Research on the development of a small-scale supercritical carbon dioxide power cycle experimental loop with a high-speed turbo-generator

A supercritical carbon dioxide power cycle which is known as one of promising power cycle for a concentrating solar power (CSP) has technical challenges of operation near critical point and under high pressure/temperature conditions, and challenges of turbomachinery and bearing technology. Therefore, a small-scale simple supercritical carbon dioxide power cycle experimental loop was designed and manufactured to obtain diverse basic data of operational characteristics, control and stability of this power cycle, and to utilize these data for following scale-up research. As the first step, 1 kWe-class high speed turbo-generator and experimental loop for a 200 °C of supercritical carbon dioxide were designed and manufactured. A carbon dioxide is pressurized up to 130 bar by piston-type pump and heated up by an immersion electric heater, then drive a turbo-generator. A diameter of turbine wheel and rotational speed was designed to 22.6 mm and 200,000 rpm respectively. A commercial angular contact ball bearing was applied to the turbo-generator