Abstract: A method for liquefaction of natural gas using refrigeration from a combination of sources including a refrigeration cycle and letdown energy of natural gas is provided. The natural gas to be liquefied (LNG) is boosted in pressure using a booster that is powered by expansion of a portion of the natural gas flow from the booster through a first natural gas turbine. A second flow of natural gas is expanded in a second natural gas turbine, and the resulting expanded stream, along with the natural gas expanded in the first natural gas turbine, are warmed against the natural gas to be liquefied. The flow rate of the natural gas in the second natural gas turbine is decoupled from the booster, thereby allowing for variation in flow rates and pressures while maintaining a constant production of LNG.