Economic analysis of a combined energy–methanol production plant

The large-scale combined production of methanol and electricity from natural gas is simulated and evaluated from an economic point of view. Both capital and operating costs are considered. The proposed solution is based on steam methane reforming and consists of an once-through methanol synthesis followed by a power plant in which the unreacted gases are burned. Electricity is produced in a combined-cycle plant. It is supposed to add the energy production unit to an already existing methanol plant without decreasing the methanol production. The economic analysis shows that, given the low natural gas price in the Saudi Arabia context, the combined production ensures an increased annual revenue that allows a reasonable payout time for the added energy plant.

► A polygeneration plant using natural gas in the Saudi Arabia context is studied.
► Methanol/electricity coproduction is compared with standalone methanol synthesis.
► Plant simulations are performed.
► An economic analysis that takes into account capital and operating costs is made.
► Profitability of the polygeneration solution is shown by payout time evaluation.