(Reuters) - Hurricane Maria was on course Tuesday to slam Puerto Rico with a direct hit that could devastate the island s underfunded power grid, still recovering from Hurricane Irma two weeks ago. The Category 5 storm, the top end of the five-step Saffir-Simpson scale, could strain the resources of the island s power provider, Puerto Rico Electric Power Authority (PREPA). The utility filed for bankruptcy in July, after years of underinvestment that yielded a system it called  degraded and unsafe.   Maria is expected to strike the island on Wednesday with winds of up to 160 miles per hour (257 km per hour), the U.S. National Hurricane Center (NHC) said. Irma grazed Puerto Rico, knocking out power to more than 1 million of PREPA s 1.5 million customers, according to the U.S. Energy Department. All but about 60,000 have had power restored, and the island s power plants were not severely damaged.  Maria, however, could be the first major hurricane - defined as Category 3 or higher - to make landfall since Georges in 1998, said Todd Crawford, chief meteorologist at The Weather Company, an IBM company. It could be the first Category 5 since San Felipe II in 1928, which killed more than 300 people on the island.   No generation has seen a hurricane like this since San Felipe II in 1928. This is an unprecedented atmospheric system,  said Puerto Rico Governor Ricardo Rossell , in a statement on Tuesday. The island could be faced with outages for weeks, straining the resources of a utility whose power plants have a median age of 44 years, compared with an industry average of 18 years, and more frequent power outages. PREPA said in a draft fiscal plan released in April that  years of underinvestment have led to severe degradation of infrastructure.    Even if we had an energy system in prime condition, which we all know we don t have, it still would be very difficult,  said Nydia Suarez, who works at CNE Group, a think tank, and lives on the island. She plans to stay with her son in Guaynabo, which is farther inland than her home in San Juan. The utility had to declare bankruptcy in July due to a $9 billion hole deepened by a lengthy recession on the island, inconsistent management and ineffective collections.  The island s power prices are already higher than any U.S. state other than Hawaii, according to the U.S. Energy Department.   They have been reluctant to raise rates to generate additional revenues to increase capital expenditures on the island ... because the population is a bit depressed,  said Rick Donner, vice president and senior credit officer at credit rating agency Moody s Investors Service in New York.     PREPA will use the same plan it used for Irma, Executive Director Ricardo Ramos said in a news release, by first energizing hospitals, water plants and some industries.  The utility said it has refilled all fuel tanks while workers collect debris and trim trees damaged by Irma near transmission lines.  The Department of Energy said it was working with the American Public Power Authority (APPA), PREPA and the Federal Emergency Management Agency (FEMA) to get mutual aid workers to Puerto Rico and elsewhere.  I was 12 days without electricity after Georges. We think about that and with a power system that is worse than it was then   more fragile   we re expecting more time without power,  CNE Group s Suarez said. 
Puerto Rico power grid faces generational threat in Hurricane Maria