Climate bonds toward achieving net zero emissions and carbon neutrality:Evidence from machine learning technique

The Conference of the Parties(COP26 and 27)placed significant emphasis on climate financing policies with the objective of achieving net zero emissions and carbon neutrality.However,studies on the implementation of this policy proposition are limited.To address this gap in the literature,this study employs machine learning techniques,specifically natural language processing(NLP),to examine 77 climate bond(CB)policies from 32 countries within the context of climate financing.The findings indicate that“sustainability”and“carbon emissions control”are the most outlined policy objectives in these CB policies.Additionally,the study highlights that most CB funds are invested toward energy projects(i.e.,renewable,clean,and efficient initiatives).However,there has been a notable shift in the allocation of CB funds from climate-friendly energy projects to the construction sector between 2015 and 2019.This shift raises concerns about the potential redirection of funds from climate-focused investments to the real estate industry,potentially leading to the greenwashing of climate funds.Furthermore,policy sentiment analysis revealed that a minority of policies hold skeptical views on climate change,which may negatively influence climate actions.Thus,the findings highlight that the effective implementation of CB policies depends on policy goals,objectives,and sentiments.Finally,this study contributes to the literature by employing NLP techniques to understand policy sentiments in climate financing.

A concept to support the transformation from a linear to circular carbon economy:net zero emissions,resource efficiency and conservation through a coupling of the energy,chemical and waste management sectors

Coal and carbon-containing waste are valuable primary and secondary carbon carriers.In the current dominant linear economy,such carbon resources are generally combusted to produce electricity and heat and as a way to resolve a nation’s waste issue.Not only is this a wastage of precious carbon resources,which can be chemically utilized as raw materials for production of other value-added goods,it is also contrary to international efforts to reduce carbon emissions and increase resource efficiency and conservation.This article presents a concept to support the transformation from a linear‘one-way cradle to grave manufacturing model’toward a circular carbon economy.The development of new and sustainable value chains through the utilization of coal and waste as alternative raw materials for the chemical industry via a coupling of the energy,chemical and waste management sectors offers a viable and future-oriented perspective for closing the carbon cycle.Further benefits also include a lowering of the carbon footprint and increasing resource efficiency and conservation of primary carbon resources.In addition,technological innovations and developments that are necessary to support a successful sector coupling will be identified.To illustrate our concept,a case analysis of domestic coal and waste as alternative feedstock to imported crude oil for chemical production in Germany will be presented.Last but not least,challenges posed by path dependency along technological,institutional and human dimensions in the sociotechnical system for a successful transition toward a circular carbon economy will be discussed.

Creation of Zero CO2 Emissions School Buildings Due to Energy Use in Crete-Greece

Decrease of energy consumption in buildings and increase of the share of renewable energies in them are currently technologically and economically feasible and it is promoted by E.U. policies. After 2019, all the new public buildings in EU countries must be near zero energy buildings reducing their energy consumption and CO2 emissions. Use of various renewable energies for heat and power generation in school buildings in Crete-Greece can result in zeroing their fossil fuels consumption and CO2 emissions. Purpose of the current work is to investigate the possibilities of creating zero CO2 emissions school buildings in Crete-Greece due to operational energy use in them. A methodology which allows the replacement of fossil fuels with renewable energies in school buildings is proposed. Solar energy, solid biomass and low enthalpy geothermal energy, which are abundant in Crete, can be used for that. School buildings in Greece consume significantly less energy, 68 KWh/m2 year, and emit less CO2, 28 kgCO2/m2 year, than the corresponding buildings in other countries. The installation cost of renewable energies systems in order to replace all fossil fuels used in school buildings in Crete-Greece and to zero their CO2 consumption due to energy use in them has been estimated at 47.42 - 87.71 €/m2, which corresponds to 1.69 - 3.13 €/kg CO2 saved.

CO_(2) Reduction Request and Future High-Efficiency Zero-Emission Argon Power Cycle Engine

To meet the requirements of strict fuel consumption and emission limits,continuously increasing the thermal efficiency of an internal combustion engine and decreasing its exhaust emissions are the main challenges to its sustainable development within the automotive industry.Considering the competition with other zero-emission powertrain systems,such as vehicle batteries and fuel cells,the development of the internal combustion engine needs to focus on producing higher efficiency and zero emissions to meet the request of CO_(2) reduction.This paper introduces two novel concepts for an internal combustion engine featuring high efficiency and zero emissions.Referred to as the argon power cycle engine fueled with either hydrogen or natural gas within an oxygen–argon mixture,its fundamentals and characteristics are expounded.This includes a method necessary to absorb carbon dioxide when natural gas is used as fuel instead of hydrogen.

A coal-fired power plant integrated with biomass co-firing and CO_(2) capture for zero carbon emission

A promising scheme for coal-fired power plants in which biomass co-firing and carbon dioxide capture technologies are adopted and the low-temperature waste heat from the CO_(2) capture process is recycled to heat the condensed water to achieve zero carbon emission is proposed in this paper.Based on a 660 MW supercritical coal-fired power plant,the thermal performance,emission performance,and economic performance of the proposed scheme are evaluated.In addition,a sensitivity analysis is conducted to show the effects of several key parameters on the performance of the proposed system.The results show that when the biomass mass mixing ratio is 15.40%and the CO_(2) capture rate is 90%,the CO_(2) emission of the coal-fired power plant can reach zero,indicating that the technical route proposed in this paper can indeed achieve zero carbon emission in coal-fired power plants.The net thermal efficiency decreases by 10.31%,due to the huge energy consumption of the CO_(2) capture unit.Besides,the cost of electricity(COE)and the cost of CO_(2) avoided(COA)of the proposed system are 80.37/MWhand41.63/tCO_(2),respectively.The sensitivity analysis demonstrates that with the energy consumption of the reboiler decreasing from 3.22 GJ/tCO_(2) to 2.40 GJ/tCO_(2),the efficiency penalty is reduced to 8.67%.This paper may provide reference for promoting the early realization of carbon neutrality in the power generation industry.

Multiple routes toward engineering efficient cyanobacterial photosynthetic biomanufacturing technologies

Developing efficient CO_(2)utilization technologies can alleviate the urgent pressure on energy and the environment.Moreover,these technologies are crucial for achieving the goal of net zero emissions.Microalgae are photoautotrophic microorganisms that are the main sources of primary productivity in the biosphere.Cyanobacteria,the only prokaryotic microalgae,have also been considered as promising chassis for photosynthetic biosynthesis,directly converting solar energy and CO_(2)into various bio-based products.This technological route is called photosynthetic biomanufacturing,and is advantageous to simultaneous carbon fixation and clean production.This review focuses on development mode,application and suggests trends related to the further development of photosynthetic biomanufacturing.With regard to the link between photosynthetic CO_(2)fixation and the production of desired metabolites,we summarized and compared three widely adopted strategies.“Screening to find”,screening a large number of high-quality cyanobacterial resources and analyzing their intracellular metabolites are of significance for screening novel cyanobacterial species with high-value chemicals and properties of industrial relevance.“Engineering to modify”,the emergence and application of synthetic biological tools and metabolic engineering strategies have enhanced the ability to modify different cyanobacterial species to reshape more carbon to flow toward synthetic tailored chemicals.“Stressing to activate”,through special culture conditions and strategies,combined with omics analysis techniques,silent metabolic pathways and functional modules are activated to induce the accumulation of high-value chemicals.This review provides valid and updated information to facilitate the development of photosynthetic biosynthesis route with carbon fixation and clean production,providing specific feasible solutions for net zero emissions.

Green chemistry of chromate cleaner production

Research topics and methods of green chemistry in chromate production are introduced in this paper. New original green chemical process of the heterogeneous reaction and separation system of liquid phase oxidation of chromite in molten salt of sodium hydroxide—one way separation in high concentration medium—metastable phase separation—carbonate recycle conversion has been developed. The green commercial process for comprehensive utilization of mineral resources—reactant recycle inside the process—zero emission was established.

A theory of carbon currency

We propose a new international monetary system based on carbon currency(the carbon standard)to tackle two pressing externalities in today’s global economic and political context:the dangerous and irreversible effects caused by unconstrained green-house gas emissions and the cost to the rest of the world as a result of the U.S.dollar being the dominated global currency and the U.S.Federal Reserve increasingly implementing monetary policies not aligned with the global common interest.We define carbon currency as standardized carbon-related securities backed up by the right of one unit of carbon emissions.It can be used as a new global reserve currency and functions as an international unit of account.Through the trading of carbon currency,efficient carbon prices are established.By incorporating the cost of carbon emissions into decision making,carbon pricing provides incentives for countries to pursue low-carbon growth,which helps achieve the net zero emissions global goal set under the 2015 Paris Agreement.Under the carbon standard,the external shocks to the international financial system would come from variations of carbon emissions rather than the U.S.monetary policies.As such,monetary authorities’commitment to maintaining stable exchange rates comes together with monetary policies aiming at pursuing low-carbon growth.The new system potentially poses a plausible solution to the classical Mundellian Trilemma because the objectives of maintaining fixed exchange rate and implementing monetary policy become one.Although several hurdles are constraining the launch of carbon currency immediately,the carbon standard poses a feasible international monetary system as the world-wide campaign to achieve carbon neutrality progresses.