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Into the Future with Metrology - The Challenges of Energy

The Challenges of Energy

Metrology for energy carriers and energy storage

Metrology for energy carriers and energy storage The aim of the German federal government is to ensure that in 2050, the share of renewable energies will amount to at least 80 percent of Germany’s gross electricity consumption. The intention is to achieve this primarily by means of wind and solar energy. In order to balance out the fluctuations in the generation of electricity caused by varying weather conditions, large energy storage systems will be required in the future. If the energy transition is to be successful, energy carriers are required which will facilitate the use of the energy generated by renewables in different sectors, e.g. in the mobility sector and in the heat supply sector.

In close cooperation with partners from industry and with universities, research institutes and other national metrology institutes, PTB is not only carrying out basic research on the properties of new types of batteries, but also research on practical applications which are geared to the current needs of industry and society. This includes investigations in the fields of electromobility and stationary storage systems in private households. Since it is the gas grid in particular which is considered to be a potential storage facility for enormous amounts of energy – primarily in connection with hydrogen – PTB is also specifically extending its competence in the field of gas measurement technology.

PTB’s competence: battery research

Ideally, a battery management system will, in the future, provide information about the state of charge of a battery, its state of health and its thermal load under operating conditions. This will, however, only be safely achieved if the interdisciplinary task of understanding the complex system of a battery is solved by investigating electrochemical parameters, battery aging, state variables and charging characteristics. Here, PTB is involved with a large number of measurement technique developments and research projects, for example:

• In the European Opens external link in new window“LiBforSecUse” research project, PTB is coordinating a consortium of partners from industry and from research and metrology institutes with the aim of developing a measuring method which can efficiently measure the residual capacity of lithium-ion batteries from electric vehicles for second-use applications. Although the life cycle of batteries used in electric vehicles ends when the batteries have reached a residual capacity of about 80 %, they can still be used for many years for other purposes, for example, as stationary energy storage systems for photovoltaic systems.

• Collaborations with the TU Braunschweig are dedicated to safety-engineering assessments of lithium-ion cells, modules and entire battery systems to be able to make safety-engineering statements in the event of faults such as overloading, overcharging and depth discharging.

• Participation in projects for fundamental research on lithium- sulfur batteries.

Due to its Opens external link in new windowresearch activities, PTB can offer comprehensive services – from the SI-traceable description of the charge condition, the state of health and the safety conditions of lithium batteries to metrology for explosion protection.

 

Departments and working groups involved:

Opens internal link in current windowDepartment 3.1 General and Inorganic Chemistry: state of health of Li ion battery cells

Opens internal link in current windowDepartment 3.6 Explosion Protection in Sensor Technology and Instrumentation: battery safety and management

Opens internal link in current windowWorking Group 1.44 Caloric Quantities

Opens internal link in current windowWorking Group 7.24 X-ray Spectrometry

Opens internal link in current windowWorking Group 8.42 Data Analysis and Measurement Uncertainty

PTB’s competence: hydrogen technology

In the future, green hydrogen (H2) will be a key player in the energy transition. Produced free of CO2 with solar or wind power, green hydrogen is available as an energy carrier for numerous applications in three sectors, i.e. electricity, heat and mobility, and for its utilization as a chemical material in industry. To use green hydrogen comprehensively, many prerequisites will, however, have to be created. PTB is accompanying this process. It is promoting the technological development of the hydrogen economy in terms of metrology and safety engineering, and it is contributing to the setting up of a reliable infrastructure. To this end, PTB intends to build a demonstrator facility of its own on its premises in Braunschweig. PTB is already participating, together with other research partners from Lower Saxony, in the establishment of an innovation laboratory for hydrogen technology. In this laboratory, ideas are to be developed which are close to practical applications and can be implemented for research and transfer concepts.

The measurement competence for many H2-relevant quantities is either already available at PTB or can be set up in the medium term. Besides density, efficiency, calorific value, heat quantity, viscosity and chemical composition, these quantities are as follows:

Pressure: PTB is one of only three metrology institutes worldwide that can measure high pressures in the range of 800 bar with very small uncertainties. In the near future, PTB will expand its measurement capabilities for gas pressures of up to 1000 bar (which may occur during the production, transport and storage of hydrogen).

Temperature: In the field of temperature measurement, PTB operates and develops a wide range of hydrogen-relevant measurement methods, for example, with regard to the thermal management of hydrogen cryogenic-pressure storage tanks.

 

Explosion protection

Hydrogen is an extremely ignitable gas when mixed with air. For a wide range of applications, maximum safety must be guaranteed at all times – whether these applications are close to the consumer (for example, at petrol filling stations) or in industrial processes. In close cooperation with BAM, PTB’s main objective here is the development of test procedures for explosion-protected equipment, the standardization of these procedures and their implementation in the legally regulated conformity assessment procedures.

 

Synthetic fuels

PTB already engages in the analysis and characterization of synthetic hydrogen-based fuels for both aerospace and commercial vehicles. An optimization of tailor-made synthetic fuels for combustion with as few pollutants as possible will only be successful if, for example, the ignition behavior and the reaction kinetics are known.

 

Departments and working groups involved:

Opens internal link in current windowDepartment 3.3 Physical Chemistry: Analytical and preparative metrology for hydrogen and hydrogen-based fuels

Opens internal link in current windowDepartment 3.4 Analytical Chemistry of the Gas Phase: moisture in industrial and energy gases / spectroscopic analysis / reaction kinetics

Opens internal link in current windowDepartment 3.5 Explosion protection in energy technology: H2-MILD combustion technology

Opens internal link in current windowDepartment 3.7 Fundamentals of explosion protection: safety-related consideration of hydrogen

Opens internal link in current windowDepartment 7.4 Temperature: equation of state of hydrogen-methane gas mixtures

Opens internal link in current windowDepartment 7.5 Heat and Vacuum: tightness of high-pressure vessels and pipelines

PTB’s competence: gas measurement technology

In the future, the natural gas grid will serve as a large storage facility for energy from renewable sources. Biogas can be fed into it just as well as hydrogen produced with surplus electricity or methane synthesized from it. If required, it is then converted back into electricity. But gases differ, for example, in their calorific value.

In the interest of fair billing for consumers, it must therefore be possible to determine the chemical and physical properties of the transported gas at any point in the grid as well as the behavior of the gas meters as a reaction to these properties. PTB has the competence to validate such measurement and assessment procedures and to check whether they comply with the requirements of the German Measures and Verification Act. The same applies to gas meters at hydrogen dispensers. In industry, hydrogen is also increasingly used as a gas to control production processes. If it is generated using solar and wind power, green hydrogen can contribute significantly to avoiding CO2 emissions (for example, in steel production).

PTB and the company of Salzgitter Flachstahl GmbH have therefore agreed on a collaboration to develop a suitable hydrogen quantity measurement technology for industry. The accurate measurement of hydrogen is a prerequisite for the efficient control of production processes.

 

Departments involved:

Opens internal link in current windowDepartment 1.4 Gas Flow

Opens internal link in current windowDepartment 3.3 Physical Chemistry

Opens internal link in current windowDepartment 3.4 Analytical Chemistry of the Gas Phase