Answer
This is not possible.
Work Step by Step
If 30 MW of electrical power is produced, we multiply that number by $\frac{1\;hp}{746W}$ to convert to horsepower. The result is 40214 hp. This is over 40 percent greater power than the 28000 hp engine that purportedly drives the generator. Energy is conserved, and the generator cannot output electrical energy at a greater rate than the diesel engine supplies energy to it.