Energy and economic assessment of major free cooling retrofits for data centers in Turkey
Energy and economic assessment of major free cooling retrofits for data centers in Turkey
Mechanical cooling is responsible for a significant fraction of the energy consumption of data centers (DCs).Free cooling systems take advantage of ambient conditions to reduce the need for compressor-based cooling. This studyutilizes thermodynamic models of major free cooling systems such as the direct air-side economizer (ASE), indirectair-side economizer (IASE), indirect evaporative cooler (IEC), and indirect water-side economizer (WSE) integratedwith the existing cooling infrastructure of a typical 1 MW IT load DC. Proposed models utilize hourly weather data ofvarious cities in Turkey to compute annual energy consumption and cost-saving potentials of each free cooling methodwith respect to the baseline DC with both open aisle (OA) and enclosed aisle (EA). Results confirm the energy-savingpotential by IEC leading to less than 10% of annual chiller hours across Turkey and less than 1% in half of the tencities studied, especially in EA DCs. However, despite greater energy-saving potential, IEC has more extended paybackperiods of 1.5 to 3.7 years due to the high capital investment compared with those of ASE and WSE with less than 1.4years.
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