The cost of producing “green” methanol ( vs. fossil production) based on renewable energy, H ₂ and CO ₂ is presented.

The production of energy carriers based on renewable electricity via the Power-to-X (PtX) approach holds the key for a holistic transformation of our global industries from fossil fuels towards renewable energy sources. To compete with cheap fossils, PtX products demand energy-efficient processes and low-cost renewable electricity. Therefore, the import of PtX products from countries with high renewable energy potentials to countries with high energy demand presents a promising pathway. However, the question which set of PtX products qualifies as suitable for long-distance transport has not yet been answered. In this context, this paper assesses the energy and cost efficiency of five PtX energy carriers (methane, methanol, ammonia, liquefied hydrogen and hydrogen bound in LOHC). Furthermore, we evaluate the influence of fluctuating renewables, availability of water and transport distance in a case study for large-scale PtX production in Morocco. Our results show that the evaluated PtX pathway efficiencies vary between 40–52% (base cases) and 44–58% (optimistic cases). None of the pathways assessed is significantly affected in its overall efficiency by a ship transport over an exemplary distance of 4000 km. However, for longer transport distances the cost difference between the assessed pathways increases. The production cost of the PtX energy carriers (124–156 € per MWh) depends on the availability of excess heat, energy density of the product and, if required, liquefaction efforts. In summary, the paper reveals that the long-distance transport and import of PtX products present an interesting option for the ongoing integration of renewable electricity into our energy system and industries. The petrochemical and steel industries in particular, as well as heavy goods transport, shipping and aviation, will be highly dependent on these imported synthetic energy sources.

In this study, a holistic well-to-wheel (WtW) life cycle assessment of the production and utilization of short oligomers of OME _3–5 as produced via a Power-to-Liquid (PtL) pathway has been conducted.

Long-term transition pathways to a low-carbon energy system are analysed by applying the energy system model REMod. All in all, the paper contributes to the current research through an innovative scenario approach, using assumptions for societal trends and quantitative results for scenarios, analysing the paths towards climate neutrality and defossilization in 2050. In the case study of Germany, these trends and drivers influence the results and the technology composition in each consumption sector (buildings, transport, and industry). Across all scenarios, it can be observed that the electrification of all sectors is important for the defossilization of the energy system, as the direct use of electricity from renewable energy is more efficient than the consumption of carbon-neutral synthetic energy carriers. However, different consumer behavior (e.g., non-acceptance or resistance against specific technologies) influences not only the efficient use of (green) electricity, it also changes the optimal pathways of the transition to paths with greater efforts. One potential societal trend—sufficiency—could be an important cornerstone for reaching the targets, as the required expansion and exchange of technologies are lower and thus facilitate the transition.