Greek energy firm Energean has made a vast discovery of 28-42 billion cubic meters (Bcm) of natural gas at the North Karish field off Israel’s northwest coast, the company said on April 15.

The discovery is located not far from the company’s FPSO unit, which aims for a total export capacity of 8 Bcm per year.

Energean has already presold some of the gas to independent Israeli power producer I.P.M. Beer Tuvia in an agreement set to last 19 years and earn Energean $900 million.

Drilling on the three main development wells for the field will go even deeper to explore for more resources.

Energean, which is listed on both the London and Tel Aviv stock exchanges, is developing the Karish and Tanin natural gas fields. It also has operations in Greece and the Adriatic.