Development of High Efficiency Gas Turbine/Fuel Cell Hybrid Power Generation System

Jae Hwan Kim[1], Soo Seok Yang[2], Dae Sung Lee[3]

Responding to a rapid increase in the demand of the electrical power and diminishing source of the fossil fuel, challenges to develop highly efficient prime movers and economical power generation methods have been continued. Furthermore, global warming and environmental issues make these challenges enter on a new phase, leading to tremendous efforts to develop power generation systems based on various new concepts.

Recently, the integration of a fuel cell with a gas turbine is emerging as a potentially attractive way to generate electricity and heat with high efficiency and very low emission. This synergetic hybridization attributes to the progress in fuel cell technologies and the matured environment in gas turbine industries.

The concept of the fuel cell/gas turbine hybrid system is based on the idea that the performance of a high temperature fuel cell can be enhanced by using a gas turbine as a cathode gas (air) supplier instead of a typical blower. Such a combination results in the high electricity generation efficiency of the fuel cell itself at pressurized environment without the separate power for the air supply and surplus power generation of turbine except for compressor driving. The fuel cell is like a combustor that generates electricity with extremely low emission from the viewpoint of the gas turbine design. A number of R&D programs related to hybrid systems have been intensively carried out over the world for last ten years. These R&D activities and the need for novel power generation systems in Korea has initiated the launch of the project ‘Development of High Efficiency Gas Turbine Fuel Cell Hybrid Power Generation System’ in 2002 supported by Korea Ministry of Commerce, Industry and Energy.

This paper describes this on-going national R&D program and related R&D activities in Korea. The final goal of this program is to develop a 200kW-class gas turbine/fuel cell hybrid power generation system and achieve high efficiency over 60% (AC/LHV). In the first phase of the development, a sub-scaled 60 kW class hybrid system based on the 50kW class microturbine and the 5kW SOFC will be developed for the purpose of concept proof of the hybrid system. Core components such as the microturbine and the SOFC system are being developed and parallel preparation for system integration is being carried out. The 60kW demonstration unit will be built up and operated to provide the valuable information for the preparation of the final full scale 200kW hybrid system.