The $1.3 billion Kupe Gas Project in Taranaki was officially opened today by Prime Minister John Key.

The gas produced from the field will meet about 15 percent of New Zealand's annual gas demand, and 50 percent of LPG demand, for the next 15 to 20 years.

Energy Minister Gerry Brownlee said Kupe was going to play an important part in New Zealand's energy infrastructure.

"The Taranaki oil and gas industry accounts for almost 90 percent of the sector's nationwide workforce," he said.

"As New Zealand's frontier basins are explored, and our petroleum potential is reached, I look forward to seeing the same regional development in other parts of New Zealand."

Mr Brownlee said it was estimated that about 375 New Zealand companies supplied or provided services to the Kupe project, and the value of orders placed in New Zealand was $620 million.