Renaud Kiesgen de Richter

Institut Charles Gerhardt Montpellier | ICGM · UMR5253 CNRS-UM2
ENSCM-UM1

The urban heat island effect is a widespread phenomenon in major cities worldwide, exerting significant impacts on urban environments, human health, and energy consumption, thus attracting extensive research interest. The manifestation of the urban heat island effect varies across different urban forms. This study employs a three-dimensional porous...

The construction industry is responsible for a significant amount of global energy consumption and CO2 emissions. To address this issue, phase change material (PCM) is commonly used as an effective heat storage material in building construction. It improves the thermal comfort of building occupants and reduces energy consumption. This paper provide...

Methane is the second largest contributor to global surface air temperature rise. Reducing atmospheric methane will mitigate climate change and improve air quality. Since the main sink of methane is the hydroxyl radical (OH) in the atmosphere, increasing OH concentration will accelerate the methane oxidation process and reduce methane concentration...

The solar chimney power plant (SCPP) provides the approach to achieving carbon neutrality goals. The power generation of the system decreases drastically due to the ambient crosswinds (ACWs). In this paper, three wind resistant structures, including blockage wall, radial partition wall (RPW), and porous wall are adopted to weaken the effects of the...

The downdraft energy tower is proposed in research as a new technology for green electricity in recent years. In this work, it is analyzed as an emerging greenhouse gas removal technology against climate change that provides multiple co‐benefits for the environment, in addition to green electricity. Compared to other negative emission technologies,...

The techniques for the removal of methane from the atmosphere are highly challenging due to its stable chemical properties, dispersed sources, and low concentrations. This paper proposes a practical small-scale solar chimney (SC) in buildings with photocatalytic reactors (PCRs) for atmospheric methane removal. Two comprehensive numerical models on...

The increase of 1.09 °C in global temperature resulted in significant catastrophes because of the extreme climate. The climate change rate can be slowed down by reducing the levels of CH4 and CO2 in the atmosphere. The solar chimney power plant integrated with a honeycomb photocatalytic reactor (SCPP-HPCR) uses the photocatalytic technology to remo...

Pollutant distribution remains poorly understood when traffic tidal flows (TTFs) happen. By conducting computational fluid dynamic (CFD) simulations, the research efforts first focus on how different-side traffic-produced flow and turbulence (TPFT) affect in-canyon airflow and corresponding pollutant dispersion. Second, the composite effects of non...

A simplified solar updraft device adapted from the Trombe wall concept was built to process large‐scale airflow using only solar energy. The performances were systematically studied using experimental measurements and numerical models, with the focus of investigating whether this device can generate enough airflow under low solar intensities, and d...

According to the latest report from the intergovernmental panel on climate change (IPCC), currently, global warming due to methane (CH4) alone is about 0.5°C while due to carbon dioxide (CO2) alone is about 0.75°C. As CH4 emissions will continue growing, in order to limit warming to 1.5˚C, some of the most effective strategies are rapidly reducing...

Methane's global warming potential (GWP) is much larger than carbon dioxide and contributes significantly to global warming. Solar chimney power plant (SCPP) integrated with photocatalytic reactors can capture and remove atmospheric methane, and generate electrical power without fossil energy consumption simultaneously. In this paper, the performan...

Methane (CH4) is a potent greenhouse gas. Solar‐driven gas phase advanced oxidation processes can fill the technology gap for CH4 removal. In their Review (DOI: 10.1002/chem.202201984). Li, Mu, et al. analyse the challenges and prospects and propose some ideas for the research in this area.

Various authors have highlighted the possible removal of methane from the atmosphere via oxidation by broad releases of iron salt aerosols in order to serve climate protection goals. This technique is known as enhanced atmospheric methane oxidation (EAMO). This study proposes and employs a modeling approach for the potential environmental impacts a...

Methane (CH4) is a potent greenhouse gas and the second highest contributor to global warming. CH4 emissions are still growing at an alarmingly high pace. To limit global warming to 1.5 °C, one of the most effective strategies is to reduce rapidly the CH4 emissions by developing large‐scale methane removal methods. The purpose of this perspective p...

The greenhouse effect is exacerbated as greenhouse gas concentrations rise. Capturing and degrading methane in the atmosphere can effectively slow the trend of global temperature rise. The solar chimney power plant integrated with photocatalytic reactor (SCPP‐PCR) is a promising concept for both clean electricity generation and large‐scale atmosphe...

The noise reduction effect of noise barriers has been extensively studied, but the effect on pollutant dispersion remains unclear. A computational fluid dynamics (CFD) simulation is conducted to investigate the effects of different heights, lengths, and types of noise barriers and different wind speeds on pollutant dispersion in street canyons with...

Methane's contribution to radiative forcing is second only to that of CO2. Though previously neglected, methane is now gaining increasing public attention as a GHG. At the recent COP26 in Glasgow, 105 countries signed “the methane pledge” committing to a 30% reduction in emissions from oil and gas by 2030 compared to 2020 levels. Removal methods ar...

Atmospheric methane removal (e.g. in situ methane oxidation to carbon dioxide) may be needed to offset continued methane release and limit the global warming contribution of this potent greenhouse gas. Because mitigating most anthropogenic emissions of methane is uncertain this century, and sudden methane releases from the Arctic or elsewhere canno...

Due to the alarming speed of global warming, greenhouse gas removal from atmosphere will be absolutely necessary in the coming decades. Methane is the second most harmful greenhouse gas in the atmosphere. There is an emerging technology proposed to incorporating photocatalysis with solar updraft Towers (SUT) to remove methane from the air at a plan...

Methane (CH4) is the second largest contributor to global warming among all greenhouses gases. A solar chimney power plant integrated with a photocatalytic reactor (SCPP-PCR) is a promising large-scale method for removing CH4 from the atmosphere. This study used computational fluid dynamics (CFD) to investigate the performance and factors influenci...

The urban heat island (UHI) effect resulted from urbanization as well as industrialization has become a major environmental problem. UHI effect aggravates global warming and endangers human health. Thus, mitigating the UHI effect has become a primary task to address these challenges. This paper verifies the feasibility of a three-dimensional turbul...

During their rapid economic development and industrialization, megacities in the developing nations with high populations (especially in the east and south Asia) are plagued by severe air pollution problems (e.g., heavy haze), which impose a threat not only to public health but also to the sustainable development of society and the economy. To reli...

Outdoor air pollution is a significant global issue because it poses a major long-term health risk. A growing number of studies are conducted to develop local mitigation strategies for improving air quality. This review paper critically evaluates the available literature to provide a better understanding of potential local mitigation strategies and...

Fulfilling the Paris Climate Agreement requires reducing rapidly the new emissions of greenhouse gases (GHGs) to reach net zero by 2050. As some anthropogenic emissions cannot be zero, to compensate them it will be necessary to remove GHGs from the atmosphere. Among possible methods, the Iron Salt Aerosol (ISA) offers new possibilities, including r...

Cities are facing significant challenges due to low outdoor air quality. Hence, a growing number of studies have been conducted to develop strategies for improving air quality. This paper provides a comprehensive and systematic review of the mechanisms and effects of various mechanical measures and urban morphology on pollutant dispersion in an urb...

The freeze-melting process can be a viable method for the purposes of desalination because of its low energy consumption, ignorable corrosion issues, and without huge pressure or membrane replacement work. Large contact area for heat and mass transfer per unit mass of water between the water and air and low heat resistance results in higher energy...

The microenvironment, which involves pollutant dispersion of the urban street canyon, is critical to the health of pedestrians and residents. The objectives of this work are twofold: (i) to effectively assess the pollutant dispersion process based on a theory and (ii) to adopt an appropriate stratigy, i.e., wind catcher, to alleviate the pollution...

Moving vehicles are the primary emission source of road pollution and the vehicle-induced turbulence (VIT) affecting the flow field in the street canyon. This paper used the dynamic mesh updating method to simulate the air pollution under the real situation of vehicle movement and exhaust emission in the street canyon. The dispersion characteristic...

The turbulence induced by moving vehicles influences the flow field and pollutant dispersion in street canyons. In this paper, an ambient crosswind-vehicle movement mathematical model was established to analyze the turbulent kinetic energy(TKE) that is induced by a single vehicle for different wind directions; a new method--dynamic mesh updating me...

Atmospheric methane concentration is currently increasing, due to anthropogenic fugitive emissions from fossil fuels, livestock, wetlands, rice paddies, … Accelerating permafrost thawing might release large amounts of methane and CO2. Submarine reserves of methane-hydrates could release large quantities of methane in a short time. The global warmin...

We made a presentation made on 11th Sept. 2019 at Westminster in London UK, to the Institution of Mechanical Engineers. https://events.imeche.org/ViewEvent?code=TDB6974 Overview With the UK Parliament joining many other national governments and international institutions in declaring a climate emergency, new impetus has been given to radical app...

Global Warming will probably modify air circulation patterns and increase the severity of droughts, heat waves, heavy precipitation, and floods across the world. A device called ‘aerological accelerator’ (AeAc) is proposed in this paper to harvest water from the air using a very high tower where the warm and humid air enters from the bottom and ris...

Moving vehicles exert a considerable influence on air flow and turbulence within urban street canyons, which is an important consideration for the pollutant dispersion and thus, local air quality management. In order to evaluate vehicle-induced turbulence and its contribution to pollutant dispersion, this study proposes a computational fluid dynami...

The book: Managing Global Warming: An Interface of Technology and Human Issues discusses the causes of global warming, the options available to solve global warming problems, and how each option can be realistically implemented. It is the first book based on scientific content that presents an overall reference on both global warming and its soluti...

Iron salt aerosol (ISA) makes Cloud Condensation Nuclei (CCN) that increase rain while reducing light and heat. Reacting with sunlight, ISA depletes methane and other potent greenhouse gasses, and then falls with the rain as a safe, widely dispersed natural fertilizer, removing CO2 by plankton photosynthesis at the base of the food chain. DOI: 10.1...

To limit global warming to well below 2ºC, most of the IPCC emission scenarios require overshooting the carbon budget at first and then remove the excess carbon dioxide and other GHGs with large negative emissions, typically on the order of 400‑800 Gt eqCO2 up to 2100. At the same time Negative Emissions of GHGs appear to be indispensable to meet c...

To limit global warming to well below 2ºC, most of the IPCC emission scenarios require overshooting the carbon budget at first and then remove the excess carbon dioxide and other GHGs with large negative emissions, typically on the order of 400‑800 Gt eqCO2 up to 2100. At the same time Negative Emissions of GHGs appear to be indispensable to meet c...

To limit global warming, governments and industries are engaged in reducing emissions of CO2. There is increasing evidence, however, that it may be necessary to go a step further by removing CO2 already emitted. For the purpose of Carbon Dioxide Removal (CDR), a number of Negative Emissions Technologies (NET) have been proposed. These generally mak...

A three-dimensional geometrical model was established based on a section of street canyons in the 2nd Ring Road of Wuhan, China, and a mathematical model describing the fluid flow and pollutant dispersion characteristics in the street canyon was developed. The effect of traffic tidal flow was investigated based on the measurement results of the pas...

In this paper, the desalination performance of a plant variant with the same size as the Manzanares pilot model was numerically investigated. A three-dimensional compressible flow and heat transfer model has been developed, describing the air cooling process along the chimney and the associated condensation. In this plant variant, instead of instal...

Large-scale atmospheric removal of greenhouse gases (GHGs) including methane, nitrous oxide and ozone-depleting halocarbons could reduce global warming more quickly than atmospheric removal of CO2. Photocatalysis of methane oxidizes it to CO2, effectively reducing its global warming potential (GWP) by at least 90%. Nitrous oxide can be reduced to n...

The acceleration of urbanization process, which triggered a series of environmental issues, has become increasingly prominent. Air pollution, especially atmospheric fine particulate matter (PM2.5), is one of the most severe pollutions affecting the human health and living standard. In this article, a novel solar chimney with an inverted U-type cool...

A solar chimney power plant (SCPP) is not only a solar thermal application system to achieve output power, but also a device extracting freshwater from the humid air. In this article, we proposed a SCPP with collector being replaced by black tubes around the chimney to warm water and air. The overall performance of SCPP was analyzed by using a one-...

The solar updraft power plant system (SUPPS) is a low -temperature solar thermal system which utilizes both the buoyancy effect of hot air generated inside a greenhouse by solar radiation and the chimney effect to generate electricity without producing either greenhouse gases or hazardous waste. In this work, a brief review is presented concerning...

Power stations, ships and air traffic are among the most potent greenhouse gas emitters and are primarily responsible for global warming. Iron salt aerosols (ISAs), composed partly of iron and chloride, exert a cooling effect on climate in several ways. This article aims firstly to examine all direct and indirect natural climate cooling mechanisms...

Power stations, ship, and air traffic are among the most potent greenhouse gas emitters and primarily responsible for global warming. Iron salt aerosols (ISA) exert a cooling effect on climate in several ways. This article aims firstly to examine all direct and indirect natural climate cooling mechanisms driven by tropospheric aerosol particles com...

Even if humans stop discharging CO2 into the atmosphere, the average global temperature will still increase during this century. A lot of research has been devoted to prevent and reduce the amount of carbon dioxide (CO2) emissions in the atmosphere, in order to mitigate the effects of climate change. Carbon capture and sequestration (CCS) is one of...

To investigate the impact of a strong ambient crosswind on the system output power through the collector inlet and chimney outlet, numerical analysis on the performances of a solar updraft power plant systems (SUPPS) identical to the prototype in Manzanares, Spain which is exposed to the external crosswind with different velocities was carried out...

In order to mitigate the effects of climate change, a lot of research has been devoted to reduce carbon dioxide (CO2) emissions, develop capture and storage technologies (CCS), as well as direct carbon dioxide removal (CDR) from the atmosphere. The 2014 "Summary for Policymakers" of the Intergovernmental Panel on Climate Change 5th report (working...

The current growth of desalination capacity is contributing to energy usage and carbon dioxide emissions. Desalination plants discharge reject brine containing magnesium chloride. Conversion of magnesium chloride into magnesium carbonate or biocarbonate is a possible method to absorb carbon dioxide from the atmosphere, the oceans, or from point sou...

Solar energy can meet air conditioning summer energy demand. But in many countries, actual winter peak in demand is after sunset around 6 pm. Experience with wind turbines has shown that in many occasions at the peak demand wind power is down close to zero and presents serious output power fluctuations. Due to their intermittent nature, and as fund...

Coal-fired power stations emit both CO 2 and sulphur dioxide into the troposphere. But if SO 2 is removed, global warming will get worse as SO 2 delivered to the atmosphere forms aerosols with strong negative radiative forcing, thus offsetting the positive radiative forcing from CO 2 emissions. However, because the SO 2 is relatively short-lived (~...

Existing research indicated that the ambient crosswind (ACW) has very complex influences on the SUPPS both through the chimney outlet and collector inlet as demonstrated by numerical analysis from the Spanish prototype. But what influence exert ACW through chimney outlet and collector inlet independently on the overall performance of SUPPS is still...

« La géo‐ingénierie de l’environnement correspond à l’ensemble des techniques et pratiques mises en oeuvre ou projetées dans une visée corrective à grande échelle d’effets de la pression anthropique sur l’environnement. Il importe de bien distinguer la géo‐ingénierie qui met en jeu des mécanismes ayant un impact global sur le système planétaire ter...

Engagé en septembre 2012, l’ARP REAGIR est consacré à la géo-ingénierie environnementale. La réflexion a été menée par des chercheurs, en sciences sociales et naturelles, et des experts des secteurs publics et privés. Les solutions imaginées de géo-ingénierie ont été analysées à différentes échelles spatio-temporelles avec une vision large et aussi...

Geoengineering schemes propose solar radiation management technologies that modify terrestrial albedo or reflect incoming shortwave solar radiation back to space. Instead we propose "earth radiation management" and to enhance outgoing longwave radiation http://www.sciencedirect.com/science/article/pii/S1364032113008460 to fight global warming. In t...

The best way to reduce global warming is, without any doubt, cutting down our anthropogenic emissions of greenhouse gases. But the world economy is addict to energy, which is mainly produced by fossil carbon fuels. As economic growth and increasing world population require more and more energy, we cannot stop using fossil fuels quickly, nor in a sh...

Export Date: 4 January 2015

Ambient crosswind has complicated influence on the performance of the solar updraft power plant system (SUPPS) both via the collector inlet and via the chimney outlet. To overcome the negative impact of strong ambient crosswind on the performance of a 50 kW SUPPS model with the same dimensions as the prototype in Manzanares, Spain through the colle...

SUMMARY Severe fluctuation of the output power is a common problem in the generating systems of various renewable energies. The concept of output power fluctuation factor of renewable energy power generating systems was put forward in this paper. Aiming to decrease the fluctuation factor of output power in solar chimney power generating systems (SC...

SUMMARYA large number of researchers have paid great attention to solar chimney (SC) power generating technology, but only a few have studied the chimney configuration. Taking a 10 MW SC system as an example, the physical and mathematical models illustrating the fluid flow, heat transfer and output power features of the system are established. Base...

Over the last decades, fighting global warming has become the most important challenge humanity has to face. Therefore technologies of carbon dioxide capture, sequestration and recycling are equally important in order to tackle the global climate change stakes. Among recycling technologies, photocatalytic processes reducing CO2 with H2O back to fue...

Until today, the biggest solar updraft tower power plant ever built and tested was the 50 kW Spain plant in Manzanares. Since then no real plant has been built, whilst many grand plans have been drawn and given up. Solar Wind Power (SWP) is an energy form in search of its destiny: it is time to find a real market for SWP. This market is currently f...

Over the last decades, fighting global warming has become the most important challenge humanity has to face. Therefore technologies of carbon dioxide capture, sequestration and recycling are equally important in order to tackle the global climate change stakes. Among recycling technologies, photocatalytic processes reducing CO 2 with H 2 O back to...

The solar updraft power plant system (SUPPS) is a novel kind of solar thermal application, which uses the fluid buoyancy of the chimney effect to achieve output power. To investigate the impact of a strong ambient crosswind on the system output power through the collector inlet and chimney outlet, numerical analysis on the performances of a SUPPS i...

At the laboratory scale, photocatalysis is a promising method to convert many air pollutants such as nitrogen oxides and volatile organic compounds, to safer products for human health but also environmentally more acceptable, such as nitrate and carbon dioxide. Indoor and industrial applications of photocatalysis to remove local air pollutants fro...

In order to decrease their time return on investment, all the solar chimney power projects (SCPP) describe alternative income sources like: certificates for carbon dioxide (CO2) compensation, farming under the greenhouse, tourism, R&D centres, telecommunications... Other synergies could arise from photo-catalysed oxidation of atmospheric methane (C...

Sodium tungstate has been found to correct hyperglycemia in insulin- and noninsulin-dependent models of diabetes when administered in drinking fluid with a low degree of toxicity; thus, it provides a potential treatment for diabetes. In the present report, pharmacokinetic studies with sodium tungstate were carried out in the Sprague-Dawley rat and...

This paper describes an inductively coupled plasma emission spectrometric method for the analysis of tungsten in dog and rat plasma. Calibration curves were obtained in the range 134–1300 ng/ml. The relative standard deviation ranged from 0.4 to 17%, and accuracy was between 89 and 105%. Dilution has no influence on the performance of the method wh...

A reverse phase liquid chromatographic method has been developed to assay benzathine benzylpenicillin and also to estimate potential impurities. This method has been subjected to an interlaboratory trial to assess its reproduc-ibility for the assay of content and its suitability to control its potential impurities. The reproducibility relative stan...

An inter-laboratory trial has been conducted to assess the suitability for pharmacopoeial use of reverse liquid chromatographic methods for the assays of procaine and benzylpenicillin in procaine benzylpenicillin and for a test for related substances. The assay results of three samples analysed by eight laboratories have been statistically evaluate...

Les progrès réalisés dans les domaines des phases stationnaires, de l'instrumentation, de la quantification et des possibilités de détection, ont conduit à une renaissance de la chromatographie planaire. La chromatographie en couche mince ne constitue pas uniquement une alternative économique ; il s'agit d'une méthode pratique, rapide et fiable qui...

Progress in the areas of stationary phases, instrumentation, quantification and detection possibilities, led to a renaissance of planar chromatography. The thin layer chromatography is not only an economical alternative; TLC is practical, rapid and reliable, and does not require complex sample preparation. A major advantage of this technique is to...

Progress in the fields of stationary phases, instrumentation, quantitation and detection possibilities has led to renewed interest in planar chromatography. Thin layer chromatography is not only a viable economic alternative, but is a practical, rapid and reliable method that does not require complex sample preparation. One of the major advantages...

Oxidation of (+)-pinene, followed by NaBH4 reduction, produces (+)-myrtenol (II) which is converted into (+)-myrtenyl bromide (III) by reaction with bromine in the presence of triphenylphosphine.

Both (+)- and (-)-myrtenyldithiane derivatives were independently prepared from commercially available chiral precursors and were easily, and in one step, converted by means of borane complexes into solid and stable chiral monoalkylboranes: (+)- and (-)-[2-(1,3-dithianyl)]myrtanylborane (MDBH2). These new chiral reagents, when tested on representat...