Carbon-neutral hydrogen production from natural gas via electrified steam reforming: Techno-economic-environmental perspective

Abstract

This study proposes and evaluates a novel carbon-neutral hydrogen (H2) production process from natural gas through electrified steam methane reforming (e-SMR) with renewable electricity. The process model consists of different unit technologies such as reforming, water–gas shift, hydrogen pressure swing adsorption, and CO2 capture, along with heat recovery. Then, we evaluated the techno-economic-environmental performance of the proposed e-SMR process by comparing it with the conventional fired-heating steam methane reforming (f-SMR). By employing an electrically driven reformer using renewable energy, e-SMR outperforms f-SMR with less natural gas consumption, higher energy efficiency of 78.7%, and lower net CO2eq emission of 5.28 kg CO2eq/kg H2 and captured 5.58 kg CO2/kg H2; however, it has a drawback, i.e., higher H2 unit production cost (UPC) of 3.49 $/kg with a capacity of 7.06 ton/day. Sensitivity and uncertainty analyses identified the major cost drivers of UPC, such as the prices of natural gas, renewable electricity, and interest rates, as well as economic risks and uncertainties. The economic viability of e-SMR was determined by investigating multiple plant capacities, natural gas markets, renewable energy prices, and possible future CO2 selling prices. According to the investigation, currently, the US and India show promise for e-SMR, with abundant and affordable natural gas and renewable energy resources, both priced at around 3.49 $/kg of H2, respectively. Furthermore, the global 2030's scenario with 45 $/MWh of renewable electricity, and capture CO2 credit of 35 $/ton is observed at 3.40 $/kg H2, compared with that of 2050 at 2.91 $/kg H2. e-SMR is well adaptable to many countries' energy mix because it is flexible to utilize hybrid primary energy input, conventional natural gas as feedstock, and conventional/renewable energy for utilities.