Puerto Rico’s power grid is “in much better condition” than before Hurricane Maria wiped out an already crippled energy system in September, a top Army Corps of Engineers official said Wednesday.

“It is no secret the grid was in very poor condition before the storm,” said Charles Alexander, director of contingency operations and homeland security headquarters at the Army Corps, in testimony before the House Energy and Commerce Committee. “It is in much better condition today. The reality is, we have put in place new transmission, new distribution lines, new towers, new poles, and other power generation equipment."

But Alexander acknowledged that nearly 50,000 customers remain without power on the island, and he would not say definitively if all Puerto Ricans would have their lights back on by the scheduled end of the Corps’ recovery mission on May 18.

"It is not the resilient grid we all recognize is needed," Alexander said. "We are going to do everything possible to get to as close to 100 percent [power restoration] as possible.”

Alexander noted the areas without power are remote, with much of the work accessible only by helicopter.

The Federal Emergency Management Agency oversees disaster relief efforts on the island, working with the Army Corps, Department of Energy, and the Puerto Rico Electric Power Authority.

Last week, the Army Corps announced it was sending more personnel and equipment to Puerto Rico to help rebuild the grid after FEMA sent another $140 million, extending a $510 million contract.

Hurricane Maria caused an estimated $90 billion in damage in Puerto Rico and the U.S. Virgin Islands, the National Hurricane Center said Monday, making it the third-costliest hurricane in U.S. history behind Katrina and Harvey.

The energy industry, other stakeholders, and many lawmakers are aiming to turn disaster caused by Hurricane Maria into opportunity, proposing a long-term reimagining of Puerto Rico's electricity grid by incorporating renewables and cutting-edge technologies such as microgrids.

A microgrid is generally installed to power a single site or small group of structures that share a common owner, such as a hospital or school system.

Rep. Frank Pallone of New Jersey, the top Democrat on the committee, said Wednesday that he’s concerned U.S. government agencies aren’t doing enough to rebuild the grid stronger.

“While restoring power quickly is the most urgent concern, significant improvements to Puerto Rico’s electrical infrastructure will be needed to build a resilient and modernized grid,” Pallone said. “Replacing the old grid as it stood before the storms will cost taxpayers more money and do nothing to make electricity in Puerto Rico more reliable or affordable. There will be more major storms in the future, and this old grid is simply not up to the task of withstanding those storms."

FEMA and Army Corps officials say meeting those ambitions is challenging because of the Stafford Act, a federal law that requires buildings and other infrastructure to be restored to their original state after a disaster.

“There is a lot of work to do, and the book is not written on the unique opportunity we have to recover Puerto Rico in a more resilient fashion,” said Jeffrey Byard, FEMA's associate administrator of the office of response and recovery, in testimony before the committee.

Puerto Rico’s power grid faced deep-rooted problems even before Hurricane Maria.

The Puerto Rico Electric Power Authority, or PREPA, the sole electricity provider to the island, filed for bankruptcy in July.

PREPA's power plants are 44 years old on average, compared to the industry-wide average of 18 years.

Puerto Rico gets most of its power from Venezuelan oil, and PREPA relied on selling bonds to pay for the imported oil it burned at its aging power plants, which need billions of dollars worth of repairs. Only 2 percent of Puerto Rico’s power before the storm came from renewable energy.

Sensitive to price shocks in the oil market, PREPA charges the island's residents high rates, more than any U.S. state but Hawaii, according to the Energy Information Administration.

The House Natural Resources Committee is investigating accusations of corruption against PREPA based on reports that some of the utility’s employees resorted to bribery and favoritism when restoring power.

Puerto Rico Gov. Ricardo Rossello recently said he wants PREPA privatized to cut costs and attract capital. Pallone on Wednesday said he supports that effort.

“As we consider ideas for strengthening Puerto Rico’s grid, we must contemplate alternatives to PREPA for overseeing the rebuilding and operation of the grid,” he said. “All ideas, from direct privatization to creation of a new, federal power marketing administration should be considered.”