Relative Greenhouse Gas Abatement Cost Competitiveness of Biofuels in Germany

Abstract

Transport biofuels derived from biogenic material are used for substituting fossil fuels, thereby abating greenhouse gas (GHG) emissions. Numerous competing conversion options exist to produce biofuels, with differing GHG emissions and costs. In this paper, the analysis and modeling of the long-term development of GHG abatement and relative GHG abatement cost competitiveness between crop-based biofuels in Germany are carried out. Presently dominant conventional biofuels and advanced liquid biofuels were found not to be competitive compared to the substantially higher yielding options available: sugar beet-based ethanol for the short-to medium-term least-cost option and substitute natural gas (SNG) for the medium to long term. The competitiveness of SNG was found to depend highly on the emissions development of the power mix. Silage maize-based biomethane was found competitive on a land area basis, but not on an energetic basis. Due to land limitations, as well as cost and GHG uncertainty, a stronger focus on the land use of crop-based biofuels should be laid out in policy.

Electrofuels from excess renewable electricity at high variable renewable shares: cost, greenhouse gas abatement, carbon use and competition

“…emissions, 32 as well as emissions from vehicle manufacturing and infrastructure are not included. The fuel combustion is assumed to be carbon neutral, as the carbon absorbed during plant growth or carbon capture is emitted, thus closing the short life-cycle.…”

“…Detailed input-output data of all fuel production processes that are included in this study lay the foundation for calculating detailed cost and GHG emissions developments as well as for analysing uncertainties and sensitivities to important parameters. GHG emissions are calculated according to Millinger et al, 32 with inputs multiplied by their respective emission factors (EF). For each process step along the pathway, emissions are allocated to main and by-products according to their relative energy content, if applicable.…”

“…2), while direct and indirect land use change emissions are not. Biomass residues are assumed to carry zero emissions in accordance with RED II, 56 while transport emissions are assumed according to Millinger et al 32 For the life-cycle analysis of the CO 2 inputs, two reference systems are assessed (Fig. 3):…”

“…One nding from the models is that the merit order of the fuels changes over time and strongly depends on the functional unit (e.g. costs per energy unit, 30,31 costs per GHG reduction unit 32 or GHG reduction per agricultural land unit 7 ), so that a methodological breadth of approaches is required to investigate the complexities. 33 For electrofuels, the eld of systems assessment is relatively new, 21 but growing.…”

Incorporating consumer choice into an optimization model for the German heat sector: Effects on projected bioenergy use

“…The approach of the model follows BENOPT (BioENer-gyOPTimisation model), which was developed for biofuels assessments in the transport sector [42][43][44]. The model structure is as follows: the three main sectors of the German heat sector, private household, industry and trade/ commerce are further divided into several sub-sectors, with different properties in terms of demand profiles and infrastructures.…”