Energy and Environment

Neutrons are an excellent tool for the non-destructive imaging the interior of objects. They can provide a valuable complement to the more widely used x ray radiography. For some materials that are virtually opaque or for those that cannot be distinguished by X-rays, neutrons provide the only informative ‘dissection tool‘. However, neutron radiography is mainly confined to the laboratory and fixed facilities, because neutron generation relies on equipment like nuclear reactors or particle accelerators, which are costly, complex and cannot be moved. Scientists at the Laboratory for Thermohydraulics at the Paul Scherrer Institute PSI want to develop a more flexible imaging technique based on fast neutrons.

The life cycle inventory database ecoinvent forms the basis for life cycle assessment projects, eco-design, and product environmental information. Since 2003, ecoinvent has enabled companies to manufacture their products more in harmony with the environment, policymakers to implement new policies, and consumers to adopt more environmentally friendly behaviour. The new version 3.0 is a further milestone in life cycle assessment: new and updated data offer ecoinvent users a greater number of possible applications in the areas of e.g. chemical production, foodstuffs, vegetables and electricity.

Household waste always used to end up left untreated in landfills, and the effects of this practice are well-known: these waste disposal sites were quite often ecological "death zones". With the incineration of municipal waste, there was some mitigation of this problem: despite the overall increase in quantities of waste, the areas claimed by landfill have been limited in recent decades thanks to waste recycling and incineration. However, waste incineration remains far from a panacea. Some combustion products that are already present in the burnt materials or that arise just during the combustion process itself are harmful to human health and the environment and some of them still find their way out of waste incineration plants and into landfill sites as their final destination.

Megacities are often perceived by the public to be major sources of air pollution, which affect their surroundings as well. However, recent studies show that the environmental credentials of cities with over one million inhabitants are not so bad after all. An international team of researchers, including scientists from the Paul Scherrer Institute (PSI), has now confirmed, on the basis of aerosol measurements carried out in Paris, that so-called post-industrial cities affect the air quality of their immediate surroundings far less than might be thought.

For the discovery and characterisation of the miraculous material graphene à a layer of carbon exactly 1 atom thickà two Russian born physicists were awarded the Nobel Prize in 2010 and got a huge amount of media attention. Ever since graphene was first isolated, scientists all over the world have been rushing to find applications. Recently, scientists at the Paul Scherrer Institute PSI laid the foundations for a graphene-based super capacitor. With its help, the lifespan of batteries in hybrid cars could be extended significantly

Lithium-ion batteries are high performance energy storage devices used in many commercial electronic appliances. Certainly, they can store a large amount of energy in a relatively small volume. They have also previously been widely believed to exhibit no memory effect. That’s how experts call a deviation in the working voltage of the battery, caused by incomplete charging or discharging, that can lead to only part of the stored energy being available and an inability to determine the charge level of the battery reliably. Scientists at the Paul Scherrer Institute PSI, together with colleagues from the Toyota Research Laboratories in Japan have now however discovered that a widely-used type of lithium-ion battery has a memory effect. This discovery is of particularly high relevance for advances towards using lithium-ion batteries in the electric vehicle market. The work was published today in the scientific journal Nature Materials.

Exhaust gases produced by diesel combustion are freed from harmful nitrogen oxides with the aid of an aqueous urea solution. That’s the state of the art. The urea decomposes into ammonia and this, in turn, reduces the nitrogen oxides into harmless nitrogen. However, the urea solution can produce undesirable solid residues and, in addition, freeze in extremely cold weather. Now researchers at the Paul Scherrer Institut (PSI) have developed a catalyst which can be used with better reducing agents than urea for nitrogen oxide reduction.

In nighttime photographs taken from space, the large cities of the world can easily be recognised by the flood of their public lighting. However, probably only the trained eye is able to see, as well as New York or Tokyo, the locations of many oil-producing wells . The light in these cases originates mainly from the combustion of methane. This huge waste of an energy-rich gas has devastating economic and ecological consequences. Reasearchers at the Paul Scherrer Institute PSI are looking for a solution: the conversion of methane into the liquid energy carrier methanol

Researchers in the Energy Economics Group at the Paul Scherrer Institute PSI have used their model of the Swiss electricity system —called STEM-E — to analyze various electricity supply scenarios. They have concluded that alternatives to today's electricity supply are associated with different costs, risks and opportunities. Realising sustainability objectives such as climate protection while phasing out nuclear generation and making Switzerland's electricity supply independent of foreign countries raises many challenges. Furthermore, their analysis suggests that costs of electricity production are likely to increase by at least 50 percent by 2050

Lithium-ion batteries are one of today's best technologies for storing electrochemical energy. They have a high energy density and specific energy and a sufficiently long lifetime to allow them to be used in microelectronic devices and cars. The commercial rise of Li-ion batteries in the last two decades is impressive. However, further improvements are possible and this is a field in which researchers at the Paul Scherrer Institute (PSI) are working. Nevertheless, the potential of the Li-ion battery is limited chemically and it will only be possible to achieve an even higher energy density, which is crucial for electric mobility in particular, by using other new types of batteries.

Ice and snow have fundamental significance for our climate. Generally speaking, one assumes that science knows everything that is important about such everyday phenomena. Yet, as soon as one looks at the whole at the molecular level, many questions remain unanswered. This knowledge is essential for predicting the future of our planet. Thorsten Bartels-Rausch in an interview about the great unknowns.

Switzerland is facing a potentially radical restructuring of its energy system in the light of the Federal Government's Energy Strategy 2050. One particular challenge associated with achieving the goals of the Strategy is realizing an electricity supply sector that responds to uncertain developments in electricity demand, national climate targets and the decision to phase out nuclear power. In order to investigate options for this transformation of the electricity sector, researchers at the Paul Scherrer Institute (PSI) are developing and analyzing a range of alternative scenarios of the future electricity system in Switzerland. These scenarios are developed, quantified and explored with an analytical tool built at PSI that simultaneously examines long-term developments (to 2050 and beyond) while accounting for seasonal and daytime fluctuations in electricity demand and supply.

Researchers at the Paul Scherrer Institute PSI have gained valuable insights into one of the most common ageing mechanisms of polymer electrolyte membranes in hydrogen fuel cells. The robustness of these membranes is crucial in determining the lifespan of a fuel cell. The new findings contribute to longer-lasting cells by a better understanding of one of the main challenges for the commercialisation of these clean energy converters.

The Institute of Biomass and Resource Efficiency was founded by the two institutions, PSI (Paul Scherrer Institute) and FHNW (University of Applied Sciences Northwestern Switzerland), at the start of 2013. The aim of this new institute is to tackle the issue of resource efficiency throughout Switzerland, concentrating simultaneously on energy and material for the first time, and to thus make a significant contribution to the Federal Government’s "Energy Strategy 2050". The focus is on the sustainable use of biomass.

In many European countries, gas and steam power plants (CCGT plants), also known as combined cycle power plants, are included as options for a safe energy supply. In the 2050 Federal Government Energy Strategy, they are mentioned as a possible replacement for the nuclear power plants that are being phased àout. Combined cycle power plants convert natural gas into electricity using a combination of gas and steam turbines, with very high efficiencies, of around 60 percent. Furthermore, since these power plants can be started up and shut down very quickly, they are ideally suited for compensating production fluctuations from wind and solar power plants. However, their CO₂ emissions, whilst the lowest of all conventional power plants using fossil fuels, are still significant. Researchers at the Paul Scherrer Institute are working on a solution for this within the framework of a European Union project.

Cement holds the world’s buildings together. The binding agent for concrete and other construction materials is, if assessed by global production volumes, one of the world’s most important assets. However, cement production consumes vast amounts of energy à and this is largely obtained by the combustion of fossil fuels. Scientists at the Paul Scherrer Institute and the globally-active Swiss cement manufacturer Holcim want to change this.

Der neue Energie-Spiegel ist da.Mit der neuen Energiepolitik kommen grosse Veränderungen auf die Schweizer Stromversorgung zu. Werden erneuerbare Energiequellen genug Strom produzieren, um nach dem Aus der Kernkraftwerke unseren Verbrauch zu decken? Oder müssen wir uns in Zukunft auf Gaskraftwerke und Stromimporte verlassen? Und wie wirkt sich die neue Energiepolitik auf die CO₂-Bilanz und die Stromkosten aus? Diese Fragen versucht die neueste Ausgabe des Energie-Spiegels zu beantworten.This news release is only available in German.

Das PSI ist in der Jubiläumsausstellung auf dem Jungfraujoch prominent vertreten75 Jahre Sphinx-Observatoirum und 100 Jahre Jungfraubahnen: Dies ist der Anlass für eine Ausstellung der internationalen Stiftung Hochalpine Forschungsstationen Jungfraujoch und Gornergrat, die im Frühjahr eröffnet wurde.This news release is only available in German.

A research team from the Paul Scherrer Institute has reconstructed the concentration record of lead in the atmosphere in Russia since 1680. The results demonstrate a significant increase in the atmospheric lead concentrations since the 1930s and a significant reduction since the 1970s.

Die Energiewende als politischer Wille ist Realität, aber wie wird die Schweiz ihre Energieversorgung aus dem heutigen Stand in diejenige überführen, die die für das Jahr 2050 formulierten Ziele erfüllt? Mit Fragen der Umsetzung, mit den Optionen und den Herausforderungen des beschlossenen Umbaus der schweizerischen Energielandschaft befasste sich am 14. Mai 2012 die Energietagung des Paul Scherrer Institut. Im Mittelpunkt stand der bei einer zunehmend dezentralen Energieversorgung notwendige Umbau der Stromnetze.This news release is only available in German.