In my opinion, should you consider adding a generator, one should then have BOTH (an inverter system too). The reasoning being, that currently you can, almost daily, have short power cuts created by switch overs. You may not want to experience these cuts or see (and hear) your generator turn on for a cut of 30 sec. to 5 minutes, just to shut down again. With a limiter timer, you can set your generator to turn on only after an extension of a power cut is recorded. Thus saving gas/diesel and your generator's health and actually not have to "notice" all these little interruptions one way or the other.
May I add, that the Sosua/POP region has a variety of "preferential" and not so preferred lines and power networks. Meaning that within this broad region, you may find neighborhoods which offer what the call 24/7 "uninterrupted" service (which still can experience short cutoffs and occasional not so short ones) and others which have only occasional electrical service, and some in between.
In POP, some newer neighborhoods on the East end, have private electricity coming from the power station built for the tourist complex (Playa Dorada), which is said to be very reliable but more expensive (some actully have both there, the PD and EdeNorte).
... J-D.