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1.
Frontiers in Climate ; 4, 2022.
Article in English | Scopus | ID: covidwho-1987477

ABSTRACT

One of the most important challenges our global civilization faces in the coming years is to achieve the Paris Agreement's goals of preventing the planet's temperature from exceeding the pre-industrial values of 2°C and limiting it, at most, to 1.5°C. Awareness of this problem has led to the creation of many national and international organizations in recent decades, with many thematic conferences being held and new policies to reduce greenhouse gas emissions—so far without attaining the necessary success. Among the political measures taken in recent years is the climate emergency declaration issued by many government institutions, highlighting the serious and urgent problem of climate change and the imperative need to find a solution. The COVID-19 pandemic, has led to reductions in CO2 emissions due to the substantial decreases in economic activity incurred by several countries imposing non-pharmaceutical interventions. Thus, the current practice of declaring a climate emergency must be fortified by making it a legal tool in order to reduce CO2 emissions and reach the objectives set by the Paris Agreement. Yet, what should this climate emergency declaration look like? In considering these current COVID-19-induced reductions in CO2 emissions, we hereby propose a political plan for stopping emissions to try to achieve the objectives of the Paris Agreement and at least some of the UN's 2030 Sustainable Development Goals. The article also proposes how to define the global climate alarm declaration to serve as an international legal tool for reducing CO2 and transitioning to a world free of these massive emissions. By analyzing the reduction of the emissions in different scenarios based on the COVID-19 pandemic, the article shows that the needed reduction of emissions proposed by the EU in 2030 cannot be reached in any of the scenarios limiting the CO2 emissions. Copyright © 2022 Mazon, Pino and Vinyoles.

2.
Energies ; 15(7):2430, 2022.
Article in English | ProQuest Central | ID: covidwho-1785583

ABSTRACT

Among the G20 countries, China is the only country to experience an increase in electricity generation from coal-fired thermal power plants from 2019 to 2020. This study aims to develop an analytical framework combining metafrontier data envelopment analysis with the logarithmic mean Divisia index for a detailed decomposition analysis of ‘mass-based’ energy-related CO2 reduction potential through efficiency improvements in coal-fired thermal power plants in China. The results show that inefficiency in power generation can be largely attributed to differences in the location of power plants and the production scale. Moreover, the impact of regional heterogeneity on the changes in power generation efficiency is more notable for the small–medium power plants in the northeast region than the large power plants in the western region in China. However, when focusing on the mass-based CO2 reduction potential associated with the regional heterogeneity, its positive effects in the western region for the large power plants are 6.2 times larger than that in the northeast region for the small–medium power plants. These results imply that an analysis that focuses only on the efficiency score would ignore the production scale of coal-fired thermal power plants and thus would fail to properly evaluate the environmental impacts associated with efficiency changes.

3.
Int J Environ Res Public Health ; 19(5)2022 Mar 03.
Article in English | MEDLINE | ID: covidwho-1732012

ABSTRACT

Due to the current COVID-19 pandemic, guaranteeing thermal comfort and low CO2 levels in classrooms through efficient ventilation has become vitally important. This study presents three-dimensional simulations based on computational fluid dynamics of airflow inside an air-conditioned classroom located in Veracruz, Mexico. The analysis included various positions of an air extractor, Reynolds numbers up to 3.5 × 104, four different concentrations of pollutant sources, and three different times of the day. The simulations produced velocity, air temperature, and CO2 concentrations fields, and we calculated average air temperatures, average CO2 concentrations, and overall ventilation effectiveness. Our results revealed an optimal extractor position and Reynolds number conducive to thermal comfort and low CO2 levels due to an adequate ventilation configuration. At high pollutant concentrations, it is necessary to reduce the number of students in the classroom to achieve safe CO2 levels.


Subject(s)
Air Pollution, Indoor , COVID-19 , Air Pollution, Indoor/analysis , Air Pollution, Indoor/prevention & control , COVID-19/epidemiology , Carbon Dioxide/analysis , Humans , Pandemics , SARS-CoV-2
4.
Catal Today ; 2020 Oct 17.
Article in English | MEDLINE | ID: covidwho-866477

ABSTRACT

A unified treatment of the renewable portfolio standards is given concerning direct methanol fuel. The current mechanism of electrocatalysis of methanol oxidation on platinum and non-platinum-containing alloys is summarized for the systematic improvement of the rate of electro-oxidation of methanol are discussed. Policy realignment under the five-year plan is discussed in length to demonstrate how policy, markets, and engineering designs contribute towards the development of model direct methanol fuel cells operational enhancement, and factors that affect critical performance parameters for commercial exploitation are summarized for catalytic formulations and cell design within the context of why this investment in technology, education, and finances is required within the global context of sustainable energy and energy independence as exposed by thirteenth the five-year plan. The prolog focuses on the way, whereas the section on methanol fuel cells on the how and the post log on what is expected post-COVID-19 era in science and technology as China pivots to a post-fossil fuel economy. China's industrial growth has been through internal market reforms and supplies side economics from the Chinese markets for fossil fuels except for petroleum. The latest renewable portfolio standards adopted have common elements as adopted from North American and the United Kingdom in terms of adaptation of obligation in terms of renewable portfolio standards as well as a realization that the necessity for renewables standards for the thirteen five year plan (from 2016 to 2020) need to less rigorously implemented due to performance targets that were met during the eleventh (06-10) and twelfth five-year plans (11-15) in terms of utilization of small coal-ire power plants, development of newer standards, led to an improvement of energy efficiency of 15 %, reduction of SOx/NOx by an average of 90 % and PM2.5 by 96 % over the last two five-year plans. The current phase of the plan has a focus on energy generation from coal and a slowing down of renewables or Renewable energy curtailment of approximately 400 T Wh renewables including 300 T Wh of non-hydro power, principally from Guangdong, and Jiangsu for transfer of hydropower and Zhejiang, Tianjin, Henan for non-hydro power transfer with Beijing and Shanghai playing important roles in renewables energy curtailment and realignment using an integrated approach to optimize each provinces energy portfolio. The realignment of the renewable energy portfolio indicates that the newly installed capacity in Sichuan, Yunnan, Inner Mongolia, and Zhejiang will account for less than 20 % of the current renewable energy portfolio but with the NOx SOx and PM2.5 savings already accrued. The catalytic reduction of carbon dioxide to methanol (70 / 110 million metric tons from all sources in 2019 for China/world) is one technological approach to reduce global carbon dioxide emissions and suggests that catalytic methanol synthesis by CO2 hydrogenation may be a plausible approach, even if it is more expensive economically than methanol synthesis by the syngas approach. This is because the CO2 emissions of the synthesis are lower than other synthesis methodologies. The Chinese government has placed a premium on cleaner air and water and may view such an approach as solving the dual issues of fuel substitution and reduction of CO2. Thus, the coupling of hydrogen generation from sustainable energies sources (Solar 175 / 509 GW) or wind (211/591.5 GW in 2019) may be an attractive approach, as this requires slightly less water than coal gasification. Due to the thermodynamic requirement of lower operating pressure and higher operating pressure, currently, there is no single operational approach, although some practice approaches (220 °C at 48 atm using copper) and zinc oxide/alumina are suggested for optimal performance.

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