An excellent point that utility costs are largely fixed, especially operating costs (infrastructure costs are sunk). As with most things, Puerto Rican emigration seems to bring both advantages and disadvantages for those looking to immigrate.
The obvious advantages are lower costs for land and pre-existing housing. Lower costs as well for many services, as a decrease in demand means a drop in price, at least for all of those goods which my economist friends refer to as "elastic".
Public utilities and many public services however are more "inelastic," less sensitive to the effects of supply and demand on cost. However, even here we can protect ourselves. Others have written elsewhere on the forum about the wisdom of backup generators to provide power when PREPA fails. Recent (last couple of decades) advances in solar power generation make solar electricity an increasingly attractive means of providing residential power on the island, and the cost of an individual's producing solar power (i.e. the kw/h cost of solar) sets a limit on the price imposed by PREPA. Simply, if PREPA sets the electricity price too high, buy solar panels.
Similarly, water is another public utility that can be, and frequently is supplemented by individual consumers. Cisterns are common on the island, and though they frequently supply non-potable water, the addition of a residential reverse-osmosis water purifier can provide the potable water needs at a fairly low cost per gallon.
While it is painful to witness these demographic changes to Puerto Rico, I must confess that I am fascinated by them, and by the opportunities that they pose for those who can see them.
