BELGRADE (Serbia), February 6 (SeeNews) – U.S. hi-tech natural gas solutions provider Energtek said its Serbian unit, Pan Energy, has successfully concluded its first year of a revenue-generating natural gas delivery and supply project near Belgrade. Energtek launched this relatively small commercial pilot over a year ago to prove its business model of leveraging its mobile transportation technologies in order to sell ongoing quantities of natural gas, the U.S. company said in a statement last week.