No abstract

As competitive market for gas transmission becomes more and more dynamic and we face an increase of regulatory agencies influence, the pressure on cutting down cost of service without affecting reliability and safety is a consequence. Notwithstanding this trend, transportation companies must act in a way that guarantees a fair return on investment and optimizes assets and operation costs. Contractual obligations play an important role since most of the contractual capacity is on a firm basis and subject to liabilities related to capacity shortage or interruption. Compressor stations availability study play a fundamental role in providing information that will support decision making in terms of defining a criterion for installing stand-by units. This paper presents two methods adopted for the Bolivia-Brazil Gas Pipeline Project: (1) Monte Carlo Simulation and (2) Scheduled and Unscheduled Maintenance. A technical end economic feasibility study is also presented to support the decision of installing stand-by units.

Gas pipeline projects are capital intensive and normally are developed under scenarios of uncertainty. Such uncertainties vary from closing take-or-pay, ship-or-pay or delivery-or-pay agreements to those uncertainties related to the acquisition of equipments, material and construction and assembling contracts. Natural gas compression service contracts with compressor station using gas motors and reciprocating compressors have been widely adopted at PETROBRAS as economically feasible against holding the stations as part of the pipeline asset as well as providing an effective approach to mitigate risks inherent to the gas business and associated to the compressor stations. Although compression service contracts with turbo compressors (gas turbine drivers and centrifugal compressors) have not yet been accomplished at PETROBRAS for gas pipeline projects, studies and preliminaries discussions shows that, taken into consideration certain relevant aspects, they will also present great opportunity to be adopted and will generate the same advantages already perceived for the compression service contracts with stations that uses gas motor drivers and reciprocation compressors. This paper has the objective of presenting an economic approach and a business model addressing the main points that must be considered while doing feasibility analysis between the alternatives of holding property of the compression station asset against the opportunity of having a compression service contract as operating cost for the project. Questions such as how to address depreciation, overhaul costs and tailor made equipment, such as centrifugal compressors, are raised and answered.