• Energy Research
• 13. Climate action close

This work proposes an innovative method for adjusting the natural gas from the grid to the consumer pipeline requirements in a full-scale pressure reduction station. The use of two counterflow vortex tubes instead of the traditional boiler to preheat the gas before throttling is demonstrated as a powerful alternative. Thus, a reduction of fossil fuel consumption is reached, which amounts to 7.1% less CO2 emitted. To ensure the optimal configuration, the vortex tube was thoroughly characterized in laboratory facilities using nitrogen as the working fluid. Various operating conditions were tested to determine the most efficient setup. Computational Fluid Dynamics (CFD) simulations were conducted with nitrogen to validate the behavior of the vortex tube. Subsequently, the working fluid was switched to methane to assess the performance differences between the two gases. Finally, the vortex tubes were deployed at a full-scale installation and tested under real consumption demand. The results obtained from this study offer promising insights into the practical implementation of the proposed method for adjusting the natural gas flow, highlighting its potential for reducing fossil fuel consumption and minimizing CO2 emissions. Further improvements and refinements can be made based on these findings.

This commentary provides insights on present and future trends concerning the carbon footprint (CF) of liquid-electrolyte lithium-ion batteries (LIB). While the focus of the battery industry and policymakers was previously on reducing the cost of LIB and their usage reducing CO2 emissions through e-mobility and the integration of more renewables into the energy mix, there is now an increasing focus on reducing the CF of LIB themselves. The production of LIB is highly material- and energy-intensive, resulting in high embedded CO2 emissions. Efforts to reduce the CF of LIB require strong interaction between battery producers, users, and policymakers. Policymakers are instrumental in shaping and regulating the market, while the battery industry can leverage low CF batteries as a unique selling proposition. We categorize current and future CF trends according to the three stakeholder groups, and for the battery industry stakeholder group, we further distinguish between high-level, product, and process trends. Next Energy, 1 (2) ISSN:2949-821X

This think piece discusses current barriers to the rapid decarbonization of transport and ways to overcome them. Policymakers face a set of contradictory goals, leading them to ponder only incremental measures: The need to reduce carbon emissions conflicts with accessibility improvements and the resulting induced traffic. At the same time, the prevention of urban sprawl as a means of promoting sustainable mobility is fundamentally thwarted by technical advances in electric cars and autonomous driving. Unable to attract public acceptance for measures that would effectively reduce travel demand, transport policy is failing to provide convincing transition pathways toward sustainable and equitable mobility for growing urban populations. As a possible way forward, we propose a new starting point for transport policy discussions, exploring the feasibility of urban transport systems based on sustainable, flexible, and relatively cheap modes of active mobility – the E-Bike City. This paper aims to outline a research agenda for testing the effects of such a policy direction. In contrast to the literature on “cycling cities”, this effort should include possibilities newly opened by the recent availability of electric micro-mobility vehicles. Also, it should aim for a balanced and realistic transition rather than a unimodal utopia. Inspired by friendly conversations around recent urban visions like 15-Minute Cities or Superblocks, this paper is meant to begin a new discussion about alternative future directions for transport policy beyond mere optimization and technical incrementalism. Journal of Transport Geography, 111 ISSN:0966-6923 ISSN:1873-1236

Analysis of how will Kenya’s energy mix, emissions, and overall systems costs evolve if the country were to mandate that 100% of the transportation sector be electrified by 2040

The possibility to employ alternative fuels is gaining special interest in the marine sector. There are several suitable candidates for traditional fossil fuels substitution. Among them, ammonia is a promising solution that allows progress on decarbonization since the ammonia molecule does not contain carbon. Hence, the present work analyzes the use of ammonia as a potential fuel for a marine engine. Particularly, a dual fuel mode ammonia/diesel oil operation is proposed. As expected, the carbon dioxide emissions are reduced as the proportion of ammonia is increased. Nevertheless, other non-desirable substances are generated such as non-reacted ammonia, NOx and N2O. Due to these opposing effects, a multi-criteria analysis is proposed to characterize the most appropriate proportion of ammonia in the fuel. The environmental damage of the different pollutants was considered. Due to the important environmental adverse effects of NOx and N2O, only a maximum 20% ammonia percentage on the fuel was obtained as the most appropriate option. A higher ammonia content leads to excessive concentrations of NOx and N2O being emitted to the environment.

Concentrating solar power (CSP) with thermal storage can help integrate the increasing amounts of intermittent renewables in China and the US. An interconnected fleet of CSP stations in the deserts of China and the US can supply fully dispatchable or baseload electricity for the demand centers, via long-distance HVDC lines. In China the solar power cost at the point of delivery is at or below 20 $c/kWh, if the CSP fleet utilizes the solar resources in Tibet. In the US regional weather patterns make it economically unfeasible, although technically possible, to generate fully dispatchable CSP. European Geosciences Union General Assembly 2015 - Division Energy, Resources and Environment, EGU 2015 Energy Procedia, 76 ISSN:1876-6102

Out of 2 TWe of coal power plant capacity in operation globally today, more than half is less than 14 years old. Climate policy related to limiting CO2-emissions makes the longer-term operation of these plants untenable. In this study, we assess the spectrum of available options for the future of both equipment and jobs in the coal power sector by assessing the full scope of “retrofit decarbonization” options. Retrofit decarbonization is an umbrella term that includes adding carbon capture, fuel conversion, and the replacement of coal boilers with new low-carbon energy sources, in each case re-using as much of the existing equipment as economically practicable while reducing or eliminating emissions. This article explores this idea using the Polish coal power fleet as a case study. Retrofit decarbonization in Poland was shown to be most attractive using high-temperature small modular nuclear reactors (SMRs) to replace coal boilers, which can lower upfront capital costs by ~28–35% and levelized cost of electricity by 9–28% compared to a greenfield installation. If retrofit decarbonization is implemented globally by the late 2020s, up to 200 billion tons of otherwise-committed CO2-emissions could be avoided.