Expertise in mechanical engineering is also in demand when innovative development of agricultural machines, and intelligent measurement and control technology, are required for precision agriculture (see section “Agriculture and forestry”). Also essential here are new developments in the area of bio-based lubricants, and for applications of materials from regenerative raw materials for innovative composites – which, in view of growing demand for sustainable production and other industrial processes, are also increasingly pushing into the market. Here as well, engineers must adapt processes and production, and must assure that manufacturing is fit for series production. In addition, food processing depends on new developments from mechanical engineering. This applies above all to automation processes and to robot-aided procedures and production plants. In bioeconomy, mechanical engineering is therefore among those sectors that utilize many cross-linked networks in numerous and various economic sectors, and that must satisfy numerous and different requirements with respect to applied technical equipment.

Great experience has been gained with application of natural resources in the construction of fermenters as they are used in industrial biotechnology. In these steel vessels – also called bioreactors – biological production helpers such as microbes and cells produce large quantities of highly diverse products such as bio-based chemicals, pharmaceuticals, food additives and cosmetic ingredients. New insights in bioengineering deliver the basis here for designing especially efficient production plants – characterized, for example by low energy demand and high degrees of efficiency. Other important factors are special requirements that result from new production cultures (microorganisms) and new producers such as algae. The latter, for instance, can supply the required content substances only if they receive sufficient light. With funding by the BMEL, such photobioreactors are currently being optimized for utilization in industry.

Challenge for measurement and control technology

The greatest challenges associated with fermenters currently involve the continuous monitoring of the bio-based production process, as well as the demanding purification process at the end of the process chain. Not least owing to cost constraints, user industries are interested in minimizing resource consumption. The Alliance for Knowledge-Based Process Intelligence, funded by the BMBF, is involved in challenges such as these. The company Sartorius Lab Instruments GmbH & Co. KG in Göttingen coordinates alliance work in developing an innovative sensor and software platform (see section “Pharmaceuticals”).

The Strategy Process Biotechnology 2020+ was founded in 2010 by the BMBF in conjunction with universities, non-university research organizations, and polytechnics. This process focuses on innovative concepts for biotechnological production methods that extend far beyond the fermentation and biocatalysis processes in use today. Numerous research projects have been launched as based on a roadmap showing essential development and research milestones. The BMBF has funded this endeavour with a total of 60 million euros. In addition to five major projects conducted by research organizations, university and polytechnics researchers throughout Germany are at work in 35 alliances on a great diversity of ideas for future bio-based production. They include bio-based fuel cells, light-controlled biocatalysts and artificial photosynthesis – as well as microsystem engineering approaches intended to exploit metal nanoparticles for production of innovative manufacturing materials. The guiding principle of all projects is close collaboration between biologists and engineers.

Expertise from bio- and engineering sciences is also in demand in the bio-energy sector, especially when involving the enhancement of efficiency in the engineering of biogas facilities. A primary key to profitable operation is particularly the extraction of a maximum of energy from a minimum of biomass (see section “Energy”). From the view of experts, there is still particularly great potential for improvements, especially in production and process engineering – above all in the interlinking of individual process steps. The further development of measurement and control technology, moreover, is also of great significance toward optimizing the fermentation process. An additional major technical challenge exists with respect to engines used in linked combined heat and power plants (CHP), where these facilities must operate also in interval mode and not in uninterrupted mode only. For these engines, change from idle to full-load operation is indeed technically challenging. Furthermore, owing to stagnation in demand for new plant facilities, many biogas plant engineers are focussing more on the international market. It is especially in Italy that this demand has sharply risen owing to state incentives. In France, Denmark, and a number of eastern European countries, to be sure, the demand for German biogas plant engineering companies as exporters is great.

In response to growing demand for bio-based plastics, production engineering has adapted to new requirements, which has led to further developments in injection moulding and related processes. This has involved, for example, composites with natural-fibre reinforcement, and wood-plastic composites. In 2012, 350,000 tons of these hybrid components were manufactured. Not least owing to these developments, Germany represents the most important European market for such products. It can also show a growing list of producers active in this market. Also involved here are numerous research institutions at work on new developments in plastics and wood technologies.
A major challenge involved in the production of bio-based and non-bio-based components is always the requirement for three-dimensional moulding of such parts. This is because wood and natural fibres are less dense than classic mineral fillers and reinforcement materials – a fact which must be considered especially for larger construction components and for light structures. Issues such as these are investigated, for example, at the South German Plastics Centre – one of the four Competency Centres funded by the BMEL in the context of the Biopolymer Network, for development of enhanced processes for treatment of bio-based plastics.

Together with researchers at Paderborn University, studies are underway to determine whether so-called sandwich injection moulding can be used to employ wood-plastic composites as core components in this process – which would thereby open a larger application spectrum to bio-based composites. Sandwich techniques enable production of moulded parts consisting of a core and a skin component. A dedicated injection moulding machine requires a separate injection moulding assembly for each of the two components – each of which must in turn lead to a common nozzle. If such a configuration could be employed without technical problems, wood-plastic composites would also emit less odour. This would in turn make hybrid components more attractive for new applications – for example, in the area of furniture manufacture. Researchers see a greater share of the market owing to the fact that a synthetic skin prevents water absorption – which would prevent deformation and expansion in the bio-component. There are also further developments in this field with press moulding and for dosing systems for machines used in the plastics industry for treatment and shaping operations. Already since 2009, the network alliance FENAFA, funded by the BMEL, has worked on various technical challenges involved in the use of plant-based natural fibres in the manufacture of moulded parts. These parts are widely used in the automotive industry (see section “Automotive sector”), and in the consumer goods industry (see section “Consumer goods”).

From the viewpoint of bioeconomy, mechanical engineering is significant not only in plant engineering and process technology. Indeed: the farming sector also benefits from the ingenuity of German engineers. During recent years precision agriculture has greatly gained in significance (see section “Agriculture and forestry”). To allow precision agriculture to exploit its benefits, numerous individual components are necessary that optimally interlink. Mechanical engineering provides innovations here from measurement and control technology and from automated processes that aid in optimizing work procedures in the fields and in the stalls – thereby contributing to sustainability.

A new development trend in agricultural machine engineering is likewise moving in the direction of field robots. They will primarily be used for heavy and monotonous work in which precise actions over long periods of time are necessary – for example, in fertilizing and sowing. Promising approaches of this kind are also evident in fruit and vegetable cultivation, in which robots can irrigate and harvest. Even sensitive fruit such as strawberries can now be picked by a robot. In addition, sensors are capable of differentiating between ripe and unripe fruits – a key advantage over human harvesters, since much fruit is still being lost in strawberry harvesting when just the right picking time is overlooked. Experts expect, however, that some time will pass before such harvesting helpers are active in German fields on a large scale. Many farmers are still unwilling to make such major investments. Demand is greater at the moment for automated processes in animal husbandry – for example, for milking and feeding animals. Such solutions help above all on large farms to more efficiently monitor applied resources – which contributes to greater sustainability in agriculture (see section “Agriculture and forestry”).

The greenhouse of the future

Mechanical engineers work not only on the open field and in stalls: in greenhouses they are also working toward sustainable agricultural production – for example, in construction of greenhouses. The research centre Forschungszentrum Jülich, for example, is working on new glass types with diffuse light transmission. This means that such glass directs every incident beam of light in a different direction. The benefit here is that all leaves of a plant receive more uniform light than with conventional light. Especially with climbing or tall plants such as tomatoes and cucumbers, the leaves on lower levels lie partially in the shade of those above. With diffuse incidence of light in such cases, yield increases of up to 6 % are possible with the same energy input. By using low-iron solar glass with two-sided anti-reflex coating, advanced greenhouses achieve particularly great light transmission. Almost all the light usable by these plants for photosynthesis actually reaches the leaves, with the result that these light conditions in greenhouses are very similar to those on an open field. From the beginning of a plant under glass, this indurates the plants that will later be transplanted to the open, which prevents losses by ultraviolet burning. Enhanced light transmission not only increases yield but – for a number of plants – greater UV transpar-ency also increases the production of flavour.

Food processing is also dependent on the expertise of engineers to assure resource-efficient and sustainable production processes. Intelligent automation processes, for example, are in demand – for which robotics offers an approach. At the German Institute of Food Technologies (DIL), for instance, intensive research is taking place to develop hygienic gripping techniques that can be flexibly employed. Process analytics is likewise of great significance in this field. It senses and determines the quality of manufactured products and of delivered goods, and provides the systematics for process tracking and control, data analysis and simulation of process procedures. Process analytics ranges from the assay of constituents, to recording of physical and functional characteristics, to tracking and tracing of food products, and finally to product evaluation by the consumer.