As an increasing number of data centers work to cut their electricity usage, finding more efficient cooling methods has become a higher priority for the industry. One of the most efficient approaches to cooling is a cooling tower. A cooling tower uses evaporative cooling to cool water and reject heat from the data center.
This type of evaporative cooling can be very effective for indirect data center cooling systems. Though it tends to have high water usage, its energy usage is relatively small.
A cooling tower is an evaporative cooling technology that focuses on cooling water, unlike traditional evaporative coolers, which focus on air cooling.
In the data center, water takes heat from the air or directly from server racks. Pumps take the hot water from the data center to the cooling tower. The water runs through pipes in the cooling tower until it reaches sprayers. These sprayers spray the hot water onto a fill material. The fill material, also called the packing or baffles, is honeycombed to catch water while letting air pass through. It’s similar in principle to the evaporative media in an evaporative cooler. Unlike evaporative media, cooling tower fill doesn’t absorb the water – it simply breaks it into small droplets or a thin film to increase contact with blowing air.
Meanwhile, the cooling tower draws in cool, dry air. Fans suck the air through the fill, and as the air passes through the hot water, some of the water evaporates. Evaporation requires considerable energy, which the water draws from its own heat. Meanwhile, the cool air also picks up heat from the water. This leads to warm, wet air that rises out of the cooling tower. This is why cooling towers often give off steam, especially on cool days.
The water that doesn’t evaporate soaks to the bottom of the tower, considerably cooled. This cooled water is then pumped into the facility to perform more cooling.
Data centers use cooling towers to get efficient cooling. Cooling is the highest category of energy use besides actual processing. By achieving more efficient cooling, data centers can improve their power use efficiency (PUE), which lets them operate at a lower cost and be more competitive in a challenging market.
Although the initial investment in cooling towers can be significant, the savings in energy costs can quickly add up, paying off the initial investment within two years. Cooling towers offer large-scale cooling, which can help some of the largest data centers meet their oversized cooling demands.
Some people are concerned that evaporative cooling, such as cooling towers, significantly increases the water usage by data centers. However, a full-scale analysis that factors in water usage during power generation shows that cooling towers actually reduce water consumption overall.
Cooling towers typically operate as part of an indirect cooling system. The water from the cooling tower absorbs heat from the air in the data center. Although this is efficient, it might not be as efficient as direct air cooling in the data center.
Direct air cooling utilizing evaporative media in an evaporative cooler can take heat directly from the air, cooling it rapidly. Evaporative media like Kuul Evolution FirePro™ can operate with extreme efficiency. This evaporative media can maintain 98% saturation at low air flow rates and remains over 90% saturated even at the highest air flow rates. The media also presents 20% less resistance to blowers, which lets evaporative coolers operate with even less power. Plus, Kuul Evolution FirePro™ meets the difficult fire standard UL 900.
Want to learn more about the benefits of using Kuul evaporative media in your data center? Please contact us today with questions or to make an order. You can also schedule a free video conference.