News Article | May 19, 2017
It may seem counterintuitive but a recent study has shown that, especially during heat waves, trees in a city can increase the rates of ozone formation (Credit: sata.creative.gmail.com/Depositphotos ) A recent study by a Berlin-based team of scientists has revealed that during heat waves, trees in a city can actually contribute to higher levels of air pollution. As many cities around the world become greener with plant-clad towers, vertical gardens and tree-filled urban developments, the study highlights the need to take into account the location and types of greenery being planted. We know that there are significant benefits to planting trees in cities, from their ability to store carbon to the way they keep urban areas cool, but we also know that trees can release more than just oxygen into the atmosphere. Trees and other plants are known to release volatile organic compounds (VOCs). In the presence of sunlight, VOCs and nitrogen dioxide (NOx) react to form ozone, a key pollutant that when produced at ground level causes smog and respiratory problems in humans. Galina Churkina and her team at the Institute for Advanced Sustainability Studies and Humboldt University, used computer models to study air pollutant concentrations in an area of Berlin. They looked at the data from a heat wave in summer 2006 and compared it to a more typical seasonal stretch in the summer of 2014. Knowing that plants release higher levels of VOCs when it is hot, the team was looking at whether those areas of greenery in the city showed higher levels of ozone formation during warmer periods. The team concluded that ozone levels did indeed spike in areas of urban greenery during the heat waves. Their simulations estimated the VOCs contributed to anywhere from six to 20 percent of the ozone formation during the heat wave, with spikes of up to 60 percent at some points. The study highlights the hidden complexities involved in managing our urban air environments. Simply planting more trees can sometimes result in increases of certain types of air pollution, despite the other benefits of greener urban spaces. The solution of course, is not to stop planting trees but rather make sure several factors are considered as we further develop our city spaces. Churkina and her team have identified that certain species of trees emit greatly reduced volumes of VOCs – birch trees, for example, release over 15 times less VOCs than black gums. Where to locate high-densities of trees needs to be considered as well, such as avoiding planting a high-VOC emitting species such as black gums near high-traffic streets. But the biggest solution to this counterintuitive conundrum is to simply work on reducing NOx emissions, which should decrease as the numbers of electric vehicles on the roads increase. The broader benefits of bringing in greenery to cities is evident, so a goal of reducing emissions from vehicular traffic should be paramount, and also conducted in tandem with any urban tree-planting campaign so as to maximize the environmental benefits rather than creating ozone-producing smog traps. The team's research was published in the journal Environmental Science and Technology.
News Article | November 19, 2015
« ROEV Association forms to promote public EV charging interoperability | Main | Renault-Nissan Alliance installing 90 new charge spots for COP21 summit in Paris » Researchers of the Institute for Advanced Sustainability Studies (IASS) in Potsdam and the Karlsruhe Institute of Technology (KIT) have achieved the proof-of-principle for a innovative technique to extract hydrogen (H ) from methane (CH ) without the formation of CO as a byproduct. At this stage, cost estimates are uncertain, since methane cracking is not yet a fully mature technology. However, preliminary calculations show that it could achieve costs of €1.9 to €3.3 per kilogram of hydrogen at German natural gas prices—without taking the market value of the solid black carbon byproduct of the process into consideration. Most of the world’s hydrogen production is currently based on conventional technologies such as steam methane forming (SMR), which also uses natural gas as feedstock but releases significant amounts of carbon dioxide in the process. CO emissions from the ammonia industry alone amount to approximately 200 million tons per year—by comparison, Germany generates around 800 million tons of carbon dioxide per year. By contrast, methane cracking—the separation of methane’s hydrogen and carbon molecular components—occurs at high temperatures (750°C and above) but does not release any harmful emissions. The main by-product of methane cracking—solid black carbon—is also an increasingly important industrial commodity. It is already widely employed in the production of steel, carbon fibres and many carbon-based structural materials. The black carbon derived from the novel cracking process is of high quality and is a particularly pure powder. Its value as a marketable product therefore enhances the economic viability of methane cracking. Alternatively, black carbon can be stored away, using procedures that are much simpler, safer and cheaper than the storing of carbon dioxide. Methane cracking itself is not an entirely new idea: in the last two decades, many experiments in different institutions have been carried out that have proven its technical feasibility. But these past attempts were limited by issues such as carbon clogging and low conversion rates. The IASS and KIT team built an experimental reactor that could demonstrate the potential of methane cracking and overcome previous obstacles. The starting point is a novel reactor design, as proposed by Nobel Laureate and former IASS Scientific Director Professor Carlo Rubbia and that is based on liquid metal technology. Fine methane bubbles are injected at the bottom of a column filled with molten tin. The cracking reaction happens when these bubbles rise to the surface of the liquid metal. Carbon separates on the surface of the bubbles and is deposited as a powder at the top end of the reactor when they disintegrate. This idea was put to the test during a series of experimental campaigns that ran from late 2012 to the spring of 2015 in KIT’s KALLA (KArlsruhe Liquid Metal LAboratory). Researchers were able to evaluate different parameters and options, such as temperature, construction materials and residence time. The final design is a 1.2-meter-high device made of a combination of quartz and stainless steel, which uses both pure tin and a packed bed structure consisting of pieces of quartz. The innovative reactor is resistant to corrosion, and clogging is avoided because the microgranular carbon powder produced can be easily separated. The reactor thus satisfies the technical preconditions that would be needed for the continuous operation of an industrial-scale reactor. While these remain laboratory-scale experiments, researchers can extrapolate from them to gain insights into how methane cracking could be integrated into the energy system and, more specifically, what its contribution to sustainability could be. To this end, the IASS is collaborating with RWTH Aachen University to conduct a life cycle assessment (LCA) of a hypothetical commercial methane cracking device based on a scaling-up of our prototype. The LCA assumes that some of the produced hydrogen is used to generate the required process heat. The compared hydrogen production technologies were steam methane reforming (SMR) and water electrolysis coupled with renewable electricity. With respect to emissions of carbon dioxide equivalent per unit of hydrogen, the LCA showed that methane cracking is comparable to water electrolysis and more than 50% cleaner than SMR. In the next phase of the process, the IASS and KIT will focus on optimising some aspects of the reactor design, such as the carbon removal process, and progressively scaling it up to accommodate higher flow rates.
News Article | December 11, 2015
A team of researchers from the Universidad Politécnica de Madrid (UPM), in collaboration with the Nobel Laureate Carlos Rubbia from the Institute for Advanced Sustainability Studies (IASS, Potsdam, Germany) and the King Abdulaziz University of Arabia Saudi, have developed a technology based on the use of carbon dioxide to improve the energy production in solar fields. The usage of this fluid on solar energy has been verified by the research group of UPM at the Almeria Solar Platform (PSA), achieving excellent results: fluid and inexpensive solar fields that are friendly to the environment. Agriculture has always been a benchmark for production systems in which huge areas are required to obtain economic benefits and trying to reduce harvesting costs. This principle can be applied to the use of solar energy on solar fields for renewable energy production where there are two major competitors: photovoltaic energy and thermal energy. The first competitor cannot currently store large amounts of the energy produced with optimal performance. However, thermal energy allows us to storage energy improving the management of renewable energy, similar to a dam that stores water for a hydroelectric plant. In the case of solar thermal energy, there are four commercialized technologies with varying costs and energy conversion efficiencies: parabolic trough, power tower, solar dish and linear Fresnel system. The first two types have been developing since the 80s but the other two technologies have been less developed. In fact, the analogous to the three-bladed wind turbines has not been found yet. Researchers have carried out a study that adopts an innovative prospect for making design decisions: thermal coherence that prevents excessive temperatures or unnecessary material usage. Observing other fields of energy engineering such as nuclear powers plant is required, since numerous plants work with moderate temperatures (300ºC). Therefore, the solar industry trend of reaching higher temperatures can be unsuitable. Besides, the high production cost can slow down the technological development of the assumed design philosophies. Thus, the disruptive innovation proposed in this study has more potential. The development of these ideas leads to an improved concept of Fresnel by using carbon dioxide as a fluid working that can be used in severe thermal applications such as the cooling of high-temperature nuclear reactors. In addition, the usage CO2 in solar energy can work to confine this fluid and, at the same time, prevent emissions by replacing other thermoelectric plants that use fossil fuels. The technology, developed by UPM researchers, is currently being exploited through the Futuro Solar project by signing an agreement between UPM and OHL Industrial. The Futuro Solar project was submitted in the 2nd call for Research and Development Projects co-financed by the European Economic Area Financial Mechanism (EEA-Grants). This technology is an advanced prototype of the learning curve regarding the current state of thermosolar technology. It is expected to start operating in spring 2016. Explore further: NREL report finds similar value in two concentrating solar power technologies More information: José M. Martinez-Val et al. A coherent integration of design choices for advancing in solar thermal power, Solar Energy (2015). DOI: 10.1016/j.solener.2015.06.016
News Article | November 19, 2015
The production of energy from natural gas without generating carbon dioxide emissions could fast become a reality, thanks to a novel technology developed by researchers of the Institute for Advanced Sustainability Studies (IASS) in Potsdam and the Karlsruhe Institute of Technology (KIT). In a joint project initiated by Nobel Laureate and former IASS Scientific Director Professor Carlo Rubbia, the two institutions have been researching an innovative technique to extract hydrogen from methane in a clean and efficient way. After two years of intensive experiments, the proof-of-principle has now been provided. With the experimental reactor running reliably and continuously, the future potential of this technology has become apparent.
Titirici M.-M.,Queen Mary, University of London |
White R.J.,Institute for Advanced Sustainability Studies |
Brun N.,Charles Gerhardt Institute |
Budarin V.L.,University of York |
And 4 more authors.
Chemical Society Reviews | Year: 2015
Carbon-based structures are the most versatile materials used in the modern field of renewable energy (i.e., in both generation and storage) and environmental science (e.g., purification/remediation). However, there is a need and indeed a desire to develop increasingly more sustainable variants of classical carbon materials (e.g., activated carbons, carbon nanotubes, carbon aerogels, etc.), particularly when the whole life cycle is considered (i.e., from precursor "cradle" to "green" manufacturing and the product end-of-life "grave"). In this regard, and perhaps mimicking in some respects the natural carbon cycles/production, utilization of natural, abundant and more renewable precursors, coupled with simpler, lower energy synthetic processes which can contribute in part to the reduction in greenhouse gas emissions or the use of toxic elements, can be considered as crucial parameters in the development of sustainable materials manufacturing. Therefore, the synthesis and application of sustainable carbon materials are receiving increasing levels of interest, particularly as application benefits in the context of future energy/chemical industry are becoming recognized. This review will introduce to the reader the most recent and important progress regarding the production of sustainable carbon materials, whilst also highlighting their application in important environmental and energy related fields. © The Royal Society of Chemistry 2015.
Bauch H.A.,Akademie der Wisssenschaften und der Literatur Mainz |
Kandiano E.S.,Helmholtz Zentrum fur Ozeanforschung |
Helmke J.P.,Institute for Advanced Sustainability Studies
Geophysical Research Letters | Year: 2012
Variations in the poleward-directed Atlantic heat transfer was investigated over the past 135ka with special emphasis on the last and present interglacial climate development (Eemian and Holocene). Both interglacials exhibited very similar climatic oscillations during each preceding glacial terminations (deglacial TI and TII). Like TI, also TII has pronounced cold-warm-cold changes akin to events such as H1, Blling/Allerd, and the Younger Dryas. But unlike TI, the cold events in TII were associated with intermittent southerly invasions of an Atlantic faunal component which underscores quite a different water mass evolution in the Nordic Seas. Within the Eemian interglaciation proper, peak warming intervals were antiphased between the Nordic Seas and North Atlantic. Moreover, inferred temperatures for the Nordic Seas were generally colder in the Eemian than in the Holocene, and vice versa for the North Atlantic. A reduced intensity of Atlantic Ocean heat transfer to the Arctic therefore characterized the Eemian, requiring a reassessment of the actual role of the ocean-atmosphere system behind interglacial, but also, glacial climate changes. © 2012 American Geophysical Union. All Rights Reserved.
News Article | December 20, 2016
If the Paris climate objectives are upheld, policymakers will soon be facing calls to set emission-reduction targets of much more than 100 percent, write Oliver Geden of the German Institute for International and Security Affairs (SWP) in Berlin and Stefan Schäfer of the Institute for Advanced Sustainability Studies (IASS) in Potsdam. But the debate about how to achieve “negative emissions” – and who will have to achieve them – has not even begun, they note. Global climate stabilisation targets, such as restricting global warming to 1.5 or 2 degrees Celsius (°C) above pre-industrial levels, can be translated into carbon budgets that show the total amount of emissions that would still be allowed for meeting the target. According to current calculations, the remaining emissions budget for the 2 °C target is about 800 gigatonnes (Gt) of carbon dioxide (CO ). However, for 1.5 °C, it is only about 200 Gt. Given that annual CO emissions currently stand at about 40 Gt, the world’s budget for 2 °C would be consumed by the mid-2030s, the budget for 1.5 °C as soon as the early 2020s. Since completely decarbonising the world economy within a time frame of only 5 to 20 years is unrealistic, climate models build on the concept of negative emissions. By using technologies to remove CO from the atmosphere, the original emissions budget could initially be overshot, with the resulting deficit then being recouped over the course of the 21st century. However, the looming budget deficit has now reached an alarming size. The Intergovernmental Panel on Climate Change’s (IPCC) climate models show that a total of 500 to 800 Gt in negative emissions would have to be generated by 2100 to limit global warming to 2 °C or 1.5 °C – in other words, up to twenty times the current annual CO emissions. In principle, all governments accept the scientific consensus set out by the IPCC in its 5th Assessment Report (2013-2014). The report points out that negative emissions cannot be avoided if ambitious climate targets are to be met. Currently, however, there is hardly any discussion on how to bring about negative emissions. This is particularly worrying because building the necessary capacities would have to start by 2030 at the latest. Since there is no political debate on negative emissions yet, potential conflicts of interests or public acceptance problems can only be guessed at. The possible social and ecological consequences of such a far-reaching use of technologies for CO removal have barely been examined. The biggest problem, however, is that almost all the technological options currently being favoured are still in the early stages of development, making their potential for successful deployment extremely uncertain. In its current climate-economic models, the IPCC almost exclusively refers to a technological option that combines planting fast-growing biomass, burning it in power stations to generate electricity, and capturing and storing the CO that is released in the process (bio-energy with carbon capture and storage – BECCS). During its growth phase, the biomass absorbs carbon dioxide from the atmosphere that is then captured during combustion and subsequently stored, for instance in geological formations. This process would be constantly repeated with new biomass, thus reducing the CO concentration in the atmosphere. So far, however, BECCS has barely been tested: there is only one single pilot facility in the US. Moreover, generating the amount of negative emissions that is assumed in climate-economic models would require an additional area for growing biomass that is equivalent to one-and-a-half to two times the surface area of India. Transporting the CO and storing it underground would also require enormous capacities. And yet the use of this technology is always already included in the calculations of climate researchers, environmental NGOs or policymakers when they insist that, based on the IPCC’s calculations, targets such as 2 °C or even 1.5 °C can still be met. Over half a dozen other technological options are also under discussion. They range from apparently unproblematic measures, such as afforestation, to fertilising or liming the oceans. On closer inspection, however, even a universally supported measure such as afforestation raises the question of whether it can really help to limit global warming. Especially for the boreal forests of the northern hemisphere, the darkening of the Earth’s surface that would result from an afforestation of large regions, and the attending warming effect, might more than cancel out the cooling effect that would result from binding CO in trees – thus achieving the very opposite of the intended outcome. By contrast, suggestions for afforestation of the Sahara or Australian outback simply seem unrealistic. Fertilising the oceans is based on the idea that algae growth in some maritime regions is limited by a lack of nutrients, especially iron. A targeted addition of iron could provoke algae growth, removing CO from the atmosphere: when the algae die and sink to the seabed, the CO stored in them would be permanently sequestered there. In 2009, the German-Indian iron-fertilisation experiment LOHAFEX attracted international attention to the idea of ocean iron fertilisation. From a climate-policy perspective, however, the results were disappointing. The algae growth primarily caused a local population of crustaceans to multiply. The amount of CO that was removed from the atmosphere was very small. Another possibility is liming the oceans. This involves adding calcium oxide powder (lime) to sea water to increase its pH value. Since water that is more alkaline absorbs more CO from the air, this method could extract carbon dioxide from the atmosphere. At the same time, it could ease the acidification of the oceans. However, the effectiveness of this option is once again questionable: producing calcium oxide powder is a CO -intensive process, and transporting it would also generate emissions. In climate research, at least, the potentials and risks of the individual technological options are now beginning to be explored. By contrast, the political implications of a negative emissions climate policy have not yet been elucidated. The United Nations’ (UN) policy to protect the climate has so far relied on allotting differentiated levels of responsibility to individual groups of states that will converge in the long term – at the very latest when all states have reduced their emissions to zero. Because of their historical responsibility and greater economic capability, the ‘old’ industrialised nations have to substantially reduce their emissions. Some of them, such as the northwestern member states of the EU, have claimed a pioneering status for themselves. Here, the so-called “zero line” – reducing emissions by 100 percent – has been the conceptual reference point. Some EU countries will reach the zero line earlier than others, but member states from Central and Eastern Europe will be obliged to follow suit. This is also true for large emerging economies like China and India. Convergence towards zero thus means a pioneering role for a limited period of time. The assumption that such a role will bring positive economic effects rests not least on the idea that the countries initially lagging behind will have to follow suit eventually, and will do so using technologies developed by the pioneers. However, should the limit of what is currently conceivable in emissions mitigation be removed, new conflicts about burden sharing would be inevitable. Possibilities for differentiating national climate targets would greatly increase, and the pioneers would have to play their part for much longer. For the year 2100, the IPCC considers net negative emissions of around 10 Gt to be feasible. This would correspond to a global emissions-reduction target of around 125 percent against the base year 1990. If this became a point of reference in the UN climate negotiations, key emitters like China or India, and most of the developing countries would likely argue that the industrialised nations organised in the Organisation for Economic Co-operation and Development (OECD) should continue to take on more far-reaching responsibilities. For instance, emerging economies and developing countries could demand that OECD countries invest more in carbon-dioxide removal whilst they themselves might not even reduce their own emissions to zero. If the EU agrees to a reduction target of, say, 150 percent, we should also expect to see conflicts within the Union: the latecomers from Central and Eastern Europe will be keen to maintain the EU’s internal distribution of responsibilities. Similar conflicts should also be expected between different economic sectors. If BECCS becomes the world’s preferred carbon-removal technology, the electricity sector would be the very first to be called upon to generate negative emissions. The sector is already the focal point of emissions- mitigation efforts and is likely to reach the zero line long before the transport or buildings sector. If climate policy pioneers like the EU and Germany do not want to prematurely abandon the temperature targets decided in Paris, they will have to start developing strategies for CO removal soon. As we have indicated, global emissions budgets for 1.5 °C and 2 °C will be consumed within five to 20 years. This means that the EU’s and Germany’s reduction corridor of 80 to 95 percent by 2050, can only be an adequate contribution to meeting global temperature targets if emissions in the second half of the century are pushed substantially below the zero line. To date, neither the EU nor Germany has declared itself ready to aim for long-term reduction targets of more than 100 percent. And even if they did, it remains unclear whether such a policy would be technologically and economically feasible, and if it would find sufficient socio-political support. In principle, a negative-emissions strategy can only be realised if climate, energy and research policy rapidly set the process in motion. Not only would it be necessary to invest substantially in research and development, but also to start a broad political and societal debate, and initiate regulatory considerations. In many respects, these considerations concern challenges that also had to be solved (or still remain to be solved) in deploying conventional emissions-mitigation technologies. For example, precise accounting rules for negative emissions need to be set out, undesired side effects need to be avoided, and specific incentive schemes for using CO removal technologies have to be created. It would seem logical to clarify these points as part of the existing regulatory framework, such as the EU emissions trading directive or the EU’s sustainability criteria for biomass. Politically, the most sensitive issues in any potential German strategy for negative emissions are linked to the fundamental decisions that have already been taken on Germany’s energy transition. Would Germany be prepared to rethink its energy transition planning for the electricity sector if BECCS emerged as the technology with the greatest potential at the global level? Would the federal government be willing to change course drastically on biomass and on carbon capture and storage, even at the expense of the decentralised expansion of wind and solar power? Or would it primarily encourage measures whose deployment would barely impact on the structure of the national energy system, such as liming the oceans? There is still time for a broad discussion on the unconventional forms that an ambitious climate protection policy might take, and for pursuing the corresponding technological options. The longer it takes to open such a debate, the greater is the risk that the Paris climate targets will slip out of reach. Dr Oliver Geden is Head of Research Division EU/Europe at the German Institute for International and Security Affairs (Stiftung Wissenschaft und Politik, SWP), Berlin. Dr Stefan Schäfer is Programme Leader at the Institute for Advanced Sustainability Studies (IASS), Potsdam. This article is based on a paper published by SWP in December 2016.
Padmanabhan M.,Leibniz University of Hanover |
Jungcurt S.,Institute for Advanced Sustainability Studies
Ecological Economics | Year: 2012
Institutions for biodiversity governance are located at the interface of human and ecological systems. The analysis of such institutions is challenged due to addressing a multitude of complex interactions between these two systems occurring at different natural scales and levels of human organization. Due to this complexity, empirical analysis of biodiversity management often leads to context-specific explanations, providing little scope for comparative work or the development of more generalised, theory-based accounts. We aim at reducing complexity in understanding human-biodiversity relations, making cases comparable across sites, and propose that, in order to address complexity, we need a method of abstraction that leads to the development of a more structured analysis, based on selection of explanatory factors according to cconceptual models as well as empirical significance. We suggest that the stylisation of typical "resource use-perspectives" - the combination of typical transactions that are inextricably linked by the interest of the actor - can be a useful method for realizing appropriate model selection. In this paper, we provide an account of how use-perspectives can be developed and to what kind of analysis they can contribute, using the example of agrobiodiversity in grain as seed, food, or genetic material. © 2012 Elsevier B.V.
Morel J.L.,CNRS Soil and Environment Laboratory |
Chenu C.,Agro ParisTech |
Lorenz K.,Institute for Advanced Sustainability Studies |
Lorenz K.,Ohio State University
Journal of Soils and Sediments | Year: 2015
Purpose: The sustainable use and management of global soils is one of the greatest challenges for the future. In the urban ecosystem, soils play an essential role with their functions and ecosystem services. However, they are still poorly taken into consideration to enhance the sustainable development of urban ecosystems. This paper proposes a categorization of soils of urbanized areas, i.e., areas strongly affected by human activities, according to their ecosystem services. Materials and methods: Focus is put first on ecosystem services provided by non-urban soils. Then, the characteristics and number of services provided by soil groups of urbanized areas and their importance are given for each soil group. Results and discussion: Soils of urbanized areas are here defined as SUITMAs, because they include soils of urban, sensu stricto, industrial, traffic, mining, and military areas. This definition refers to a large number of soil types of strongly anthropized areas. SUITMAs were organized in four soil groups, i.e., (1) pseudo-natural soils, (2) vegetated engineered soils, (3) dumping site soils, and (4) sealed soils. For each soil group, examples for ecosystem services were given, evaluated, and ranked. Conclusions: This proposal contributes to foster the dialogue between urban spatial planning and soil scientists to improve both soil science in the city and recognition of SUITMAs regarding their role for the sustainable development of urban ecosystems and, in particular, to enhance multifunctional soils in urban areas. © 2014, Springer-Verlag Berlin Heidelberg.
Butler T.,Institute for Advanced Sustainability Studies
NATO Science for Peace and Security Series C: Environmental Security | Year: 2013
Megacities and other large urban areas can often be associated with poor air quality. In the developed world, stricter emissions control legislation has resulted in dramatic improvements in urban air quality. Future emissions scenarios project that this will also spread to the developing world. A result of this will be that air quality in urban areas will become more influenced by emissions from outside of these areas. © Springer Science+Business Media Dordrecht 2013.