Analytical Investigation of Compressor Station Energy Efficiency Opportunities on the AKK Pipeline

The Ajaokuta-Kaduna-Kano (AKK) pipeline, Nigeria's largest domestic gas transmission project, features multiple compressor stations that collectively represent a major energy consumption centre with significant efficiency optimisation potential. This study analytically investigates compressor station energy efficiency opportunities along the AKK pipeline, developing an integrated pipeline-compressor simulation model to identify and quantify efficiency improvement scenarios. The research employs a computational engineering analysis methodology, constructing a pipeline hydraulic and thermodynamic model in PIPELINE STUDIO and calibrating it against available commissioning performance data from the Ajaokuta and Abuja booster stations. The study systematically evaluates five categories of efficiency improvement opportunities: compressor unit load optimisation, variable speed drive (VSD) retrofitting on ancillary equipment, waste heat recovery from gas coolers, pipeline inlet pressure optimisation, and compressor scheduling strategies aligned with gas demand patterns. Each opportunity is quantified in terms of fuel gas savings, CO2 emission reduction, and payback period. The study addresses a gap in published literature specific to the energy efficiency of Nigerian gas transmission compressor stations operating under tropical ambient and demand-variable conditions. Findings indicate that combined implementation of the identified efficiency opportunities could reduce AKK compressor station fuel gas consumption by 12 to 18 percent annually, equivalent to significant cost savings at commercial gas prices and substantial scope 1 emission reductions. VSD retrofitting on gas cooler fan drives and compressor scheduling optimisation are identified as the highest-priority, fastest-payback opportunities. Recommendations include incorporation of an energy management system aligned with ISO 50001 in the AKK pipeline operating framework. Keywords: compressor efficiency, AKK pipeline, energy optimisation, fuel gas, gas transmission.