Newsletter PS-Park 'n' Science, 5th edition, Dec 2010
English text version of the Park'n'Science newsletterTable of Contents
An alliance for more efficiency
Saving electricity and enhancing freedom of design
Heating offices with the earth's temperature
Casting young energy crops
Park ‘n’ Life
New Energies at the Science Park
Be honest - have you already replaced the old fairy lights for the Christmas tree with a modern energy-efficient LED chain? At the very latest, the EU regulation on light bulbs has made it clear that a comprehensive energy saving plan must take into account even the smallest contributions in order to achieve the potential savings of 20% in present energy consumption through intelligent measures. To produce the remaining 80% of current energy demand in a sustainable way also requires a lot of detailed work in research and development, not to mention issues of electricity storage and transmission. Power supply based on renewable energies must make optimal use of all existent resources energy mix and efficiency.
The Science Year of Energy which highlighted these issues is coming to an end. On this occasion, PS addressed the question of whether the subject of energy also plays a role at the Potsdam-Golm Science Park. Examples involving the keyword "energy mix" as well as basic optimization and detailed development were quickly found. See for yourself in this edition which offers a number of energy-related activities at the Potsdam-Golm Science Park: From heat production through geothermal energy, combined heat / power generation and energy crop cultivation to new light sources comprising OLEDs, impressive approaches in various stages of implementation are presented. In addition, an interdisciplinary project on solar cells combines the Science Park's skills with those of the wider research community.
Whether by candlelight or under an energy saving lamp, enjoy a relaxed holiday season and have a very happy 2011, which will be the Science Year of Health Research.
An alliance for more efficiency
Interdisciplinary solar cell research at the Potsdam-Golm Science Park.
The new solar cells are coated in an absence of air and moisture. The production of efficient solar cells requires properly defined environmental conditions. Here, a doctoral student from Prof. Neher's group at the Institute of Physics and Astronomy works in a nitrogen-filled glove box.
(Photo: Dr. Frank Jaiser)
Solar energy is becoming increasingly important as fossil fuel reserves dwindle. Besides increasing the energy efficiency of finished products, current research focuses on concepts for reducing energy and material consumption in the manufacture of solar cells. Of great interest here are thin-film cells based on organic semiconductors. Due to the very high absorption coefficient of the conjugated organic compounds used, incident sunlight is absorbed within a layer just a few hundred nanometres thick. Organic compounds also have a very low density of 1 g/cm3 (compared with conventional semiconductors such as silicon and germanium). A quantity of just one gram is therefore sufficient to completely cover an area of five square meters with a photo-active organic semiconductor. Against this background, the German Research Foundation (DFG) and the Federal Ministry of Education and Research (BMBF) have launched programs in recent years worth millions of euros for promoting research on organic solar cells.
Scientists at the Golm research site are involved in many aspects of these programs. The aim of the BMBF research alliance SOHyb (self-organization in organic hybrid solar cells) is to create a common concept of a hybrid organic solar cell by merging together three different approaches to converting solar energy into electrical energy. The related activities will be carried out mainly in Potsdam-Golm at the University of Potsdam's Institute of Physics and Astronomy (Prof. Dieter Neher), at the Fraunhofer Institute for Applied Polymer Research (Dr. Silvia Janietz) and the Max Planck Institute for Colloids and Interfaces (Prof. Helmuth Möhwald), in close cooperation with a group led by Dr. Konstantinos Fostiropoulos at the Berlin Helmholtz Centre for Materials and Energy, and a group led by Prof. Bernd Smarsly at the University of Giessen.
Furthermore, Prof. Neher’s group is involved in a joint project titled Developing PVcomB (development of the Berlin competence centre for thin films and nanotechnology in photovoltaics). The project will be sponsored with more than €12 million for a period of five years as part of the BMBF's initiative titled "Advanced Research and Innovation in the New German States". Scientists at the Institute of Physics and Astronomy in Potsdam have set an ambitious goal of combining organic semiconductors with amorphous silicon to develop novel hybrid cells significantly surpassing the efficiency of traditional thin-film cells.
What both joint projects have in common is that they break the boundaries between conventional methods of producing organic and inorganic solar cells in order to identify new ways of making solar cells more efficient. The researchers’ goals can only be attained through close collaboration between groups with different expertise in the physics and chemistry of organic and inorganic semiconductors. The Potsdam-Berlin area, with its multitude of university and non-university groups, offers an ideal setting for this purpose.
Saving electricity and enhancing freedom of design
OLEDs - the new light sources - are not only highly energy efficient but also extremely versatile in use.
(Photo: Fraunhofer AIP)
In addition to material properties such as strength and bio-degradability, the electro-optical properties of plastics are increasingly the focus of attention. If an electrical voltage is applied to certain organic materials, so they glow in defined colours. Scientists from the Fraunhofer Institute for Applied Polymer Research (IAP) are presently dealing with such OLEDs (Organic Light Emitting Diodes). PS spoke to Dr. Armin Wedel, head of the Department for Functional Polymer Systems.
PS: Which characteristics make OLEDs so interesting?
PS: Are there already some first applications for OLEDs?
PS: So these displays have not yet reached the size of common LCD units. Which issues remain to be resolved to enable a use of OLEDs on a larger scale?
PS: How do OLEDs contribute to saving energy?
PS: Which other fields of application do you consider promising?
PS: Thank you very much for your time!As he had completed chemistry as a special subject for the Abitur, Marco didn’t find the theoretical requirements in the vocational school difficult. However, Marlies Walter, training supervisor at IAP, stresses that passing the Abitur exam is not a prerequisite for obtaining a training place at IAP. Students who leave secondary school (Realschule) with good to very good grades in natural sciences have equally good chances. Once the practical foundations have been mastered at the vocational training centre in Adlershof for the first 10 months of training and the work groups have been integrated into the institute, the apprentices are already able to take on tasks within the projects; the scientists are then willing contacts for any questions about the demanding theoretical subject matter to be learnt.
Heating offices with the earth's temperature
Eleven years ago, the Max Planck Society in Brandenburg inaugurated three institutes at what is now the country's largest scientific centre, the Potsdam-Golm Science Park: The Max Planck Institutes of Colloids and Interfaces, Molecular Plant Physiology and for Gravitational Physics. One objective was clear from the start: Their power supply had to be innovative, sustainable and of a high capacity. High-performance technologies were needed to meet different requirements such as those concerning highly sensitive laboratory equipment.
The renewable energies initially focused on by the developers were soon discarded again. Examined next were the potentials of shallow geothermal energy, i.e. that occurring in the uppermost thousand meters of the earth's surface. A drilling test provided the following results: Ground water conditions distinguished by slow flow rates prove ideal for using the earth as a geothermal store. At high flow rates, heat is removed too quickly. The aim was to obtain the earth's heat for heating, and simultaneously store cold for usage in summer. The solution comprised a geothermal probe field with a heat pump and passive cooling.
Energy is today supplied by multiple, interacting components: Two co-generation power plants, a heat pump and a geothermal probe field for supplying heat; a geothermal probe, free-cooling and refrigeration machines for producing cold water. A boiler is available for handling peak loads. A cogeneration unit's high efficiency is attributable to the simultaneous production of heat and electrical energy. Rather than going waste, surplus heat energy released by the cogeneration plants in summer is "reused" in a climate friendly manner. An absorption refrigeration machine uses this energy to generate cold.
Much of the energy required for heating the indoor ventilation and air-conditioning systems in winter is obtained by the heat pump from the geothermal probe field. This creates a local heat sink or cold zone in the earth, allowing process plants to be cooled in the summer months. The waste heat arising during cooling of large equipment forms a high-temperature zone in the earth reservoir, thereby resulting in warming here. This higher temperature level enables effective operation of the heat pump in the winter months. The ventilation systems are cooled by free-cooling via outdoor air, and by refrigeration machines in summer.
In the meantime, depending on the annual temperature curve, about 50% of the heat energy needed for the ventilation and air-conditioning systems can be obtained from the underground reservoir. More than 60% of the process cooling capacity is obtained via the geothermal probe field and free-cooling. Compared with conventional solutions, use of the geothermal probe field reduces CO2 emissions by several thousand tons a year.
Facts and figures
The geothermal probe field covers an area of approximately 70 m x 50 m in which 160 bores each 100 metres deep are installed. Each bore contains two conduction loops comprising polyethylene. A water-glycol mixture serving as the transfer medium flows through the probes, the pressure conditions being monitored continuously in this process. On occurrence of an impermissibly high differential pressure, the water supply to the probe field is interrupted. In recent years, an average of 1300 MWh of energy have been generated annually by the probe field.
Casting young energy crops
New possibilities of early identifying potentials for biomass production in energy crops.
Biomass differences in coeval Arabidopsis thaliana lines.
Rising carbon dioxide concentrations in the atmosphere and the decrease in fossil fuel reserves such as oil, natural gas and coal make it imperative to develop alternative energy sources like wind, geothermal and solar energy.
Plants use sunlight to form high-energy organic materials from carbon dioxide, and could provide another source of alternative energy. This, however, requires energy crops that grow rapidly and generate a large biomass. To breed such energy crops, it is important to find indicators associated with biomass, which will allow reliable predictions of biomass while the plants are still young. This aspect is particularly important in the case of perennial cultures.
In cooperation with a number of partners, The Max Planck Institute of Molecular Plant Physiology has achieved initial success in this area. In various projects, researchers explored how plant growth is regulated. They reasoned that, as growth represents an integrated output of metabolic activity, there should be a relationship between the levels of metabolites in a plant and its rate of growth and final biomass.
To test this idea, they first analysed biomass and over 100 metabolites in a large number of genetically well-characterized lines of the model plant Arabidopsis thaliana. They found a highly significant correlation between biomass and a specific combination of metabolites, showing that the metabolic composition can be used as a biomarker for biomass.
Another project focused on the starch content instead of the entire range of metabolites. Some of the carbon absorbed during daytime photosynthesis is stored as starch which ensures continued plant growth during the night when no photosynthesis is possible. This project, too, examined variants of Arabidopsis thaliana differing greatly in their biomass. The surprising outcome of this work was that plants with the largest biomass had the lowest starch content in their leaves. Apparently, the plants showing better growth were capable of integrating the available carbon into their metabolism more efficiently than their smaller counterparts. Further studies showed that biomass is influenced by specific differences in the genetic sequence of two genes related to the carbohydrate status of plants.
These experimental approaches show that it is possible to find metabolic indicators for biomass in Arabidopsis thaliana. The implication is that it may be possible to use measurements of metabolites to identify plants which produce more biomass than others, and to prioritise them for further plant breeding. Additional investigations will show whether the detected indicators are universal, or whether they differ from one plant species to another, and / or depend on environmental conditions. The institute's ongoing research on corn which is not yet published is addressing these issues.
Not only behind closed door …
Modern doctoral training at international level at the University of Potsdam
Interdisciplinary dialogue and esteem shape the annual doctoral student symposia.
The restructuring of doctoral training was on the agenda a few years ago at the University of Potsdam, because in the past many doctorates had taken too long to complete or were not completed at all. This was one of the reasons for the founding of the Potsdam Graduate School (PoGS) at the end of 2006 (photo: Fritze). Today, it is an important contact point for around 1,500 doctoral students. The establishment sees itself as an umbrella organisation for the 23 doctoral programmes currently on offer across all the faculties. The Graduate School offers membership to all PhD candidates, with the aim of improving conditions for them at the University of Potsdam through transparent processes and more intensive supervision and support. Nevertheless, the students’ capacity for independent academic study continues to be an important objective and the dissertation naturally remains the key element for the conferral of a doctorate. PoGS also aims to reinforce research activities on the site and to make it more attractive to young researchers from Germany and overseas.
The programmes on offer include the “Junior Teaching Professionals” and “International Teaching Professionals” projects that were created as part of the University of Potsdam concept for teaching excellence and which won the “Excellence in Teaching” competition held by the Stifterverband für die deutsche Wissenschaft (the German industry initiative promoting science and learning). They offer young researchers the opportunity to gain qualifications in the area of academic teaching while they are working towards their doctorate.
The activities of the PoGS include the one-day, interdisciplinary PhD symposium held annually (this year on 14 October) for PhD candidates at the University of Potsdam, as well as for non-university research institutions. The symposium acts as a forum for young scientists at which the PhD candidates get the chance to present their dissertation projects as talks or posters to an interdisciplinary audience of specialists and to discuss any questions concerning content or methodology. As well as the scientific discussions, young researchers also get opportunities to make contacts and network. be •
The state of Brandenburg awards two young scientist prizes to researchers at Potsdam.The post-doctoral prize for humanities and the social sciences was awarded to Dr Markus Messling (34), a researcher in Romance studies at the University of Potsdam. Messling was awarded the 20,000 euro post-doctoral prize for humanities and the social sciences for the work of the “Philology and racism in the 19th century” Emmy Noether research group, which he leads. Together with three colleagues, he is investigating the “epistemological and ideological association of 19th century philology with racism and colonialism”.
He was awarded the 5,000 euro graduate award for his degree dissertation “Examination of the structure and chemical and thermal resistance of biogenic silicon dioxide”. Mike Neumann completed his Diplom in chemistry in less than nine semesters and with outstanding results. For the best degree completed in 2009/2010, he received the Jacob Jacobi prize awarded by the Faculty of Mathematics and Natural Sciences of the University of Potsdam. He is currently working as a doctoral student in the inorganic materials chemistry working group (Prof. Dr. Peter Strauch) at the University of Potsdam. He is also a deputy federal spokesperson for the JungChemikerForum der Gesellschaft Deutscher Chemiker (young chemists forum of the German Chemical Society).
The University of Potsdam also congratulates Niko Hildebrand (35), a professor in nano-biophotonics at the University of Paris-Sud 11 since October 2010. He received the 20,000 euro post-doctoral prize in the area of natural sciences and engineering. Hildebrand was awarded a doctorate in physical chemistry from the University of Potsdam in 2007 (Prof. Dr. Hans-Gerd Löhmannsröben). He was then employed at the Fraunhofer Institute for Applied Polymer Research as a group leader in an EU project from 2008 to 2010.