Harnessing Waste Heat is the Latest Frontier in Data Center Efficiency

🌈 Abstract

The article discusses the growing trend of data centers adopting waste heat reuse solutions to enhance energy efficiency, mitigate environmental impact, and reduce operational costs.

🙋 Q&A

[01] Data Center Energy Efficiency and Waste Heat Reuse

1. What are the key challenges and opportunities in utilizing waste heat from data centers?

• Data centers are facing the challenge of heat rejection from chips to the facility, as the quantity of waste heat is increasing with the addition of AI applications and more liquid cooling.
• Channeling waste heat out of the facility is one approach, but it is more efficient and environmentally friendly to utilize waste heat to generate power, steam, heating, or even cooling.
• Waste heat reuse can help data centers reduce the cost burden and their carbon footprint.

2. How can data centers maximize the value of waste heat?

• Collocating data centers within multifunction buildings or campus settings can provide opportunities for sustainability and efficiency, as the waste heat from data centers can be harnessed to reduce overall energy consumption and lower power usage effectiveness (PUE).
• Locating data centers in larger communities and integrating them into broader energy solutions can help maximize the value of waste heat, as data centers can leverage the heating demands of the surrounding buildings.

[02] Case Studies of Waste Heat Reuse

1. What are the key features of the waste heat reuse system at the Milwaukee School of Engineering?

• The computer science building with a supercomputer (Rosie) was designed to have a symbiotic relationship between the academic building energy systems and the supercomputer systems.
• During summer, the computer room and academic building use the same cooling system, with the chilled water return line used for data center supply to increase cooling efficiencies.
• During winter, the computer facility utilizes cold outside air via dedicated air-cooled roof-top condensers and integrated free-cooling circuits.

2. How does the NREL Energy Systems Integration Facility (ESIF) utilize waste heat?

• The ESIF was designed to match the heating demands of its labs and offices with its supercomputer-based data center to make the entire building more energy efficient, achieving a PUE of 1.04.
• 100% of office heating is done through waste heat reuse, and water use has been cut in half.
• The facility has an energy recovery water loop that spans campus heating and cooling systems, supercomputing systems, and legacy IT systems, gathering waste heat from both liquid and air-cooling systems.

3. What are the potential incremental gains from addressing waste in data centers?

• Liquid cooling could result in a major shift in data center cooling efficiency and lower PUEs, but the potential gains could be squandered due to various areas of waste, such as lack of hot air containment, missing blanking panels, and failure to replace power-hogging fans.
• Addressing these areas of waste can lead to incremental gains in data center energy efficiency.