Because conditions can vary widely from one data center environment to another, efficiency and performance cannot always be optimized with a single cooling strategy. In some cases, a mix of open loop (cooling that requires some degree of interaction with the ambient data center environment to function properly) and closed loop (cooling that is completely self-contained and doesn’t interact with the surrounding data center environment) cooling is the best way to address the situation. Taking advantage of the flexibility found in its Liquid Cooling Packages (LCPs), Rittal can provide a combination configuration that unites the best of both the LCP+ (closed loop) and the LCP Inline (open loop) cooling systems to meet these specialized application requirements with a single cooling unit.

This Rittal solution is an LCP Hybrid with a perforated front door and rear aisle containment—an LCP Inline unit with a solid LCP+ rear door. This setup can deliver 30-44 kW of cooling capacity, and can operate with substantially warmer inlet water than competitive offerings, with optimized cooling around 59° F, to deliver up to a 45% increase in energy efficiency. As a combination solution, the perforated front door allows cool air to flood the cold aisle of the data center while the solid rear door contains the heat that would normally exhaust to the hot aisle. Since the LCP Hybrid is installed in-row and the rack enclosures being used in this configuration would have solid rear doors as well, the hot air is forced back into the heat exchanger with a series of six fans—preventing any hot air from entering the data center. This is ideal for data center applications with mixed load densities because an LCP Hybrid unit can cool multiple enclosures at once as the cold aisle air circulates, cooling low, medium and high density server loads along the way.

In addition to the energy and performance advantages of employing an in-row, hybrid open and closed loop solution, are the benefits of convenience. As mentioned previously, Rittal’s hybrid LCP configuration can cool multiple, mixed-density enclosures at one time, which eliminates the need for multiple cooling units tailored to each particular need, e.g., liquid cooling units for high density enclosures, and air conditioners or fans for low-to-medium density loads. The convenience of a hybrid solution extends even further when data center safety systems are taken into consideration. With closed loop solutions, special provisions must be made for proper fire suppression because all of the components are wholly contained within the enclosures. Using a hybrid liquid cooling approach, since only the rear of the system is contained, existing facility fire suppression and safety equipment can be used without making modifications.

For applications requiring the cooling of mixed load densities, or even those with consistent loads where it’s beneficial to spread the cooling from one source to an entire row of enclosures without using a hot aisle, a solution like Rittal’s LCP Hybrid can provide the ideal blend of performance and efficiency.