Eesti Energia AS is a public limited energy company in Estonia with its headquarters in Tallinn. It is the world's biggest oil shale to energy company. The company was founded in 1939.  As of 2014, it operates in Estonia, Latvia, Lithuania, Finland, Jordan and Utah, United States.

In Estonia the company operates under the name Eesti Energia, while using the brand name Enefit for international operations. 

The main raw material for energy production – oil shale – is extracted from mines located in Eastern-Estonia and owned by the company. The group of Eesti Energia has three main operation areas: electricity generation, shale oil production, and sale and distribution electricity.

Its shares are owned by the Government of Estonia. Eesti Energia produces and sells electricity, heat and fuel (oil shale and shale oil) and provides customer and consulting services. The company is engaged in the oil shale mining through its subsidiary Enefit Kaevandused, which extracts oil shale by opencast mining in the Narva quarry and by underground mining in the Estonia mine.

According to en.wikipedia