Large electrical generation companies use so-called peaking generators to carry additional load when demand for electrical power is particularly high.Running these generators at very low loads is bad for them for a number of reasons.A particular peaking generator carries an average load of 20 MW, with standard deviation of 4.23 MW.If this generator's low load threshold is 10 MW, what percentage of time is this generator being run at a low load condition?
A) 0.91%
B) 2.36%
C) 99.09%
D) 1%

Question

Quizplus · Accepted Answer

The z-score for a load of 10 MW is (10 - 20) / 4.23 = -2.36. The percentage of time the generator is being run at a low load condition is the area under the normal distribution curve to the left of z = -2.36, which is 0.91%.

Large Electrical Generation Companies Use So-Called Peaking Generators to Carry