Power‐to‐Syngas: An Enabling Technology for the Transition of the Energy System?

Abstract

Power-to-X concepts promise a reduction of greenhouse gas emissions simultaneously guaranteeing a safe energy supply even at high share of renewable power generation, thus becoming a cornerstone of a sustainable energy system. Power-to-syngas, that is, the electrochemical conversion of steam and carbon dioxide with the use of renewably generated electricity to syngas for the production of synfuels and high-value chemicals, offers an efficient technology to couple different energy-intense sectors, such as "traffic and transportation" and "chemical industry". Syngas produced by co-electrolysis can thus be regarded as a key-enabling step for a transition of the energy system, which offers additionally features of CO -valorization and closed carbon cycles. Here, we discuss advantages and current limitations of low- and high-temperature co-electrolysis. Advances in both fundamental understanding of the basic reaction schemes and stable high-performance materials are essential to further promote co-electrolysis.

Highly Efficient Porous Carbon Electrocatalyst with Controllable N‐Species Content for Selective CO2 Reduction

“…Converting CO 2 into useful fuels and chemicals via renewable energy sources is attracting increasing attention in an attempt to mitigate resource extraction and lower the carbon footprint . Among various strategies, electrochemical CO 2 reduction reaction (CO 2 RR) powered by renewable electricity represents one of the most promising approaches to achieve the carbon‐neutral cycle.…”

Zn–Cu Alloy Nanofoams as Efficient Catalysts for the Reduction of CO2 to Syngas Mixtures with a Potential‐Independent H2/CO Ratio

“…Syngas can be used to produce hydrocarbons and alcohols through well‐established industrial technologies. A two‐step process that couples CO 2 electroreduction to syngas with its subsequent transformation to high value‐added products has been proposed to be more favorable from an economic perspective because the reduction of CO 2 to CO occurs at moderate overpotentials and a highly energy‐demanding product separation step is not required . However, one of the main prerequisites for the syngas that is generated is control over the H 2 /CO ratio, which must meet different values depending on the reaction targeted: optimal H 2 /CO ratios of 1.5–2.2 are typically required for methanol synthesis and the Fischer–Tropsch reaction; a H 2 /CO ratio of 3 is required for the methanation reaction; and a H 2 /CO ratio of 1 is typically required for hydroformylation and fine chemical synthesis …”

“…Fossil‐fuel reforming reactions are currently the largest source of syngas; however these processes generate specific H 2 /CO ratios (Figure ) and are based on nonrenewable feedstocks. Adjusting these ratios requires an additional energy‐demanding water‐gas‐shift reaction . In this context, electrochemical syngas generation is a more versatile and sustainable alternative, allowing a broad range of H 2 /CO ratios to be produced from renewable precursors (H 2 O and CO 2 ) .…”

Development of a Structured Reactor System for CO2 Methanation under Dynamic Operating Conditions

“…Several energy storage technologies exist that can be used to provide energy on demand from fluctuating sources. Next to batteries, capacitors or thermal storage systems such as Power‐to‐X (PtX) processes are of special interest in this context …”