Explorers tried and failed for decades to find oil in Namibian waters until TotalEnergies and Shell announced major discoveries last year.

More rigs raced to the coastline as reserve estimates climbed to 11 billion barrels of crude. With some touting it as the biggest-ever deepwater find, it holds the promise of enormous riches for the southern African nation of 2.7 million people.

Experiences from elsewhere on the continent show caution is warranted.

Neighboring Angola has seen crude sales largely line the pockets of a tiny elite, while graft in Mozambique stemmed from borrowing against gas discoveries before they were even developed. The industry in Nigeria left the Niger delta with oil spills that have made it one of the earth’s most polluted areas, while doing little to alleviate the poverty of local communities.

In Namibia, the cracks are already showing: there have been allegations of graft at Namcor, the nascent state oil company, while an Afrobarometer study shows confidence in the government has waned.

If the projects do go ahead — Total and Shell need to determine the commercial viability of the discoveries and the latest well drilled was a dud — there is another challenge: racing against the energy transition to get oil flowing before global demand turns.

Still, excitement is running high, and successfully developing just the initial oil finds holds the potential to double the size of Namibia’s $12.6 billion economy by 2040.