New materials enable high speed frequencies: Fraunhofer ISE develops resonant DC/DC converters with 2.5 MHz as demonstrator for aeronautical applications. ©Fraunhofer ISE

The efficiency of power electronic systems is not solely dependent on electrical efficiency but also on weight, for example, in mobile systems. When the weight of relevant components and devices in airplanes, for instance, is reduced, fuel savings can be achieved and correspondingly greenhouse gas emissions decreased. New materials and components based on gallium nitride (GaN) can help to reduce weight and increase the efficiency. With these new materials, power electronic switches can be operated at higher switching frequency, resulting in higher power density and lower material costs.

Nach Stationen in Zürich, Kanada und Schottland erforscht der ERC Starting Grant-Träger Stefan Freunberger an der TU Graz neue Energiespeichersysteme.  © Lunghammer - TU Graz

Forscher der TU Graz zeigt in Nature Materials, dass sich die hohe Energiedichte von Batterien dank flüssigem Ladungsspeicher mit der hohen Leistung von Superkondensatoren in ein System vereinen lässt. Batterien und Superkondensatoren: Die beiden elektrochemischen Energiespeicher sind wie Tag und Nacht. Beide speichern Energie, und beide geben sie gezielt wieder frei – das allerdings mit großen Unterschieden: Batterien speichern sehr große Energiemengen, die sie langsam, aber beständig wieder abgeben. Superkondensatoren können nur geringe Energiemengen speichern, geben diese Energie aber viel leistungsstärker ab und erzielen kurzzeitige Spitzenleistungen.

Liquid energy reservoir: Prof. Josef Hofmann demonstrates how to extract ice-cold biomethane. This compound is a thousand times more energy rich than biogas. Hochschule Landshut

Biogas facilities are important drivers for the energy transition, yet, for many operators, they are no longer profitable. Conversion to biomethane can make such facilities more flexible and energy efficient ─ as well as opening up new business segments to the operators. Researchers at the Landshut University of Applied Sciences and the Weihenstephan-Triesdorf University of Applied Sciences have developed just such a process. Germany is scheduled to be generating 55 to 60 per cent of its electrical power from renewable energy sources by 2025 – currently it is around a third. However, photovoltaic systems only achieve their full capacity during the day in summer, and wind energy plants are usually only viable in exposed areas. The power demand during the dark winter months outstrips the production capacity of renewable sources. To some extent, biogas plants can compensate for these fluctuations and help to secure power continuity.

The BINE Projektinfo brochure entitled "Steel pistons for more efficient diesel engines" © BINE Informationsdienst

Car engines are becoming increasingly compact with a greater specific power. This reduces the weight, moving masses and fuel consumption. In the engine, however, the temperatures and pressures rise for individual components. This causes conventional pistons made of aluminium to reach their limits. The new BINE Projektinfo brochure entitled "Steel pistons for more efficient diesel engines" (14/2016) presents a cooling concept for engine pistons using a liquid metal alloy. Compared with aluminium, steel offers greater strength against thermal and mechanical loads.