For a diesel generating station the useful life is expected to be around

15 to 20 years
20 to 50 years
50 to 75 years
75 to 100 years

The correct answer is B. 20 to 50 years.

A diesel generating station is a type of power plant that uses diesel fuel to generate electricity. The useful life of a diesel generating station is typically 20 to 50 years. This means that the station can be expected to operate for 20 to 50 years before it needs to be replaced.

There are a number of factors that can affect the useful life of a diesel generating station, including the quality of the fuel, the maintenance schedule, and the operating conditions. If the fuel is of poor quality, it can damage the engine and shorten the life of the station. If the station is not properly maintained, it can also shorten its life. And if the station is operated in harsh conditions, such as extreme temperatures or high humidity, it can also shorten its life.

However, with proper care and maintenance, a diesel generating station can provide many years of reliable service.

Here is a brief explanation of each option:

  • Option A: 15 to 20 years. This is a possible range for the useful life of a diesel generating station. However, it is on the lower end of the range.
  • Option B: 20 to 50 years. This is the most likely range for the useful life of a diesel generating station.
  • Option C: 50 to 75 years. This is a possible range for the useful life of a diesel generating station. However, it is on the higher end of the range.
  • Option D: 75 to 100 years. This is not a realistic range for the useful life of a diesel generating station.