Supercritical-CO2 Brayton cycle has been recently gaining a lot of attention for the mild temperature (450 550 degrees C) heat source application due to its high efficiency and compact footprint as the system layout of S-CO2 cycle is simple and small turbomachinery and compact micro-channel heat exchangers are utilized. As CO2 properties behave more like an incompressible fluid near the critical point (30.98 degrees C, 738 MPa), the control of compressor operating condition and stability is the key technology that influences the cycle efficiency. Based on the previous works on the S-CO2 test facilities from various research institutions, a Korean research team designed the SCIEL (Supercritical CO2 Integral Experiment Loop) to achieve higher efficiency with higher pressure ratio with S-CO2 power cycle compared to other pre-existing facilities. This paper will describe the underlying design principles of the integral experiment facility and the current status of SCIEL which is being constructed in KAERI (Korea Atomic Energy Research Institute). (C) 2015 Elsevier Ltd. All rights reserved.