A Balance druid using a Solar eclipse rotation will generally start by casting faerie fire, dots, and then begin to cast Starfire until it crits, which will give the druid the Eclipse effect. For the next 15 seconds, the druid's Wrath spell will have a significant damage boost (40%), with a 15 second downtime before Eclipse may be procced at all.
Solar eclipse rotations are generally better to use when the druid's haste rating is below 400. It is subjective and arguable whether or not a lunar or solar rotation is better, but the druid should definitely not use a solar eclipse rotation if haste rating is significantly higher than 400. Some druids will purposefully lower their haste to be able to use solar eclipse, but others are still highly in favor of lunar eclipse. In certain situations, however, a solar eclipse can still be better than a lunar eclipse, particularly on trash that will die quickly or on boss fights like Loatheb.