HZB Newsroom

Sear results - Keyword: Sustainability

  • <p>The world record cell (here in front of the electron storage ring BESSY II) has an area of about one square centimetre, a typical lab size.</p>
    News
    22.11.2021
    World record again at HZB: Almost 30 % efficiency for next-generation tandem solar cells
    Three HZB teams led by Prof. Christiane Becker, Prof. Bernd Stannowski and Prof. Steve Albrecht have jointly managed to increase the efficiency of perovskite silicon tandem solar cells fabricated completely at HZB to a new record value of 29.80 %. The value has now been officially certified and is documented in the NREL-charts. This brings the 30 percent mark within reach.

  • News
    18.11.2021
    Germany on the road to net zero: a new Web Atlas shows the options
    Which technical and nature-based options as well as political decisions can support Germany in being CO2-neutral? These questions are answered by the new web atlas of the Climate Service Center Germany (GERICS) at the Helmholtz-Zentrum Hereon. The new tool is aimed at politicians, experts and the public. The HZB has also contributed to the web atlas.

  • <p>Finely ground powders can also react with each other without solvents to form the desired product. This is the approach of mechanochemistry.</p>
    Science Highlight
    16.11.2021
    "Green" chemistry: BESSY II sheds light on mechanochemical synthesis
    In mechanochemistry, reagents are finely ground and mixed so that they combine to form the desired product, even without need for solvent. By eliminating solvent, this technology promises to contribute significantly towards ‘green’ and environmentally benign chemical manufacture in the future. However, there are still major gaps in understanding the key processes that occur during mechanical treatment and reaction. A team led by the Federal Institute for Materials Research (BAM) has now developed a method at BESSY II to observe these processes in situ with X-ray scattering. 

  • News
    12.11.2021
    Live broadcast at HZB - now as podcast!
    After a live broadcast the programme "Die Profis" is now online as a podcast.
  • <p>HZB is the first non-university research institution to be awarded the " Vielfalt gestalten " ("Shaping Diversity") certificate by the Stifterverband.<br /><br />(from left to right: Volker Meyer-Guckel, Deputy Secretary General of the Stifterverband, Jennifer Schevardo, HZB Project Manager Diversity Audit, Jan L&uuml;ning, scientific director at HZB).</p>
    News
    11.11.2021
    Stifterverband certifies Helmholtz Centre Berlin for strategies in dealing with diversity

    The Helmholtz-Zentrum Berlin (HZB) is the first non-university research institution to have undergone the Stifterverband's diversity audit "Vielfalt gestalten". The certification attests to the HZB's opportunity-oriented concepts and measures for diverse groups of people.

  • <p>Olga Kasian has accepted a professorship at the Friedrich-Alexander-Universit&auml;t Erlangen-N&uuml;rnberg (FAU).</p>
    News
    13.10.2021
    Friedrich-Alexander Universität Erlangen-Nürnberg appoints Olga Kasian
    Dr. Olga Kasian is investigating why catalysts for hydrogen production by water electrolysis are limited in efficiency. The chemist has now accepted a professorship at the Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU). The W2 professorship is entitled "Materials for Electrochemical Energy Conversion" and is located at the Faculty of Engineering.

  • <p>Five different types of defects in MAPI-perovskites were examined and characterised. The result: a large proportion of defects is not trapping the charge carriers for long.</p>
    Science Highlight
    07.10.2021
    Perovskite solar cells: Defects trap charge carriers - and release them again
    An international team at HZB and Charles University Prague has investigated how charge carriers in so called MAPI-perovskite semiconductors interact with different defects. They show that a large proportion of defects quickly releases trapped charge carriers. These results could help to further improve the properties of perovskite solar cells.

  • News
    21.09.2021
    BR50: How Berlin could be developed into a world-leading science metropolis
    On 26 September, not only the Bundestag but also the Berlin House of Representatives will be newly elected. In a position paper, the non-university institutions in the capital that are united in Berlin Research 50 now emphasise what is important for research after the election. In it, they outline 10 demands that the future Senate should implement in order to further strengthen Berlin as a science metropolis.



  • <p>Opened! Bernd Rech (l.) and Christian Rickerts (r.) pressed the symbolic red button to start the Real Lab in Adlershof on 6 September.</p>
    News
    07.09.2021
    HZB uses electricity-producing facade wall as real laboratory

    In the presence of the State Secretary for Economic Affairs, Energy and Operations of the State of Berlin, Christian Rickerts, the HZB officially commissioned the solar façade of a new research building on 6 September 2021. What makes it so special is that the elegant façade not only generates up to 50 kilowatts of electricity (peak power). It also provides important insights into the behaviour of the solar modules under different weather conditions.  

  • <p>The SAM layer between the perovskite semiconductor and the ITO contact consists of a single layer of organic molecules. The mechanisms by which this SAM layer reduces losses can be quantified by measuring the surface photovoltage and photoluminescence.</p>
    Science Highlight
    20.08.2021
    Perovskite solar cells: Interfacial loss mechanisms revealed

    Metal-organic perovskite materials promise low-cost and high-performance solar cells. Now a group at HZB managed to de-couple the different effects of self-assembled monolayers of organic molecules (SAMs) that reduce losses at the interfaces. Their results help to optimise such functional interlayers.

  • <p>The VSANS instrument (here in the neutron hall at BER II) will move to Penn State University.</p>
    News
    19.08.2021
    Neutron instrument VSANS will move to Penn State University, USA

    At the end of 2019, the Berlin neutron source BER II was shut down as scheduled. To ensure that the high-quality instruments can continue to be used for research, they are moving to suitable neutron sources in Germany and abroad. Now, another move has been agreed upon: The Very Small Angle Scattering Instrument (VSANS) will find a new home at the Breazeale Research Reactor at Penn State University, USA, in spring 2022.

  • Science Highlight
    09.08.2021
    Green hydrogen: Why do certain catalysts improve in operation?
    Crystalline cobalt arsenide is a catalyst that generates oxygen during electrolytic water splitting in the production of hydrogen. The material is considered to be a model system for an important group of catalysts whose performance increases under certain conditions in the course of electrolysis. Now a HZB-team headed by Marcel Risch has observed at BESSY II how two simultaneous mechanisms are responsible for this. The catalytic activity of the individual catalysis centres decreases in the course of electrolysis, but at the same time the morphology of the catalyst layer also changes. Under favourable conditions, considerably more catalysis centres come into contact with the electrolyte as a result, so that the overall performance of the catalyst increases.

  • <p>In polar regions and at high altitudes the conversion of solar radiation into hydrogen could certainly be worthwhile.</p> <p></p>
    Science Highlight
    02.07.2021
    Solar hydrogen for Antarctica - study shows advantages of thermally coupled approach
    A team from the Helmholtz-Zentrum Berlin, Ulm University, and Heidelberg University has now investigated how hydrogen can be produced at the South Pole using sunlight, and which method is the most promising. Their conclusion: in extremely cold regions, it can be considerably more efficient to attach the PV modules directly to the electrolyser, i.e. to thermally couple them. This is because the waste heat from the PV modules increases the efficiency of electrolysis in this environment. The results of this study, which has now been published in Energy & Environmental Science, are also relevant for other cold regions on Earth, such as Alaska, Canada, and high mountain regions, for example. In these places, solar hydrogen could replace fossil fuels such as oil and petrol.

  • <p></p> <p>VIPERLAB is funded under the European Programme for Research and Innovation Horizon 2020 (Grant No 101006715).</p> <p></p>
    News
    24.06.2021
    VIPERLAB: EU project aims to boost perovskite solar industry in Europe
    The HZB is coordinating a major European collaborative project to open up new opportunities for the European solar industry. The VIPERLAB project involves 15 renowned research institutions from Europe, as well as Switzerland and Great Britain. It will be funded within the framework of the EU's Horizon 2020 programme for the next three and a half years with a total of 5.5 million euros, from which the HZB will receive just under 840,000 euros. 

  • <p>Using Small-Angle Scattering the early stages of structure formation in precursor solutions of perovskite solar cells have been explored.</p>
    Science Highlight
    18.06.2021
    Perovskite Solar Cells: Insights into early stages of structure formation
    Using small-angle scattering at the PTB X-ray beamline of BESSY II, an HZB team was able to experimentally investigate the colloidal chemistry of perovskite precursor solutions used for solar cell production. The results contribute to the targeted and systematic optimization of the manufacturing process and quality of these exciting semiconductor materials.

  • <p>CIGS PV modules are integrated into the fa&ccedil;ade of the HZB testing hall in Berlin-Adlershof. A team analyses the yield and development of the modules under real conditions.</p>
    News
    23.04.2021
    Berlin Energy Days: Integrated photovoltaics - active areas for the energy transition
    The energy transition needs photovoltaics, and photovoltaics need space. There are large areas that have hardly been used so far: For example, solar cells can be integrated into the shell of buildings and vehicles, or installed in traffic routes, over farmland and flooded opencast mines. On Wednesday, 28 April 2021, experts from the HZB consulting office for builiding integrated PV (BAIP) and other research institutions will present these options. The event will take place as part of the Berlin Energy Days, and participation is free of charge after registration.
  • <p>The HZB team was able to determine the photoconductivity in the thin layers of rust using time-resolved microwave measurements; here is a picture of the measurement setup.</p>
    Science Highlight
    19.04.2021
    Green hydrogen: "Rust" as a photoanode and its limits
    Metal oxides such as rust are intriguing photoelectrode materials for the production of green hydrogen with sunlight. They are cheap and abundant, but in spite of decades of research, progress has been limited. A team at HZB, together with partners from Ben Gurion University and the Technion, Israel, has now analysed the optoelectronic properties of rust (haematite) and other metal oxides in unprecedented detail. Their results show that the maximum achievable efficiency of haematite electrodes is significantly lower than previously assumed. The study demonstrates ways to assess new photoelectrode materials more realistically.

  • <p></p> <p>A conductive AFM tip is used to scan the sample surface of an a-Si:H/c-Si interface under ultra-high vacuum on the nm scale, revealing the transport channels of the charge carriers via defects in the a-Si:H (red states in the magnified section).</p> <p></p>
    Science Highlight
    17.03.2021
    Solar cells: Losses made visible on the nanoscale
    Solar cells made of crystalline silicon achieve peak efficiencies, especially in combination with selective contacts made of amorphous silicon (a-Si:H). However, their efficiency is limited by losses in these contact layers. Now, for the first time, a team at Helmholtz-Zentrum Berlin (HZB) and the University of Utah, USA, has experimentally shown how such contact layers generate loss currents on the nanometre scale and what their physical origin is. Using a conductive atomic force microscope, they scanned the solar cell surfaces in ultra-high vacuum and detected tiny, nanometre-sized channels for the detrimental dark currents, which are due to disorder in the a-Si:H layer.

  • <p>The new audit logo for long-time certified companies</p>
    News
    17.03.2021
    HZB re-certified as a compatibility-friendly company again
    HZB has been certified as a family-friendly employer since 2011. Now the research centre has successfully completed the re-auditing process and developed further measures to promote a life phase conscious working culture. The certificate is considered a seal of quality for the company's compatibility policy and is awarded by the board of trustees of berufundfamilie Service GmbH.
  • News
    04.02.2021
    The HZB Graduate Center is here now
    The HZB “DR coordination” is now the HZB Graduate Center. Since the beginning of 2018, the DR coordination has been continuously expanding the offers and standards at the HZB for doctoral researchers and their advisors. The ideas and suggestions that were collected in discussions with numerous stakeholders and in various HZB committees on this topic are leading the path and are incorporated in the set up of a uniform HZB-wide umbrella structure for doctoral researchers and their advisors - the HZB Graduate Center.

  • <p>TEM-Image of a &alpha;-SnWO<sub>4 </sub>film (pink) coated with 20 nm NiO<sub>x </sub>(green). At the interface of &alpha;-SnWO<sub>4</sub> and NiO<sub>x</sub> an additional interfacial layer can be observed.</p>
    Science Highlight
    26.01.2021
    Solar hydrogen: Photoanodes made of α-SnWO4 promise high efficiencies
    Photoanodes made of metal oxides are considered to be a viable solution for the production of hydrogen with sunlight. α-SnWO4 has optimal electronic properties for photoelectrochemical water splitting with sunlight, but corrodes easily. Protective layers of nickel oxide prevent corrosion, but reduce the photovoltage and limit the efficiency. Now a team at HZB has investigated at BESSY II what happens at the interface between the photoanode and the protective layer. Combined with theoretical methods, the measurement data reveal the presence of an oxide layer that impairs the efficiency of the photoanode.


  • <p>Part of the IRIS research labs will be equipped for research on catalysts. Photo</p>
    News
    25.01.2021
    HZB and Humboldt University agree to set up a catalysis laboratory
    Helmholtz-Zentrum Berlin (HZB) and Humboldt-Universität zu Berlin (HU) have signed a cooperation agreement with the aim of establishing a joint research laboratory for catalysis in the IRIS research building of HU in Adlershof. The IRIS research building offers optimal conditions for the research and development of complex material systems.

  • <p>The illustration visualizes the composition of the tandem solar cell.</p>
    Science Highlight
    11.12.2020
    Perovskite/silicon tandem solar cells on the threshold of 30% efficiency
    An HZB team has published a report in the journal Science on the development of its current world record of 29.15% efficiency for a tandem solar cell made of perovskite and silicon. The tandem cell provided stable performance for 300 hours – even without encapsulation. To accomplish this, the group headed by Prof. Steve Albrecht investigated physical processes at the interfaces to improve the transport of the charge carriers.

  • <p>1st Place: h4a Gessert + Randecker Architekten</p>
    News
    07.12.2020
    Architectural Design drafts for new CatLab Center awarded
    An innovative laboratory and office building for catalysis research will be built in Berlin-Adlershof: CatLab is to become an international beacon for catalysis research and drive forward the development of novel catalyst materials, which are urgently required for the production of green hydrogen for the energy transition. In an architectural competition four winning designs have now been selected. All designs include climate friendly solutions.

  • <p>Schematic illustration: the solvants (ink) are used to produce a thin film of polycrystalline perovskite.&nbsp;</p>
    Science Highlight
    27.11.2020
    Perovskite Solar Cells: paving the way for rational ink design for industrial-scale manufacturing
    For the production of high-quality metal-halide perovskite thin-films for large area photovoltaic modules often optimized inks are used which contain a mixture of solvents. An HZB team at BESSY II has now analysed the crystallisation processes within such mixtures. A model has also been developed to assess the kinetics of the crystallisation processes for different solvent mixtures. The results are of high importance for the further development of perovskite inks for industrial-scale deposition processes of these semiconductors.

  • <p>The distribution of local pH change (&Delta;pH) with time in an electrolyte containing 0.5 M K<sub>2</sub>SO<sub>4.</sub></p>
    Science Highlight
    19.11.2020
    Green hydrogen: buoyancy-driven convection in the electrolyte
    Hydrogen produced by using solar energy could contribute to a climate neutral energy system of the future. But there are hurdles on the way from laboratory scale to large-scale implementation. A team at HZB has now presented a method to visualise convection in the electrolyte and to reliably simulate it in advance with a multiphysics model. The results can support the design and scaling up of this technology and have been published in the renowned journal Energy and Environmental Science.

  • <p>Nine samples with mixtures from CsPbBr<sub>2</sub>I (ink 1, left) to pure CsPbI<sub>3</sub> (ink 2 right).</p>
    Science Highlight
    16.11.2020
    Solar cells: Mapping the landscape of Caesium based inorganic halide perovskites
    Scientists at HZB have printed and explored different compositions of caesium based halide perovskites (CsPb(BrxI1−x)3 (0 ≤ x ≤ 1)). In a temperature range between room temperature and 300 Celsius, they observe structural phase transitions influencing the electronic properties. The study provides a quick and easy method to assess new compositions of perovskite materials in order to identify candidates for applications in thin film solar cells and optoelectronic devices.

  • <p>This is how the extension hall will look after the scaffolding has been removed. The blue modules enclose the building like a bracket.</p>
    News
    24.09.2020
    Solar-cell façade at HZB undergoes real-life testing
    Solar-modules shimmer bright blue on the cladding of a new building at the Helmholtz-Zentrum Berlin (HZB). They are special CIGS thin-film modules custom-developed and produced in Germany for integration into the building’s envelope. The solar cladding not only meets part of the power requirement, but is also a realistic laboratory in and of itself: an HZB team is monitoring the long-term behaviour of the modules under varying environmental conditions and evaluating the data. 

  • <p>"I am convinced that we must act on climate change to prevent dramatic developments," says Bernd Rech. The technologies are available, and research is already working on further options. You can start the video by clicking the picture.</p>
    News
    23.09.2020
    Climate Strike on Friday: HZB-Direktor welcomes engagement for climate protection
    "I find it remarkable and encouraging that more and more citizens are joining the protests of the younger generation and calling for a turnaround for climate protection," says Prof. Bernd Rech, Scientific Director of the Helmholtz-Zentrum Berlin (HZB). In an open video message on the occasion of the worldwide climate day planned for Friday, he welcomes the fact that HZB staff members want to participate in the actions. At the same time he calls on people not to be afraid of technical changes. "The technologies for a climate-friendly energy supply are available. We must now use them quickly, but we must also improve them and create new options".

  • News
    21.09.2020
    HZB is member of the IGAFA initiative in Adlershof

    Since September 2020, the Helmholtz-Zentrum Berlin is again a member of IGAFA - the Initiative of Non-University Research Institutions in Adlershof. Prof. Dr. Jan Lüning, scientific director of the HZB, was elected to the association's board.

  • <p>Dr. Tristat Petit receives the ERC Starting Grant from the European Research Council for his research on a new class of materials for the storage of electrical energy, the so-called MXenes.</p>
    News
    03.09.2020
    New Materials for Energy Storage: ERC Starting Grant for Tristan Petit
    Dr. Tristan Petit has received a prestigious Starting Grant from the European Research Council for 1.5 million euros over the next five years. The materials researcher will use the grant to investigate a new class of materials known as MXenes for storing electrical energy. MXenes can store and deliver large amounts of electrical energy extremely quickly. They might play an important role in energy storage alongside batteries and supercapacitors. The ERC Starting Grant is one of the most important European research grants.

  • <p>Integrated PV-EC device during performance tests in the outdoor test bed for realistic operating condition.</p>
    News
    04.08.2020
    Best electrolyser/photovoltaics combinations demonstrated in test fields
    One of the most promising ways to increase the availability of solar energy is to convert excess production into hydrogen. The PECSYS project has investigated the best possible material and technology combinations to facilitate such an operation.

  • <p>Grosspeter Tower, Basel 2016</p>
    Nachricht
    16.07.2020
    Seminar für Architekt*innen Bauwerkintegrierte Photovoltaik: Architektur – Gestaltung und Ausführung
    Im September veranstaltet die Beratungsstelle für bauwerkintegrierte Photovoltaik (BIPV) „BAIP“ zusammen mit der Architektenkammer Niedersachsen ein Seminar für Architekt*innen zum Thema Bauwerkintegrierte Photovoltaik: Architektur-Gestaltung und Ausführung
  • News
    09.07.2020
    Facts, Research, Expertise: Helmholtz Climate Initiative starts new website

    The Helmholtz Climate Initiative has intensively reworked its website. Starting immediately, the Initiative now offers articles, background knowledge, fact sheets, and much more on the current state of climate research at www.helmholtz-klima.de. In a new expert inquiry, the Initiative connects with Helmholtz climate scientists. The Helmholtz-Zentrum Berlin (HZB) contributes research on the conversion of CO2 into fuels and basic materials to reach the goal of "Net Zero 2050".

  • <p>The new CatLab (blue area) will be built in close proximity to BESSY II and other laboratories.</p>
    News
    08.07.2020
    Launch of new catalysis centre in HZB-Adlershof
    The Helmholtz-Zentrum Berlin (HZB) is launching a major new project through an interdisciplinary architectural competition: an innovative laboratory and office building for expanding joint catalysis research between the HZB and the Max Planck Society (MPS). Catlab is to become an international beacon for catalysis research that will advance the development of novel catalyst materials urgently needed for the energy transition.

  • News
    15.05.2020
    They are back: Sheep and goats graze the Wannsee campus again

    The meadows are lush green, the ice saints (almost) over: Now is the perfect time for the sheep and goats to return from their winter quarters! Until late autumn, they will now graze the near-natural HZB campus in Wannsee and serve the natural preservation of the landscape - completely without a lawn mower.

  • News
    14.05.2020
    New charging points for electric cars installed in Adlershof
    On 14 May 2020, two charging points for electric cars were installed near the BESSY II main building. But not only the hybrid company car fleet is to be charged here. Soon, employees will also have the opportunity to charge their private cars at one of the charging points.

  • <p>The illustration shows the changes in the structure of FASnI<sub>3</sub>:PEACl films during treatment at different temperatures.</p>
    Science Highlight
    11.05.2020
    On the road to non-toxic and stable perovskite solar cells
    The promising halide perovskite materials for solar energy conversion show high efficiencies, but this comes at a cost: The best perovskite materials incorporate toxic lead which poses a hazard to the environment. To replace lead by less toxic elements is not easy since lead-free perovskites show lower stability and poor efficiencies. Now, an international collaboration has engineered a new hybrid perovskite material with promising efficiency and stability.
  • <p>The CIGS-Pero tandem cell was realised in a typical lab size of 1 square centimeter.</p>
    Science Highlight
    14.04.2020
    Tandem solar cell world record: New branch in the NREL chart
    A special branch in the famous NREL-chart for solar cell world records refers to a newly developed tandem solar cell by HZB teams. The world-record cell combines the semiconductors perovskite and CIGS to a monolithic "two-terminal" tandem cell. Due to the thin-film technologies used, such tandem cells survive much longer in space and can even be produced on flexible films. The new tandem cell achieves a certified efficiency of 24.16 percent.
  • News
    27.03.2020
    HZB donates urgently needed protective equipment for doctors’ surgery
    The situation in Berlin's doctors’ surgery is becoming increasingly acute due to the lack of important protective clothing and disinfectants. Some practices have already had to close for this reason. The HZB has therefore decided to provide quick help and is donating 65 boxes of protective clothing that are normally used for work in the laboratories and clean rooms. The boxes were handed over to the Kassenärztliche Vereinigung Berlin on 27.03.2020.
  • <p>MXenes are 2D materials forming multi-layered particles (left) from which pseudocapacitors are made. Shining X-ray light on MXenes revealed changes of their chemical structure upon intercalation of urea molecules (right) compared to pristine MXenes (center).</p>
    Science Highlight
    02.03.2020
    Fast and furious: New class of 2D materials stores electrical energy
    Two dimensional titanium carbides, so-called MXenes, are being discussed as candidates for the rapid storage of electrical energy. Like a battery,MXenes can store large amounts of electrical energy through electrochemical reactions- but unlike batteries,can be charged and discharged in a matter of seconds. In collaboration with Drexel University, a team at HZB showed that the intercalation of urea molecules between the MXene layers can increase the capacity of such "pseudo-capacitors" by more than 50 percent. At BESSY II they have analysed how changes of the MXene surface chemistry after urea intercalation are responsible for this.
  • Nachricht
    20.02.2020
    Berlins außeruniversitäre Forschungseinrichtungen schließen sich zusammen
    Berlin als internationale Wissenschaftsmetropole zu stärken, ist Ziel einer gemeinsamen Initiative der außeruniversitären Forschungseinrichtungen der Hauptstadt. Sie haben sich zur BR 50 (Berlin Research 50) zusammengeschlossen, um künftig gemeinsam Strategien für die Forschung und den Austausch mit Politik und Gesellschaft zu entwickeln. Auch das Helmholtz-Zentrum Berlin hat sich der Initiative angeschlossen. Die Kooperation mit den Berliner Universitäten wird hierdurch erleichtert und verstärkt.
  • News
    28.01.2020
    Unique X-ray experiments for school classes: The X-ray mobile will arrive at the HZB
    What is ultraviolet radiation? What are X-rays used for? And what is radioactivity again? These questions are on the curriculum in physics lessons, but vivid experiments on these topics are rare. From 5 to 13 March 2020, pupils can conduct experiments on these topics in the HZB's school laboratory in Berlin-Adlershof. The public is invited to attend on 12 March.
  • <p>Mint plants have been analysed after having grown on contaminated soil samples.</p>
    Science Highlight
    21.01.2020
    Plants absorb lead from perovskite solar cells more than expected
    Lead from metal-organic perovskite compounds can be absorbed particularly easily by plants. The bioavailability is significantly higher than that of lead from inorganic compounds as found in batteries. This is shown in a study by HZB researcher Antonio Abate with partners in China and Italy, published in Nature communications.
  • News
    09.01.2020
    HZB is now using green electricity
    Since 1 January 2020, HZB is drawing 100 per cent of its electricity from renewable energies. This reduces CO2 emissions by around 17,400 tons per year (related to 2018). By switching to green electricity, HZB acknowledges its responsibility to contribute to climate protection.