Large natural gas reserves are a great potential economic advantage for Iran's economy. As long as the consumption and production of the natural gas increase in the country, gas industry will play a vital role in meeting oil industry's needs. This paper aims to investigate optimal usage of the Iranian natural gas reserves among different applications and also opportunity cost of allocations by developing the gas industry over a long time horizon. Using welfare function, nonlinear dynamic model is applied to solve the problem of gas allocation among alternatives such as domestic consumption, gas injection, gas exports or gas salvaging using the data over the period 2006-2031. The constraints include gas production, requirements of gas injection, domestic growth, gas consumption and other effective variables and parameters related to the natural gas reserves allocation.
Findings confirm that priorities and the values of optimal allocation gas depend on the constraints of natural gas production, energy policy, target of injection for preservation or increasing the pressure of oil reservoirs and gas imports. Furthermore, low discount rate gas injection has an absolute priority to gas exports. In the baseline scenario, if domestic gas consumption continuously growth at its average rate of last 11 years performance, it won't be possible to allocate gas injection according to the preservation pressure of oil reservoirs scenario and gas exports. The results of optimal gas salvage and its shadow price shows that the lack of gas production ability has a very high opportunity cost at the beginning years.