Collaborative Advanced Gas Turbine (CAGT) Program Status: An International Initiative to Catalyze an Intercooled Aeroderivative (ICAD) Gas Turbine Launch Order

Abstract

This paper describes the status of the Collaborative Advanced Gas Turbine (CAGT) Program’s initiative to commercialize interCooled AeroDerivative gas turbine (ICAD) technology. CAGT is a consortium of domestic and international electric companies, gas companies and research organizations. ICAD gas turbine technology was selected by CAGT member companies and potential suppliers in a competitive $5 million screening study of various advanced gas turbine options in the 1992–94 time frame. Efforts to commercialize ICAD began in 1994–95. The most attractive ICAD gas turbine options were based on high thrust engines produced by General Electric. Pratt & Whitney and Rolls Royce aircraft divisions. Simple cycle ICAD represents a new intermediate load gas turbine product class with costs and performance unlike any other product available today. Simple cycle efficiencies will approach Chose of many operating combined cycles, but with the low capital costs and rapid start times of a peaking gas turbine. ICAD simple cycle units would be in the 100–130 MW size range with efficiencies in the range of 45–48% + LHV and combined cycle efficiencies potentially as high as 60% + LHV. All efficiencies are presented in the paper in lower heating value (LHV). ICAD gas turbines will eddress a wide range of simple cycle, cogeneration. innovative repowering, combined cycle, distributed generation and renewable energy applications. CAGT members have several projects underway with the goal of the first ICAD unit to begin operation before the year 2000. Industry restructuring has reduced near-term demand for new generation in the United States with a corresponding drop in gas turbine prices. Given the large development cost for any new gas turbine product, potential ICAD suppliers have indicated the need for a launch order to proceed with development. CAGT is pursuing a number of project development and strategic alliance strategies globally to organize a launch order in the range of 10–15 projects. Efforts are also underway to examine options for demonstrating ICAD on a smaller scale (Small ICAD or SICAD) which would address the emerging market for distributed generation. CAGT members feel the low costs and flexibility offered by ICAD could be a significant source of competitive advantage in restructuring electric markets. CAGT members invite others to join the program.

Water spray cooling of gas turbine cycles

“…Results are therefore shown for intercooling by 25°C and 50°C (the LP compressor discharge temperature is about 80°C above ambient; therefore the 50°C case is not too far removed from a realistic level of intercooling). In the 25°C case, the HP spool non-dimensional speed is increased by about 5 per cent and, in the 50°C case, it is increased by about 10 per cent; this illustrates the fact that the full benefits of conventional intercooling are unlikely to be realized without significant modifications to either the HP or the LP compressors, as illustrated in reference [18]. Results are shown for the cases in Table 3.…”

Emergence of Recuperated Gas Turbines for Power Generation

“…With a simple cycle aeroderivative engine in the 50Mw class having demonstrated an efficiency of around 42 percent, interest has been expressed in how such an engine might evolve for utility power generation (Davidson, 1996). Unlike the typical heavy duty single shaft industrial gas turbine, the multi-spool construction of aeroderivatives facilitates the use of a conventional intercooler.…”

Flow Development in an Annular Contraction

“…Multiple inlets are necessary in gas turbines with cycle modifications such as intercooling, i.e. cooling of air between the low pressure (LP) and high pressure (HP) compressor sections (Shepard et al, 1995;Davidson et al, 1996;Agrawal et al, 1995). In an intercooler system, the LP discharge air is decelerated in a diffuser prior to the cooling in a heat exchanger or intercooler.…”