product is about changing the paradigm of air conditioning. An air conditioner modifies the temperature, humidity rate and such to create a pleasant atmosphere. We tend to think of it merely as cooling the air, but when we change the paradigm with a bigger focus on regulating the humidity level, we will be able to remain healthy and pleasant indoors while also reducing the environmental impact on the Earth.

BY SHIN HA-NEE [shin.hanee@joongang.co.kr]