What exactly is lightweighting?

Find out more about Otto Lilienthal's connection the the energy transition and the lightweight technology that makes it easy to combine economic, resource and energy efficiency. Come this way to find out more!

Illustration:a closer look on lightweighting© BMWi

This is what it’s all about: lightweighting technologies combine great economic potential with resource efficiency. This is important for meeting our national sustainability and climate targets.

Berlin and its surrounding areas are not exactly known for their mountains – a matter of great disappointment to aviation pioneer Otto Lilienthal. After piling up an artificial 'fly hill' of around 15 meters of height close to Berlin for his flight attempts, Lilienthal after many years of trial and error succeeded in performing a controlled gliding flight of around 25 meters. He was the first person to make repeated, successful gliding flights with an aerial vehicle. In 1894, his 'normal soaring apparatus', which only weighed 20 kilograms, went into serial production. More than 120 years later, a solar-powered aircraft, not least thanks to its extremely lightweight construction, for the first time succeeded in circumnavigating the globe using no fossil fuel at all.

The energy transition made easy: achieving economic and resource efficiency in one go

The maths behind this success story is simple: the lower an aircraft's weight, the less energy is required for example to defy gravity. As lightweighting technologies combine great economic potential with resource efficiency, they are today regarded as a key element for transforming the mobility sector in a sustainable manner and for driving forward the expansion of renewable energy. Many other sectors can benefit from this as well. The Federal Ministry for Economic Affairs and Energy's Lightweighting Strategy (in German only), which was published at the beginning of 2021, aims to improve the environment for lightweighting in Germany so as to ensure that the opportunities of this important horizontal technology can be even better harnessed. The strategy also helps Germany edge closer to achieving its national climate and sustainability targets (in German only). The goal is for Germany to become a lead market and leading provider of lightweighting technology. But what exactly is lightweighting? Which sectors use it? Which materials are suitable for lightweight construction and what support mechanisms are available for promoting the technology's roll-out? The basic idea is this: lightweighting means using less material, and less material means lower costs and better properties. As lightweighting components are lower-weight, their use also results in lower energy consumption and less carbon emissions.

Sounds easy enough, but how can this be achieved in practice?

Weight can be reduced for example by using new types of materials or innovative manufacturing and design procedures. By taking account of the principles of lightweighting already during the design and development stages, engineers can integrate features that help reduce the number of assembly steps and improve functionality. Lightweighting products also come with a longer lifespan and can be recycled in a climate-friendly way, which helps reduce the use of resources and cuts carbon emissions.

Need an example? If the weight of a car is reduced by 100 kilograms, its fuel consumption will fall by 0.3 to 0.5 litres per 100 kilometres. And for an electric vehicle, every kilogram less means more range. In an Airbus A 320, 100 kilograms less weight means almost 10,000 litres less kerosene per aircraft and year. This is the reason why lightweighting is used in many areas already today and is a source of innovation in many sectors. A particularly large number of lightweighting products has been developed in aerospace and the automotive and transport industries. And it is also taking on an ever more important role in the construction sector, leisure and sports, the maritime industry, and medical engineering.

Lightweighting materials include plastics and fibre-reinforced plastics using for example carbon or glass, metals and alloys such as aluminium, magnesium and steel, materials from minerals such as ceramics and concrete, and also natural materials such as wood and cellulose. The wide range of materials and use cases of lightweighting makes it a horizontal technology – a technology that can combine innovations from different sectors and use these as a basis for new developments.

Technological solutions for the energy transition

This is a good opportunity for German companies to become leading providers of lightweighting technology at a global scale. The industrial use of new digital tools, materials and manufacturing procedures is to particularly benefit small and medium-sized enterprises (SMEs). Through its Lightweighting Strategy and the dedicated Technology Transfer Programme for Lightweighting (in German only),the Federal Ministry for Economic Affairs and Energy is seeking to speed up the technology transfer and strengthen lightweighting capabilities in the industrial sector. Germany has adopted eight packages of measures for this, for which it has received input from around 350 experts from the business sector and academia. The measures are to help improve the environment for start-ups and SMEs, promote initial and further training and improve networking. In order to promote sustainable lightweighting technologies, the strategy also focuses on the possibility to reuse and recycle products and places greater emphasis on quality assurance methods, early-stage materials assessment and standardised accounting procedures. This also includes the establishment of a digital infrastructure that allows for the resource-efficient development of lightweighting solutions.

The Technology Transfer Programme for Lightweighting is an important instrument of the Lightweighting Strategy. It has an annual volume of around €70 million and fosters knowledge and technology transfer in the lightweighting sector across all industries and materials. Its priorities include technology development, the reduction of carbon emissions and resource efficiency.