Solar companies are banding together to help restore electricity to parts of storm-ravaged Puerto Rico as 90 percent of the island's 3.5 million residents remain without power.

Solar supplies such as roofing, generators and lighting equipment worth about $2 million are expected to arrive in the territory in the coming weeks.

Most of that aid is coming from a national solar industry group, which is sending a plane to Puerto Rico with $1.2 million in supplies donated by its members. The Solar Energy Industries Association is "putting together people that have product with people that have money," the group's president, Abigail Ross Hopper, told CNBC.

More aid is coming from a new group called Light Up Puerto Rico that was formed in the days after Hurricane Maria tore through the island. Light Up Puerto Rico will send about $700,000 in supplies by Oct. 15, the group said. Light Up Puerto Rico is led by two Puerto Ricans, Jorge and Carilu Alvarado, whose local connections will allow the group to distribute aid efficiently, according to Jarem Hallows, who is working with the organization.

Hopper said solar will be particularly useful in Puerto Rico because it can begin powering homes and businesses before the territory is able to rebuild its electric grid, a project that could take months. In the meantime, solar generators can serve as a stop gap that won't require costly diesel.

"Everything is needed down there, but we are trying to help out in a unique way," said Brad Creer, president of New Star Solar.

Creer is working with Light Up Puerto Rico and Tifie Humanitarian, a nonprofit, to provide solar equipment for rural areas of the island, such as Aguas Buenas, Salinas, Naranjito, Aguadilla, Las Marias and Mayaguez.

The effort to bring solar supplies to Puerto Rico is bringing together companies that are traditional competitors, such as Vivint Solar and Sunrun. While in normal times the two companies compete for market share, the crisis in Puerto Rico created an opportunity for the two national solar providers to cooperate.

For instance, after Sunrun pledged more than 8,000 pounds of solar products but did not have the capacity to bring the materials to Puerto Rico securely, Vivint volunteered to get the shipment into San Juan, according to emails between Light Up Puerto Rico members and the companies, provided by Hallows. A spokesperson for Sunrun said that none of the details have been finalized, and the company is now working with another nonprofit, not Vivint.

"That's what's great to see: They're getting together; we are putting all our competition aside to do this," Creer said.

Tesla CEO Elon Musk, a solar entrepreneur better known for his work on electric vehicles and spacecraft, has also jumped into the fray, posting a message to his Twitter account Oct. 5 saying it would be feasible for Tesla to rebuild Puerto Rico's electric grid.

Puerto Rico Gov. Ricardo Rossello responded on the platform by saying that Puerto Rico could be Tesla's "flagship project." At a press conference the next day, Rossello said he was "very serious" about considering new, innovative technology.



Rossello Tweet

Tesla has built electric systems on other islands such as Kauai and American Samoa, though those projects were built for far smaller populations than Puerto Rico. Last November, Tesla purchased solar company SolarCity for $2 billion. Musk later unveiled a new solar rooftop project the entrepreneur said would make solar roofs that are comparable in cost to nonsolar roofs.

In addition to being a humanitarian project, the work that solar companies are doing in Puerto Rico could serve as a case study for further projects. Hopper said the destruction of Puerto Rico's electric grid means there is an opportunity to reimagine what an electric grid can look like.

"The devastation of the grid there means we can rebuild the way people actually use electricity as opposed to what we've always done," she said.

Lynn Jurich, the CEO of Sunrun, said in a statement that the company would work to build "a more resilient, reliable distributed energy infrastructure."

"Rooftop solar paired with batteries is a scale-able, cost-effective option and capable of strengthening electric grids worldwide, especially in remote island regions," Jurich said.

An increase in the amount of renewable energy produced in Puerto Rico could theoretically reduce the amount Puerto Ricans pay for electricity by a dramatic amount. Three-quarters of the energy consumed in Puerto Rico is produced by petroleum products, according to government data, and all of that petroleum is imported. The only state whose residents pay more for electricity is Hawaii, which has set a goal for its utilities of 100 percent renewable energy by 2045.

Nonetheless, building out a full-scale solar infrastructure would be expensive. One clean-energy think tank cited by Bloomberg put the tally at $250 million for 90 megawatts of solar across several Caribbean islands — about 1 percent of the energy that would be needed to power all of Puerto Rico's 1.2 million households.