Gas Top



GasTop/GasPal  As is illustrated, the basic storage reservoir operation consists of adding to inventory and withdrawing for sales.

Classic Storage

Rate of injection and withdrawal are governed by reservoir deliverability and compressor size (HP). Size of inventory on a cycle is determined by Vp and the change in pressure from cushion to peak; the latter is limited by formation parting pressure. Both GasTop and GasPal are configured to compute this bi-directional flow required to analyze gas storage operations.



(Gas Storage Optimization) has optimization and operational modes. As is illustrated, GasTop considers one or more reservoirs flowing through one or more compressors. Each reservoir is a ‘tank type’ container that may be connected to an active aquifer.


Optimization Mode

As the queries highlight, designing a gas storage system is a complex problem. The objective is to find the optimal economic balance of three determinants of performance:

1.     Volume of each reservoir’s cushion gas,

2.     Number of wells in each reservoir, and

3.     HP at each station.

GasTop image16

Using a gas reservoir simulator and an auxiliary economic evaluation program, an engineer can test various combinations and select the one that gives the best result. GasTop automates this selection process via a systematic search of the possible range of each determinant. Given aset of values, GasTop calculates injection & withdrawal rates using a calibrated model of each reservoir and built-in compressor models.


These rates it feeds into its economic routine. This evaluates revenues and costs and calculates NPV for the set. Revenue predictions conform to the way a California storage operator prices its services. The search routine varies the set values to find the optimal combination that

Operational Mode-

GasTop forecasts performances of an existing gas storage system using hourly or daily time steps. With hourly time steps forecasts span a month and with daily time steps a year. For a study of final blowdown of gas storage in a equilibri um between free gas and solution gas and pressure-dependent permeability (to approximate liquid buildup in the formation aroundthe wellbore). “Analysis and Opitimal Design of Gas Storage Reservoirs”, Chang, SPE84822 (2003)






(Software is for unlimited ownership of purchased version. Annual Maintenance is for improvements, access to latest versions, fixing any bugs, plus 24 hour help on a problem encountered)



When you first buy your software, we recommend your software users be trained immediately.

Contact Me If You Need Further Information Or Wish To Place An Order:

Loy Combs          

Loy Combs
Communications Coordinator