4.7 Cogeneration Systems and Operation

The benefits of a combined-cycle with a single shaft gas/steam turbine arrangement are:
1. High level of thermal efficiency
2. Low capital cost
3. Fast start-up and shut down
4. Short construction time
5. Low maintenance cost

_________ is well known for its contribution to the greenhouse effect

In a cogeneration system the thermal load can be controlled by which two of the following strategies
1. Fixed production of a minimum thermal energy
2. Varying requirements for thermal energy
3. Base loaded for maximum thermal energy
4. Topping for minimum thermal energy

Which of these cogeneration systems does the following description best describe?

"The compressor driven by the gas turbine supplies pressurized combustion air to mix with fuel and burned in the boiler. The steam produced by the boiler is used to drive a steam turbine that is connected to an electrical generator. The exhaust gases from the boiler are then fed to the gas turbine which is connected to a second electrical generator. "

When additional thermal energy is required in a cogeneration system, a _____ is often used

HRWH stands for

A _____ system has the electrical supply from the utility grid fixed and the cogeneration system looks after changing electrical requirements.

The primary purpose of cogeneration is to:

In order to counter the corrosive nature of the condensate produced from burning fuel with high sulphur content, a _____ heat exchanger is installed in the condensing heat recovery systems.

During low thermal requirement periods of a cogeneration system a diverter valve is used to direct the: