Reduction of carbon intensity of electrification by reservoir-to-wire integration with CO₂ capture and storage: conceptual design and analysis

The energy transition to a low-carbon economy involves adoption of cleaner production and energy technologies while the global energy demand continues to rise. Low-emission gas-to-wire firing low-quality natural gas from deep-water offshore fields emerges as a solution that can accelerate the energy transition without compromising energy and environment securities. The present work considers an innovative design of low-emission floating gas-to-wire co-firing CO₂-rich natural gas and blue-H₂ (NG-H₂-GTW-CCS) and evaluates it against a conventional low-emission gas-to-wire (NG-GTW-CCS) firing only CO₂-rich natural gas. Both alternatives implement capture and geological storage of CO₂ in the oil reservoir for enhanced oil recovery. The NG-H₂-GTW-CCS sends part of the CO₂-rich natural gas feed to dry autothermal reforming coupled to pre-combustion carbon capture, producing blue-H₂ and co-firing it with CO₂-rich natural gas. The sustainability assessment follows TOPSIS method (technique for order of preference by similarity to ideal solution) through process simulation. Results show that NG-GTW-CCS achieves a net power of 525.58 MW, while NG-H₂-GTW-CCS achieves 524.67, 541.77, and 591.24 MW with blue-H₂ at, respectively, 10%mol, 30%mol, and 50%mol in the fuel-blend. The net present value of NG-GTW-CCS is 2666.3 MMUSD while NG-H₂-GTW-CCS reaches 2000.2, 2253.3, and 2412.0 MMUSD (at 10%mol, 30%mol, and 50%mol blue-H₂). It is shown that the sustainability degree of process alternatives co-firing blue-H₂ outperform the conventional NG-GTW-CCS counterpart.