Data Centres
HFCs, including R-134a and R-410A, and HFOs are widely used for data centre cooling. Compressors range from scrolls to high capacity centrifugal chillers, which have large refrigerant charges.
Large data centres use massive amounts of energy to process and store data.
Similar quantities of energy can be required for cooling to maintain the required data operating temperature. The development of Artificial Intelligence (AI), the Internet of Things (IoT) cloud computing and smart technology are expanding data centre installations. Blockchain and high-frequency trading systems are processor and energy intensive. The large demand for data centre cooling drives the requirement for higher efficiency.
Free cooling is clearly the most energy efficient option
Due climatic conditions it cannot be used in all locations throughout the year, which means that most data centres have a close control air conditioning system to maintain the required temperature range particularly in summer. High system reliability and close temperature control are critical. Well-designed chillers when combined with a free cooling chiller, can deliver up to 98% free cooling for most European data centre hubs.
Free Cooling uses low external air temperatures to chill water and generate energy savings.
It can take effect when the difference between the outside supply and return temperatures is as little as 1°C and reduces the need for mechanical cooling, Concurrent free-cooling maximises the part-load efficiencies when mechanical refrigeration compressors are operating. The use of temperature sensors and sequencer controls allows for cooling to be staged, ensuring a smooth transition from mechanical cooling to air free cooling.
Power usage effectiveness (PUE)
Is the ratio of total amount of energy used by a computer data centre facility to the energy delivered to computing equipment and describes how efficiently a computer data centre uses energy; specifically, how much energy is used by the computing equipment (in contrast to cooling and other overhead). An ideal PUE is 1.0. Free cooling opportunities can make a significant saving on energy use generating PUEs of 1.1 or below. The most common systems make use of Air cooling technologies or immersion cooling technologies.