Technology Innovation to Accelerate Energy Transitions Annex B

been commercialised for methanol-to-olefin production, which employs a silverimpregnated zeolite catalyst.

Read more about this innovation gap (www.iea.org/innovation).

Cement

Technology innovation will be crucial to reduce cement subsector emissions, particularly process emissions for which commercially available mitigation options are relatively limited. CCUS can play a key role, with post-combustion chemical absorption carbon capture currently the most advanced technology. Other capture options under development include oxy-fuel capture, membrane CO2 separation and calcium looping.

Processes are also being developed to utilise captured CO2 for inert carbonate materials in concrete aggregates. Alternative cement constituents, which can be blended into cement to replace a portion of the clinker, require further deployment. R&D is needed on alternative binding materials that rely on raw materials or mixes different from those of OPC clinker, and in many cases result in lower emissions.

Of the various alternative binding materials under development, belite calcium sulphoaluminate (BCSA) shows particular promise in terms of a reasonable balance between remaining technical hurdles and CO2 emissions reduction potential.

Ammonia production using electrolytic hydrogen

This process route could avoid generating CO2 emissions in ammonia production if renewable electricity is used for hydrogen production.

Technology principles: Ammonia production involves combining nitrogen with hydrogen in the Haber-Bosch process. Hydrogen can be produced either through steam reforming (with natural gas as the feedstock) or through electrolysis (with electricity as the feedstock). Hydrogen produced by electrolysis is often referred to as electrolytic hydrogen.

Methanol production using electrolytic hydrogen and CO2

This production route could avoid direct fossil fuel use in methanol production if renewable electricity is employed for hydrogen production and CO2 can be obtained from either biogenic sources or unavoidable industrial sources. In the short to medium term, fossil-based and otherwise avoidable emissions can also be used. In a strong decarbonisation scenario, unavoidable CO2 emissions from fossil-based industrial by-products would become scarce in the long term, so extracting it from the atmosphere through biomass cultivation or air capture would become increasingly important.

Technology principles: Methanol production requires creation of a syngas composed of CO, CO2 and hydrogen gas. A wide variety of feedstocks can be used to produce the syngas: natural gas and coal are currently the most common, but biomass and waste can also be used. It can also be made from a combination of hydrogen (produced by natural gas-based steam reforming or electricity-based electrolysis) and waste CO2 from industrial processes.

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