Hydrogenerator Line Charging /Condensing Ability:

Could somebody justify the following statements in a manual:

If the generator will be required to energize relatively long EHV transmission lines, the line-charging requirements should be calculated and a generator with the proper characteristics specified. The line-charging capacity of a generator having normal characteristics can be assumed to equal 0.8 of its normal rating multiplied by its short-circuit ratio, but cannot be assumed to exceed its maximum rating for 70 °C temperature rise. Often it will be desirable to operate generators as synchronous condensers. The capacity for which they are designed when operating over-excited as condensers is as follows, unless different values are specified:

Power Factor / Condenser Capacity

0.80 / 65 percent

0.90 / 55 percent

0.95 / 45 percent

1.00 / 35 percent