Eesti Gaas Eesti Gaas is an Estonian energy company. AS, branded internationally as Elenger, is an energy company with headquarters in Tallinn Tallinn, the largest city and capital of Estonia (population 440 000). , Estonia. The company's main activity is selling and distributing natural gas in Estonian, Latvian, Finnish, and Lithuanian markets. Eesti Gaas Eesti Gaas is an Estonian energy company. ' product portfolio includes also LNG, CNG, and electricity, including solar energy. Eesti Gaas Eesti Gaas is an Estonian energy company. was founded in 1865.