Chronology Current Month Current Thread Current Date
[Year List] [Month List (current year)] [Date Index] [Thread Index] [Thread Prev] [Thread Next] [Date Prev] [Date Next]

Re: [Phys-l] black start



John Denker's post about using gas turbines to provide cold-start capability at coal or nuclear-driven steam-turbine power plants seems like a good idea. However, here are some questions for which I don't know the answers.

[1] Would a single 10 MW gas turbine installed as part of the cold-start procedure be of any value as a "peaking generator" for a power plant that has 400 MW steam-generated power capacity? That's only an additional 2.5% above the regular plant capacity. Most gas-turbine peaking plants seem to be anywhere from 200 MW up to 1 GW capacity. A 200 MW peaking plant might consist of four 50 MW gas turbines that can be brought online one at a time as needed. My first guess is that a gas turbine with a capacity of 10% of the smallest generator it needs to cold-start would not be large enough to be of much value as a peaking generator for the plant it services if the plant's normal capacity is provided by some reasonable number (say 4 to 8) of the steam generators for which the gas turbine needs to start just one. That is, the gas turbine's capacity would only need to be 10% of the smallest generator it needs to cold-start, but then it could only provide in the ballpark of 1% to 3% of the normal operating power of that plant once all the steam-powered generators are operating. Peaking capacity of 1% to 3% of the plant's normal capacity does not seem enough be worthwhile. Therefore, would the cost of the gas-turbine generator really be offset by its use as a peaking generator?

[2] How does the cost of a small gas turbine generator compare to the same-sized diesel generator? I think the gas turbine costs a lot more. Is that correct?

[3] How many steam-turbine power plants have a natural-gas pipeline available; particularly a natural-gas pipeline large enough to power a gas-turbine having 10% of the capacity of the smallest steam-generator it needs to start? If such a pipeline does not already exist, how much would it cost to run one to the plant?

Michael D. Edmiston, PhD.
Professor of Chemistry and Physics
Chair, Division of Natural and Applied Sciences
Bluffton University
Bluffton, OH 45817
Office 419-358-3270
Cell 419-230-9657