However, because skilled service personnel are required, gas turbines of this type are often taken off site for maintenance. They require high quality fuel and may experience a fall in output and efficiency after a long period of operation. The generator room at Sithe Energy's gas-fired cogeneration facility at Smithfield, Sydney The industrial gas turbine, also referred to as the heavy duty or heavy frame gas turbine, is a robust unit constructed for stationary duty and continuous operation. It has a lower efficiency than the aero-derivative type, but usually maintains its performance over a longer period of operation. Maintenance can easily be carried out on site.
Maintenance costs are low.
The industrial gas turbine usually has a lower specific investment cost than its aero-derivative counterpart. Furthermore, it can use lower quality fuel. Heat is recovered in a boiler by using the hot exhaust gases to produce steam or hot water. The boiler may be unfired or employ supplementary firing. It is possible to dispense with the heat recovery boiler in applications where the exhaust gas heat can be used either directly for air preheating or drying, or indirectly, by passing the gases through a heat exchanger to produce hot water or steam for process needs.