A large amount of hydrothermal energy recovery over a large surface area 

Approved at a test of the Korea Refrigeration & Air Conditioning Assessment Center

Water has about four times the ability to store energy than air. For this reason, water is cooler than the air in the summer and hotter than the air in the winter. In regions close to the Arctic, such as Russia, they sometimes enter the water and swim during the winter. This is because the water under the surface always contains heat of about 4﹎ unless it is artificially heated or cooled. It is only the surface of the water that is in contact with the atmosphere that naturally cools to ice or evaporates to become water vapor. Heating and cooling using hydrothermal energy takes advantage of this. In summer, the temperature of the water is naturally lower than that of the air. This principle used to cool the air by letting the water take away the temperature of the air. Conversely, in winter, the temperature of the water is higher than that of the air, so the air can take away the temperature of the water for heating. However, it is from the surface of the water that thermal energy can be used from the water. Just as water freezes and evaporates only on the surface of the water, heat energy can be used efficiently only when the surface area where water and the atmosphere come in contact is large. 

Dream One is a company that developed a hydrothermal energy recovery air conditioner that can recover a large amount of hydrothermal energy by taking advantage of this. The recovery air conditioner is an air conditioner that recovers heat energy by artificially creating numerous water droplets by causing a difference between the spraying force and rotational force of the water supplied to the air conditioner. The reason why it is made into water droplets by spraying and rotating is to maximize the surface area. Existing hydrothermal energy recovery methods used gravity to let it flow down on the surface, and water to fall and contact air by using spraying force and gravity at the same time. However, in this case, the surface area itself is not very large because the water aggregates due to surface tension or only reaches the atmosphere in the form of a water column. On the other hand, the hydrothermal energy recovery air conditioner artificially creates numerous water droplets and can dramatically improve the hydrothermal energy recovery efficiency compared to other methods due to the large surface of the sphere of the water droplets. Dream One said, “As a method of cooling the data, a plan to use deep low-temperature water from the Soyang River is being proposed. The water-to-air water-to-air heat exchanger is capable of exchanging a large amount of heat, and it can adsorb and remove fine dust in the inhaled air with the adsorption power of water to supply clean cold air to the data center. The free cooling type hydrothermal energy recovery air conditioner that exchanges heat from water to air can exchange a large amount of heat. Even fine dust in the inhaled air can be adsorbed and removed by the adsorption power of water, and clean cold air can be supplied to the data center.” In addition, since no separate refrigerant or greenhouse gas is used for cooling and heating, concerns about air pollution are fundamentally eliminated, and energy consumed for operation is greatly reduced due to structural characteristics as the propulsion using spraying is dependent on water pressure.

Dream One’s air conditioners have received official performance test certification and attracted great attention at the Heating Air Conditioning Refrigeration and Fluid Exhibition 2022. The test was carried out by the Korea Refrigeration & Air Conditioning Assessment Center. It showed an average temperature increase effect of 6.2﹎ during the warm air test and an average temperature decrease of 15.37﹎ during the cold air test. The prototype, which was actually manufactured, proved its effectiveness by test-operating in some data centers in Korea through the Hydrothermal Energy Convergence Cluster in Gangwon-do. 

Efficient cooling with a large surface area

Replacing fillers, cooling tower without worrying about industrial waste

The technology of recovering a large amount of heat energy through the surface area of a sphere secured from numerous artificially created water droplets can be used in various fields other than hydrothermal energy recovery air conditioners. One of them is Dream One’s coolant rotary jet cooling tower. Dream One’s cooling tower is the world’s first cooling tower that removes the filling inside the cooling tower and uses the method of cooling through water droplets created by rotating and spraying the cooling water supplied to the cooling tower. The filler is a heat transfer medium that allows direct contact between the air flowing into the cooling tower and the circulating water. Since this filler needs to be continuously replaced, industrial waste is generated along with costs associated with it, but Dream One’s cooling tower does not use filler, which can solve this problem.

Dream One’s cooling tower not only splits into water droplets, but also sprays them horizontally, so the water droplets stay in the air for a long time. The large surface area and long flight time make the heat energy exchange more efficient. Dream One said, “This is a new type of eco-friendly energy-saving next-generation cooling tower that additionally saves blowing energy at the same time, and is a product that will rewrite the history of future cooling towers.”

▲ Dream One / CEO Kwon Yong-jun

Air cleaning effect without filter: water rotation spray type air cleaner

After it rains, the air is clear. This is because dust in the air is adsorbed to the raindrops and falls to the ground along with water. Dream One’s water rotary jet air cleaner is also based on the same principle. The fine dust in the indoor air is absorbed by the water droplets sprayed while rotating, and through this, the internal quality of the air can be improved. As water droplets with a large surface area are used, more dust can be adsorbed.

Another strength is that it does not require a filter like other air purifiers because it uses a method of adsorbing dust in water. Dream One’s technologies can be applied to data center coolers, water convection circulation oxygenators to prevent red algae and algal blooms. Dream One said, “Our products reduce greenhouse gases and at the same time absorb and remove fine dust to protect the global environment.”