The project, which is run by research firm X, has provided back-up internet services after natural disasters before.
Some of these plans, of course, are more aspirational than others.
Puerto Rico Governor Ricardo Rosello joined the conversation, tweeting to Musk: "Let's talk".
It's unclear if X has found a telecomm company to partner with in the US territory.
Last Thursday, the Project Loon team at Alphabet's X division noted to Mashable that they were "working hard with the Puerto Rican authorities to see if there's a way for us to use Loon balloons to bring some emergency connectivity to the island during this time of need".
With much of Puerto Rico still without power and internet connectivity, Project Loon has gained approval to begin experimental relief efforts. But that doesn't mean it will able to get them in the air anytime soon. The balloons aren't capable of doing that by themselves.
But there are limitations, she said Saturday.
In order to deliver signals to people's devices, Loon has to be integrated with a telco partner's network.
In a statement given to Engadget, a spokesperson for Alphabet's X lab said the team needs to work with a partner network of a local telecom, like Telefonica, to make it all work.
Hundreds of Tesla Powerwall battery systems are already in Puerto Rico and Tesla employees are in the country helping with installation and training for maintenance. The FCC said on Friday that 83 per cent of cell sites remain out of service, while wireless communications company are deploying temporary sites. The island, home to almost 3.5 million people, remains crippled by the Category 4 storm that struck last month, which disabled more than 90 percent of Puerto Rico's cell towers and left its communications infrastructure in shambles.
Tesla's Powerwall renewable energy tech powers smaller islands and its thought that it could be scaled up for Puerto Rico. "You don't have to announce you've lit up coverage".
"They noticed everyone in the plaza pulling their phones out", said CEO Vanu Bose. "People know right away".