Blackouts only happen in Puerto Vallarta if there is a big storm. It doesn’t happen a lot and it usually doesn’t affect the entire area of Puerto Vallarta.
In some areas, like Lo de Marcos, since it is a very small town in the area, blackouts happen more often when it rains and in the summer. (Lo de Marcos is on the coast, about one hour by car north of Puerto Vallarta.) When a blackout happens in Lo de Marcos, you just light your candle, have a glass of wine, and enjoy the darkness. It doesn’t happen very often; blackouts happen about twice a year and it lasts for about 2 hours unless if there is a big storm, in which case, it could take longer depending on how severe the weather is.
Most of the big houses in Lo de Marcos have their own generators because in the beginning, there was no electric service coming into the town so you had to provide for your own. Now that there is electric service, most of the big houses kept their generators, which is what they use in case there is a blackout. Other houses, instead of buying generators, installed solar power systems.
Overall, blackouts do not happen in Puerto Vallarta unless there is a very huge storm or if lightning struck one of the power generators, which rarely happens.
(The view from a villa in "Gringo Gulch," Puerto Vallarta, Mexico, pictured.)